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McCormick JJ, Meade RD, King KE, Akerman AP, Notley SR, Kirby NV, Sigal RJ, Kenny GP. Effect of daylong exposure to indoor overheating on autophagy and the cellular stress response in older adults. Appl Physiol Nutr Metab 2024; 49:855-867. [PMID: 38394645 DOI: 10.1139/apnm-2023-0361] [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] [Indexed: 02/25/2024]
Abstract
To protect vulnerable populations during heat waves, public health agencies recommend maintaining indoor air temperature below ∼24-28 °C. While we recently demonstrated that maintaining indoor temperatures ≤26 °C mitigates the development of hyperthermia and cardiovascular strain in older adults, the cellular consequences of prolonged indoor heat stress are poorly understood. We therefore evaluated the cellular stress response in 16 adults (six females) aged 66-78 years during 8 h rest in ambient conditions simulating homes maintained at 22 °C (control) and 26 °C (indoor temperature upper limit proposed by health agencies), as well as non-air-conditioned domiciles during hot weather and heat waves (31 and 36 °C, respectively; all 45% relative humidity). Western blot analysis was used to assess changes in proteins associated with the cellular stress response (autophagy, apoptosis, acute inflammation, and heat shock proteins) in peripheral blood mononuclear cells harvested prior to and following exposure. Following 8 h exposure, no cellular stress response-related proteins differed significantly between the 26 and 22 °C conditions (all, P ≥ 0.056). By contrast, autophagy-related proteins were elevated following exposure to 31 °C (p62: 1.5-fold; P = 0.003) and 36 °C (LC3-II, LC3-II/I, p62; all ≥2.0-fold; P ≤ 0.002) compared to 22 °C. These responses were accompanied by elevations in apoptotic signaling in the 31 and 36 °C conditions (cleaved-caspase-3: 1.8-fold and 3.7-fold, respectively; P ≤ 0.002). Furthermore, HSP90 was significantly reduced in the 36 °C compared to 22 °C condition (0.7-fold; P = 0.014). Our findings show that older adults experience considerable cellular stress during prolonged exposure to elevated ambient temperatures and support recommendations to maintain indoor temperatures ≤26 °C to prevent physiological strain in heat-vulnerable persons.
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Affiliation(s)
- James J McCormick
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Robert D Meade
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
- Harvard T.H. Chan School of Public Health, Harvard University, Boston, MA, USA
| | - Kelli E King
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Ashley P Akerman
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Sean R Notley
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Nathalie V Kirby
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
| | - Ronald J Sigal
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
- Departments of Medicine, Cardiac Sciences and Community Health Sciences, Faculties of Medicine and Kinesiology, University of Calgary, Calgary, AB, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
| | - Glen P Kenny
- Human and Environmental Physiology Research Unit, School of Human Kinetics, University of Ottawa, Ottawa, Canada
- Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, ON, Canada
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Schlagenhauf A, Steuber B, Kneihsl M, Gattringer T, Koestenberger M, Tsiountsioura M, Ziegler T, Tafeit E, Paar M, Wonisch W, Wagner T, Rössler A, Waha JE, Cvirn G, Goswami N. Orthostatic Challenge-Induced Coagulation Activation in Young and Older Persons. Biomedicines 2022; 10:2769. [PMID: 36359289 PMCID: PMC9687232 DOI: 10.3390/biomedicines10112769] [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: 09/27/2022] [Revised: 10/14/2022] [Accepted: 10/29/2022] [Indexed: 08/30/2023] Open
Abstract
The incidence of thrombosis increases with aging. We investigated the coagulatory/haemostatic system across the ages and tested the hypothesis that older persons have a hypercoagulable state compared to younger persons at rest, and that standing up (orthostasis) leads to greater changes in coagulation in older persons. In total, 22 older and 20 young participants performed a 6 min sit-to-stand test (orthostatic challenge). Blood was collected prior to and at the end of standing and haemostatic profiling was performed via thrombelastometry (TEM), calibrated automated thrombogram (CAT) and standard coagulation assays. At baseline, three CAT-derived values indicated enhanced capability to generate thrombin in older participants. However, other measured parameters did not suggest a hypercoagulable state in older participants: prolonged TEM-derived coagulation times (295 vs. 209 s, medians, p = 0.0025) and prothrombin times (103 vs. 114%, medians, p = 0.0087), as well as lower TF levels (440 vs. 672 pg/mL, medians, p = 0.0245) and higher t-PA levels (7.3 vs. 3.8 ng/mL, medians, p = 0.0002), indicative of enhanced fibrinolytic capability, were seen. Younger participants were more sensitive to the orthostatic challenge: CAT-derived endogenous thrombin potentials (ETPs) were only increased in the young (1337 to 1350 nM.min, medians, p = 0.0264) and shortening of PTs was significantly higher in the young vs. older participants (p = 0.0242). Our data suggest that the increased thrombosis propensity in older persons is not primarily attributable to a hyperactive coagulation cascade but may be due to other pathologies associated with aging.
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Affiliation(s)
- Axel Schlagenhauf
- Department of Paediatrics and Adolescent Medicine, Division of General Paediatrics, Medical University of Graz, 8036 Graz, Austria
| | - Bianca Steuber
- Otto Loewi Research Centre, Division of Physiology, Medical University of Graz, 8010 Graz, Austria
| | - Markus Kneihsl
- Department of Neurology, Medical University of Graz, 8036 Graz, Austria
| | - Thomas Gattringer
- Department of Neurology, Medical University of Graz, 8036 Graz, Austria
| | - Martin Koestenberger
- Department of Paediatrics and Adolescent Medicine, Division of General Paediatrics, Medical University of Graz, 8036 Graz, Austria
| | - Melina Tsiountsioura
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Tobias Ziegler
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Erwin Tafeit
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Margret Paar
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Willibald Wonisch
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Thomas Wagner
- Department of Blood Group Serology and Transfusion Medicine, Medical University of Graz, 8036 Graz, Austria
| | - Andreas Rössler
- Otto Loewi Research Centre, Division of Physiology, Medical University of Graz, 8010 Graz, Austria
| | - James Elvis Waha
- General, Visceral and Transplant Surgery, Department of Surgery, Medical University of Graz, 8036 Graz, Austria
| | - Gerhard Cvirn
- Otto Loewi Research Centre, Division of Medicinal Chemistry, Medical University of Graz, 8010 Graz, Austria
| | - Nandu Goswami
- Otto Loewi Research Centre, Division of Physiology, Medical University of Graz, 8010 Graz, Austria
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Bouten J, Bourgois JG, Lootens L, Boone J. Acute apnea and white blood cell count: A biphasic response formal comment on 'Hematologic changes after short term hypoxia in non-elite apnea divers under voluntary dry apnea conditions'. PLoS One 2021; 16:e0253584. [PMID: 34260608 PMCID: PMC8279404 DOI: 10.1371/journal.pone.0253584] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2021] [Accepted: 06/09/2021] [Indexed: 11/18/2022] Open
Affiliation(s)
- Janne Bouten
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
| | - Jan G. Bourgois
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
- Centre of Sports Medicine, Ghent University Hospital, Ghent, Belgium
| | - Leen Lootens
- Doping Control Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
| | - Jan Boone
- Department of Movement and Sports Sciences, Ghent University, Ghent, Belgium
- Doping Control Laboratory, Department of Diagnostic Sciences, Ghent University, Ghent, Belgium
- * E-mail:
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Derakhshan A, Manesh R, Peterson BA, Mohanty BD, Kickler TS, Brotman DJ. Supine-Related Pseudoanemia in Hospitalized Patients. J Hosp Med 2021; 16:219-222. [PMID: 33734980 DOI: 10.12788/jhm.3580] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 11/29/2020] [Indexed: 11/20/2022]
Abstract
A patient's supine posture redistributes plasma into the vascular space, leading to dilution of blood constituents. The extent to which posture may influence identification of hospital-acquired anemia is unknown. Patients in this quasi-experimental study had blood obtained for hemoglobin measurement while recumbent for at least 6 hours, and then again after sitting upright for at least 1 hour. Of the 35 patients who completed the study, 13 were women (37%). Patients had a median increase in hemoglobin of 0.60 g/dL (range, -0.6 to 1.4 g/dL) with sitting, a 5.2% (range, (-4.5% to 15.1%) relative change (P < .001). Ten of 35 patients (29%) exhibited an increase in hemoglobin of 1.0 g/dL or more. Posture influences hemoglobin levels in hospitalized patients on general medicine wards; this knowledge may help curb unnecessary testing to evaluate small changes in hemoglobin concentration.
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Affiliation(s)
- Arsalan Derakhshan
- Department of Internal Medicine, Case Western Reserve University School of Medicine, University Hospital Cleveland Medical Center, Cleveland, Ohio
| | - Reza Manesh
- Department of Internal Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Bennett A Peterson
- Department of Internal Medicine, Saint Joseph's Medical Center, Towson, Maryland
| | - Bibhu D Mohanty
- Division of Cardiology, Department of Medicine, University of South Florida, Morsani College of Medicine, Tampa, Florida
| | - Thomas S Kickler
- Department of Pathology, Johns Hopkins University School of Medicine, Baltimore, Maryland
| | - Daniel J Brotman
- Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, Maryland
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Su MY, Huang YS, Niisato E, Chow K, Juang JMJ, Wu CK, Yu HY, Lin LY, Yang SC, Chang YC. Is a timely assessment of the hematocrit necessary for cardiovascular magnetic resonance-derived extracellular volume measurements? J Cardiovasc Magn Reson 2020; 22:77. [PMID: 33250055 PMCID: PMC7702722 DOI: 10.1186/s12968-020-00689-x] [Citation(s) in RCA: 8] [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: 06/05/2020] [Accepted: 11/17/2020] [Indexed: 01/22/2023] Open
Abstract
BACKGROUND Cardiovascular magnetic resonance (CMR)-derived extracellular volume (ECV) requires a hematocrit (Hct) to correct contrast volume distributions in blood. However, the timely assessment of Hct can be challenging and has limited the routine clinical application of ECV. The goal of the present study was to evaluate whether ECV measurements lead to significant error if a venous Hct was unavailable on the day of CMR. METHODS 109 patients with CMR T1 mapping and two venous Hcts (Hct0: a Hct from the day of CMR, and Hct1: a Hct from a different day) were retrospectively identified. A synthetic Hct (Hctsyn) derived from native blood T1 was also assessed. The study used two different ECV methods, (1) a conventional method in which ECV was estimated from native and postcontrast T1 maps using a region-based method, and (2) an inline method in which ECV was directly measured from inline ECV mapping. ECVs measured with Hct0, Hct1, and Hctsyn were compared for each method, and the reference ECV (ECV0) was defined using the Hct0. The error between synthetic (ECVsyn) and ECV0was analyzed for the two ECV methods. RESULTS ECV measured using Hct1 and Hctsyn were significantly correlated with ECV0 for each method. No significant differences were observed between ECV0 and ECV measured with Hct1 (ECV1; 28.4 ± 6.6% vs. 28.3 ± 6.1%, p = 0.789) and between ECV0 and ECV calculated with Hctsyn (ECVsyn; 28.4 ± 6.6% vs. 28.2 ± 6.2%, p = 0.45) using the conventional method. Similarly, ECV0 was not significantly different from ECV1 (28.5 ± 6.7% vs. 28.5 ± 6.2, p = 0.801) and ECVsyn (28.5 ± 6.7% vs. 28.4 ± 6.0, p = 0.974) using inline method. ECVsyn values revealed relatively large discrepancies in patients with lower Hcts compared with those with higher Hcts. CONCLUSIONS Venous Hcts measured on a different day from that of the CMR examination can still be used to measure ECV. ECVsyn can provide an alternative method to quantify ECV without needing a blood sample, but significant ECV errors occur in patients with severe anemia.
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Affiliation(s)
- Mao-Yuan Su
- Department of Medical Imaging, National Taiwan University Hospital, No.7, Chung-Shan South Road, Taipei, 100 Taiwan
- Department of Medical Imaging and Radiological Technology, Yuanpei University of Medical Technology, Hsinchu, Taiwan
| | - Yu-Sen Huang
- Department of Medical Imaging, National Taiwan University Hospital, No.7, Chung-Shan South Road, Taipei, 100 Taiwan
| | | | - Kelvin Chow
- Siemens Medical Solutions USA Inc., Chicago, IL USA
| | - Jyh-Ming Jimmy Juang
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Cho-Kai Wu
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Hsi-Yu Yu
- Department of Surgery, National Taiwan University Hospital, Taipei, Taiwan
| | - Lian-Yu Lin
- Cardiovascular Center and Division of Cardiology, Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan
| | - Shun-Chung Yang
- Department of Medical Imaging, National Taiwan University Hospital, No.7, Chung-Shan South Road, Taipei, 100 Taiwan
| | - Yeun-Chung Chang
- Department of Medical Imaging, National Taiwan University Hospital, No.7, Chung-Shan South Road, Taipei, 100 Taiwan
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Keller MF, Harrison ML, Lalande S. Impact of Menstrual Blood Loss and Oral Contraceptive Use on Oxygen-carrying Capacity. Med Sci Sports Exerc 2020; 52:1414-1419. [PMID: 31851041 DOI: 10.1249/mss.0000000000002252] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
PURPOSE The effect of menstrual blood loss on oxygen-carrying capacity remains equivocal. The purpose of this study was to determine the effect of menstrual blood loss on hemoglobin mass in young, healthy women. METHODS Twenty-one women (age, 23 ± 6 yr; height, 168 ± 7 cm; weight, 66.1 ± 12.6 kg) with regular menstrual cycles, either using (n = 10) or not using oral contraceptives, participated in the study. Hemoglobin mass was assessed using carbon monoxide rebreathing on three separate occasions over the course of one menstrual cycle. RESULTS Visits for women not using oral contraceptives were performed in the early follicular phase (3 ± 1 d after the onset of menses), late follicular phase (1 ± 1 d after the surge of luteinizing hormone in urine), and luteal phase (9 ± 1 d after the late follicular visit). Visits for women using oral contraceptives were performed in the early follicular phase (3 ± 1 d after the onset of menses), late follicular phase (15 ± 3 d after the onset of menses), and luteal phase (9 ± 2 d after the late follicular visit). Hemoglobin mass was not affected by menstrual cycle phase (early follicular, 618 ± 61; late follicular, 610 ± 65; luteal, 607 ± 68 g; P = 0.52). Interestingly, when normalized to weight, hemoglobin mass was 12% higher in women using oral contraceptives in comparison to nonusers (10.0 ± 1.2 vs 8.9 ± 1.2 g·kg, P < 0.05). CONCLUSION Menstrual blood loss had no measurable effect on hemoglobin mass in eumenorrheic women. However, oral contraceptive use resulted in a greater oxygen-carrying capacity, potentially leading to a greater maximal oxygen uptake.
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Affiliation(s)
- Melissa F Keller
- Department of Kinesiology and Health Education, The University of Texas at Austin, Austin, TX
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Astolfi T, Schumacher YO, Crettaz von Roten F, Saugy M, Faiss R. Does body position before and during blood sampling influence the Athlete Biological Passport variables? Int J Lab Hematol 2019; 42:61-67. [DOI: 10.1111/ijlh.13140] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2019] [Revised: 10/31/2019] [Accepted: 11/20/2019] [Indexed: 11/26/2022]
Affiliation(s)
- Tiffany Astolfi
- REDs, Research and Expertise in antiDoping sciences University of Lausanne Lausanne Switzerland
- ISSUL, Institute of Sport Sciences, University of Lausanne Lausanne Switzerland
| | | | | | - Martial Saugy
- REDs, Research and Expertise in antiDoping sciences University of Lausanne Lausanne Switzerland
- ISSUL, Institute of Sport Sciences, University of Lausanne Lausanne Switzerland
| | - Raphael Faiss
- REDs, Research and Expertise in antiDoping sciences University of Lausanne Lausanne Switzerland
- ISSUL, Institute of Sport Sciences, University of Lausanne Lausanne Switzerland
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Griffin M, Rao VS, Fleming J, Raghavendra P, Turner J, Mahoney D, Wettersten N, Maisel A, Ivey-Miranda JB, Inker L, Tang WHW, Wilson FP, Testani JM. Effect on Survival of Concurrent Hemoconcentration and Increase in Creatinine During Treatment of Acute Decompensated Heart Failure. Am J Cardiol 2019; 124:1707-1711. [PMID: 31601358 DOI: 10.1016/j.amjcard.2019.08.034] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/28/2019] [Revised: 08/21/2019] [Accepted: 08/26/2019] [Indexed: 01/11/2023]
Abstract
Hemoconcentration during the treatment of acute decompensated heart failure is a surrogate for plasma volume reduction and is associated with improved survival, but most definitions only allow for hemoconcentration to be determined retrospectively. An increase in serum creatinine can also be a marker of aggressive decongestion, but in isolation is not specific. Our objective was to determine if combined hemoconcentration and worsening creatinine could better identify patients that were aggressively treated and, as such, may have improved postdischarge outcomes. A total of 4,181 patients hospitalized with acute decompensated heart failure were evaluated. Those who experienced both hemoconcentration and worsening creatinine at any point had a profile consistent with aggressive in-hospital treatment and longer length of stay (p <0.01), higher loop diuretic doses (p <0.001), greater weight (p = 0.001), and net fluid loss (p <0.001) compared with the remainder of the cohort. In isolation, neither worsening creatinine (p = 0.11) nor hemoconcentration (p = 0.36) at any time were associated with improved survival. However, patients who experienced both (21%) had significantly better survival (hazard ratio 0.80, 95% confidence interval 0.69 to 0.94, pinteraction = 0.005). In conclusion, this combination of hemoconcentration and worsening creatinine, which can be determined prospectively during patient care, was associated with in-hospital parameters consistent with aggressive diuresis and improved postdischarge survival.
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Engblom H, Kanski M, Kopic S, Nordlund D, Xanthis CG, Jablonowski R, Heiberg E, Aletras AH, Carlsson M, Arheden H. Importance of standardizing timing of hematocrit measurement when using cardiovascular magnetic resonance to calculate myocardial extracellular volume (ECV) based on pre- and post-contrast T1 mapping. J Cardiovasc Magn Reson 2018; 20:46. [PMID: 29950178 PMCID: PMC6022290 DOI: 10.1186/s12968-018-0464-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2017] [Accepted: 05/24/2018] [Indexed: 12/03/2022] Open
Abstract
BACKGROUND Cardiovascular magnetic resonance (CMR) can be used to calculate myocardial extracellular volume fraction (ECV) by relating the longitudinal relaxation rate in blood and myocardium before and after contrast-injection to hematocrit (Hct) in blood. Hematocrit is known to vary with body posture, which could affect the calculations of ECV. The aim of this study was to test the hypothesis that there is a significant increase in calculated ECV values if the Hct is sampled after the CMR examination in supine position compared to when the patient arrives at the MR department. METHODS Forty-three consecutive patients including various pathologies as well as normal findings were included in the study. Venous blood samples were drawn upon arrival to the MR department and directly after the examination with the patient remaining in supine position. A Modified Look-Locker Inversion recovery (MOLLI) protocol was used to acquire mid-ventricular short-axis images before and after contrast injection from which motion-corrected T1 maps were derived and ECV was calculated. RESULTS Hematocrit decreased from 44.0 ± 3.7% before to 40.6 ± 4.0% after the CMR examination (p < 0.001). This resulted in a change in calculated ECV from 24.7 ± 3.8% before to 26.2 ± 4.2% after the CMR examination (p < 0.001). All patients decreased in Hct after the CMR examination compared to before except for two patients whose Hct remained the same. CONCLUSION Variability in CMR-derived myocardial ECV can be reduced by standardizing the timing of Hct measurement relative to the CMR examination. Thus, a standardized acquisition of blood sample for Hct after the CMR examination, when the patient is still in supine position, would increase the precision of ECV measurements.
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Affiliation(s)
- Henrik Engblom
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Mikael Kanski
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Sascha Kopic
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - David Nordlund
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Christos G. Xanthis
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Robert Jablonowski
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Einar Heiberg
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Anthony H. Aletras
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
- Laboratory of Computing, Medical Informatics and Biomedical – Imaging Technologies, School of Medicine, Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - Marcus Carlsson
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
| | - Håkan Arheden
- Department of Clinical Physiology, Clinical Sciences, Lund University and Lund University Hospital, Getingevägen 3, 221 85 Lund, Sweden
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Folino A, Benzo M, Pasquero P, Laguzzi A, Mesin L, Messere A, Porta M, Roatta S. Vena Cava Responsiveness to Controlled Isovolumetric Respiratory Efforts. JOURNAL OF ULTRASOUND IN MEDICINE : OFFICIAL JOURNAL OF THE AMERICAN INSTITUTE OF ULTRASOUND IN MEDICINE 2017; 36:2113-2123. [PMID: 28543857 DOI: 10.1002/jum.14235] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 01/23/2017] [Indexed: 06/07/2023]
Abstract
OBJECTIVES Respirophasic variation of inferior vena cava (IVC) size is affected by large variability with spontaneous breathing. This study aims at characterizing the dependence of IVC size on controlled changes in intrathoracic pressure. METHODS Ten healthy subjects, in supine position, performed controlled isovolumetric respiratory efforts at functional residual capacity, attaining positive (5, 10, and 15 mmHg) and negative (-5, -10, and -15 mmHg) alveolar pressure levels. The isovolumetric constraint implies that equivalent changes are exhibited by alveolar and intrathoracic pressures during respiratory tasks. RESULTS The IVC cross-sectional area equal to 2.88 ± 0.43 cm2 at baseline (alveolar pressure = 0 mmHg) was progressively decreased by both expiratory and inspiratory efforts of increasing strength, with diaphragmatic efforts producing larger effects than thoracic ones: -55 ± 15% decrease, at +15 mmHg of alveolar pressure (P < .01), -80 ± 33 ± 12% at -15 mmHg diaphragmatic (P < .01), -33 ± 12% at -15 mmHg thoracic. Significant IVC changes in size (P < .01) and pulsatility (P < .05), along with non significant reduction in the response to respiratory efforts, were also observed during the first 30 minutes of supine rest, detecting an increase in vascular filling, and taking place after switching from the standing to the supine position. CONCLUSIONS This study quantified the dependence of the IVC cross-sectional area on controlled intrathoracic pressure changes and evidenced the stronger influence of diaphragmatic over thoracic activity. Individual variability in thoracic/diaphragmatic respiratory pattern should be considered in the interpretation of the respirophasic modulations of IVC size.
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Affiliation(s)
- Anna Folino
- Integrative Physiology Laboratory, Department of Neuroscience, Torino, Italy
| | - Marco Benzo
- Department of Electronics and Telecommunications, Mathematical Biology and Physiology, Politecnico di Torino, Torino, Italy
| | - Paolo Pasquero
- Department of Medical Sciences, AOU San Giovanni Battista, University of Torino, Torino, Italy
| | - Andrea Laguzzi
- Department of Medical Sciences, AOU San Giovanni Battista, University of Torino, Torino, Italy
| | - Luca Mesin
- Department of Electronics and Telecommunications, Mathematical Biology and Physiology, Politecnico di Torino, Torino, Italy
| | - Alessandro Messere
- Integrative Physiology Laboratory, Department of Neuroscience, Torino, Italy
| | - Massimo Porta
- Department of Medical Sciences, AOU San Giovanni Battista, University of Torino, Torino, Italy
| | - Silvestro Roatta
- Integrative Physiology Laboratory, Department of Neuroscience, Torino, Italy
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Chaudhary R, Dubey A, Sonker A. Techniques used for the screening of hemoglobin levels in blood donors: current insights and future directions. J Blood Med 2017; 8:75-88. [PMID: 28740442 PMCID: PMC5503668 DOI: 10.2147/jbm.s103788] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Blood donor hemoglobin (Hb) estimation is an important donation test that is performed prior to blood donation. It serves the dual purpose of protecting the donors' health against anemia and ensuring good quality of blood components, which has an implication on recipients' health. Diverse cutoff criteria have been defined world over depending on population characteristics; however, no testing methodology and sample requirement have been specified for Hb screening. Besides the technique, there are several physiological and methodological factors that affect accuracy and reliability of Hb estimation. These include the anatomical source of blood sample, posture of the donor, timing of sample and several other biological factors. Qualitative copper sulfate gravimetric method has been the archaic time-tested method that is still used in resource-constrained settings. Portable hemoglobinometers are modern quantitative devices that have been further modified to reagent-free cuvettes. Furthermore, noninvasive spectrophotometry was introduced, mitigating pain to blood donor and eliminating risk of infection. Notwithstanding a tremendous evolution in terms of ease of operation, accuracy, mobility, rapidity and cost, a component of inherent variability persists, which may partly be attributed to pre-analytical variables. Hence, blood centers should pay due attention to validation of test methodology, competency of operating staff and regular proficiency testing of the outputs. In this article, we have reviewed various regulatory guidelines, described the variables that affect the measurements and compared the validated technologies for Hb screening of blood donors along with enumeration of their merits and limitations.
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Affiliation(s)
- Rajendra Chaudhary
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences
| | - Anju Dubey
- Department of Transfusion Medicine, T.S. Misra Medical College and Hospital
| | - Atul Sonker
- Department of Transfusion Medicine, Sanjay Gandhi Postgraduate Institute of Medical Sciences, Lucknow, India
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12
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Cvirn G, Kneihsl M, Rossmann C, Paar M, Gattringer T, Schlagenhauf A, Leschnik B, Koestenberger M, Tafeit E, Reibnegger G, Trozic I, Rössler A, Fazekas F, Goswami N. Orthostatic Challenge Shifts the Hemostatic System of Patients Recovered from Stroke toward Hypercoagulability. Front Physiol 2017; 8:12. [PMID: 28223937 PMCID: PMC5293816 DOI: 10.3389/fphys.2017.00012] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2016] [Accepted: 01/06/2017] [Indexed: 01/01/2023] Open
Abstract
Aims: The objective of our study was to assess the effects of orthostatic challenge on the coagulation system in patients with a history of thromboembolic events and to assess how they compared with age-matched healthy controls. Methods: Twenty-two patients with histories of ischemic stroke and 22 healthy age-matched controls performed a sit-to-stand test. Blood was collected prior to- and at the end of- standing in the upright position for 6 min. Hemostatic profiling was performed by determining thrombelastometry and calibrated automated thrombogram values, indices of thrombin generation, standard coagulation times, markers of endothelial activation, plasma levels of coagulation factors and copeptin, and hematocrit. Results: Orthostatic challenge caused a significant endothelial and coagulation activation in patients (Group 1) and healthy controls (Group 2): Plasma levels of prothrombin fragment F1+2 were increased by approximately 35% and thrombin/antithrombin-complex (TAT) increased 5-fold. Several coagulation variables were significantly altered in Group 1 but not in Group 2: Coagulation times (CTs) were significantly shortened and alpha angles, peak rate of thrombin generation (VELINDEX), tissue factor (TF) and copeptin plasma levels were significantly increased (comparison between standing and baseline). Moreover, the shortening of CTs and the rise of copeptin plasma levels were significantly higher in Group 1 vs. Group 2 (comparison between groups). Conclusion: The coagulation system of patients with a history of ischemic stroke can be more easily shifted toward a hypercoagulable state than that of healthy controls. Attentive and long-term anticoagulant treatment is essential to keep patients from recurrence of vascular events.
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Affiliation(s)
- Gerhard Cvirn
- Institute of Physiological Chemistry, Medical University of Graz Graz, Austria
| | - Markus Kneihsl
- Department of Neurology, Medical University of Graz Graz, Austria
| | - Christine Rossmann
- Institute of Physiological Chemistry, Medical University of Graz Graz, Austria
| | - Margret Paar
- Institute of Physiological Chemistry, Medical University of Graz Graz, Austria
| | | | | | - Bettina Leschnik
- Department of Pediatrics, Medical University of Graz Graz, Austria
| | | | - Erwin Tafeit
- Institute of Physiological Chemistry, Medical University of Graz Graz, Austria
| | - Gilbert Reibnegger
- Institute of Physiological Chemistry, Medical University of Graz Graz, Austria
| | - Irhad Trozic
- Gravitational Physiology, Aging and Medicine Research Unit, Institute of Physiology, Medical University of Graz Graz, Austria
| | - Andreas Rössler
- Gravitational Physiology, Aging and Medicine Research Unit, Institute of Physiology, Medical University of Graz Graz, Austria
| | - Franz Fazekas
- Department of Neurology, Medical University of Graz Graz, Austria
| | - Nandu Goswami
- Gravitational Physiology, Aging and Medicine Research Unit, Institute of Physiology, Medical University of Graz Graz, Austria
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13
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Ialongo C, Bernardini S. Phlebotomy, a bridge between laboratory and patient. Biochem Med (Zagreb) 2016; 26:17-33. [PMID: 26981016 PMCID: PMC4783087 DOI: 10.11613/bm.2016.002] [Citation(s) in RCA: 34] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Accepted: 12/06/2015] [Indexed: 12/28/2022] Open
Abstract
The evidence-based paradigm has changed and evolved medical practice. Phlebotomy, which dates back to the age of ancient Greece, has gained experience through the evolution of medicine becoming a fundamental diagnostic tool. Nowadays it connects the patient with the clinical laboratory dimension building up a bridge. However, more often there is a gap between laboratory and phlebotomist that causes misunderstandings and burdens on patient safety. Therefore, the scope of this review is delivering a view of modern phlebotomy to "bridge" patient and laboratory. In this regard the paper describes devices, tools and procedures in the light of the most recent scientific findings, also discussing their impact on both quality of blood testing and patient safety. It also addresses the issues concerning medical aspect of venipuncture, like the practical approach to the superficial veins anatomy, as well as the management of the patient's compliance with the blood draw. Thereby, the clinical, technical and practical issues are treated with the same relevance throughout the entire paper.
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Affiliation(s)
- Cristiano Ialongo
- Laboratory Medicine Department, "Tor Vergata" University Hospital, Rome, Italy
| | - Sergio Bernardini
- Laboratory Medicine Department, "Tor Vergata" University Hospital, Rome, Italy; Experimental Medicine and Surgery Department, "Tor Vergata" University, Rome, Italy
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14
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Baart AM, de Kort WL, van den Hurk K, Pasker-de Jong PC. Hemoglobin assessment: precision and practicability evaluated in the Netherlands-the HAPPEN study. Transfusion 2016; 56:1984-93. [DOI: 10.1111/trf.13546] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2015] [Revised: 01/25/2016] [Accepted: 01/25/2016] [Indexed: 11/28/2022]
Affiliation(s)
- A. Mireille Baart
- Department of Donor Studies; Sanquin Research; Amsterdam the Netherlands
| | - Wim L.A.M. de Kort
- Department of Donor Studies; Sanquin Research; Amsterdam the Netherlands
| | - Katja van den Hurk
- Department of Donor Studies; Sanquin Research; Amsterdam the Netherlands
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15
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Complete blood count at the ED: preanalytic variables for hemoglobin and leukocytes. Am J Emerg Med 2015; 33:1152-7. [PMID: 26050560 DOI: 10.1016/j.ajem.2015.05.011] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2014] [Revised: 04/27/2015] [Accepted: 05/13/2015] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE The objective of this study is to determine the ways in which preanalytic factors related to physiologic status can affect the complete blood cell count (CBC) in patients referring to an emergency department (ED). METHODS Over a 1-year period, the results of hemoglobin (Hb) level and white blood cell (WBC) counts of the first CBC tests undertaken in consecutive patients (n = 11487) referring to the ED were compared with those obtained in the same patients at a second test undertaken within 24 hours of admission. A prospective evaluation of the same differences was made in another group (group 2) of 1025 consecutive ED patients, several clinical characteristics being taken into consideration. RESULTS Mean Hb concentrations were higher in the first (range, 8.0-15.9 g/dL) than in the second test results (median overestimation, 0.4-0.8 g/dL; P < .0001). At multivariate analysis of results in group 2 patients, fluid administration (>0.5 L) and the presence of edema played a significant role in the initial overestimation of Hb level (P = .001 and P = .045, respectively). The comparison between leukocyte counts (WBC) showed that values from the first were higher than those in the second test (median overestimation ranging from 0.42 to 3.63 × 10(9)/L cells, in the range counts from 4.0 to 30.0 × 10(9)/L). None of the clinical factors studied appeared to have affected this overestimation. CONCLUSIONS On interpreting CBC results in patients admitted to the ED, physicians must consider the effect of physiologic variables on Hb level (mainly hydration status) and WBC count (mental and physical stress).
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Abstract
The hematology analyzers of today provide more reproducible analyses compared with those of a few decades ago, necessitating an evolution in hematology quality practices. The improved performance allows use of simple quality control rules. This improved performance also renders the repeat analysis of critical value specimens non value added. Some of the patient averaging techniques have become outmoded and need to be replaced by less complicated calculations but with truncation of predictable outlying populations. The ready availability of comparative peer quality control values helps to improve analyzer precision and accuracy, and simplifies instrument validation and calibration.
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Affiliation(s)
- George S Cembrowski
- Laboratory Medicine and Pathology, 4B1.24 Mackenzie Health Sciences Centre, University of Alberta Hospital, 8440-112 Street, Edmonton, AB T6G 2B7, Canada.
| | - Gwen Clarke
- Canadian Blood Services, Medical Office 8249 -114th Street, Edmonton, AB T6G 2R8, Canada
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17
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Gómez Perales JL. Blood volume analysis by radioisotopic dilution techniques: state of the art. Appl Radiat Isot 2014; 96:71-82. [PMID: 25479437 DOI: 10.1016/j.apradiso.2014.11.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2014] [Revised: 09/19/2014] [Accepted: 11/14/2014] [Indexed: 12/17/2022]
Abstract
In the last years, there has been a growing recognition of the importance of blood volume abnormalities in the pathophysiology of several conditions and, consequently, a growing interest of accurate and rapid volume status assessment. Accordingly, there has been a surge of interest in blood volume analysis by radioisotopic dilution technique. However, there are still some controversies about this technique, such as the use of the f-cell ratio, the errors associated with the method and the reference values. This review aims to revise and discuss the theoretical and methodological aspects of this technique and also to discuss their controversies. Furthermore, it is questioned whether red cell volume or plasma volume can be accurately estimated once the other quantity has been measured or should red cell volume and plasma volume be directly measured. As a conclusion, blood volume analysis by radioisotopic dilution technique is still valid and very useful.
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Affiliation(s)
- Jesús Luis Gómez Perales
- Nuclear Medicine Service, Puerta del Mar University Hospital, Avenida Ana de Viya 21, 11009 Cádiz, Spain.
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18
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Affiliation(s)
- Richard T Silver
- Division of Hematology/Medical Oncology, Weill Cornell Medical College , New York, NY , USA
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19
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De Vis JB, Hendrikse J, Groenendaal F, de Vries LS, Kersbergen KJ, Benders MJNL, Petersen ET. Impact of neonate haematocrit variability on the longitudinal relaxation time of blood: Implications for arterial spin labelling MRI. NEUROIMAGE-CLINICAL 2014; 4:517-25. [PMID: 24818078 PMCID: PMC3984444 DOI: 10.1016/j.nicl.2014.03.006] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/21/2013] [Revised: 03/13/2014] [Accepted: 03/14/2014] [Indexed: 11/28/2022]
Abstract
BACKGROUND AND PURPOSE The longitudinal relaxation time of blood (T 1b) is influenced by haematocrit (Hct) which is known to vary in neonates. The purpose of this study was threefold: to obtain T 1b values in neonates, to investigate how the T 1b influences quantitative arterial spin labelling (ASL), and to evaluate if known relationships between T 1b and haematocrit (Hct) hold true when Hct is measured by means of a point-of-care device. MATERIALS AND METHODS One hundred and four neonates with 120 MR scan sessions (3 T) were included. The T 1b was obtained from a T 1 inversion recovery sequence. T 1b-induced changes in ASL cerebral blood flow estimates were evaluated. The Hct was obtained by means of a point-of-care device. Linear regression analysis was used to investigate the relation between Hct and MRI-derived R1 of blood (the inverse of the T 1b). RESULTS Mean T 1b was 1.85 s (sd 0.2 s). The mean T 1b in preterm neonates was 1.77 s, 1.89 s in preterm neonates scanned at term-equivalent age (TEA) and 1.81 s in diseased neonates. The T 1b in the TEA was significantly different from the T 1b in the preterm (p < 0.05). The change in perfusion induced by the T 1b was -11% (sd 9.1%, p < 0.001). The relation between arterial-drawn Hct and R1b was R1b = 0.80 × Hct + 0.22, which falls within the confidence interval of the previously established relationships, whereas capillary-drawn Hct did not correlate with R1b. CONCLUSION We demonstrated a wide variability of the T 1b in neonates and the implications it could have in methods relying on the actual T 1b as for instance ASL. It was concluded that arterial-drawn Hct values obtained from a point-of-care device can be used to infer the T 1b whereas our data did not support the use of capillary-drawn Hct for T 1b correction.
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Key Words
- ASL, arterial spin labelling
- Arterial spin labelling
- Blood T1
- CBF, cerebral blood flow
- CBF1.6, cerebral blood flow quantified with a T1b of 1.6 s
- CBF1.85, cerebral blood flow quantified with a T1b of 1.85 s
- CBFcor, cerebral blood flow quantified with the corrected T1b
- CBFmean, cerebral blood flow quantified with the mean T1b found in our study
- Cerebral blood flow
- Haematocrit
- Hct, haematocrit
- Hctad, haematocrit measured on an arterial-drawn blood sample
- Hctcd, haematocrit measured on a capillary-drawn blood sample
- MRI
- MRI, magnetic resonance imaging
- NPD, normalized perfusion difference
- Neonates
- PCA, postconceptional age
- PNA, postnatal age
- POCT, point-of-care test
- R1b, longitudinal relaxation rate constant of blood
- T1b, longitudinal relaxation time of blood
- TEA, term-equivalent age
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Affiliation(s)
- J B De Vis
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - J Hendrikse
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - F Groenendaal
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - L S de Vries
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - K J Kersbergen
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - M J N L Benders
- Department of Neonatology, University Medical Center Utrecht, Utrecht, The Netherlands
| | - E T Petersen
- Department of Radiology, University Medical Center Utrecht, Utrecht, The Netherlands ; Department of Radiotherapy, University Medical Center Utrecht, Utrecht, The Netherlands
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20
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Tavares MM, Diquattro PJ, Sweeney JD. Reduction in red blood cell transfusion associated with engagement of the ordering physician. Transfusion 2014; 54:2625-30. [PMID: 24472040 DOI: 10.1111/trf.12552] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 11/24/2013] [Accepted: 12/04/2013] [Indexed: 01/13/2023]
Abstract
BACKGROUND Data on red blood cell (RBC) transfusion in the United States show variation in practice and overprescribing or overdosing is considered to be prevalent. Education or restrictive interventions could modify practice. STUDY DESIGN AND METHODS RBC transfusion and mortality rates were recorded in a single institution over a 15-year period. The first 3 years were used as a baseline. Education measures were used to influence practice for 3 years followed by a 9-year period when questionable RBC orders in nonbleeding inpatients resulted in prospective physician notification for potential modification. Physician notification was done by blood bank technologists with transfusion medicine physician support, if needed. Pretransfusion hemoglobin levels of more than 9 g/dL were recommended for cancellation and levels between 8 and 9 g/dL advised for a single unit, if 2 or more units were requested. RBC transfusion rates were described as inpatient units per 1000 discharges to allow for interyear comparison. RESULTS A downward trend in RBC transfusion was noted for the intervention period. Comparison of the baseline period with the past 3 years of the intervention period showed an approximate 33% decrease, which was highly significant (508 ± 66 vs. 341 ± 32, p < 0.01). Inpatient mortality rates declined over this period. CONCLUSION Physician education in appropriate transfusion practice is desirable but may not greatly impact RBC use. Engagement of physicians who prescribe RBCs that appear inappropriate for indication or dose was associated with a significant decline in RBC use without evidence of a change in mortality.
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Affiliation(s)
- Maria M Tavares
- Blood Bank, Roger Williams Hospital, Providence, Rhode Island
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21
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Comparison between two portable hemoglobinometers and a reference method to verify the reliability of screening in blood donors. Transfus Apher Sci 2013; 49:578-82. [DOI: 10.1016/j.transci.2013.09.004] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2013] [Revised: 08/30/2013] [Accepted: 09/13/2013] [Indexed: 11/23/2022]
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22
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Low iron storage and mild anemia in postural tachycardia syndrome in adolescents. Clin Auton Res 2013; 23:175-9. [PMID: 23720007 DOI: 10.1007/s10286-013-0198-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2012] [Accepted: 05/08/2013] [Indexed: 01/01/2023]
Abstract
OBJECTIVE We reported low iron storage in neurally mediated syncope (NMS). While reduced red cell mass indicative of anemia has been reported in POTS, iron indices and hemoglobin (Hb) data were not reported. We investigated whether POTS, like NMS, is associated with low iron storage and anemia. METHODS Thirty two children evaluated in 2007 and 2008 for probable POTS by a standing or tilt test or both at Texas Children's Hospital were included in a retrospective study. We measured serum ferritin (SF) and Hb values. We defined iron deficiency as SF < 12 μg/L, low iron storage as SF ≤ 25 μg/L, anemia as low Hb values for age and sex, and POTS as ≥2 symptoms of orthostatic intolerance >3 months and increased HR of >30 BPM or HR of >120 BPM within 10 min of standing or 70° tilt. RESULTS Twenty four children had POTS, ages 12-18 years, 17 (71 %) were females. Value range (median) of SF 2-289 μg/L (25), Hb 11.5-14.6 (12.5) in females and 12-15.9 g/L (13.6) in males. Patients with POTS, when compared with normal US pediatric population had higher prevalence of low iron storage (50 vs. 14 %), iron deficiency (25 % of teenage girls vs. 9 %, and 16 % of teenage boys vs. 1 %), and anemia (18 % of teenage girls vs. 1.5 %, and 43 % of teenage boys vs. 0.1 %). INTERPRETATION Low iron storage and mild anemia are associated with POTS suggesting that low iron storage is a potentially pathophysiologic factor in both POTS and NMS.
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24
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Cvirn G, Schlagenhauf A, Leschnik B, Koestenberger M, Roessler A, Jantscher A, Vrecko K, Juergens G, Hinghofer-Szalkay H, Goswami N. Coagulation changes during presyncope and recovery. PLoS One 2012; 7:e42221. [PMID: 22876309 PMCID: PMC3410921 DOI: 10.1371/journal.pone.0042221] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2012] [Accepted: 07/02/2012] [Indexed: 02/02/2023] Open
Abstract
Orthostatic stress activates the coagulation system. The extent of coagulation activation with full orthostatic load leading to presyncope is unknown. We examined in 7 healthy males whether presyncope, using a combination of head up tilt (HUT) and lower body negative pressure (LBNP), leads to coagulation changes as well as in the return to baseline during recovery. Coagulation responses (whole blood thrombelastometry, whole blood platelet aggregation, endogenous thrombin potential, markers of endothelial activation and thrombin generation), blood cell counts and plasma mass density (for volume changes) were measured before, during, and 20 min after the orthostatic stress. Maximum orthostatic load led to a 25% plasma volume loss. Blood cell counts, prothrombin levels, thrombin peak, endogenous thrombin potential, and tissue factor pathway inhibitor levels increased during the protocol, commensurable with hemoconcentration. The markers of endothelial activation (tissue factor, tissue plasminogen activator), and thrombin generation (F1+2, prothrombin fragments 1 and 2, and TAT, thrombin-antithrombin complex) increased to an extent far beyond the hemoconcentration effect. During recovery, the markers of endothelial activation returned to initial supine values, but F1+2 and TAT remained elevated, suggestive of increased coagulability. Our findings of increased coagulability at 20 min of recovery from presyncope may have greater clinical significance than short-term procoagulant changes observed during standing. While our experiments were conducted in healthy subjects, the observed hypercoagulability during graded orthostatic challenge, at presyncope and in recovery may be an important risk factor particularly for patients already at high risk for thromboembolic events (e.g. those with coronary heart disease, atherosclerosis or hypertensives).
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Affiliation(s)
- Gerhard Cvirn
- Institute of Physiological Chemistry, Medical University of Graz, Graz, Austria
| | - Axel Schlagenhauf
- Department of Paediatrics, Medical University of Graz, Graz, Austria
| | - Bettina Leschnik
- Department of Paediatrics, Medical University of Graz, Graz, Austria
| | | | - Andreas Roessler
- Institute of Physiology, Medical University of Graz, Graz, Austria
| | | | - Karoline Vrecko
- Institute of Physiological Chemistry, Medical University of Graz, Graz, Austria
| | - Guenther Juergens
- Institute of Physiological Chemistry, Medical University of Graz, Graz, Austria
| | | | - Nandu Goswami
- Institute of Physiology, Medical University of Graz, Graz, Austria
- * E-mail:
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Lalande S, Kelsey JW, Joyner MJ, Johnson BD. Determination of blood volume by pulse CO-oximetry. Physiol Meas 2011; 33:19-27. [PMID: 22156221 DOI: 10.1088/0967-3334/33/1/19] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The objective of this study was to determine whether changes in carboxyhaemoglobin (COHb) saturation following carbon monoxide (CO) rebreathing can be accurately detected by pulse CO-oximetry in order to determine blood volume. Noninvasive measurements of carboxyhaemoglobin saturation (SpCO) were continuously monitored by pulse CO-oximetry before, during and following 2 min of CO rebreathing. Reproducibility and accuracy of noninvasive blood volume measurements were determined in 16 healthy non-smoking individuals (15 males, age: 28 ± 2 years, body mass index: 25.4 ± 0.6 kg m(-2)) through comparison with blood volume measurements calculated from invasive measurements of COHb saturation. The coefficient of variation for noninvasive blood volume measurements performed on separate days was 15.1% which decreases to 9.1% when measurements were performed on the same day. Changes in COHb saturation and SpCO following CO rebreathing were strongly correlated (r = 0.90, p < 0.01), resulting in a significant correlation between invasive and noninvasive blood volume measurements (r = 0.83, p = 0.02). Changes in SpCO following CO rebreathing can be accurately detected by pulse CO-oximetry, which could potentially provide a simplified, convenient and reproducible method to rapidly determine blood volume in healthy individuals.
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Affiliation(s)
- S Lalande
- Division of Cardiovascular Diseases, Department of Medicine, Mayo Clinic, Rochester, MN 55905, USA.
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26
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Cable RG, Steele WR, Melmed RS, Johnson B, Mast AE, Carey PM, Kiss JE, Kleinman SH, Wright DJ. The difference between fingerstick and venous hemoglobin and hematocrit varies by sex and iron stores. Transfusion 2011; 52:1031-40. [PMID: 22014071 DOI: 10.1111/j.1537-2995.2011.03389.x] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Fingerstick blood samples are used to estimate donor venous hemoglobin (Hb). STUDY DESIGN AND METHODS Fingerstick Hb or hematocrit (Hct) was determined routinely for 2425 selected donors at six blood centers, along with venous Hb. Using sex and measures of iron status including absent iron stores (AIS; ferritin < 12 ng/mL), linear regression models were developed to predict venous Hb from fingerstick. RESULTS Across all subjects, fingerstick Hb was higher than venous Hb in the higher part of the clinical range, but lower in the lower part of the range. The relationship varied by sex and iron status. Across centers, a female donor had on average a venous Hb result 0.5 to 0.8 g/dL lower than a male donor with the same fingerstick Hb and iron status. Similarly, a donor with AIS had on average a venous Hb result 0.3 to 1.1 g/dL lower than an iron-replete donor with the same fingerstick value and sex. An iron-replete male donor with a fingerstick result at the cutoff (Hb 12.5 g/dL) had an acceptable expected venous Hb (12.8 to 13.8 g/dL). A female donor with AIS with a fingerstick result at the cutoff had an expected venous Hb below 12.5 g/dL (11.7 to 12.4 g/dL). Of females with AIS, 40.2% donated blood when their venous Hb was less than 12.5 g/dL. CONCLUSIONS Fingerstick is considered a useful estimator of venous Hb. However, in some donor groups, particularly female donors with AIS, fingerstick overestimates venous Hb at the donation cutoff. This significant limitation should be considered in setting donor fingerstick Hb or Hct requirements.
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Affiliation(s)
- Ritchard G Cable
- New England Region, American Red Cross Blood Services, 209 Farmington Avenue, Farmington, CT 06032, USA.
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Papa F, Rongioletti M, Ventura MD, Di Turi F, Cortesi M, Pasqualetti P, Majolini MB, Collegiani V, Cicchese M, Notarmuzi ML, Agostino R, Liumbruno GM. Blood cell counting in neonates: a comparison between a low volume micromethod and the standard laboratory method. BLOOD TRANSFUSION = TRASFUSIONE DEL SANGUE 2011; 9:400-6. [PMID: 21839016 PMCID: PMC3200409 DOI: 10.2450/2011.0082-10] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Subscribe] [Scholar Register] [Received: 09/15/2010] [Accepted: 11/25/2010] [Indexed: 11/21/2022]
Abstract
BACKGROUND Iatrogenic anaemia caused by repeated blood sampling to monitor laboratory parameters can contribute, particularly in neonates, to the need for transfusion. "Point of care" laboratory equipment uses smaller amounts of blood for analytic determinations and could, therefore, help to prevent secondary anaemia. In this study we compared the results of haematological parameters measured using a standard laboratory method and using a "point of care" micromethod, with the aim of validating the use of this latter method in clinical practice in neonatology. MATERIALS AND METHODS One hundred and fifty venous or capillary blood samples were taken from full-term or premature neonates 2-4 hours or 48 hours after birth. Each sample was processed by a standard haematology analyser and another micromethod instrument. Bland-Altman plots were constructed for each parameter and intra-class coefficients of correlation were calculated in order to evaluate the concordance between the two analysers. RESULTS The concordance between the data obtained with the two analysers, expressed as the intra-class correlation, was 0.98 for white blood cell count, 0.97 for haemoglobin concentration, 0.96 for haematocrit, 0.95 for mean red cell volume and 0.98 for platelet count. The micromethod produced overestimated mean values for the leucocyte count (+1.27; p<0.001), haematocrit (+1.80; p<0.001) and platelet count (+13.55; p<0.001). CONCLUSIONS Overall, the concordance between the values obtained with the two analysers was high for each of the parameters taken into consideration. In the case of haemoglobin and leucocytes, give the high intra-class correlation and lack of systematic overestimation of one method over another, the micromethod guarantees a correct evaluation; however, despite the high intra-class correlations for platelet counts, the systemic error seems to suggest that the micromethod cannot guarantee an appropriate evaluation of this parameter.
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Affiliation(s)
- Fabrizio Papa
- Clinical Pathology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Mauro Rongioletti
- Clinical Pathology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Marco Della Ventura
- Immunohaematology and Transfusion Medicine Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Francesco Di Turi
- Neonatology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Maurizio Cortesi
- Clinical Pathology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | | | | | - Valeria Collegiani
- Clinical Pathology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Marika Cicchese
- Neonatology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | | | - Rocco Agostino
- Neonatology Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
| | - Giancarlo Maria Liumbruno
- Immunohaematology and Transfusion Medicine Unit, “San Giovanni Calibita” Fatebenefratelli Hospital, Rome
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Validation of a novel traditional chinese medicine pulse diagnostic model using an artificial neural network. EVIDENCE-BASED COMPLEMENTARY AND ALTERNATIVE MEDICINE 2011; 2012:685094. [PMID: 21918652 PMCID: PMC3171770 DOI: 10.1155/2012/685094] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Revised: 06/27/2011] [Accepted: 07/12/2011] [Indexed: 11/30/2022]
Abstract
In view of lacking a quantifiable traditional Chinese medicine (TCM) pulse
diagnostic model, a novel TCM pulse diagnostic model was introduced to quantify
the pulse diagnosis. Content validation was performed with a panel of TCM
doctors. Criterion validation was tested with essential hypertension. The gold
standard was brachial blood pressure measured by a sphygmomanometer. Two hundred
and sixty subjects were recruited (139 in the normotensive group and 121 in the
hypertensive group). A TCM doctor palpated pulses at left and right cun, guan,
and chi points, and quantified pulse qualities according to eight elements
(depth, rate, regularity, width, length, smoothness, stiffness, and strength) on
a visual analog scale. An artificial neural network was used to develop a pulse
diagnostic model differentiating essential hypertension from normotension.
Accuracy, specificity, and sensitivity were compared among various diagnostic
models. About 80% accuracy was attained among all models. Their specificity and
sensitivity varied, ranging from 70% to nearly 90%. It suggested that the novel
TCM pulse diagnostic model was valid in terms of its content and diagnostic
ability.
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Tong E, Murphy WG, Kinsella A, Darragh E, Woods J, Murphy C, McSweeney E. Capillary and venous haemoglobin levels in blood donors: a 42-month study of 36 258 paired samples. Vox Sang 2010; 98:547-53. [DOI: 10.1111/j.1423-0410.2009.01285.x] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Bai SJ, Lee JW, Lee KY. Fluid therapy: classification and characteristics of intravenous fluids. JOURNAL OF THE KOREAN MEDICAL ASSOCIATION 2010. [DOI: 10.5124/jkma.2010.53.12.1103] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Affiliation(s)
- Sun Joon Bai
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Jong Wha Lee
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
| | - Ki-Young Lee
- Department of Anesthesiology and Pain Medicine, Yonsei University College of Medicine, Seoul, Korea
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Moralidis E, Papanastassiou E, Arsos G, Chilidis I, Gerasimou G, Gotzamani-Psarrakou A. A single measurement with51Cr-tagged red cells or125I-labeled human serum albumin in the prediction of fractional and whole blood volumes: an assessment of the limitations. Physiol Meas 2009; 30:559-71. [DOI: 10.1088/0967-3334/30/7/003] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Akizawa T, Pisoni RL, Akiba T, Saito A, Fukuhara S, Asano Y, Hasegawa T, Port FK, Kurokawa K. Japanese haemodialysis anaemia management practices and outcomes (1999-2006): results from the DOPPS. Nephrol Dial Transplant 2008; 23:3643-53. [PMID: 18577535 PMCID: PMC2568010 DOI: 10.1093/ndt/gfn346] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2007] [Accepted: 05/26/2008] [Indexed: 11/16/2022] Open
Abstract
BACKGROUND Japanese haemodialysis (HD) patients not only have a very low mortality and hospitalization risk but also low haemoglobin (Hb) levels. Internationally, anaemia is associated with mortality, hospitalization and health-related quality of life (QoL) measures of HD patients. METHODS Longitudinal data collected from 1999 to 2006 from 60 to 64 representative Japanese dialysis units participating in the Dialysis Outcomes and Practice Patterns Study (DOPPS) were used to describe anaemia management practices and outcomes for Japanese HD patients. RESULTS From 1999 to 2006, patient mean Hb increased from 9.7 g/dl to 10.4 g/dl, and the percentage of facilities with median Hb >or=10 g/dl increased from 27% to 75%. Hb was measured in the supine position for 90% of patients, resulting in substantially lower reported Hb values than those seen in other countries. As of 2006, erythropoietin (Epo) was prescribed to 83% of HD patients; mean Epo dose was 5231 units/week; intravenous (IV) iron use was 33% and median IV iron dose was 160 mg/month. Many patient- and facility-level factors were significantly related to higher Hb. A consistent overall pattern of lower mortality risk with higher baseline Hb levels was seen (RR = 0.89 per 1 g/dl higher Hb, P = 0.003). Facilities with median Hb >or=10.4 displayed a lower mortality risk (RR = 0.77, P = 0.03) versus facility median Hb <10.4 g/dl. Lower Hb levels were not significantly related to hospitalization risk, but were associated with lower QoL scores. CONCLUSIONS These results provide detailed information on anaemia management practices in Japan and the relationships of anaemia control with outcomes, with implications of anaemia management worldwide.
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Affiliation(s)
- Tadao Akizawa
- Division of Nephrology, Showa University School of Medicine, Shinagawa, Tokyo 142-8666, Japan.
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Raj SR. Is cardiac output the key to vasovagal syncope? A reevaluation of putative pathophysiology. Heart Rhythm 2008; 5:1702-3. [PMID: 18996054 DOI: 10.1016/j.hrthm.2008.09.022] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Indexed: 11/15/2022]
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Masoud M, Sarig G, Brenner B, Jacob G. Orthostatic hypercoagulability: a novel physiological mechanism to activate the coagulation system. Hypertension 2008; 51:1545-51. [PMID: 18413485 DOI: 10.1161/hypertensionaha.108.112003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Orthostatic stress causes significant plasma shift and raises transmural pressure in lower extremities, resulting in an increase in endothelial activation and plasma proteins concentrations, possibly including coagulation factors. This may lead to activation of the coagulation system during standing. To test this hypothesis, we recruited 18 healthy volunteers (9 females and 9 males; mean age: 25+/-1.2 years; body mass index: 21.7+/-0.5 kg/m(2)). Hemodynamics, plasma shift (extrapolated from sequential hematocrit concentration), plasma proteins, and coagulation tests, including procoagulants; fibrinogen, factor V, and factor VIII activity; prothrombin fragments 1 and 2; and endothelial activation-related factors (tissue factor and von Willebrand factor), as well as protein C global pathway, were determined at rest supine and at 15 minutes, 30 minutes, and 60 minutes of still standing. Thirty minutes of standing caused a decrease in plasma volume by 12.0+/-0.5% and an increase in plasma protein by 13.0+/-0.7%. Fibrinogen, factor V, and factor VIII activity rose by 12.0+/-1.2%, 13.0+/-1.0%, and 40.0+/-6.0% (P<0.002 for all), respectively. Prothrombin fragments 1 and 2 were elevated by 150.0+/-30.0%. Tissue factor and von Willebrand factor increased by 30.0+/-9.0% and 17.4+/-51.0% (P<0.02 for both), respectively. However, protein C assay results decreased from 0.95+/-0.20 to 0.83+/-0.16 (P<0.001). We hereby introduce a novel physiological mechanism, "orthostatic procoagulation," that should be considered during coagulation tests. Furthermore, it could be extrapolated to the pathophysiology of stasis and venous thromboembolism.
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Affiliation(s)
- Muhannad Masoud
- J. Recanati Autonomic Dysfunction Center and the Thrombosis and Hemostasis Unit, Medicine, Rambam Health Care Campus, and Bruce Rappaport Faculty of Medicine, Technion-IIT, Haifa, Israel
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Robertson D. The pathophysiology and diagnosis of orthostatic hypotension. Clin Auton Res 2008; 18 Suppl 1:2-7. [PMID: 18368300 DOI: 10.1007/s10286-007-1004-0] [Citation(s) in RCA: 122] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2007] [Accepted: 06/30/2007] [Indexed: 11/28/2022]
Abstract
Orthostatic Hypotension (OH) is a common manifestation of blood pressure dysregulation. OH takes a heavy toll on quality of life. It has many potential etiologies, and many effects of aging can increase susceptibility to OH. Neurological disorders are especially likely to cause severe OH. In this brief review, the pathogenesis of OH is considered, particularly in terms of autonomic neuropathy, multiple system atrophy (MSA), pure autonomic failure, baroreflex failure, and dopamine beta hydroxylase deficiency. While OH is difficult to treat, its control greatly enhances the quality of life.
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Affiliation(s)
- David Robertson
- Autonomic Dysfunction Center, Depts. of Medicine and Pharmacology, Vanderbilt University, AA 3228 Medical Center North, 1161 21st Avenue South, Nashville, TN 37323-2195, USA.
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Thrall G, Lane D, Carroll D, Lip GY. A Systematic Review of the Prothrombotic Effects of an Acute Change in Posture. Chest 2007; 132:1337-47. [DOI: 10.1378/chest.06-2978] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022] Open
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Affiliation(s)
- Andrew C Ertl
- Autonomic Dysfunction Center, Departments of Medicine, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-2195, USA
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Papaioannou TG, Karatzis EN, Vavuranakis M, Lekakis JP, Stefanadis C. Assessment of vascular wall shear stress and implications for atherosclerotic disease. Int J Cardiol 2006; 113:12-8. [PMID: 16889847 DOI: 10.1016/j.ijcard.2006.03.035] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/06/2005] [Revised: 01/14/2006] [Accepted: 03/11/2006] [Indexed: 11/30/2022]
Abstract
Mechanical characteristics of circulation and vasculature, such as blood flow in combination with geometrical features, participate in the generation of several pathophysiological processes, such as development of blood vessel structure, chronic vessel tone regulation, atherosclerosis and others. We aim to briefly describe the basic mechanical and haemodynamic phenomena related to the forces applied to arterial walls, especially shear stresses and the shear-induced physiologic and pathophysiologic processes focusing on those related to atherosclerotic disease.
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Affiliation(s)
- Theodore G Papaioannou
- Unit of Biomedical Engineering, First Department of Cardiology, Hippocration Hospital, Medical School, National and Kapodistrian University of Athens, Iak. Patatsou 13, Nea Kipseli, 113 63 Athens, Greece.
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40
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Roberts WC. Facts and Ideas from Anywhere. Proc (Bayl Univ Med Cent) 2005; 18:285-94. [PMID: 16200186 PMCID: PMC1200738 DOI: 10.1080/08998280.2005.11928084] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022] Open
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