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Brassard P, Smirl JD. Dynamic cerebral autoregulation quantification with spontaneous arterial blood pressure oscillations: Is transfer function analysis our best option? Exp Physiol 2024; 109:1015-1017. [PMID: 38615245 PMCID: PMC11215476 DOI: 10.1113/ep091900] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Accepted: 04/03/2024] [Indexed: 04/15/2024]
Affiliation(s)
- Patrice Brassard
- Department of Kinesiology, Faculty of MedicineUniversité LavalQuébecCanada
- Research Center of the Institut universitaire de cardiologie et de pneumologie de QuébecQuébecCanada
| | - Jonathan D. Smirl
- Sport Injury Prevention Research Centre, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Cerebrovascular Concussion Laboratory, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
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Olsen MH, Riberholt C, Capion T, Plovsing RR, Møller K, Berg RMG. Test-retest reliability of transfer function analysis metrics for assessing dynamic cerebral autoregulation to spontaneous blood pressure oscillations. Exp Physiol 2024; 109:1024-1039. [PMID: 38590228 PMCID: PMC11215465 DOI: 10.1113/ep091500] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 03/18/2024] [Indexed: 04/10/2024]
Abstract
Transfer function analysis (TFA) is a widely used method for assessing dynamic cerebral autoregulation in humans. In the present study, we assessed the test-retest reliability of established TFA metrics derived from spontaneous blood pressure oscillations and based on 5 min recordings. The TFA-based gain, phase and coherence in the low-frequency range (0.07-0.20 Hz) from 19 healthy volunteers, 37 patients with subarachnoid haemorrhage and 19 patients with sepsis were included. Reliability assessments included the smallest real difference (SRD) and the coefficient of variance for comparing consecutive 5 min recordings, temporally separated 5 min recordings and consecutive recordings with a minimal length of 10 min. In healthy volunteers, temporally separating the 5 min recordings led to a 0.38 (0.01-0.79) cm s-1 mmHg-1 higher SRD for gain (P = 0.032), and extending the duration of recordings did not affect the reliability. In subarachnoid haemorrhage, temporal separation led to a 0.85 (-0.13 to 1.93) cm s-1 mmHg-1 higher SRD (P = 0.047) and a 20 (-2 to 41)% higher coefficient of variance (P = 0.038) for gain, but neither metric was affected by extending the recording duration. In sepsis, temporal separation increased the SRD for phase by 94 (23-160)° (P = 0.006) but was unaffected by extending the recording. A recording duration of 8 min was required to achieve stable gain and normalized gain measures in healthy individuals, and even longer recordings were required in patients. In conclusion, a recording duration of 5 min appears insufficient for obtaining stable and reliable TFA metrics when based on spontaneous blood pressure oscillations, particularly in critically ill patients with subarachnoid haemorrhage and sepsis.
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Affiliation(s)
- Markus Harboe Olsen
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Christian Riberholt
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Department of Neurorehabilitation/Traumatic Brain Injury Unit, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Tenna Capion
- Department of Neurosurgery, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
| | - Ronni R. Plovsing
- Department of Anaesthesia and Intensive CareCopenhagen University Hospital – HvidovreCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Kirsten Møller
- Department of Neuroanaesthesiology, The Neuroscience CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Department of Clinical Medicine, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
| | - Ronan M. G. Berg
- Department of Clinical Physiology and Nuclear Medicine, The Diagnostic CentreCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Centre for Physical Activity ResearchCopenhagen University Hospital – RigshospitaletCopenhagenDenmark
- Department of Biomedical Sciences, Faculty of Health and Medical SciencesUniversity of CopenhagenCopenhagenDenmark
- Neurovascular Research Laboratory, Faculty of Life Sciences and EducationUniversity of South WalesPontypriddUK
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Burma JS, Smirl JD. Letter to the editor: Deriving transfer function analysis metrics from driven methods. J Cereb Blood Flow Metab 2024; 44:1053-1056. [PMID: 38466898 DOI: 10.1177/0271678x231224504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 03/13/2024]
Abstract
Driven and spontaneous methods have been used to quantify the cerebral pressure-flow relationship via transfer function analysis (TFA). Commonly, TFA derived estimates are assessed using band averages within the very-low (0.02-0.07 Hz) and low (0.07-0.20 Hz) frequency during spontaneous oscillations but are quantified at frequencies of interest where blood pressure oscillations are driven (e.g., 0.05 and/or 0.10 Hz). Driven estimates more closely resemble the autoregulatory challenges individuals experience on a daily basis, while also eliciting higher levels of reliability. While driven estimates with point-estimates are not feasible for all clinical populations, these approaches increase the ability to understand pathophysiological changes.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
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Kostoglou K, Bello-Robles F, Brassard P, Chacon M, Claassen JA, Czosnyka M, Elting JW, Hu K, Labrecque L, Liu J, Marmarelis VZ, Payne SJ, Shin DC, Simpson D, Smirl J, Panerai RB, Mitsis GD. Time-domain methods for quantifying dynamic cerebral blood flow autoregulation: Review and recommendations. A white paper from the Cerebrovascular Research Network (CARNet). J Cereb Blood Flow Metab 2024:271678X241249276. [PMID: 38688529 DOI: 10.1177/0271678x241249276] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Abstract
Cerebral Autoregulation (CA) is an important physiological mechanism stabilizing cerebral blood flow (CBF) in response to changes in cerebral perfusion pressure (CPP). By maintaining an adequate, relatively constant supply of blood flow, CA plays a critical role in brain function. Quantifying CA under different physiological and pathological states is crucial for understanding its implications. This knowledge may serve as a foundation for informed clinical decision-making, particularly in cases where CA may become impaired. The quantification of CA functionality typically involves constructing models that capture the relationship between CPP (or arterial blood pressure) and experimental measures of CBF. Besides describing normal CA function, these models provide a means to detect possible deviations from the latter. In this context, a recent white paper from the Cerebrovascular Research Network focused on Transfer Function Analysis (TFA), which obtains frequency domain estimates of dynamic CA. In the present paper, we consider the use of time-domain techniques as an alternative approach. Due to their increased flexibility, time-domain methods enable the mitigation of measurement/physiological noise and the incorporation of nonlinearities and time variations in CA dynamics. Here, we provide practical recommendations and guidelines to support researchers and clinicians in effectively utilizing these techniques to study CA.
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Affiliation(s)
- Kyriaki Kostoglou
- Department of Electrical and Computer Engineering, McGill University, Montreal, QC, Canada
- Institute of Neural Engineering, Graz University of Technology, Graz, Austria
| | - Felipe Bello-Robles
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec, QC, Canada
| | - Max Chacon
- Departamento de Ingeniería Informática, Universidad de Santiago de Chile, Santiago, Chile
| | - Jurgen Ahr Claassen
- Department of Geriatrics, Radboud University Medical Center, Research Institute for Medical Innovation and Donders Institute, Nijmegen, The Netherlands
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM), Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Marek Czosnyka
- Department of Clinical Neurosciences, Neurosurgery Department, University of Cambridge, Cambridge, UK
| | - Jan-Willem Elting
- Department of Neurology and Clinical Neurophysiology, University Medical Center Groningen, Groningen, The Netherlands
| | - Kun Hu
- Medical Biodynamics Program, Division of Sleep and Circadian Disorders, Brigham and Women's Hospital, Harvard Medical School, Boston, MA, USA
- Division of Sleep Medicine, Harvard Medical School, Boston, MA, USA
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec, QC, Canada
- Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec, QC, Canada
| | - Jia Liu
- Laboratory for Engineering and Scientific Computing, Institute of Advanced Computing and Digital Engineering, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, Guangdong, China
| | - Vasilis Z Marmarelis
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei, Taiwan
| | - Dae Cheol Shin
- Department Biomedical Engineering, Viterbi School of Engineering, University of Southern California, Los Angeles, CA, USA
| | - David Simpson
- Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
| | - Jonathan Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
| | - Ronney B Panerai
- Cerebral Haemodynamics in Ageing and Stroke Medicine (CHiASM), Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
- NIHR Leicester Biomedical Research Centre, British Heart Foundation, Glenfield Hospital, Leicester, UK
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montreal, QC, Canada
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Burma JS, Roy MA, Kennedy CM, Labrecque L, Brassard P, Smirl JD. A systematic review, meta-analysis, and meta-regression amalgamating the driven approaches used to quantify dynamic cerebral autoregulation. J Cereb Blood Flow Metab 2024:271678X241235878. [PMID: 38635887 DOI: 10.1177/0271678x241235878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/20/2024]
Abstract
Numerous driven techniques have been utilized to assess dynamic cerebral autoregulation (dCA) in healthy and clinical populations. The current review aimed to amalgamate this literature and provide recommendations to create greater standardization for future research. The PubMed database was searched with inclusion criteria consisting of original research articles using driven dCA assessments in humans. Risk of bias were completed using Scottish Intercollegiate Guidelines Network and Methodological Index for Non-Randomized Studies. Meta-analyses were conducted for coherence, phase, and gain metrics at 0.05 and 0.10 Hz using deep-breathing, oscillatory lower body negative pressure (OLBNP), sit-to-stand maneuvers, and squat-stand maneuvers. A total of 113 studies were included, with 40 of these incorporating clinical populations. A total of 4126 participants were identified, with younger adults (18-40 years) being the most studied population. The most common techniques were squat-stands (n = 43), deep-breathing (n = 25), OLBNP (n = 20), and sit-to-stands (n = 16). Pooled coherence point estimates were: OLBNP 0.70 (95%CI:0.59-0.82), sit-to-stands 0.87 (95%CI:0.79-0.95), and squat-stands 0.98 (95%CI:0.98-0.99) at 0.05 Hz; and deep-breathing 0.90 (95%CI:0.81-0.99); OLBNP 0.67 (95%CI:0.44-0.90); and squat-stands 0.99 (95%CI:0.99-0.99) at 0.10 Hz. This review summarizes clinical findings, discusses the pros/cons of the 11 unique driven techniques included, and provides recommendations for future investigations into the unique physiological intricacies of dCA.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Canada
| | - Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Courtney M Kennedy
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Canada
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Canada
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Labrecque L, Roy MA, Soleimani Dehnavi S, Taghizadeh M, Smirl JD, Brassard P. Directional sensitivity of the cerebral pressure-flow relationship during forced oscillations induced by oscillatory lower body negative pressure. J Cereb Blood Flow Metab 2024:271678X241247633. [PMID: 38613236 DOI: 10.1177/0271678x241247633] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 04/14/2024]
Abstract
A directional sensitivity of the cerebral pressure-flow relationship has been described using repeated squat-stands. Oscillatory lower body negative pressure (OLBNP) is a reproducible method to characterize dynamic cerebral autoregulation (dCA). It could represent a safer method to examine the directional sensitivity of the cerebral pressure-flow relationship within clinical populations and/or during pharmaceutical administration. Therefore, examining the cerebral pressure-flow directional sensitivity during an OLBNP-induced cyclic physiological stress is crucial. We calculated changes in middle cerebral artery mean blood velocity (MCAv) per alterations to mean arterial pressure (MAP) to compute ratios adjusted for time intervals (ΔMCAvT/ΔMAPT) with respect to the minimum-to-maximum MCAv and MAP, for each OLBNP transition (0 to -90 Torr), during 0.05 Hz and 0.10 Hz OLBNP. We then compared averaged ΔMCAvT/ΔMAPT during OLBNP-induced MAP increases (INC) (ΔMCAvT/Δ MAP T INC ) and decreases (DEC) (ΔMCAvT/Δ MAP T DEC ). Nineteen healthy participants [9 females; 30 ± 6 years] were included. There were no differences in ΔMCAvT/ΔMAPT between INC and DEC at 0.05 Hz. ΔMCAvT/Δ MAP T INC (1.06 ± 0.35 vs. 1.33 ± 0.60 cm⋅s-1/mmHg; p = 0.0076) was lower than ΔMCAvT/Δ MAP T DEC at 0.10 Hz. These results support OLBNP as a model to evaluate the directional sensitivity of the cerebral pressure-flow relationship.
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Affiliation(s)
- Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Shahrzad Soleimani Dehnavi
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Mahmoudreza Taghizadeh
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Jonathan D Smirl
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
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Whitaker AA, Aaron SE, Chertoff M, Brassard P, Buchanan J, Nguyen K, Vidoni ED, Waghmare S, Eickmeyer SM, Montgomery RN, Billinger SA. Lower dynamic cerebral autoregulation following acute bout of low-volume high-intensity interval exercise in chronic stroke compared to healthy adults. J Appl Physiol (1985) 2024; 136:707-720. [PMID: 38357728 DOI: 10.1152/japplphysiol.00635.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 01/23/2024] [Accepted: 02/04/2024] [Indexed: 02/16/2024] Open
Abstract
Fluctuating arterial blood pressure during high-intensity interval exercise (HIIE) may challenge dynamic cerebral autoregulation (dCA), specifically after stroke after an injury to the cerebrovasculature. We hypothesized that dCA would be attenuated at rest and during a sit-to-stand transition immediately after and 30 min after HIIE in individuals poststroke compared with age- and sex-matched control subjects (CON). HIIE switched every minute between 70% and 10% estimated maximal watts for 10 min. Mean arterial pressure (MAP) and middle cerebral artery blood velocity (MCAv) were recorded. dCA was quantified during spontaneous fluctuations in MAP and MCAv via transfer function analysis. For sit-to-stand, time delay before an increase in cerebrovascular conductance index (CVCi = MCAv/MAP), rate of regulation, and % change in MCAv and MAP were measured. Twenty-two individuals poststroke (age 60 ± 12 yr, 31 ± 16 mo) and twenty-four CON (age 60 ± 13 yr) completed the study. Very low frequency (VLF) gain (P = 0.02, η2 = 0.18) and normalized gain (P = 0.01, η2 = 0.43) had a group × time interaction, with CON improving after HIIE whereas individuals poststroke did not. Individuals poststroke had lower VLF phase (P = 0.03, η2 = 0.22) after HIIE compared with CON. We found no differences in the sit-to-stand measurement of dCA. Our study showed lower dCA during spontaneous fluctuations in MCAv and MAP following HIIE in individuals poststroke compared with CON, whereas the sit-to-stand response was maintained.NEW & NOTEWORTHY This study provides novel insights into poststroke dynamic cerebral autoregulation (dCA) following an acute bout of high-intensity interval exercise (HIIE). In people after stroke, dCA appears attenuated during spontaneous fluctuations in mean arterial pressure (MAP) and middle cerebral artery blood velocity (MCAv) following HIIE. However, the dCA response during a single sit-to-stand transition after HIIE showed no significant difference from controls. These findings suggest that HIIE may temporarily challenge dCA after exercise in individuals with stroke.
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Affiliation(s)
- Alicen A Whitaker
- Department of Physical Therapy, Rehabilitation Science, and Athletic Training, University of Kansas Medical Center, Kansas City, Kansas, United States
- Department of Physical Medicine and Rehabilitation, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
- Cardiovascular Center, Medical College of Wisconsin, Milwaukee, Wisconsin, United States
| | - Stacey E Aaron
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Mark Chertoff
- Department of Hearing and Speech, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Quebec, Canada
- Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec-Université Laval, Quebec City, Quebec, Canada
| | - Jake Buchanan
- Department of Physical Therapy, Rehabilitation Science, and Athletic Training, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Katherine Nguyen
- Department of Physical Therapy, Rehabilitation Science, and Athletic Training, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Eric D Vidoni
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, United States
- University of Kansas Alzheimer's Disease Research Center, Fairway, Kansas, United States
| | - Saniya Waghmare
- Department of Physical Therapy, Rehabilitation Science, and Athletic Training, University of Kansas Medical Center, Kansas City, Kansas, United States
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Sarah M Eickmeyer
- Department of Physical Medicine and Rehabilitation, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Robert N Montgomery
- Department of Biostatistics & Data Science, University of Kansas Medical Center, Kansas City, Kansas, United States
| | - Sandra A Billinger
- Department of Neurology, University of Kansas Medical Center, Kansas City, Kansas, United States
- University of Kansas Alzheimer's Disease Research Center, Fairway, Kansas, United States
- Department of Physical Medicine and Rehabilitation, University of Kansas Medical Center, Kansas City, Kansas, United States
- Department of Cell Biology and Physiology, University of Kansas Medical Center, Kansas City, Kansas, United States
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Ellingson CA, Singh J, Ellingson CJ, Shafiq MA, Sirant LW, Dorsch KD, Gruszecki M, Kratzig GP, Neary JP. Sport-related concussion alters cerebral hemodynamic activity during controlled respiration. J Neurophysiol 2024; 131:556-561. [PMID: 38324895 DOI: 10.1152/jn.00477.2023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2023] [Revised: 01/25/2024] [Accepted: 02/07/2024] [Indexed: 02/09/2024] Open
Abstract
Sport-related concussion (SRC) is known to disrupt neurohemodynamic activity, cardiac function, and blood pressure (BP) autoregulation. This study aims to observe changes in cerebrovascular and cardiovascular responses during controlled respiration after sustaining an SRC. University varsity athletes (n = 81) completed a preseason physiological assessment and were followed up within 5 days of sustaining an SRC. During preseason and follow-up assessments, participants' continuous beat-to-beat BP was collected by finger photoplethysmography, and right prefrontal cortex oxygenation was collected using near-infrared spectroscopy (NIRS). Participants completed 5 min of seated rest and 5 min of a 6-breaths per minute controlled breathing protocol (5 s inhale and 5 s exhale; 0.10 Hz). Wavelet transformation was applied to the NIRS and BP signals, separating them into respiratory (0.10-0.6 Hz) and cardiac (0.6-2 Hz) frequency intervals. Of the 81 participants, 74 had a usable BP signal, 43 had usable NIRS signals, and 28 had both usable BP and NIRS signals. Wavelet amplitudes were calculated and coherence between NIRS and BP on the 28 participants were assessed. There was a significant (P < 0.05) decrease in oxygenated hemoglobin amplitude from 0.062 to 0.054 Hz and hemoglobin difference amplitude from 0.059 to 0.051 Hz, both at the respiratory (0.10-0.6 Hz) frequency interval, from preseason to acute SRC, respectively. Therefore, during controlled respiration, there was a reduction in intensity at the respiratory band, suggesting a protective, reduced respiratory contribution to cerebral hemodynamic activity following acute SRC.NEW & NOTEWORTHY This study investigated cerebral hemodynamic activity following sport-related concussion. Prefrontal cortex oxygenation was assessed by near-infrared spectroscopy (NIRS) during a controlled breathing protocol. Wavelet transformation of the NIRS signals showed significant decreases in HbO2 and HbD amplitude at the respiratory frequency interval (0.10-0.6 HZ) from preseason baseline to acute concussion. These results suggest a decreased respiratory contribution to cerebral hemodynamic activity following acute concussion.
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Affiliation(s)
- Cody A Ellingson
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, Saskatchewan, Canada
| | - Jyotpal Singh
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, Saskatchewan, Canada
| | - Chase J Ellingson
- College of Medicine, University of Saskatchewan, Regina, Saskatchewan, Canada
| | - M Abdullah Shafiq
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, Saskatchewan, Canada
| | - Luke W Sirant
- College of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada
| | - Kim D Dorsch
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, Saskatchewan, Canada
| | - Marcin Gruszecki
- Department of Radiology Informatics and Statistics, Faculty of Health Sciences, Medical University of Gdansk, Gdansk, Poland
- Department of Biomedical Engineering, Faculty of Electronics, Telecommunications and Informatics, Gdansk University of Technology, Gdansk, Poland
| | - Gregory P Kratzig
- Department of Psychology, University of Regina, Regina, Saskatchewan, Canada
| | - J Patrick Neary
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, Saskatchewan, Canada
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Wallis WEG, Al-Alem Q, Lorimer H, Smail OJ, Williams GKR, Bond B. The acute influence of amateur boxing on dynamic cerebral autoregulation and cerebrovascular reactivity to carbon dioxide. Eur J Appl Physiol 2024; 124:993-1003. [PMID: 37768343 PMCID: PMC10879355 DOI: 10.1007/s00421-023-05324-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2023] [Accepted: 09/14/2023] [Indexed: 09/29/2023]
Abstract
PURPOSE The purpose of this study was to investigate the acute effect of head impacts, sustained over the course of three rounds of amateur boxing, on indices of cerebrovascular function. METHODS Eighteen university amateur boxers (six female) completed three experimental trials in a randomised order; (1) three rounds of boxing (BOX), (2) an equivalent bout of pad boxing (where no blows to the head were sustained; PAD), and (3) a time-matched seated control trial (CON). Indices of cerebrovascular function were determined immediately before and 45 min after each trial. Specifically, dynamic cerebral autoregulation (dCA) was determined by considering the relationship between changes in cerebral blood velocity and mean arterial pressure during 5 min of squat-stand manoeuvres at 0.05 and 0.10 Hz. Cerebrovascular reactivity was determined using serial breath holding and hyperventilation attempts. RESULTS Participants received an average of 40 ± 16 punches to the head during the BOX trial. Diastolic, mean and systolic dCA phase during squat stand manoeuvres at 0.05 Hz was lower after BOX compared to pre BOX (P ≤ 0.02, effect size (d) ≥ 0.74). No other alterations in dCA outcomes were observed at 0.05 or 0.10 Hz. The number of head impacts received during the BOX trial was associated with the change in systolic phase (r = 0.50, P = 0.03). No differences in cerebrovascular reactivity to breath holding or hyperventilation were observed. CONCLUSIONS A typical bout of amateur boxing (i.e., three rounds) can subtly alter cerebral pressure-flow dynamics, and the magnitude of this change may be related to head impact exposure.
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Affiliation(s)
- W E G Wallis
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK
| | - Q Al-Alem
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK
| | - H Lorimer
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK
| | - O J Smail
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK
| | - G K R Williams
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK
| | - B Bond
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) research group, Sport and Health Sciences, Baring Court, St Luke's Campus, University of Exeter, Exeter, EX1 2LU, UK.
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Burma JS, Griffiths JK, Smirl JD. Validity and reliability of deriving the autoregulatory plateau through projection pursuit regression from driven methods. Physiol Rep 2024; 12:e15919. [PMID: 38262711 PMCID: PMC10805621 DOI: 10.14814/phy2.15919] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2023] [Revised: 12/19/2023] [Accepted: 01/09/2024] [Indexed: 01/25/2024] Open
Abstract
To compare the construct validity and between-day reliability of projection pursuit regression (PPR) from oscillatory lower body negative pressure (OLBNP) and squat-stand maneuvers (SSMs). Nineteen participants completed 5 min of OLBNP and SSMs at driven frequencies of 0.05 and 0.10 Hz across two visits. Autoregulatory plateaus were derived at both point-estimates and across the cardiac cycle. Between-day reliability was assessed with intraclass correlation coefficients (ICCs), Bland-Altman plots with 95% limits of agreement (LOA), coefficient of variation (CoV), and smallest real differences. Construct validity between OLBNP-SSMs were quantified with Bland-Altman plots and Cohen's d. The expected autoregulatory curve with positive rising and negative falling slopes were present in only ~23% of the data. The between-day reliability for the ICCs were poor-to-good with the CoV estimates ranging from ~50% to 70%. The 95% LOA were very wide with an average spread of ~450% for OLBNP and ~350% for SSMs. Plateaus were larger from SSMs compared to OLBNPs (moderate-to-large effect sizes). The cerebral pressure-flow relationship is a complex regulatory process, and the "black-box" nature of this system can make it challenging to quantify. The current data reveals PPR analysis does not always elicit a clear-cut central plateau with distinctive rising/falling slopes.
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Affiliation(s)
- Joel S. Burma
- Cerebrovascular Concussion Lab, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Sport Injury Prevention Research Centre, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance Laboratory, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryCalgaryAlbertaCanada
| | - James K. Griffiths
- Cerebrovascular Concussion Lab, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Faculty of Biomedical EngineeringUniversity of CalgaryCalgaryAlbertaCanada
| | - Jonathan D. Smirl
- Cerebrovascular Concussion Lab, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Sport Injury Prevention Research Centre, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance Laboratory, Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryCalgaryAlbertaCanada
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11
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Miutz LN, Burma JS, Brassard P, Phillips AA, Emery CA, Smirl JD. Comparison of the Buffalo Concussion Treadmill Test With a Physiologically Informed Cycle Test: Calgary Concussion Cycle Test. Sports Health 2023:19417381231217744. [PMID: 38149331 DOI: 10.1177/19417381231217744] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2023] Open
Abstract
BACKGROUND Sport-related concussions are a complex injury requiring multifaceted assessment, including physical exertion. Currently, concussion testing relies primarily on a treadmill-based protocol for assessing exertion-related symptoms in persons after concussion. This study compared a modified cycle protocol (Calgary Concussion Cycle Test [CCCT]) with the clinically adopted standard, the Buffalo Concussion Treadmill Test (BCTT), across multiple physiological parameters. HYPOTHESIS Treadmill and cycle matched workload protocols would produce similar results for cerebral blood velocity, mean arterial pressure (MAP), and end-tidal carbon dioxide partial pressure (PETCO2), but heart rate (HR) and oxygen consumption (VO2) would be higher on the treadmill than the cycle modality. STUDY DESIGN Crossover study design. LEVEL OF EVIDENCE Level 3. METHODS A total of 17 healthy adults (8 men, 9 women; age, 26 ± 3 years; body mass index, 23.8 ± 2.7 kg/m2) completed the BCTT and CCCT protocols, 7 days apart in a randomized order. During both exertional protocols, the physiological parameters measured were middle cerebral artery mean blood velocity (MCAv), MAP, PETCO2, VO2, and HR. Analysis of variance with effect size computations, coefficient of variation, and Bland-Altman plots with 95% limits of agreement were used to compare exercise tests. RESULTS The BCTT and CCCT produced comparable results for both male and female participants with no significant differences for average MCAv, MAP, and PETCO2 (all P > 0.05; all generalized eta squared [η2G] < 0.02 [negligible]; P value range, 0.29-0.99) between stages. When accounting for exercise stage and modality, VO2 (P < 0.01) and HR (P < 0.01) were higher on the treadmill compared with the cycle. Aside from the final few stages, all physiology measures displayed good-to-excellent agreeability/variability. CONCLUSION The CCCT was physiologically similar to the BCTT in terms of MCAv, PETCO2, and MAP; however, HR and VO2 differed between modalities. CLINICAL RELEVANCE Providing a cycle-based modality to exertional testing after injury mayincrease accessibility to determine symptom thresholds in the future.
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Affiliation(s)
- Lauren N Miutz
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Department of Health and Sport Science, University of Dayton, Dayton, Ohio
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, University Laval, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Aaron A Phillips
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Departments of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, Biomedical Engineering, and Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Carolyn A Emery
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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12
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Brassard P, Roy MA, Burma JS, Labrecque L, Smirl JD. Quantification of dynamic cerebral autoregulation: welcome to the jungle! Clin Auton Res 2023; 33:791-810. [PMID: 37758907 DOI: 10.1007/s10286-023-00986-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2023] [Accepted: 09/11/2023] [Indexed: 09/29/2023]
Abstract
PURPOSE Patients with dysautonomia often experience symptoms such as dizziness, syncope, blurred vision and brain fog. Dynamic cerebral autoregulation, or the ability of the cerebrovasculature to react to transient changes in arterial blood pressure, could be associated with these symptoms. METHODS In this narrative review, we go beyond the classical view of cerebral autoregulation to discuss dynamic cerebral autoregulation, focusing on recent advances pitfalls and future directions. RESULTS Following some historical background, this narrative review provides a brief overview of the concept of cerebral autoregulation, with a focus on the quantification of dynamic cerebral autoregulation. We then discuss the main protocols and analytical approaches to assess dynamic cerebral autoregulation, including recent advances and important issues which need to be tackled. CONCLUSION The researcher or clinician new to this field needs an adequate comprehension of the toolbox they have to adequately assess, and interpret, the complex relationship between arterial blood pressure and cerebral blood flow in healthy individuals and clinical populations, including patients with autonomic disorders.
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Affiliation(s)
- Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada.
| | - Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada
- Research center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, AB, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, AB, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, AB, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
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13
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Wang Y, Payne SJ. Static autoregulation in humans. J Cereb Blood Flow Metab 2023:271678X231210430. [PMID: 37933742 DOI: 10.1177/0271678x231210430] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2023]
Abstract
The process by which cerebral blood flow (CBF) remains approximately constant in response to short-term variations in arterial blood pressure (ABP) is known as cerebral autoregulation. This classic view, that it remains constant over a wide range of ABP, has however been challenged by a growing number of studies. To provide an updated understanding of the static cerebral pressure-flow relationship and to characterise the autoregulation curve more rigorously, we conducted a comprehensive literature research. Results were based on 143 studies in healthy individuals aged 18 to 65 years. The mean sensitivities of CBF to changes in ABP were found to be 1.47 ± 0.71%/% for decreased ABP and 0.37 ± 0.38%/% for increased ABP. The significant difference in CBF directional sensitivity suggests that cerebral autoregulation appears to be more effective in buffering increases in ABP than decreases in ABP. Regression analysis of absolute CBF and ABP identified an autoregulatory plateau of approximately 20 mmHg (ABP between 80 and 100 mmHg), which is much smaller than the widely accepted classical view. Age and sex were found to have no effect on autoregulation strength. This data-driven approach provides a quantitative method of analysing static autoregulation that can be easily updated as more experimental data become available.
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Affiliation(s)
- Yufan Wang
- Institute of Biomedical Engineering, Department of Engineering Science, University of Oxford, Oxford, UK
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei
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14
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Burma JS, Seok J, Johnston NE, Smirl JD. Cerebral blood velocity during concurrent supine cycling, lower body negative pressure, and head-up tilt challenges: implications for concussion rehabilitation. Physiol Meas 2023; 44:084002. [PMID: 37531960 DOI: 10.1088/1361-6579/acecd4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Accepted: 08/02/2023] [Indexed: 08/04/2023]
Abstract
Introduction. The effect of concurrent head-up tilt and lower body negative pressure (LBNP) have been examined on middle cerebral artery velocity (MCAv) at rest; however, it is unknown the superimposed effect these factors have on blunting the elevation in cerebral blood velocity associated with moderate-intensity exercise.Methods. 23 healthy adults (11 females / 12 males, 20-33 years) completed three visits. The first consisted of a maximal ramp supine cycling test to identify the wattage associated with individualized maximal MCAv. Subsequent visits included randomized no LBNP (control) or LBNP at -40 Torr (experimental) with successively increasing head-up tilt stages of 0, 15, 30, and 45 degrees during the pre-described individualized wattage. Transcranial Doppler ultrasound was utilized to quantify MCAv. Two-factorial repeated measures analysis of variance with effect sizes were used to determine differences between days and tilt stages.Results. Between-day baseline values for MCAv, heart rate, and blood pressure displayed low variability with <5% variation. With no LBNP, MCAv was above baseline on average for all participants; however, 15 degrees and 30 degrees tilt with concurrent -40 Torr LBNP was sufficient to return MCAv to 100% of baseline values in females and males, respectively. Body-weight did not impact the association between tilt and pressure (R2range: 0.01-0.12).Conclusion. Combined LBNP and tilt were sufficient to reduce the increase in MCAv associated with moderate-intensity exercise. This exercise modality shows utility to enable individuals with a concussion to obtain the positive physiological adaptions associated with exercise while minimizing symptom exacerbation due to the notion of the Monro-Kellie doctrine.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Jina Seok
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
| | - Nathan E Johnston
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
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15
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Miutz LN, Burma JS, Van Roessel RK, Johnson NE, Phillips AA, Emery CA, Brassard P, Smirl JD. The effect of supine cycling and progressive lower body negative pressure on cerebral blood velocity responses. J Appl Physiol (1985) 2023; 135:316-325. [PMID: 37348016 DOI: 10.1152/japplphysiol.00758.2022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2022] [Revised: 06/08/2023] [Accepted: 06/08/2023] [Indexed: 06/24/2023] Open
Abstract
Moderate-intensity aerobic exercise increases cerebral blood velocity (CBv) primarily due to hyperpnea-induced vasodilation; however, the integrative control of cerebral blood flow (CBF) allows other factors to contribute to the vasodilation. Although lower body negative pressure (LBNP) can reduce CBv, the exact LBNP intensity required to blunt the aforementioned exercise-induced CBv response is unknown. This could hold utility for concussion recovery, allowing individuals to exercise at higher intensities without symptom exacerbation. Thirty-two healthy adults (age: 20-33 yr; 19 females/13 males) completed a stepwise maximal exercise test during a first visit to determine each participant's wattage associated with their exercise-induced maximal CBv increase. During the second visit, following supine rest, participants completed moderate-intensity exercise at their determined threshold, while progressive LBNP was applied at 0, -20, -40, -60, -70, -80, and ∼88 Torr. Bilateral middle cerebral artery blood velocities (MCAvs), mean arterial pressure (MAP), heart rate, respiratory rate, and end-tidal carbon dioxide levels were measured continuously. Two-way analysis of variance with effect sizes compared between sexes and stages. Compared with resting supine baseline, averaged MCAv was elevated during 0 and -20 Torr LBNP (q value > 7.73; P < 0.001); however, no differences were noted between baseline and -40 to -70 Torr (q value < |4.24|; P > 0.262). Differences were present between females and males for absolute MCAv measures (q value > 11.2; P < 0.001), but not when normalized to baseline (q value < 0.03; P > 0.951). Supine cycling-elicited increases in MCAv are able to be blunted during the application of LBNP ranging from -40 to -70 Torr. The blunted CBv response demonstrates the potential benefit of allowing individuals to aerobically train (moderate-intensity supine cycling with LBNP) without exacerbating symptoms during the concussion recovery phase.NEW & NOTEWORTHY The current investigation demonstrated that moderate-intensity supine cycling-induced increases in cerebral blood velocities were balanced by the lower body negative pressure-induced decreases in cerebral blood velocity. Although performed in a healthy population, the results may lend themselves to a potential treatment option for individuals recovering from concussion or experience persistent concussion symptoms.
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Affiliation(s)
- Lauren N Miutz
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Department of Health and Sport Science, University of Dayton, Dayton, Ohio, United States
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Rowan K Van Roessel
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Nathan E Johnson
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Aaron A Phillips
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Departments of Physiology and Pharmacology, Clinical Neurosciences, Cardiac Sciences, University of Calgary, Calgary, Alberta, Canada
- Biomedical Engineering, and Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Carolyn A Emery
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, University Laval, Quebec City, Québec, Canada
- Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Quebec City, Québec, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
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Burma JS, Rattana S, Oni IK, Lapointe AP, Dunn JF, Smirl JD. The temporal neurovascular coupling response remains intact during sinusoidal hypotensive and hypertensive challenges. Physiol Meas 2023; 44:074002. [PMID: 37399810 DOI: 10.1088/1361-6579/ace3a2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Accepted: 07/03/2023] [Indexed: 07/05/2023]
Abstract
Introduction. Neurovascular coupling (NVC) describes the coupling of neuronal metabolic demand to blood supply, which has shown to be impaired with chronic hypertension, as well as with prolonged hypotension. However, it is unknown the extent the NVC response remains intact during transient hypo- and hyper-tensive challenges.Methods. Fifteen healthy participants (9 females/6 males) completed a visual NVC task ('Where's Waldo?') over two testing sessions, consisting of cyclical 30 s eyes closed and opened portions. The Waldo task was completed at rest (8 min) and concurrently during squat-stand maneuvers (SSMs; 5 min) at 0.05 Hz (10 s squat/stand) and 0.10 Hz (5 s squat-stand). SSMs induce 30-50 mmHg blood pressure oscillations, resulting in cyclical hypo- and hyper-tensive swings within the cerebrovasculature, allowing for the quantification of the NVC response during transient hypo- and hyper-tension. Outcome NVC metrics included baseline, peak, relative increase in cerebral blood velocity (CBv), and area-under-the-curve (AUC30) within the posterior and middle cerebral arteries indexed via transcranial Doppler ultrasound. Within-subject, between-task comparisons were conducted using analysis of variance with effect size calculations.Results. Differences were noted between rest and SSM conditions in both vessels for peak CBv (allp< 0.045) and the relative increase in CBv (allp <0.049) with small-to-large effect sizes. AUC30 metrics were similar between all tasks (allp> 0.090) with negligible-to-small effect sizes.Conclusions. Despite the SSMs eliciting ∼30-50 mmHg blood pressure oscillations, similar levels of activation occurred within the neurovascular unit across all conditions. This demonstrated the signaling of the NVC response remained intact during cyclical blood pressure challenges.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Selina Rattana
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
| | - Ibukunoluwa K Oni
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Andrew P Lapointe
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jeff F Dunn
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
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17
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Abadjiev DS, Toschi-Dias E, Salinet ASM, Gaykova NN, Lo MT, Nogueira RC, Hu K. Daily rhythm of dynamic cerebral autoregulation in patients after stroke. J Cereb Blood Flow Metab 2023; 43:989-998. [PMID: 36722135 PMCID: PMC10196745 DOI: 10.1177/0271678x231153750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Revised: 12/02/2022] [Accepted: 01/02/2022] [Indexed: 02/02/2023]
Abstract
Dynamic cerebral autoregulation (dCA) in healthy young adults displays a daily variation. Whether the rhythm exists in patients with stroke is unknown. We studied 28 stroke patients (age: 26-83 years, 7 females) within 48 hours after thrombolysis. dCA was assessed 54 times in these patients during supine rest (twice in 26 and once in 2 patients): 9 assessments between 0-9AM, 12 between 9AM-2PM, 20 between 2-7PM, and 13 between 7PM-12AM. To estimate dCA, phase shifts between spontaneous oscillations of cerebral blood flow velocity (CBFV) in the middle cerebral artery and arterial blood pressure (BP) were obtained in four frequency bands: <0.05 Hz, 0.05-0.1 Hz, 0.1-0.2 Hz, and >0.2 Hz. CBFV-BP phase shifts at <0.05 Hz were significantly larger between 2-7PM, suggesting better dCA, than those at other times (p < 0.0001), and the daily rhythm was consistent for stroke and non-stroke sides. No significant rhythms were observed at higher frequencies (all p > 0.2). All results were independent of age, sex, stroke type and severity, and other cardiovascular conditions. dCA after stroke showed a daily rhythm, leading to a better regulation of CBFV at <0.05 Hz during the afternoon. The finding may have implications for daily activity management of stroke patients.
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Affiliation(s)
- Daniel S Abadjiev
- Medical Biodynamics Program,
Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Harvard
Medical School, Boston, MA, USA
| | - Edgar Toschi-Dias
- Neurology Department, School of
Medicine, Hospital das Clinicas, University of São Paulo, São Paulo ,
Brazil
| | - Angela SM Salinet
- Neurology Department, School of
Medicine, Hospital das Clinicas, University of São Paulo, São Paulo ,
Brazil
| | - Nicole N Gaykova
- Medical Biodynamics Program,
Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Harvard
Medical School, Boston, MA, USA
| | - Men-Tzung Lo
- Institute of Translational and
Interdisciplinary Medicine and Department of Biomedical Sciences and
Engineering, National Central University, Taoyuan
| | - Ricardo C Nogueira
- Neurology Department, School of
Medicine, Hospital das Clinicas, University of São Paulo, São Paulo ,
Brazil
- Neurology Department, Hospital
Sirio Libanes, São Paulo, Brazil
| | - Kun Hu
- Medical Biodynamics Program,
Division of Sleep and Circadian Disorders, Brigham and Women’s Hospital, Harvard
Medical School, Boston, MA, USA
- Division of Sleep Medicine, Harvard
Medical School, Boston, MA, USA
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18
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Smail OJ, Clarke DJ, Al‐Alem Q, Wallis W, Barker AR, Smirl JD, Bond B. Resistance exercise acutely elevates dynamic cerebral autoregulation gain. Physiol Rep 2023; 11:e15676. [PMID: 37100594 PMCID: PMC10132945 DOI: 10.14814/phy2.15676] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/20/2023] [Accepted: 04/04/2023] [Indexed: 04/28/2023] Open
Abstract
Dynamic cerebral autoregulation (dCA) describes the regulation of cerebral blood flow (CBF) in response to fluctuations in systemic blood pressure (BP). Heavy resistance exercise is known to induce large transient elevations in BP, which are translated into perturbations of CBF, and may alter dCA in the immediate aftermath. This study aimed to better quantify the time course of any acute alterations in dCA after resistance exercise. Following familiarisation to all procedures, 22 (14 male) healthy young adults (22 ± 2 years) completed an experimental trial and resting control trial, in a counterbalanced order. Repeated squat-stand manoeuvres (SSM) at 0.05 and 0.10 Hz were used to quantify dCA before, and 10 and 45 min after four sets of ten repetition back squats at 70% of one repetition maximum, or time matched seated rest (control). Diastolic, mean and systolic dCA were quantified by transfer function analysis of BP (finger plethysmography) and middle cerebral artery blood velocity (transcranial Doppler ultrasound). Mean gain (p = 0.02; d = 0.36) systolic gain (p = 0.01; d = 0.55), mean normalised gain (p = 0.02; d = 0.28) and systolic normalised gain (p = 0.01; d = 0.67) were significantly elevated above baseline during 0.10 Hz SSM 10-min post resistance exercise. This alteration was not present 45 min post-exercise, and dCA indices were never altered during SSM at 0.05 Hz. dCA metrics were acutely altered 10 min post resistance exercise at the 0.10 Hz frequency only, which indicate changes in the sympathetic regulation of CBF. These alterations recovered 45 min post-exercise.
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Affiliation(s)
- Oliver J. Smail
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - Daniel J. Clarke
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - Qais Al‐Alem
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - William Wallis
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
| | - Alan R. Barker
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
- Children's Health and Exercise Research CentreUniversity of ExeterExeterUK
| | - Jonathan D. Smirl
- Faculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Reach InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
- Cerebrovascular Concussion LabUniversity of CalgaryCalgaryAlbertaCanada
| | - Bert Bond
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT), Public Health and Sport SciencesUniversity of ExeterExeterUK
- Children's Health and Exercise Research CentreUniversity of ExeterExeterUK
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19
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Panerai RB, Barnes SC, Batterham AP, Robinson TG, Haunton VJ. Directional sensitivity of dynamic cerebral autoregulation during spontaneous fluctuations in arterial blood pressure at rest. J Cereb Blood Flow Metab 2023; 43:552-564. [PMID: 36420777 PMCID: PMC10063834 DOI: 10.1177/0271678x221142527] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Directional sensitivity, the more efficient response of cerebral autoregulation to increases, compared to decreases, in mean arterial pressure (MAP), has been demonstrated with repeated squat-stand maneuvers (SSM). In 43 healthy subjects (26 male, 23.1 ± 4.2 years old), five min. recordings of cerebral blood velocity (bilateral Doppler ultrasound), MAP (Finometer), end-tidal CO2 (capnograph), and heart rate (ECG) were obtained during sitting (SIT), standing (STA) and SSM. A new analytical procedure, based on autoregressive-moving average models, allowed distinct estimates of the autoregulation index (ARI) by separating the MAP signal into its positive (MAP+D) and negative (MAP-D) derivatives. ARI+D was higher than ARI-D (p < 0.0001), SIT: 5.61 ± 1.58 vs 4.31 ± 2.16; STA: 5.70 ± 1.24 vs 4.63 ± 1.92; SSM: 4.70 ± 1.11 vs 3.31 ± 1.53, but the difference ARI+D-ARI-D was not influenced by the condition. A bootstrap procedure determined the critical number of subjects needed to identify a significant difference between ARI+D and ARI-D, corresponding to 24, 37 and 38 subjects, respectively, for SSM, STA and SIT. Further investigations are needed on the influences of sex, aging and other phenotypical characteristics on the phenomenon of directional sensitivity of dynamic autoregulation.
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Affiliation(s)
- Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Sam C Barnes
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Angus P Batterham
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK
| | - Thompson G Robinson
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
| | - Victoria J Haunton
- Department of Cardiovascular Sciences, University of Leicester, Leicester, UK.,NIHR Leicester Biomedical Research Centre, BHF Cardiovascular Research Centre, Glenfield Hospital, Leicester, UK
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20
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Burma JS, Rattana S, Johnson NE, Smirl JD. Do mean values tell the full story? Cardiac cycle and biological sex comparisons in temporally derived neurovascular coupling metrics. J Appl Physiol (1985) 2023; 134:426-443. [PMID: 36603050 DOI: 10.1152/japplphysiol.00170.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023] Open
Abstract
Previous reports have noted cerebrovascular regulation differs across the cardiac cycle, with greater regulation occurring within systole. However, this methodological notion has not been meticulously scrutinized during temporally deduced neurovascular coupling (NVC) metrics with additional respect to biological sex. Analyses of 111 healthy individuals (40 females/71 males) were performed where participants engaged in the "Where's Waldo?" paradigm. All NVC parameters were quantified in the posterior and middle cerebral arteries at 310 unique timepoints. Several individuals completed repeat testing which enabled for between-day (3 timepoints) and within-day (7 timepoints) reliability comparisons in 17 and 11 individuals, respectively. One-way analysis of variance compared NVC metrics between diastole, mean, and systole values, as well as differences between biological sexes. Greater absolute cerebral blood velocity (CBv; baseline and peak) and total activation (area under the curve) were noted within systole for both posterior cerebral artery (PCA; P < 0.001) and middle cerebral artery (MCA; P < 0.001) values; however, the relative percent increase in CBv was greater within diastole (P < 0.001). Females had an elevated diastolic and mean CBv and a greater diastolic cerebrovascular conductance (P < 0.050). No sex differences were present for systolic CBv measures and within parameters quantifying the NVC response (area under the curve/relative CBv increase) across the cardiac cycle (P > 0.072). Future investigations seeking to differentiate cerebral regulatory mechanisms between clinical populations may benefit by performing their analyses across the cardiac cycle, as certain pathogenesis may affect one aspect of the cardiac cycle independently. Minimal differences were noted between females and males for metrics characterizing the NVC response across the cardiac cycle.NEW & NOTEWORTHY Neurovascular coupling (NVC) studies commonly assess the mean cerebral hemodynamic response with little consideration for diastole, systole, and biological sex. Greater total activation expressed as the area under the curve was seen within systole compared with mean and diastole. Resting cerebral blood velocity sex differences were more prevalent during diastole when the cerebrovasculature was pressure-passive. Future studies should assess the NVC response across the cardiac cycle as it may help delineate the underlying pathophysiology of various clinical populations.
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Affiliation(s)
- Joel S Burma
- Faculty of Kinesiology, Cerebrovascular Concussion Lab, University of Calgary, Calgary, Alberta, Canada.,Faculty of Kinesiology, Sport Injury Prevention Research Centre, University of Calgary, Calgary, Alberta, Canada.,Faculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
| | - Selina Rattana
- Faculty of Kinesiology, Cerebrovascular Concussion Lab, University of Calgary, Calgary, Alberta, Canada
| | - Nathan E Johnson
- Faculty of Kinesiology, Cerebrovascular Concussion Lab, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Faculty of Kinesiology, Cerebrovascular Concussion Lab, University of Calgary, Calgary, Alberta, Canada.,Faculty of Kinesiology, Sport Injury Prevention Research Centre, University of Calgary, Calgary, Alberta, Canada.,Faculty of Kinesiology, Human Performance Laboratory, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada
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21
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Panerai RB, Brassard P, Burma JS, Castro P, Claassen JA, van Lieshout JJ, Liu J, Lucas SJ, Minhas JS, Mitsis GD, Nogueira RC, Ogoh S, Payne SJ, Rickards CA, Robertson AD, Rodrigues GD, Smirl JD, Simpson DM. Transfer function analysis of dynamic cerebral autoregulation: A CARNet white paper 2022 update. J Cereb Blood Flow Metab 2023; 43:3-25. [PMID: 35962478 PMCID: PMC9875346 DOI: 10.1177/0271678x221119760] [Citation(s) in RCA: 42] [Impact Index Per Article: 42.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Cerebral autoregulation (CA) refers to the control of cerebral tissue blood flow (CBF) in response to changes in perfusion pressure. Due to the challenges of measuring intracranial pressure, CA is often described as the relationship between mean arterial pressure (MAP) and CBF. Dynamic CA (dCA) can be assessed using multiple techniques, with transfer function analysis (TFA) being the most common. A 2016 white paper by members of an international Cerebrovascular Research Network (CARNet) that is focused on CA strove to improve TFA standardization by way of introducing data acquisition, analysis, and reporting guidelines. Since then, additional evidence has allowed for the improvement and refinement of the original recommendations, as well as for the inclusion of new guidelines to reflect recent advances in the field. This second edition of the white paper contains more robust, evidence-based recommendations, which have been expanded to address current streams of inquiry, including optimizing MAP variability, acquiring CBF estimates from alternative methods, estimating alternative dCA metrics, and incorporating dCA quantification into clinical trials. Implementation of these new and revised recommendations is important to improve the reliability and reproducibility of dCA studies, and to facilitate inter-institutional collaboration and the comparison of results between studies.
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Affiliation(s)
- Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester and NIHR Biomedical Research Centre, Leicester, UK
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, and Research Center of the Institut universitaire de cardiologie et de pneumologie de Québec, Université Laval, Québec, QC, Canada
| | - Joel S Burma
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - Pedro Castro
- Department of Neurology, Centro Hospitalar Universitário de São João, Faculty of Medicine, University of Porto, Porto, Portugal
| | - Jurgen Ahr Claassen
- Department of Geriatric Medicine and Donders Institute for Brain, Cognition and Behaviour, Radboud University, Nijmegen, The Netherlands
| | - Johannes J van Lieshout
- Department of Internal Medicine, Amsterdam, UMC, The Netherlands and Division of Physiology, Pharmacology and Neuroscience, School of Life Sciences, University of Nottingham Medical School, Queen's Medical Centre, UK
| | - Jia Liu
- Institute of Advanced Computing and Digital Engineering, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen University Town, Shenzhen, China
| | - Samuel Je Lucas
- School of Sport, Exercise and Rehabilitation Sciences and Centre for Human Brain Health, University of Birmingham, Birmingham, UK
| | - Jatinder S Minhas
- Department of Cardiovascular Sciences, University of Leicester and NIHR Biomedical Research Centre, Leicester, UK
| | - Georgios D Mitsis
- Department of Bioengineering, McGill University, Montreal, Québec, QC, Canada
| | - Ricardo C Nogueira
- Neurology Department, School of Medicine, Hospital das Clinicas, University of São Paulo, São Paulo, Brazil
| | - Shigehiko Ogoh
- Department of Biomedical Engineering, Toyo University, Kawagoe-Shi, Saitama, Japan
| | - Stephen J Payne
- Institute of Applied Mechanics, National Taiwan University, Taipei
| | - Caroline A Rickards
- Department of Physiology & Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, USA
| | - Andrew D Robertson
- Department of Kinesiology and Health Sciences, University of Waterloo, Waterloo, ON, Canada
| | - Gabriel D Rodrigues
- Department of Clinical Sciences and Community Health, University of Milan, Milan, Italy
| | - Jonathan D Smirl
- Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada
| | - David M Simpson
- Institute of Sound and Vibration Research, University of Southampton, Southampton, UK
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22
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Reed EL, Worley ML, Kueck PJ, Pietrafasa LD, Schlader ZJ, Johnson BD. Cerebral vascular function following the acute consumption of caffeinated artificially- and sugar sweetened soft drinks in healthy adults. Front Hum Neurosci 2022; 16:1063273. [PMID: 36618993 PMCID: PMC9815463 DOI: 10.3389/fnhum.2022.1063273] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2022] [Accepted: 11/30/2022] [Indexed: 12/24/2022] Open
Abstract
Chronic consumption of sugar- and artificially-sweetened beverages (SSB and ASB) are associated with an increased risk of stroke but it is unclear how acute consumption influences cerebral vascular function. Purpose: We hypothesized that: (1) acute consumption of SSB and ASB would augment dynamic cerebral autoregulation (dCA) and attenuate cerebral vascular reactivity to hypercapnia (CVRCO2) compared to water; and (2) dCA and CVRCO2 would be attenuated with SSB compared to ASB and water. Methods: Twelve healthy adults (age: 23 ± 2 years, four females) completed three randomized trials where they drank 500 ml of water, SSB (Mountain Dew®), or ASB (Diet Mountain Dew®). We measured mean arterial pressure (MAP), middle and posterior cerebral artery blood velocities (MCAv and PCAv), and end-tidal CO2 tension (PETCO2). Cerebral vascular conductance was calculated as cerebral artery blood velocity/MAP (MCAc and PCAc). Twenty min after consumption, participants completed a 5 min baseline, and in a counterbalanced order, a CVRCO2 test (3%, 5%, and 7% CO2 in 3 min stages) and a dCA test (squat-stand tests at 0.10 Hz and 0.05 Hz for 5 min each) separated by 10 min. CVRCO2 was calculated as the slope of the linear regression lines of MCAv and PCAv vs. PETCO2. dCA was assessed in the MCA using transfer function analysis. Coherence, gain, and phase were determined in the low frequency (LF; 0.07-0.2 Hz) and very low frequency (VLF; 0.02-0.07 Hz). Results: MCAv and MCAc were lower after SSB (54.11 ± 12.28 cm/s, 0.58 ± 0.15 cm/s/mmHg) and ASB (51.07 ± 9.35 cm/s, 0.52 ± 1.0 cm/s/mmHg) vs. water (62.73 ± 12.96 cm/s, 0.67 ± 0.11 cm/s/mmHg; all P < 0.035), respectively. PCAc was also lower with the ASB compared to water (P = 0.007). MCA CVRCO2 was lower following ASB (1.55 ± 0.38 cm/s/mmHg) vs. water (2.00 ± 0.57 cm/s/mmHg; P = 0.011) but not after SSB (1.90 ± 0.67 cm/s/mmHg; P = 0.593). PCA CVRCO2 did not differ between beverages (P > 0.853). There were no differences between beverages for coherence (P ≥ 0.295), gain (P ≥ 0.058), or phase (P ≥ 0.084) for either frequency. Discussion: Acute consumption of caffeinated SSB and ASB resulted in lower intracranial artery blood velocity and conductance but had a minimal effect on cerebral vascular function as only MCA CVRCO2 was altered with the ASB compared to water.
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Affiliation(s)
- Emma L. Reed
- Human Integrative Physiology Lab, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, United States
| | - Morgan L. Worley
- Human Integrative Physiology Lab, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, United States
| | - Paul J. Kueck
- Human Integrative Physiology Lab, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, United States
| | - Leonard D. Pietrafasa
- Human Integrative Physiology Lab, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, United States
| | - Zachary J. Schlader
- H.H. Morris Human Performance Laboratories, Department of Kinesiology, Indiana University, Bloomington, IN, United States
| | - Blair D. Johnson
- Human Integrative Physiology Lab, Department of Exercise and Nutrition Sciences, University at Buffalo, Buffalo, NY, United States,H.H. Morris Human Performance Laboratories, Department of Kinesiology, Indiana University, Bloomington, IN, United States,*Correspondence: Blair D. Johnson
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23
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Validity of transcranial Doppler ultrasonography-determined dynamic cerebral autoregulation estimated using transfer function analysis. J Clin Monit Comput 2022; 36:1711-1721. [PMID: 35075510 DOI: 10.1007/s10877-022-00817-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Accepted: 01/19/2022] [Indexed: 10/19/2022]
Abstract
Transcranial Doppler ultrasonography (TCD) is used widely to evaluate dynamic cerebral autoregulation (dCA). However, the validity of TCD-determined dCA remains unknown because TCD is only capable of measuring blood velocity and thus only provides an index as opposed to true blood flow. To test the validity of TCD-determined dCA, in nine healthy subjects, dCA was evaluated by transfer function analysis (TFA) using cerebral blood flow (CBF) or TCD-measured cerebral blood velocity during a perturbation that induces reductions in TCD-determined dCA, lower body negative pressure (LBNP) at two different stages: LBNP - 15 mmHg and - 50 mmHg. Internal carotid artery blood flow (ICA Q) was assessed as an index of CBF using duplex Doppler ultrasound. The TFA low frequency (LF) normalized gain (ngain) calculated using ICA Q increased during LBNP at - 50 mmHg (LBNP50) from rest (P = 0.005) and LBNP at - 15 mmHg (LBNP15) (P = 0.015), indicating an impaired dCA. These responses were the same as those obtained using TCD-measured cerebral blood velocity (from rest and LBNP15; P = 0.001 and P = 0.015). In addition, the ICA Q-determined TFA LF ngain from rest to LBNP50 was significantly correlated with TCD-determined TFA LF ngain (r = 0.460, P = 0.016) despite a low intraclass correlation coefficient. Moreover, in the Bland-Altman analysis, the difference in the TFA LF ngains determined by blood flow and velocity was within the margin of error, indicating that the two measurement methods can be interpreted as equivalent. These findings suggest that TCD-determined dCA can be representative of actual dCA evaluated with CBF.
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24
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Jack J, Woodgates A, Smail O, Brown F, Lynam K, Lester A, Williams G, Bond B. Cerebral blood flow regulation is not acutely altered after a typical number of headers in women footballers. Front Neurol 2022; 13:1021536. [PMID: 36479047 PMCID: PMC9719992 DOI: 10.3389/fneur.2022.1021536] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2022] [Accepted: 10/31/2022] [Indexed: 09/29/2023] Open
Abstract
BACKGROUND The repeated act of heading has been implicated in the link between football participation and risk of neurodegenerative disease, and acutely alters cerebrovascular outcomes in men. This study assessed whether exposure to a realistic number of headers acutely influences indices of cerebral blood flow regulation in female footballers. METHODS Nineteen female players completed a heading trial and seated control trial on two separate days. The heading trial involved six headers in 1 h (one every 10 min), with the ball traveling at 40 ± 5 km/h. Cerebrovascular reactivity to hypercapnia and hypocapnia was determined using serial breath holding and hyperventilation attempts. Dynamic cerebral autoregulation (dCA) was assessed by scrutinizing the relationship between cerebral blood flow and mean arterial blood pressure during 5 min of squat stand maneuvers at 0.05 Hz. Neurovascular coupling (NVC) was quantified as the posterior cerebral artery blood velocity response to a visual search task. These outcomes were assessed before and 1 h after the heading or control trial. RESULTS No significant time by trial interaction was present for the hypercapnic (P = 0.48,η p 2 = 0.05) and hypocapnic (P = 0.47,η p 2 = 0.06) challenge. Similarly, no significant interaction effect was present for any metric of dCA (P > 0.12,η p 2 < 0.16 for all) or NVC (P > 0.14,η p 2 < 0.15 for all). CONCLUSION The cerebral blood flow response to changes in carbon dioxide, blood pressure and a visual search task were not altered following six headers in female footballers. Further study is needed to observe whether changes are apparent after more prolonged exposure.
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Affiliation(s)
| | | | | | | | | | | | | | - Bert Bond
- Exeter Head Impacts, Brain Injury and Trauma (ExHIBIT) Research Group, Sport and Health Sciences, University of Exeter, Exeter, United Kingdom
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25
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Sirant LW, Singh J, Martin S, Gaul CA, Stuart-Hill L, Candow DG, Mang C, Neary JP. Long-term effects of multiple concussions on prefrontal cortex oxygenation during neurovascular coupling activation in retired male contact sport athletes. Curr Res Physiol 2022; 5:421-428. [DOI: 10.1016/j.crphys.2022.11.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Revised: 11/20/2022] [Accepted: 11/22/2022] [Indexed: 11/26/2022] Open
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26
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Burma JS, Van Roessel RK, Oni IK, Dunn JF, Smirl JD. Neurovascular coupling on trial: How the number of trials completed impacts the accuracy and precision of temporally derived neurovascular coupling estimates. J Cereb Blood Flow Metab 2022; 42:1478-1492. [PMID: 35209741 PMCID: PMC9274868 DOI: 10.1177/0271678x221084400] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Standard practices for quantifying neurovascular coupling (NVC) with transcranial Doppler ultrasound (TCD) require participants to complete one-to-ten repetitive trials. However, limited empirical evidence exists regarding how the number of trials completed influences the validity and reliability of temporally derived NVC metrics. Secondary analyses was performed on 60 young healthy participants (30 females/30 males) who completed eight cyclical eyes-closed (20-seconds), eyes-open (40-seconds) NVC trials, using the "Where's Waldo?" visual paradigm. TCD data was obtained in posterior and middle cerebral arteries (PCA and MCA, respectively). The within-day (n = 11) and between-day (n = 17) reliability were assessed at seven- and three-time points, respectively. Repeat testing from the reliability aims were also used for the concurrent validity analysis (n = 160). PCA metrics (i.e., baseline, peak, percent increase, and area-under-the-curve) demonstrated five trials produced excellent intraclass correlation coefficient (ICC) 95% confidence intervals for validity and within-day reliability (>0.900), whereas between-day reliability was good-to-excellent (>0.750). Likewise, 95% confidence intervals for coefficient of variation (CoV) measures ranged from acceptable (<20%) to excellent (<5%) with five-or-more trials. Employing fewer than five trials produced poor/unacceptable ICC and CoV metrics. Future NVC, TCD-based research should therefore have participants complete a minimum of five trials when quantifying the NVC response with TCD via a "Where's Waldo?" paradigm.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Rowan K Van Roessel
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada
| | - Ibukunoluwa K Oni
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jeff F Dunn
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada.,Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
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27
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Skow RJ, Brothers RM, Claassen JAHR, Day TA, Rickards CA, Smirl JD, Brassard P. On the use and misuse of cerebral hemodynamics terminology using Transcranial Doppler ultrasound: a call for standardization. Am J Physiol Heart Circ Physiol 2022; 323:H350-H357. [PMID: 35839156 DOI: 10.1152/ajpheart.00107.2022] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Cerebral hemodynamics (e.g., cerebral blood flow) can be measured and quantified using many different methods, with Transcranial Doppler ultrasound (TCD) being one of the most commonly utilized approaches. In human physiology, the terminology used to describe metrics of cerebral hemodynamics are inconsistent, and in some instances technically inaccurate; this is especially true when evaluating, reporting, and interpreting measures from TCD. Therefore, this perspectives article presents recommended terminology when reporting cerebral hemodynamic data. We discuss the current use and misuse of the terminology in the context of using TCD to measure and quantify cerebral hemodynamics and present our rationale and consensus on the terminology that we recommend moving forward. For example, one recommendation is to discontinue use of the term "cerebral blood flow velocity" in favor of "cerebral blood velocity" with precise indication of the vessel of interest. We also recommend clarity when differentiating between discrete cerebrovascular regulatory mechanisms, namely cerebral autoregulation, neurovascular coupling, and cerebrovascular reactivity. This will be a useful guide for investigators in the field of cerebral hemodynamics research.
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Affiliation(s)
- Rachel J Skow
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, United States
| | - R Matthew Brothers
- Department of Kinesiology, The University of Texas at Arlington, Arlington, TX, United States
| | - Jurgen A H R Claassen
- Department of Geriatrics, Radboud University Medical Center, Nijmegen, The Netherlands
| | - Trevor A Day
- Department of Biology, Faculty of Science and Technology, Mount Royal University, Calgary, Alberta, Canada
| | - Caroline A Rickards
- Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas, United States
| | - Jonathan D Smirl
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Canada
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28
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Does Hypnotizability Affect Neurovascular Coupling During Cognitive Tasks? Physiol Behav 2022; 257:113915. [PMID: 35843420 DOI: 10.1016/j.physbeh.2022.113915] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Revised: 07/09/2022] [Accepted: 07/11/2022] [Indexed: 11/22/2022]
Abstract
The susceptibility to hypnosis is a very pervasive psychophysiological trait characterized by different attentional abilities, information processing, and cardiovascular control. Since near infrared spectroscopy (NIRS) is a good index of neurovascular coupling, we used it during mental computation (MC) and trail making task (TMT) in 13 healthy low-to-medium (med-lows) and 10 healthy medium-to-high hypnotizable (med-highs) participants classified according to the Stanford Hypnotic Susceptibility Scale (SHSS), form A, and characterized for the level of proneness to be deeply absorbed in cognitive tasks by the Tellegen Absorption Scale (TAS). Med-highs reported greater absorption than med-lows. The tissue hemoglobin index (THI) and the tissue oxygenation index (TOI) increased across the tasks only in med-highs who displayed also different time courses of THI and TOI during MC and TMT, which indicates different tasks processing despite the two groups' similar performance. The findings suggest that the med-highs' tissue oxygenation is more finely adjusted to metabolic demands than med-lows'.
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29
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Pereira TJ, Wasef S, Ivry I, Assadpour E, Adeyinka B, Edgell H. Menstrual cycle and oral contraceptives influence cerebrovascular dynamics during hypercapnia. Physiol Rep 2022; 10:e15373. [PMID: 35822289 PMCID: PMC9277257 DOI: 10.14814/phy2.15373] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Accepted: 06/10/2022] [Indexed: 06/15/2023] Open
Abstract
Women experience fluctuating orthostatic intolerance during the menstrual cycle, suggesting sex hormones may influence cerebral blood flow. Young (aged 18-30) healthy women, either taking oral contraceptives (OC; n = 14) or not taking OC (NOC; n = 12), were administered hypercapnic gas (5%) for 5 min in the low hormone (LH; placebo pill) and high hormone (HH; active pill) menstrual phases. Hemodynamic and cerebrovascular variables were continuously measured. Cerebral blood velocity changes were monitored using transcranial doppler ultrasound of the middle cerebral artery to determine cerebrovascular reactivity. Cerebral autoregulation was assessed using steady-state analysis (static cerebral autoregulation) and transfer function analysis (dynamic cerebral autoregulation; dCA). In response to hypercapnia, menstrual phase did not influence static cardiovascular or cerebrovascular responses (all p > 0.07); however, OC users had a greater increase of mean middle cerebral artery blood velocity compared to NOC (NOC-LH 12 ± 6 cm/s vs. NOC-HH 16 ± 9 cm/s; OC-LH 18 ± 5 cm/s vs. OC-HH 17 ± 11 cm/s; p = 0.048). In all women, hypercapnia improved high frequency (HF) and very low frequency (VLF) cerebral autoregulation (decreased nGain; p = 0.002 and <0.001, respectively), whereas low frequency (LF) Phase decreased in NOC-HH (p = 0.001) and OC-LH (p = 0.004). Therefore, endogenous sex hormones reduce LF dCA during hypercapnia in the HH menstrual phase. In contrast, pharmaceutical sex hormones (OC use) have no acute influence (HH menstrual phase) yet elicit a chronic attenuation of LF dCA (LH menstrual phase) during hypercapnia.
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Affiliation(s)
- Tania J. Pereira
- School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada
| | - Sara Wasef
- School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada
| | - Ilana Ivry
- School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada
| | - Elnaz Assadpour
- School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada
| | | | - Heather Edgell
- School of Kinesiology and Health ScienceYork UniversityTorontoOntarioCanada
- Muscle Health Research CentreYork UniversityTorontoOntarioCanada
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30
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Kennedy CM, Burma JS, Newel KT, Brassard P, Smirl JD. Time course recovery of cerebral blood velocity metrics post aerobic exercise: A systematic review. J Appl Physiol (1985) 2022; 133:471-489. [PMID: 35708702 DOI: 10.1152/japplphysiol.00630.2021] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Currently, the standard approach for restricting exercise prior to cerebrovascular data collection varies widely between 6-24 hours. This universally employed practice is a conservative approach to safeguard physiological alterations that could potentially confound one's study design. Therefore, the purpose of this systematic review was to amalgamate the literature that examines the extent and duration cerebrovascular function is impacted following aerobic exercise measured via transcranial Doppler ultrasound. Further, an exploratory aim was to scrutinize and discuss common biases/limitations in the previous studies to help guide future investigations. Search strategies were developed and imported into PubMed, SPORTDiscus, and Medline databases. A total of 595 records were screened and 35 articles met the inclusion criteria in this review, which included assessments of basic cerebrovascular metrics (n=35), dynamic cerebral autoregulation (dCA; n=9), neurovascular coupling (NVC; n=2); and/or cerebrovascular reactivity (CVR-CO2; n=1) following acute bouts of aerobic exercise. Across all studies, it was found NVC was impacted for 1-hour, basic cerebrovascular parameters and CVR-CO2 parameters 2-hours, and dCA metrics 6-hours post-exercise. Therefore, future studies can provide participants with these evidence-based time restrictions, regarding the minimum time to abstain from exercise prior to data collection. However, it should be noted, other physiological mechanisms could still be altered (e.g., metabolic, hormonal, and/or autonomic influences), despite cerebrovascular function returning to baseline levels. Thus, future investigations should seek to control for as many physiological influences when employing cerebrovascular assessments, immediately following these time restraints. The main limitations/biases were lack of female participants, cardiorespiratory fitness, and consideration for vessel diameter.
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Affiliation(s)
- Courtney M Kennedy
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
| | - Joel S Burma
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
| | - Kailey T Newel
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Patrice Brassard
- Department of Kinesiology, Université Laval, Québec, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Québec, Canada
| | - Jonathan David Smirl
- Cerebrovascular Concussion Lab, Faculty of Kinesiology, University of Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
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Newel KT, Burma JS, Carere J, Kennedy C, Smirl JD. Does oscillation size matter? Impact of added resistance on the cerebral pressure-flow Relationship in females and males. Physiol Rep 2022; 10:e15278. [PMID: 35581899 PMCID: PMC9114660 DOI: 10.14814/phy2.15278] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2022] [Accepted: 04/05/2022] [Indexed: 11/24/2022] Open
Abstract
Sinusoidal squat-stand maneuvers (SSM) without resistance have been shown to produce ~30-50 mmHg swings in mean arterial pressure which are largely buffered in the brain via dynamic cerebral autoregulation (dCA). This study aimed to further elucidate how this regulatory mechanism is affected during SSM with added resistance (~20% bodyweight). Twenty-five participants (sex/gender: 13 females/12 males) completed two bouts of 5-min SSM for both bodyweight and resistance conditions (10% bodyweight in each arm) at frequencies of 0.05 Hz (20-s squat/stand cycles) and 0.10 Hz (10-s squat/stand cycles). Middle and posterior cerebral artery (MCA/PCA) cerebral blood velocities were indexed with transcranial Doppler ultrasound. Beat-to-beat blood pressure (BP) was quantified via finger photoplesmography. Transfer function analysis was employed to quantify dCA in both cerebral arteries across the cardiac cycle (diastole, mean, and systole). Two-by-two Analysis of Variance with generalized eta squared effect sizes were utilized to determine differences between resistance vs. bodyweight squats and between sexes/genders. Absolute mean and diastolic BP were elevated during the resistance squats (p < 0.001); however, only the BP point-estimate power spectrum densities were augmented at 0.10 Hz (p < 0.048). No differences were noted for phase and gain metrics between bodyweight and resistance SSM (p > 0.067); however, females displayed attenuated systolic regulation (p < 0.003). Despite augmented systemic BP during resistance SSM, the brain was effective at buffering the additional stress to mitigate overperfusion/pressure. Females displayed less dCA regulation within the systolic aspect of the cardiac cycle, which may be associated with physiological underpinnings related to various clinical conditions/presentations.
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Affiliation(s)
- Kailey T. Newel
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Faculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBritish ColumbiaCanada
| | - Joel S. Burma
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Joseph Carere
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Courtney M. Kennedy
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Jonathan D. Smirl
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryAlbertaCanada
- Alberta Children's Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
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32
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Cerebral Blood Flow in Healthy Subjects with Different Hypnotizability Scores. Brain Sci 2022; 12:brainsci12050558. [PMID: 35624945 PMCID: PMC9138886 DOI: 10.3390/brainsci12050558] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Revised: 04/11/2022] [Accepted: 04/26/2022] [Indexed: 12/19/2022] Open
Abstract
Hypnotizability is a cognitive trait associated with differences in the brachial artery flow-mediated dilatation of individuals with high hypnotizability (highs) and low hypnotizability scores (lows). The study investigated possible hypnotizability-related cerebrovascular differences. Among 24 healthy volunteers, the Stanford Hypnotic Susceptibility Scale Form A identified 13 medium-to-lows (med-lows), 11 medium-to-highs (med-highs), and 1 medium hypnotizable. Hypnotizability did not influence the significant changes produced by the trail making task (TMT), mental arithmetic task (MAT), hyperventilation (HVT), and rebreathing (RBT) on heart rate (HR), arterial blood pressure (ABP), and partial pressure of end-tidal CO2 (PETCO2), but moderated the correlations between the changes occurring during tasks with respect to basal conditions (Δ) in ABP and PETCO2 with middle cerebral artery flow velocity (MCAv). In HVT, med-lows exhibited a significant correlation between ΔMCAv and ΔPETCO2, and med-highs showed a significant correlation between ΔABP and ΔMCAv. Cerebrovascular reactivity (CVR) and conductance (ΔCVCi) were significantly correlated with ΔMCAv only in med-lows during HVT and RBT. For the first time, cerebrovascular reactivity related to hypnotizability was investigated, evidencing different correlations among hemodynamic variables in med-highs and med-lows.
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Maxwell JD, Bannell DJ, Brislane A, Carter SE, Miller GD, Roberts KA, Hopkins ND, Low DA, Carter HH, Thompson A, Claassen JAHR, Thijssen DHJ, Jones H. The impact of age, sex, cardio-respiratory fitness, and cardiovascular disease risk on dynamic cerebral autoregulation and baroreflex sensitivity. Eur J Appl Physiol 2022; 122:1531-1541. [PMID: 35429292 PMCID: PMC9132800 DOI: 10.1007/s00421-022-04933-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/03/2020] [Accepted: 03/08/2022] [Indexed: 11/10/2022]
Abstract
Background Humans display an age-related decline in cerebral blood flow and increase in blood pressure (BP), but changes in the underlying control mechanisms across the lifespan are less well understood. We aimed to; (1) examine the impact of age, sex, cardiovascular disease (CVD) risk, and cardio-respiratory fitness on dynamic cerebral autoregulation and cardiac baroreflex sensitivity, and (2) explore the relationships between dynamic cerebral autoregulation (dCA) and cardiac baroreflex sensitivity (cBRS). Methods 206 participants aged 18–70 years were stratified into age categories. Cerebral blood flow velocity was measured using transcranial Doppler ultrasound. Repeated squat-stand manoeuvres were performed (0.10 Hz), and transfer function analysis was used to assess dCA and cBRS. Multivariable linear regression was used to examine the influence of age, sex, CVD risk, and cardio-respiratory fitness on dCA and cBRS. Linear models determined the relationship between dCA and cBRS. Results Age, sex, CVD risk, and cardio-respiratory fitness did not impact dCA normalised gain, phase, or coherence with minimal change in all models (P > 0.05). cBRS gain was attenuated with age when adjusted for sex and CVD risk (young–older; β = − 2.86 P < 0.001) along with cBRS phase (young–older; β = − 0.44, P < 0.001). There was no correlation between dCA normalised gain and phase with either parameter of cBRS. Conclusion Ageing was associated with a decreased cBRS, but dCA appears to remain unchanged. Additionally, our data suggest that sex, CVD risk, and cardio-respiratory fitness have little effect.
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Carere J, Burma JS, Newel KT, Kennedy CM, Smirl JD. Sex differences in autonomic recovery following repeated sinusoidal resistance exercise. Physiol Rep 2022; 10:e15269. [PMID: 35466556 PMCID: PMC9035755 DOI: 10.14814/phy2.15269] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2022] [Revised: 03/28/2022] [Accepted: 03/31/2022] [Indexed: 06/14/2023] Open
Abstract
A simple bodyweight squat is sufficient to cause substantial stress on the autonomic nervous system (ANS) via ~30-50 mmHg blood pressure (BP) oscillations. However, it is unknown to the extent of the ANS is impacted during and immediately following bodyweight and resistance squat-stand maneuvers (SSM) while considering chromosomal sex. Thirteen females and twelve males performed four, 5-minute bouts of squat-stand maneuvers (SSM); two at 0.05 Hz (10-second squat/10-second stand) and two at 0.10 Hz (5-s squat/5-s stand). The SSM were performed using bodyweight resistance and additional external resistance (~20% of bodyweight). Five-minutes of quiet-sitting and quiet-standing were completed immediately following both bodyweight and resistance squats. Heart rate variability (HRV) and baroreceptor sensitivity metrics were extracted from beat-to-beat electrocardiography and systemic BP recordings. Repeated measure Analysis of Variance with generalized eta-squared effect sizes assessed differences between SSM task type and chromosomal sex on ANS metrics. Despite added resistance eliciting greater elevations in blood pressure, no differences in ANS function were noted during competition and recovery between SSM tasks (all p > 0.050; negligible/small effect sizes). During recovery, females had an elevated heart rate (p = 0.017; small effect size), greater time-domain HRV measures (p < 0.047; small effect size), greater high-frequency domain HRV measures (p = 0.002; moderate effect size), and reduced low-frequency domain HRV measures (p = 0.002; moderate effect size). A healthy ANS can modulate repetitive cardiovascular stressors via squat-stand maneuvers in a harmonious manner irrespective of added low-level resistance. Females were more parasympathetically driven following low-level resistance exercise/stress, which may be a cardioprotective trait.
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Affiliation(s)
- Joseph Carere
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Joel S. Burma
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Kailey T. Newel
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Faculty of Health and Exercise ScienceUniversity of British ColumbiaKelownaBritish ColumbiaCanada
| | - Courtney M. Kennedy
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
| | - Jonathan D. Smirl
- Cerebrovascular Concussion LabFaculty of KinesiologyUniversity of CalgaryAlbertaCanada
- Sport Injury Prevention Research CentreFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Hotchkiss Brain InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Integrated Concussion Research ProgramUniversity of CalgaryCalgaryABCanada
- Alberta Children’s Hospital Research InstituteUniversity of CalgaryCalgaryAlbertaCanada
- Human Performance LaboratoryFaculty of KinesiologyUniversity of CalgaryCalgaryAlbertaCanada
- Libin Cardiovascular Institute of AlbertaUniversity of CalgaryAlbertaCanada
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35
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Roy MA, Labrecque L, Perry BG, Korad S, Smirl JD, Brassard P. Directional sensitivity of the cerebral pressure-flow relationship in young healthy individuals trained in endurance and resistance exercise. Exp Physiol 2022; 107:299-311. [PMID: 35213765 DOI: 10.1113/ep090159] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 02/08/2022] [Indexed: 11/08/2022]
Abstract
NEW FINDINGS What is the central question of this study? Does habitual exercise modality affect the directionality of the cerebral pressure-flow relationship? What is the main finding and its importance? These data suggest the hysteresis-like pattern of dynamic cerebral autoregulation appears present in long-term sedentary and endurance-trained individuals, but absent in resistance-trained individuals. This is the first study to expand knowledge on the directional sensitivity of the cerebral pressure-flow relationship to trained populations. ABSTRACT Evidence suggests the cerebrovasculature may be more efficient at dampening cerebral blood flow (CBF) variations when mean arterial pressure (MAP) transiently increases, compared to when it decreases. Despite divergent MAP and CBF responses to acute endurance and resistance training, the long-term impact of habitual exercise modality on the directionality of dynamic cerebral autoregulation (dCA) is currently unknown. Thirty-six young healthy participants [sedentary (n = 12), endurance-trained (n = 12) and resistance-trained (n = 12)] undertook a 5-min repeated squat-stand protocol at two forced MAP oscillation frequencies (0.05 Hz and 0.10 Hz). Middle cerebral artery mean blood velocity (MCAv) and MAP were continuously monitored. We calculated absolute (ΔMCAvT /ΔMAPT ) and relative (%MCAvT /%MAPT ) changes in MCAv and MAP with respect to the transition time intervals of both variables to compute a time-adjusted ratio in each MAP direction, averaged over the 5-min repeated squat-stand protocols. At 0.10 Hz repeated squat-stands, ΔMCAvT /ΔMAPT and %MCAvT /%MAPT were lower when MAP increased compared with when MAP decreased for sedentary (ΔMCAvT /ΔMAPT : p = 0.032; %MCAvT /%MAPT : p = 0.040) and endurance-trained individuals (ΔMCAvT /ΔMAPT : p = 0.012; %MCAvT /%MAPT : p = 0.007), but not in the resistance-trained (ΔMCAvT /ΔMAPT : p = 0.512; %MCAvT /%MAPT : p = 0.666). At 0.05 Hz repeated squat-stands, time-adjusted ratios were similar for all groups (all p>0.605). These findings suggest exercise training modality does influence the directionality of the cerebral pressure-flow relationship and support the presence of a hysteresis-like pattern during 0.10 Hz repeated squat-stands in sedentary and endurance-trained participants, but not in resistance-trained individuals. In future studies, assessment of elite endurance and resistance training habits may further elucidate modality-dependent discrepancies on directional dCA measurements. This article is protected by copyright. All rights reserved.
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Affiliation(s)
- Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Blake G Perry
- School of Health Sciences, Massey University, Wellington, New Zealand.,School of Sport, Exercise and Nutrition, Massey University, Wellington, New Zealand
| | - Stephanie Korad
- School of Health Sciences, Massey University, Wellington, New Zealand.,School of Sport, Exercise and Nutrition, Massey University, Wellington, New Zealand
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
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An acute bout of controlled subconcussive impacts can alter dynamic cerebral autoregulation indices: a preliminary investigation. Eur J Appl Physiol 2022; 122:1059-1070. [PMID: 35171333 DOI: 10.1007/s00421-022-04908-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Accepted: 02/01/2022] [Indexed: 11/03/2022]
Abstract
OBJECTIVES There is growing concern repetitive head contacts sustained by soccer players may lead to long-term health ramifications. Therefore, this preliminary investigation examined the impact an acute soccer heading bout has on dynamic cerebral autoregulation (dCA) metrics. METHODS In this preliminary investigation, 40 successful soccer headers were performed in 20 min by 7 male elite soccer players (24.1 ± 1.5 years). Soccer balls were launched at 77.5 ± 3.7 km/h from JUGS soccer machine, located 35 m away from participants. Linear and rotational head accelerations impacts were measured using an accelerometer (xPatch). The SCAT3 indexed concussion symptom score and severity before and after: soccer headers, sham (body contact only), and control conditions. Squat-stand maneuvers were performed at 0.05 Hz and 0.10 Hz to quantity dCA through measures of coherence, phase, and gain. RESULTS Cumulative linear and rotational accelerations during soccer headers were 1574 ± 97.9 g and 313,761 ± 23,966 rads/s2, respectively. SCAT3 symptom severity was elevated after the soccer heading bout (pre 3.7 ± 3.6, post 9.4 ± 7.6: p = 0.030) and five of the seven participants reported an increase in concussion-like symptoms (pre: 2.6 ± 3.0, post: 6.7 ± 6.2; p = 0.078). Phase at 0.10 Hz was elevated following soccer heading (p = 0.008). No other dCA metric differed following the three conditions. CONCLUSION These preliminary results indicate an acute bout of soccer heading resulted in alterations to dCA metrics. Therefore, future research with larger sample sizes is warranted to fully comprehend short- and long-term physiological changes related to soccer heading.
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Marullo AL, Bruce CD, Pfoh JR, Chauhan UV, Abrosimova M, Berg ERV, Skow RJ, Davenport MH, Strzalkowski NDJ, Steinback CD, Day TA. Cerebrovascular and blood pressure responses during voluntary apneas are larger than rebreathing. Eur J Appl Physiol 2022; 122:735-743. [PMID: 34978604 DOI: 10.1007/s00421-021-04864-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2021] [Accepted: 11/29/2021] [Indexed: 11/03/2022]
Abstract
Both voluntary rebreathing (RB) of expired air and voluntary apneas (VA) elicit changes in arterial carbon dioxide and oxygen (CO2 and O2) chemostimuli. These chemostimuli elicit synergistic increases in cerebral blood flow (CBF) and sympathetic nervous system activation, with the latter increasing systemic blood pressure. The extent that simultaneous and inverse changes in arterial CO2 and O2 and associated increases in blood pressure affect the CBF responses during RB versus VAs are unclear. We instrumented 21 healthy participants with a finometer (beat-by-beat mean arterial blood pressure; MAP), transcranial Doppler ultrasound (middle and posterior cerebral artery velocity; MCAv, PCAv) and a mouthpiece with sample line attached to a dual gas analyzer to assess pressure of end-tidal (PET)CO2 and PETO2. Participants performed two protocols: RB and a maximal end-inspiratory VA. A second-by-second stimulus index (SI) was calculated as PETCO2/PETO2 during RB. For VA, where PETCO2 and PETO2 could not be measured throughout, SI values were calculated using interpolated end-tidal gas values before and at the end of the apneas. MAP reactivity (MAPR) was calculated as the slope of the MAP/SI, and cerebrovascular reactivity (CVR) was calculated as the slope of MCAv or PCAv/SI. We found that compared to RB, VA elicited ~ fourfold increases in MAPR slope (P < 0.001), translating to larger anterior and posterior CVR (P ≤ 0.01). However, cerebrovascular conductance (MCAv or PCAv/MAP) was unchanged between interventions (P ≥ 0.2). MAP responses during VAs are larger than those during RB across similar chemostimuli, and differential CVR may be driven by increases in perfusion pressure.
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Affiliation(s)
- Anthony L Marullo
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Christina D Bruce
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Jamie R Pfoh
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Uday V Chauhan
- Faculty of Kinesiology, Sport and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Maria Abrosimova
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Emily R Vanden Berg
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Rachel J Skow
- Faculty of Kinesiology, Sport and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Margie H Davenport
- Faculty of Kinesiology, Sport and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Nicholas D J Strzalkowski
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada
| | - Craig D Steinback
- Faculty of Kinesiology, Sport and Recreation, University of Alberta, Edmonton, AB, Canada
| | - Trevor A Day
- Department of Biology, Faculty of Science and Technology, Mount Royal University, 4825 Mount Royal Gate SW, Calgary, AB, T3E 6K6, Canada.
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Ellingson CJ, Singh J, Ellingson CA, Dech R, Piskorski J, Neary JP. The influence of external stressors on physiological testing: Implication for return-to-play protocols. Curr Res Physiol 2022; 5:240-245. [PMID: 35756694 PMCID: PMC9213225 DOI: 10.1016/j.crphys.2022.06.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Revised: 06/03/2022] [Accepted: 06/10/2022] [Indexed: 11/29/2022] Open
Abstract
External stressors such as alcohol, caffeine, and vigorous exercise are known to alter cellular homeostasis, affecting the autonomic nervous system (ANS) and overall physiological function. However, little direct evidence exists quantifying the impact of these external stressors on physiological testing. We assessed the impact of the above-listed stressors on spontaneous baroreflex sensitivity (BRS), heart rate variability (HRV), heart rate asymmetry (HRA), and systolic blood pressure variability (BPV). Seventeen male university varsity American-style football athletes completed two identical assessments on separate days, once presenting with one or more stressors (recent intake of caffeine, alcohol, or exercise participation; contraindicated assessment) and another with no stressors present (repeat assessment). Both assessments were conducted within one week and at the same time of day. The testing protocol consisted of 5-min of rest followed by 5-min of a squat-stand maneuver (0.05 Hz). Continuous beat-to-beat blood pressure and electrocardiogram measurements were collected and allowed for calculations of BRS, HRV, HRA, and BPV. Significant decreases (p < 0.05) in HRV and HRA metrics (SDNN, SD2, SDNNd, SDNNa, SD2a, SD2d), HRV total power, and BRS-up sequence were found during the contraindicated assessment in comparison to the repeat assessment. When assessing those with exercise as their only stressor, high-frequency HRV and BRS-pooled were significantly decreased and increased, respectively, during the contraindicated assessment. Pre-season physiological baseline testing in sport is becoming increasingly prevalent and thus must consider external stressors to ascertain accurate and reliable data. This data confirms the need for stringent and standardized guidelines for pre-participation baseline physiological testing. External stressors (exercise participation, caffeine consumption, and alcohol consumption) decrease heart rate variability and the asymmetrical contribution of heart rate accelerations and decelerations (SDNN, SD2, Total Power, SDNNd, SDNNa, SD2d, and SD2a). External stressors decrease spontaneous baroreflex sensitivity up-sequence, but no significant changes were found regarding systolic blood pressure variability. The establishment of standardized pre-participation guidelines controlling for external stressors would increase the validity and reliability of physiological testing, improving the clinical utility of such data.
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Affiliation(s)
- Chase J. Ellingson
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK, Canada
| | - Jyotpal Singh
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK, Canada
| | - Cody A. Ellingson
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK, Canada
| | - Ryan Dech
- Rink Testify Performance, Winnipeg, MB, Canada
| | | | - J. Patrick Neary
- Faculty of Kinesiology & Health Studies, University of Regina, Regina, SK, Canada
- Corresponding author. Faculty of Kinesiology & Health Studies, 3737 Wascana Pkwy, Regina, SK, S4S 0A2, Canada.
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Labrecque L, Burma JS, Roy MA, Smirl JD, Brassard P. Reproducibility and diurnal variation of the directional sensitivity of the cerebral pressure-flow relationship in men and women. J Appl Physiol (1985) 2021; 132:154-166. [PMID: 34855525 DOI: 10.1152/japplphysiol.00653.2021] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The cerebral pressure-flow relationship has directional sensitivity, meaning the augmentation in cerebral blood flow is attenuated when mean arterial pressure (MAP) increases vs MAP decreases. We employed repeated squat-stands (RSS) to quantify it using a novel metric. However, its within-day reproducibility and the impacts of diurnal variation and biological sex are unknown. Study aims were to evaluate this metric for: 1) within-day reproducibility and diurnal variation in middle (MCA; ∆MCAvT/∆MAPT) and posterior cerebral arteries (PCA; ∆PCAvT/∆MAPT); 2) sex differences. ∆MCAvT/∆MAPT and ∆PCAvT/∆MAPT were calculated at seven time-points (08:00-17:00) in 18 participants (8 women; 24 ± 3 yrs) using the minimum-to-maximum MCAv or PCAv and MAP for each RSS at 0.05 Hz and 0.10 Hz. Relative metric values were also calculated (%MCAvT/%MAPT, %PCAvT/%MAPT). Intraclass correlation coefficient (ICC) evaluated reproducibility, which was good (0.75-0.90) to excellent (>0.90). Time-of-day impacted ∆MCAvT/∆MAPT (0.05 Hz: p = 0.002; 0.10 Hz: p = 0.001), %MCAvT/%MAPT (0.05 Hz: p = 0.035; 0.10 Hz: p = 0.009), and ∆PCAvT/∆MAPT (0.05 Hz: p = 0.024), albeit with small/negligible effect sizes. MAP direction impacted both arteries' metric at 0.10 Hz (all p < 0.024). Sex differences in the MCA only (p = 0.003) vanished when reported in relative terms. These findings demonstrate this metric is reproducible throughout the day in the MCA and PCA and is not impacted by biological sex.
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Affiliation(s)
- Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Marc-Antoine Roy
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
| | - Jonathan David Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research center of the Institut universitaire de cardiologie et de pneumologie de Québec, Québec, Canada
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40
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Burma JS, Kennedy CM, Penner LC, Miutz LN, Galea OA, Ainslie PN, Smirl JD. Long-term heart transplant recipients: heart rate-related effects on augmented transfer function coherence during repeated squat-stand maneuvers in males. Am J Physiol Regul Integr Comp Physiol 2021; 321:R925-R937. [PMID: 34730005 DOI: 10.1152/ajpregu.00177.2021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Previous research has highlighted that squat-stand maneuvers (SSMs) augment coherence values within the cerebral pressure-flow relationship to ∼0.99. However, it is not fully elucidated if mean arterial pressure (MAP) leads to this physiological entrainment independently, or if heart rate (HR) and/or the partial pressure of carbon dioxide (Pco2) also have contributing influences. A 2:1 control-to-case model was used in the present investigation [participant number (n) = 40; n = 16 age-matched (AM); n = 16 donor control (DM); n = 8 heart transplant recipients (HTRs)]. The latter group was used to mechanistically isolate the extent to which HR influences the cerebral pressure-flow relationship. Participants completed 5 min of squat-stand maneuvers at 0.05 Hz (10 s) and 0.10 Hz (5 s). Linear transfer function analysis (TFA) examined the relationship between different physiological inputs (i.e., MAP, HR, and Pco2) and output [cerebral blood velocity (CBV)] during SSM; and cardiac baroreceptor sensitivity (BRS). Compared with DM, cardiac BRS was reduced in AM (P < 0.001), which was further reduced in HTR (P < 0.045). In addition, during the SSM, HR was elevated in HTR compared with both control groups (P < 0.001), but all groups had near-maximal coherence metrics ≥0.98 at 0.05 Hz and ≥0.99 at 0.10 Hz (P ≥ 0.399). In contrast, the mean HR-CBV/Pco2-CBV relationships ranged from 0.38 (HTR) to 0.81 (DM). Despite near abolishment of BRS and blunted HR following heart transplantation, long-term HTR exhibited near-maximal coherence within the MAP-CBV relationship, comparable with AM and DM. Therefore, these results show that the augmented coherence with SSM is driven by blood pressure, whereas elevations in TFA coherence as a result of HR contribution are likely correlational in nature.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Courtney M Kennedy
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Linden C Penner
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Lauren N Miutz
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Olivia A Galea
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada
| | - Philip N Ainslie
- Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, Faculty of Health and Social Development, University of British Columbia, Kelowna, British Columbia, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Calgary, Alberta, Canada.,Centre for Heart, Lung and Vascular Health, School of Health and Exercise Sciences, Faculty of Health and Social Development, University of British Columbia, Kelowna, British Columbia, Canada
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Barnes SC, Haunton VJ, Beishon L, Llwyd O, Robinson TG, Panerai RB. Extremes of cerebral blood flow during hypercapnic squat-stand maneuvers. Physiol Rep 2021; 9:e15021. [PMID: 34617685 PMCID: PMC8495794 DOI: 10.14814/phy2.15021] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2021] [Revised: 08/04/2021] [Accepted: 08/09/2021] [Indexed: 11/24/2022] Open
Abstract
Squat-stand maneuvers (SSMs) are a popular method of inducing blood pressure (BP) oscillations to reliably assess dynamic cerebral autoregulation (dCA), but their effects on the cerebral circulation remain controversial. We designed a protocol whereby participants would perform SSMs under hypercapnic conditions. Alarmingly high values of cerebral blood flow velocity (CBFV) were recorded, leading to early study termination after the recruitment of a single participant. One healthy subject underwent recordings at rest (5 min sitting, 5 min standing) and during two SSMs (fixed and random frequency). Two sets of recordings were collected; one while breathing room air, one while breathing 5% CO2 . Continuous recordings of bilateral CBFV (transcranial Doppler), heart rate (ECG), BP (Finometer), and end-tidal CO2 (capnography) were collected. Peak values of systolic CBFV were significantly higher during hypercapnia (p < 0.01), and maximal values exceeded 200 cm.s-1 . Estimates of dCA (ARI) during hypercapnia were impaired relative to poikilocapnia (p = 0.03). The phase was significantly reduced under hypercapnic conditions (p = 0.03). Here we report extremely high values of CBFV in response to repeated SSMs during induced hypercapnia, in an otherwise healthy subject. Our findings suggest that protocols performing hypercapnic SSMs are potentially dangerous. We, therefore, urge caution if other research groups plan to undertake similar protocols.
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Affiliation(s)
- Samuel C. Barnes
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
| | - Victoria J. Haunton
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
- National Institute for Health Research (NIHR) Leicester Biomedical Research CentreUniversity of LeicesterLeicesterUK
| | - Lucy Beishon
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
| | - Osian Llwyd
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
| | - Thompson G. Robinson
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
- National Institute for Health Research (NIHR) Leicester Biomedical Research CentreUniversity of LeicesterLeicesterUK
| | - Ronney B. Panerai
- Department of Cardiovascular SciencesUniversity of LeicesterLeicesterUK
- National Institute for Health Research (NIHR) Leicester Biomedical Research CentreUniversity of LeicesterLeicesterUK
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Claassen JAHR, Thijssen DHJ, Panerai RB, Faraci FM. Regulation of cerebral blood flow in humans: physiology and clinical implications of autoregulation. Physiol Rev 2021; 101:1487-1559. [PMID: 33769101 PMCID: PMC8576366 DOI: 10.1152/physrev.00022.2020] [Citation(s) in RCA: 295] [Impact Index Per Article: 98.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023] Open
Abstract
Brain function critically depends on a close matching between metabolic demands, appropriate delivery of oxygen and nutrients, and removal of cellular waste. This matching requires continuous regulation of cerebral blood flow (CBF), which can be categorized into four broad topics: 1) autoregulation, which describes the response of the cerebrovasculature to changes in perfusion pressure; 2) vascular reactivity to vasoactive stimuli [including carbon dioxide (CO2)]; 3) neurovascular coupling (NVC), i.e., the CBF response to local changes in neural activity (often standardized cognitive stimuli in humans); and 4) endothelium-dependent responses. This review focuses primarily on autoregulation and its clinical implications. To place autoregulation in a more precise context, and to better understand integrated approaches in the cerebral circulation, we also briefly address reactivity to CO2 and NVC. In addition to our focus on effects of perfusion pressure (or blood pressure), we describe the impact of select stimuli on regulation of CBF (i.e., arterial blood gases, cerebral metabolism, neural mechanisms, and specific vascular cells), the interrelationships between these stimuli, and implications for regulation of CBF at the level of large arteries and the microcirculation. We review clinical implications of autoregulation in aging, hypertension, stroke, mild cognitive impairment, anesthesia, and dementias. Finally, we discuss autoregulation in the context of common daily physiological challenges, including changes in posture (e.g., orthostatic hypotension, syncope) and physical activity.
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Affiliation(s)
- Jurgen A H R Claassen
- Department of Geriatrics, Radboud University Medical Center, Donders Institute for Brain, Cognition, and Behaviour, Nijmegen, The Netherlands
| | - Dick H J Thijssen
- Department of Physiology, Radboud Institute for Health Sciences, Nijmegen, The Netherlands
- Research Institute for Sport and Exercise Sciences, Liverpool John Moores University, Liverpool, United Kingdom
| | - Ronney B Panerai
- Department of Cardiovascular Sciences, University of Leicester, Leicester, United Kingdom
- >National Institute for Health Research Leicester Biomedical Research Centre, University of Leicester, Leicester, United Kingdom
| | - Frank M Faraci
- Departments of Internal Medicine, Neuroscience, and Pharmacology, Carver College of Medicine, University of Iowa, Iowa City, Iowa
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Burma JS, Wassmuth RM, Kennedy CM, Miutz LN, Newel KT, Carere J, Smirl JD. Does task complexity impact the neurovascular coupling response similarly between males and females? Physiol Rep 2021; 9:e15020. [PMID: 34514743 PMCID: PMC8436054 DOI: 10.14814/phy2.15020] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/07/2021] [Accepted: 08/10/2021] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND While previous studies have demonstrated a complex visual scene search elicits a robust neurovascular coupling (NVC) response, it is unknown how the duration of visual stimuli presentation influences NVC metrics. This study examined how stimuli duration, in addition to biological sex and self-reported engagement impact NVC responses. METHODS Participants (n = 20, female = 10) completed four visual paradigms. Three involved simple visual shapes presented at 0.5-, 2-, and 4-s intervals in randomized orders. The fourth paradigm was a complex visual scene search ("Where's Waldo?"). Participants completed eight cycles of 20-s eyes-closed followed by 40-s eyes-open. Transcranial Doppler ultrasound indexed posterior and middle cerebral artery velocities (PCA and MCA). Participants self-reported their engagement following each task (1 [minimal] to 10 [maximal]). RESULTS The "Where's Waldo?" task evoked greater PCA percent increase (all p < 0.001) and area under the curve during the first 30-s of the task (all p < 0.001) compared to simple shapes. Females displayed greater absolute baseline and peak PCA and MCA velocities across all tasks (all p < 0.002). Subjective engagement displayed moderate correlation levels with PCA percent increase (Spearman ρ = 0.58) and area under the curve (Spearman ρ = 0.60) metrics in males, whereas these were weak for females (Spearman ρ = 0.43 and ρ = 0.38, respectively). CONCLUSIONS The complex visual paradigm "Where's Waldo?" greatly augmented the signal-to-noise ratio within the PCA aspects of the NVC response compared to simple shapes. While both sexes had similar NVC responses, task engagement was more related to NVC metrics in males compared to females. Therefore, future NVC investigations should consider task engagement when designing studies.
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Speretta GF, Fornasiero A, Johns JA, Hopkins N, Thijssen DH, Low DA. Effects of Breaking up Deskwork with Physical Activity Combined with Tea Consumption on Cerebrovascular Function, Mood, and Affect. INTERNATIONAL JOURNAL OF CARDIOVASCULAR SCIENCES 2021. [DOI: 10.36660/ijcs.20200209] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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45
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Labrecque L, Smirl JD, Brassard P. Utilization of the repeated squat-stand model for studying the directional sensitivity of the cerebral pressure-flow relationship. J Appl Physiol (1985) 2021; 131:927-936. [PMID: 34264130 DOI: 10.1152/japplphysiol.00269.2021] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Hysteresis in the cerebral pressure-flow relationship describes the superior ability of the cerebrovasculature to buffer cerebral blood flow changes when mean arterial pressure (MAP) increases compared with when MAP decreases. This phenomenon can be evaluated by comparing the change in middle cerebral artery mean blood velocity (MCAv) per change in MAP during either acute increases or decreases in MAP induced by repeated squat-stands (RSS). However, no real baseline can be used for this particular protocol as there is no true stable reference point. Herein, we characterized a novel metric using the greatest MAP oscillations induced by RSS without using an independent baseline value and adjusted for time intervals (ΔMCAvT/ΔMAPT). We also examined whether this metric during each RSS transition was comparable between each other over a 5-min period. ΔMCAvT/ΔMAPT was calculated using the minimum to maximum MCAv and MAP for each RSS performed at 0.05 Hz and 0.10 Hz. We compared averaged ΔMCAvT/ΔMAPT during MAP increases and decreases in 74 healthy participants [9 women; 26 (20-74) yr]. ΔMCAvT/ΔMAPT was lower for MAP increases than MAP decreases at 0.10 Hz RSS only (0.91 ± 0.34 vs. 1.01 ± 0.44 cm·s-1/mmHg; P = 0.0013). For both frequency and MAP direction, time during RSS had no effect on ΔMCAvT/ΔMAPT. This novel analytical method supports the use of the RSS model to evaluate the directional sensitivity of the pressure-flow relationship. These results contribute to the importance of considering the direction of MAP changes, depending on the oscillations frequency when evaluating dynamic cerebral autoregulation.NEW & NOTEWORTHY Repeated squat-stand maneuvers are able to examine the directional sensitivity of the cerebral pressure-flow relationship. These maneuvers induce stable physiological cyclic changes where brain blood flow changes with blood pressure increases are buffered more than blood pressure decreases. These results highlight the importance of considering directional blood pressure changes within cerebral autoregulation.
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Affiliation(s)
- Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec City, Québec, Canada
| | - Jonathan D Smirl
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, British Columbia, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, Alberta, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec City, Québec, Canada
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Migdal KU, Robinson AT, Watso JC, Babcock MC, Lennon SL, Martens CR, Serrador JM, Farquhar WB. Ten days of high dietary sodium does not impair cerebral blood flow regulation in healthy adults. Auton Neurosci 2021; 234:102826. [PMID: 34058717 DOI: 10.1016/j.autneu.2021.102826] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 03/19/2021] [Accepted: 05/14/2021] [Indexed: 10/21/2022]
Abstract
High dietary sodium impairs cerebral blood flow regulation in rodents and is associated with increased stroke risk in humans. However, the effects of multiple days of high dietary sodium on cerebral blood flow regulation in humans is unknown. Therefore, the purpose of this study was to determine whether ten days of high dietary sodium impairs cerebral blood flow regulation. Ten participants (3F/7M; age: 30 ± 10 years; blood pressure (BP): 113 ± 8/62 ± 9 mmHg) participated in this randomized, cross-over design study. Participants were placed on 10-day diets that included either low- (1000 mg/d), medium- (2300 mg/d) or high- (7000 mg/d) sodium separated by ≥four weeks. Urinary sodium excretion, beat-to-beat BP (finger photoplethysmography), middle cerebral artery velocity (transcranial Doppler), and end-tidal carbon dioxide (capnography) was measured. Dynamic cerebral autoregulation during a ten-minute baseline was calculated and cerebrovascular reactivity assessed by determining the percent change in middle cerebral artery blood flow velocity to hypercapnia (8% CO2, 21% oxygen, balance nitrogen) and hypocapnia (via mild hyperventilation). Urinary sodium excretion increased in a stepwise manner (ANOVA P = 0.001) from the low, to medium, to high condition. There were no differences in dynamic cerebral autoregulation between conditions. While there was a trend for a difference during cerebrovascular reactivity to hypercapnia (ANOVA P = 0.06), this trend was abolished when calculating cerebrovascular conductance (ANOVA: P = 0.28). There were no differences in cerebrovascular reactivity (ANOVA P = 0.57) or conductance (ANOVA: P = 0.73) during hypocapnia. These data suggest that ten days of a high sodium diet does not impair cerebral blood flow regulation in healthy adults.
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Affiliation(s)
- Kamila U Migdal
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Austin T Robinson
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America; School of Kinesiology, Auburn University, Auburn, AL, United States of America
| | - Joseph C Watso
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Matthew C Babcock
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Shannon L Lennon
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Christopher R Martens
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America
| | - Jorge M Serrador
- Department of Pharmacology, Physiology & Neuroscience, Rutgers University, Newark, NJ, United States of America
| | - William B Farquhar
- Department of Kinesiology & Applied Physiology, University of Delaware, Newark, DE, United States of America.
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Burma JS, Lapointe AP, Soroush A, Oni IK, Smirl JD, Dunn JF. The validity and reliability of an open source biosensing board to quantify heart rate variability. Heliyon 2021; 7:e07148. [PMID: 34124405 PMCID: PMC8173091 DOI: 10.1016/j.heliyon.2021.e07148] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Revised: 01/17/2021] [Accepted: 05/24/2021] [Indexed: 11/18/2022] Open
Abstract
Background Heart rate variability (HRV) is a popular tool to quantify autonomic function. However, this typically requires an expensive 3-12 lead electrocardiogram (ECG) and BioAmp system. This investigation sought to determine the validity and reliability of an OpenBCI cyton biosensing board (open source) for accurately quantifying HRV. New method A cyton board with a 3-lead ECG was employed to acquire heart rate waveform data, which was processed to obtain HRV within both time- and frequency-domains. The concurrent validity was compared to a simultaneous recording from an industry-standard 3-lead ECG (ADInstruments) (n = 15). The reliability of the cyton board was compared between three days within a 7-day timespan (n = 10). Upright quiet-stance short-term HRV metrics were quantified in time- and frequency-domains. Results The two devices displayed excellent limits of agreements (all log mean differences ±0.4) and very high between-device variable associations (all r 2 > 0.98). Between the three time points in the same subjects, no differences were noted within time- (all p > 0.71) or frequency-domains (all p > 0.88) across testing points. Finally, all HRV metrics exhibited excellent levels of reliability through high Cronbach's Alpha (all ≥0.916) and intraclass correlation coefficients (all ≥0.930); and small standard error of the measurement (all ≤0.7) and typical error of the measurement (all ≤0.1) metrics. Comparison with existing methods The cyton board with 3-lead ECG was compared with an industry-standard ADInstruments ECG during HRV assessments. There were no significant differences between devices with respect to time- and frequency-domains. The cyton board displayed high-levels of between-day reliability and provided values harmonious to previous ECG literature highlighting the applicability for longitudinal studies. Conclusion With proper background knowledge regarding ECG principles and a small degree of set-up complexity, an open source cyton board can be created and employed to perform multimodal HRV assessments at a fraction of the cost (~4%) of an industry-standard ECG setup.
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Affiliation(s)
- Joel S. Burma
- Cerebrovascular Concussion Laboratory, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Andrew P. Lapointe
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ateyeh Soroush
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Ibukunoluwa K. Oni
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
| | - Jonathan D. Smirl
- Cerebrovascular Concussion Laboratory, University of Calgary, Alberta, Canada
- Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada
- Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
| | - Jeff F. Dunn
- Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada
- Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada
- Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada
- Department of Clinical Neurosciences, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Department of Radiology, Cumming School of Medicine, University of Calgary, Calgary, Alberta, Canada
- Corresponding author.
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Burma JS, Miutz LN, Newel KT, Labrecque L, Drapeau A, Brassard P, Copeland P, Macaulay A, Smirl JD. What recording duration is required to provide physiologically valid and reliable dynamic cerebral autoregulation transfer functional analysis estimates? Physiol Meas 2021; 42. [PMID: 33761474 DOI: 10.1088/1361-6579/abf1af] [Citation(s) in RCA: 17] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 03/24/2021] [Indexed: 12/31/2022]
Abstract
Objective. Currently, a recording of 300 s is recommended to obtain accurate dynamic cerebral autoregulation estimates using transfer function analysis (TFA). Therefore, this investigation sought to explore the concurrent validity and the within- and between-day reliability of TFA estimates derived from shorter recording durations from squat-stand maneuvers.Approach. Retrospective analyses were performed on 70 young, recreationally active or endurance-trained participants (17 females; age: 26 ± 5 years, [range: 20-39 years]; body mass index: 24 ± 3 kg m-2). Participants performed 300 s of squat-stands at frequencies of 0.05 and 0.10 Hz, where shorter recordings of 60, 120, 180, and 240 s were extracted. Continuous transcranial Doppler ultrasound recordings were taken within the middle and posterior cerebral arteries. Coherence, phase, gain, and normalized gain metrics were derived. Bland-Altman plots with 95% limits of agreement (LOA), repeated measures ANOVA's, two-tailed paired t-tests, coefficient of variation, Cronbach's alpha, intraclass correlation coefficients, and linear regressions were conducted.Main results. When examining the concurrent validity across different recording durations, group differences were noted within coherence (F(4155) > 11.6,p < 0.001) but not phase (F(4155) < 0.27,p > 0.611), gain (F(4155) < 0.61,p > 0.440), or normalized gain (F(4155) < 0.85,p > 0.359) parameters. The Bland-Altman 95% LOA measuring the concurrent validity, trended to narrow as recording duration increased (60 s: < ±0.4, 120 s: < ±0.3, 180 s < ±0.3, 240 s: < ±0.1). The validity of the 180 and 240 s recordings further increased when physiological covariates were included within regression models.Significance. Future studies examining autoregulation should seek to have participants perform 300 s of squat-stand maneuvers. However, valid and reliable TFA estimates can be drawn from 240 s or 180 s recordings if physiological covariates are controlled.
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Affiliation(s)
- Joel S Burma
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Lauren N Miutz
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada
| | - Kailey T Newel
- Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Audrey Drapeau
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Québec, Canada
| | - Paige Copeland
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Alannah Macaulay
- Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
| | - Jonathan D Smirl
- Cerebrovascular Concussion Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Sport Injury Prevention Research Centre, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, Alberta, Canada.,Hotchkiss Brain Institute, University of Calgary, Calgary, Alberta, Canada.,Integrated Concussion Research Program, University of Calgary, Calgary, AB, Canada.,Alberta Children's Hospital Research Institute, University of Calgary, Calgary, Alberta, Canada.,Libin Cardiovascular Institute of Alberta, University of Calgary, Alberta, Canada.,Concussion Research Laboratory, Faculty of Health and Exercise Science, University of British Columbia, Kelowna, BC, Canada
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49
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Labrecque L, Drapeau A, Rahimaly K, Imhoff S, Brassard P. Dynamic cerebral autoregulation and cerebrovascular carbon dioxide reactivity in middle and posterior cerebral arteries in young endurance-trained women. J Appl Physiol (1985) 2021; 130:1724-1735. [PMID: 33955257 DOI: 10.1152/japplphysiol.00963.2020] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
The integrated responses regulating cerebral blood flow are understudied in women, particularly in relation to potential regional differences. In this study, we compared dynamic cerebral autoregulation (dCA) and cerebrovascular reactivity to carbon dioxide (CVRco2) in the middle (MCA) and posterior cerebral arteries (PCA) in 11 young endurance-trained women (age, 25 ± 4 yr; maximal oxygen uptake, 48.1 ± 4.1 mL·kg-1·min-1). dCA was characterized using a multimodal approach including a sit-to-stand and a transfer function analysis (TFA) of forced blood pressure oscillations (repeated squat-stands executed at 0.05 Hz and 0.10 Hz). The hyperoxic rebreathing test was utilized to characterize CVRco2. Upon standing, the percent reduction in blood velocity per percent reduction in mean arterial pressure during initial orthostatic stress (0-15 s after sit-to-stand), the onset of the regulatory response, and the rate of regulation did not differ between MCA and PCA (all P > 0.05). There was an ANOVA effect of anatomical location for TFA gain (P < 0.001) and a frequency effect for TFA phase (P < 0.001). However, normalized gain was not different between arteries (P = 0.18). Absolute CVRco2 was not different between MCA and PCA (1.55 ± 0.81 vs. 1.30 ± 0.49 cm·s-1/Torr, P = 0.26). Relative CVRco2 was 39% lower in the MCA (2.16 ± 1.02 vs. 3.00 ± 1.09%/Torr, P < 0.01). These findings indicate that the cerebral pressure-flow relationship appears to be similar between the MCA and the PCA in young endurance-trained women. The absence of regional differences in absolute CVRco2 could be women specific, although a direct comparison with a group of men will be necessary to address that issue.NEW & NOTEWORTHY Herein, we describe responses from two major mechanisms regulating cerebral blood flow with a special attention on regional differences in young endurance-trained women. The novel findings are that dynamic cerebral autoregulation and absolute cerebrovascular reactivity to carbon dioxide appear similar between the middle and posterior cerebral arteries of these young women.
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Affiliation(s)
- Lawrence Labrecque
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Québec, Canada
| | - Audrey Drapeau
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Québec, Canada
| | - Kevan Rahimaly
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Québec, Canada
| | - Sarah Imhoff
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Québec, Canada
| | - Patrice Brassard
- Department of Kinesiology, Faculty of Medicine, Université Laval, Quebec City, Québec, Canada.,Research Center of the Institut Universitaire de Cardiologie et de Pneumologie de Québec, Quebec City, Québec, Canada
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50
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Rosenberg AJ, Kay VL, Anderson GK, Luu ML, Barnes HJ, Sprick JD, Rickards CA. The impact of acute central hypovolemia on cerebral hemodynamics: does sex matter? J Appl Physiol (1985) 2021; 130:1786-1797. [PMID: 33914663 DOI: 10.1152/japplphysiol.00499.2020] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Trauma-induced hemorrhage is a leading cause of disability and death due, in part, to impaired perfusion and oxygenation of the brain. It is unknown if cerebrovascular responses to blood loss are differentiated based on sex. We hypothesized that compared to males, females would have reduced tolerance to simulated hemorrhage induced by maximal lower body negative pressure (LBNP), and this would be associated with an earlier reduction in cerebral blood flow and cerebral oxygenation. Healthy young males (n = 29, 26 ± 4 yr) and females (n = 23, 27 ± 5 yr) completed a step-wise LBNP protocol to presyncope. Mean arterial pressure (MAP), stroke volume (SV), middle cerebral artery velocity (MCAv), end-tidal CO2 (etCO2), and cerebral oxygen saturation (ScO2) were measured continuously. Unexpectedly, tolerance to LBNP was similar between the sexes (males, 1,604 ± 68 s vs. females, 1,453 ± 78 s; P = 0.15). Accordingly, decreases (%Δ) in MAP, SV, MCAv, and ScO2 were similar between males and females throughout LBNP and at presyncope (P ≥ 0.20). Interestingly, although decreases in etCO2 were similar between the sexes throughout LBNP (P = 0.16), at presyncope, the %Δ etCO2 from baseline was greater in males compared to females (-30.8 ± 2.6% vs. -21.3 ± 3.0%; P = 0.02). Contrary to our hypothesis, sex does not influence tolerance, or the central or cerebral hemodynamic responses to simulated hemorrhage. However, the etCO2 responses at presyncope do suggest potential sex differences in cerebral vascular sensitivity to CO2 during central hypovolemia.NEW & NOTEWORTHY Tolerance and cerebral blood velocity responses to simulated hemorrhage (elicited by lower body negative pressure) were similar between male and female subjects. Interestingly, the change in etCO2 from baseline was greater in males compared to females at presyncope, suggesting potential sex differences in cerebral vascular sensitivity to CO2 during simulated hemorrhage. These findings may facilitate development of individualized therapeutic interventions to improve survival from hemorrhagic injuries in both men and women.
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Affiliation(s)
- Alexander J Rosenberg
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas.,Integrative Physiology Laboratory, Department of Kinesiology and Nutrition, University of Illinois at Chicago, Illinois
| | - Victoria L Kay
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Garen K Anderson
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - My-Loan Luu
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Haley J Barnes
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
| | - Justin D Sprick
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas.,Division of Renal Medicine, Department of Medicine, Emory University School of Medicine, Atlanta, Georgia
| | - Caroline A Rickards
- Cerebral and Cardiovascular Physiology Laboratory, Department of Physiology and Anatomy, University of North Texas Health Science Center, Fort Worth, Texas
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