1
|
Manferdelli G, Narang BJ, Bourdillon N, Debevec T, Millet GP. Baroreflex sensitivity is blunted in hypoxia independently of changes in inspired carbon dioxide pressure in prematurely born male adults. Physiol Rep 2024; 12:e15857. [PMID: 38172085 PMCID: PMC10764294 DOI: 10.14814/phy2.15857] [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: 09/20/2023] [Revised: 10/19/2023] [Accepted: 10/23/2023] [Indexed: 01/05/2024] Open
Abstract
Premature birth may result in specific cardiovascular responses to hypoxia and hypercapnia, that might hamper high-altitude acclimatization. This study investigated the consequences of premature birth on baroreflex sensitivity (BRS) under hypoxic, hypobaric and hypercapnic conditions. Seventeen preterm born males (gestational age, 29 ± 1 weeks), and 17 age-matched term born adults (40 ± 0 weeks) underwent consecutive 6-min stages breathing different oxygen and carbon dioxide concentrations at both sea-level and high-altitude (3375 m). Continuous blood pressure and ventilatory parameters were recorded in normobaric normoxia (NNx), normobaric normoxic hypercapnia (NNx + CO2 ), hypobaric hypoxia (HHx), hypobaric normoxia (HNx), hypobaric normoxia hypercapnia (HNx + CO2 ), and hypobaric hypoxia with end-tidal CO2 clamped at NNx value (HHx + clamp). BRS was assessed using the sequence method. Across all conditions, BRS was lower in term born compared to preterm (13.0 ± 7.5 vs. 21.2 ± 8.8 ms⋅mmHg-1 , main group effect: p < 0.01) participants. BRS was lower in HHx compared to NNx in term born (10.5 ± 4.9 vs. 16.0 ± 6.0 ms⋅mmHg-1 , p = 0.05), but not in preterm (27.3 ± 15.7 vs. 17.6 ± 8.3 ms⋅mmHg-1 , p = 0.43) participants, leading to a lower BRS in HHx in term born compared to preterm (p < 0.01). In conclusion, this study reports a blunted response of BRS during acute high-altitude exposure without any influence of changes in inspired CO2 in healthy prematurely born adults.
Collapse
Affiliation(s)
| | - Benjamin J. Narang
- Department of Automation, Biocybernetics and RoboticsJožef Stefan InstituteLjubljanaSlovenia
- Faculty of SportUniversity of LjubljanaLjubljanaSlovenia
| | | | - Tadej Debevec
- Department of Automation, Biocybernetics and RoboticsJožef Stefan InstituteLjubljanaSlovenia
- Faculty of SportUniversity of LjubljanaLjubljanaSlovenia
| | | |
Collapse
|
2
|
JAVORKA K, HAŠKOVÁ K, CZIPPELOVÁ B, ZIBOLEN M, JAVORKA M. Baroreflex Sensitivity and Blood Pressure in Premature Infants – Dependence on Gestational Age, Postnatal Age and Sex. Physiol Res 2021; 70:S349-S356. [DOI: 10.33549/physiolres.934829] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
To characterize the differences in baroreflex sensitivity (BRS), blood pressure (BP), heart rate (HR) and respiration rate (RR) in preterm infants with a similar postconceptional age reached by various combinations of gestational and postnatal ages. To detect potential sex differences in assessed cardiovascular parameters. The study included 49 children (24 boys and 25 girls), postconceptional age 34.6±1.9 weeks. Two subgroups of infants were selected with the similar postconceptional age (PcA) and current weight, but differing in gestational (GA) and postnatal (PnA) ages, as well as two matched subgroups of boys and girls. Blood pressure (BP) was recorded continuously using Portapres device (FMS). A stationary segment of 250 beat-to-beat BP values was analyzed for each child. Baroreflex sensitivity (BRS) was calculated by cross-correlation sequence method. Despite the same PcA age and current weight, children with longer GA had higher BRS, diastolic and mean BP than children with shorter GA and longer PnA age. Postconceptional age in preterm infants is a parameter of maturation better predicting baroreflex sensitivity and blood pressure values compared to postnatal age. Sex related differences in BRS, BP, HR and RR were not found in our group of preterm infants.
Collapse
Affiliation(s)
- K JAVORKA
- Department of Physiology, Comenius University in Bratislava, Jessenius Faculty of Medicine, Martin, Slovak Republic
| | - K HAŠKOVÁ
- Clinic of Neonatology, Comenius University in Bratislava, Jessenius Faculty of Medicine and University Hospital, Martin, Slovak Republic
| | - B CZIPPELOVÁ
- Biomedical Centre Martin, Comenius University in Bratislava, Jessenius Faculty of Medicine, Martin, Slovak Republic
| | - M ZIBOLEN
- Clinic of Neonatology, Comenius University in Bratislava, Jessenius Faculty of Medicine and University Hospital, Martin, Slovak Republic
| | - M JAVORKA
- Department of Physiology, Comenius University in Bratislava, Jessenius Faculty of Medicine, Martin, Slovak Republic
| |
Collapse
|
3
|
Duenas-Meza E, Escamilla-Gil MI, Bazurto-Zapata MA, Caparo E, Suarez Cuartas M, Rincón Martínez L, Pernett Buenaver L, Rojas Ortega A, Torres J, Restrepo-Gualteros S, Parra Buitrago A, Gonzalez-Garcia M. Intermittent Hypoxia and Respiratory Patterns During Sleep of Preterm Infants Aged 3 to 18 Months Residing at High Altitudes. Sleep 2021; 45:6354695. [PMID: 34409457 DOI: 10.1093/sleep/zsab208] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 06/05/2021] [Indexed: 11/13/2022] Open
Abstract
STUDY OBJECTIVES the aim of this study was to determine the impact of apneas on oxygen saturation and the presence of intermittent hypoxia, during sleep of preterm infants (PTIs) born at high altitudes and compare with full-term infants (FTIs) at the same altitude. METHODS PTIs and FTIs from 3 to 18 months were included. They were divided into three age groups: 3-4 months (Group 1); 6-7 months (Group 2) and 10-18 months (Group 3). Polysomnography parameters and oxygenation indices were evaluated. Intermittent hypoxia was defined as brief, repetitive cycles of decreased oxygen saturation. Kruskal-Wallis test for multiple comparisons, t-test or Mann-Whitney U test were used. RESULTS 127 PTI and 175 FTI were included. Total apnea-hypopnea index (AHI) was higher in PTI that FTI in all age groups (Group 1: 33.5/h vs. 12.8/h, p=0.042; Group 2: 27.0/h vs. 7.4/h, p<0.001 and Group 3: 11.6/h vs. 3.1/h, p<0.001). In Group 3, central-AHI (8.0/h vs. 2.3/h, p<0.001) and obstructive-AHI (1.8/h vs. 0.6/h, p<0.008) were higher in PTI than FTI. T90 (7.0% vs. 0.5, p<0.001), oxygen desaturation index (39.8/h vs. 11.3, p<0.001) were higher in PTI than FTI, nadir SpO2 (70.0% vs. 80.0, p<0.001) was lower in PTI . CONCLUSION At high altitude, compared to FTI, PTI have a higher rate of respiratory events, greater desaturation and a delayed resolution of these conditions, suggesting the persistence of intermittent hypoxia during the first 18 months of life. This indicates the need for follow-up of these infants for timely diagnosis and treatment of respiratory disturbances during sleep.
Collapse
Affiliation(s)
- Elida Duenas-Meza
- Fundación Neumológica Colombiana.,Universidad de La Sabana.,Fundación Cardioinfantil-Instituto de Cardiología
| | | | | | | | - Miguel Suarez Cuartas
- Fundación Neumológica Colombiana.,Universidad de La Sabana.,Fundación Cardioinfantil-Instituto de Cardiología
| | | | - Lisbeth Pernett Buenaver
- Fundación Neumológica Colombiana.,Universidad de La Sabana.,Fundación Cardioinfantil-Instituto de Cardiología
| | | | | | | | - Andrea Parra Buitrago
- Fundación Neumológica Colombiana.,Universidad de La Sabana.,Fundación Cardioinfantil-Instituto de Cardiología
| | | |
Collapse
|
4
|
Prone sleeping affects cardiovascular control in preterm infants in NICU. Pediatr Res 2021; 90:197-204. [PMID: 33173173 DOI: 10.1038/s41390-020-01254-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/28/2020] [Accepted: 10/06/2020] [Indexed: 11/08/2022]
Abstract
BACKGROUND Prone sleeping is used in preterm infants undergoing intensive care to improve respiratory function, but evidence suggests that this position may compromise autonomic cardiovascular control. To test this hypothesis, this study assessed the effects of the prone sleeping position on cardiovascular control in preterm infants undergoing intensive care treatment during early postnatal life. METHODS Fifty-six preterm infants, divided into extremely preterm (gestational age (GA) 24-28 weeks, n = 23) and very preterm (GA 29-34 weeks, n = 33) groups, were studied weekly for 3 weeks in prone and supine positions, during quiet and active sleep. Heart rate (HR) and non-invasive blood pressure (BP) were recorded and autonomic measures of HR variability (HRV), BP variability (BPV), and baroreflex sensitivity (BRS) using frequency analysis in low (LF) and high (HF) bands were assessed. RESULTS During the first 3 weeks, prone sleeping increased HR, reduced BRS, and increased HF BPV compared to supine. LF and HF HRV were also lower prone compared to supine in very preterm infants. Extremely preterm infants had the lowest HRV and BRS measures, and the highest HF BPV. CONCLUSIONS Prone sleeping dampens cardiovascular control in early postnatal life in preterm infants, having potential implications for BP regulation in infants undergoing intensive care.
Collapse
|
5
|
Bates ML, Levy PT, Nuyt AM, Goss KN, Lewandowski AJ, McNamara PJ. Adult Cardiovascular Health Risk and Cardiovascular Phenotypes of Prematurity. J Pediatr 2020; 227:17-30. [PMID: 32931771 DOI: 10.1016/j.jpeds.2020.09.019] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/21/2020] [Revised: 08/25/2020] [Accepted: 09/09/2020] [Indexed: 02/07/2023]
Affiliation(s)
- Melissa L Bates
- Department of Health and Human Physiology, University of Iowa, Iowa City, IA; Division of Neonatology, Stead Family Department of Pediatrics, University of Iowa, Iowa City, IA
| | - Philip T Levy
- Division of Newborn Medicine, Department of Pediatrics, Boston Children's Hospital, Harvard Medical School, Boston, MA.
| | - Anne Monique Nuyt
- Division of Neonatology, Department of Pediatrics, CHU Sainte-Justine, Faculty of Medicine, Université de Montréal, Montréal, Quebec, Canada
| | - Kara N Goss
- Department of Pediatrics, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI; Department of Medicine, School of Medicine and Public Health, University of Wisconsin-Madison, Madison, WI
| | - Adam J Lewandowski
- Oxford Cardiovascular Clinical Research Facility, Division of Cardiovascular Medicine, Radcliffe Department of Medicine, University of Oxford, Oxford, UK
| | - Patrick J McNamara
- Division of Neonatology, Stead Family Department of Pediatrics, University of Iowa, Iowa City, IA
| |
Collapse
|
6
|
Suppiej A, Vedovelli L, Boschiero D, Bolzon M, Cainelli E. Abnormal heart rate variability at school age in survivors of neonatal hypoxic-ischemic encephalopathy managed with therapeutic hypothermia. Eur J Paediatr Neurol 2020; 29:66-70. [PMID: 32863129 DOI: 10.1016/j.ejpn.2020.08.004] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/28/2020] [Revised: 07/13/2020] [Accepted: 08/18/2020] [Indexed: 01/08/2023]
Abstract
BACKGROUND AND OBJECTIVE Major deficits in the autonomic nervous system function, detected by measuring heart rate variability (HRV), are reported in neonatal hypoxic-ischemic encephalopathy (HIE)). However, it is unknown if they will recover in the long-term. Because of the possible implications for the neurological outcome, this study aimed to evaluate the HRV at school age, in a cohort of children who survived HIE managed with therapeutic hypothermia. METHODS A cross-sectional study of HRV in 40 children: 20 HIE survivors and 20 healthy peers. All underwent 5-min plethysmography using the PPG Stress Flow device (BioTekna Italy). Absolute and normalized HRV spectral power in the very low frequency (VLF), low frequency (LF), and high frequency (HF) bands and total power were compared between patients and healthy children. The outcome evaluation included neurological, cognitive (WISC-IV), and psychosocial (Parent Stress Index-Short Form-PSI-SF and psychosocial interview) measures. RESULTS All mean HRV values were significantly higher in survivors of HIE, compared to healthy peers, with the larger effect size for the HF band (Total Power 8.57 ± 0.59 vs 7.82 ± 0.77 ms2, p .003 ES 0.21; HF 7.82 + 0.77 vs 8.57 + 0.59 ms2, p .001 EF 0.24). None of the children had major health, neurological and psychosocial (PSI-SF/interview) problems. The IQ (WISC-IV) was normal in 17/20 patients, borderline in 2, and <70 in 1. CONCLUSIONS HRV measures highlight autonomic dysfunction at school age in survivors of neonatal HIE, in the absence of major neurodevelopmental and psychosocial problems. The significance of this finding for children's future life needs further neuropsychiatric investigations and longer follow-up.
Collapse
Affiliation(s)
- A Suppiej
- Department of Medical Sciences, Paediatric Section, University of Ferrara, Italy; Pediatric University Hospital, Padova, Italy.
| | - L Vedovelli
- Unit of Biostatistics, Epidemiology and Public Health, Department of Cardiac, Thoracic, Vascular Sciences, and Public Health, University of Padova, Italy
| | - D Boschiero
- BIOTEKNA Biomedical Technologies, Venice, Italy
| | - M Bolzon
- Neuro-Intensive Care and Anaesthesiology, University Hospital, Borgo Trento Hospital, Verona, Italy
| | - E Cainelli
- Pediatric University Hospital, Padova, Italy; Department of Developmental and Social Psychology, University of Padova, Italy
| |
Collapse
|
7
|
Dissanayake HU, McMullan RL, Gordon A, Caterson ID, Celermajer DS, Phang M, Raynes-Greenow C, Skilton MR, Polson JW. Noninvasive assessment of autonomic function in human neonates born at the extremes of fetal growth spectrum. Physiol Rep 2019; 6:e13682. [PMID: 29687617 PMCID: PMC5913591 DOI: 10.14814/phy2.13682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 03/22/2018] [Indexed: 01/23/2023] Open
Abstract
Birth weight is associated with adult cardiovascular disease, such that those at both ends of the spectrum are at increased risk. This may be driven in part by modification to autonomic control, a mechanistic contributor to hypertension. However, birth weight is a relatively crude surrogate of fetal growth; and newborn body composition may more accurately identify the "at risk" infant. Accordingly, we sought to determine whether newborns with high or low body fat have altered autonomic control of vasomotor function and cardiac contractility. Body fat was assessed by air-displacement plethysmography <24 h postnatal. Measures of spontaneous baroreflex sensitivity (sBRS), blood pressure variability (BPV), and dP/dtmax variability were compared between newborns categorized according to established body fat percentiles: high body fat (HBF, >90th percentile, n = 7), low body fat (LBF, ≤10th percentile, n = 12), and normal body fat (control, >25th to ≤75th percentile, n = 23). BPV was similar across body fat percentiles; similarly, low frequency dP/dtmax variability was similar across body fat percentiles. sBRS was reduced in HBF compared to controls (11.0 ± 6.0 vs. 20.1 ± 9.4 msec/mmHg, P = 0.03), but LBF did not differ (18.4 ± 6.0 msec/mmHg, P = 0.80). Across the entire body fat spectrum (n = 62), there was a nonlinear association between newborn body fat and sBRS (P = 0.03) that was independent of birth weight (P = 0.04). Autonomic modulation of vasomotor function and cardiac contractility in the newborn did not differ by body fat, but newborns born with high body fat show depressed baroreflex sensitivity.
Collapse
Affiliation(s)
- Hasthi U Dissanayake
- Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, The University of Sydney, Sydney, New South Wales, Australia.,Sydney Medical School, D17- Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia
| | - Rowena L McMullan
- Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, The University of Sydney, Sydney, New South Wales, Australia.,Sydney Medical School, D17- Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia.,Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Adrienne Gordon
- Sydney Medical School, D17- Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia.,Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Ian D Caterson
- Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, The University of Sydney, Sydney, New South Wales, Australia
| | - David S Celermajer
- Sydney Medical School, D17- Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia.,Royal Prince Alfred Hospital, Sydney, New South Wales, Australia
| | - Melinda Phang
- Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, The University of Sydney, Sydney, New South Wales, Australia
| | - Camille Raynes-Greenow
- Sydney School of Public Health, The University of Sydney, Sydney, New South Wales, Australia
| | - Michael R Skilton
- Boden Institute of Obesity, Nutrition, Exercise & Eating Disorders, The University of Sydney, Sydney, New South Wales, Australia.,Sydney Medical School, D17- Charles Perkins Centre, The University of Sydney, Sydney, New South Wales, Australia
| | - Jaimie W Polson
- School of Medical Sciences & Bosch Institute, The University of Sydney, Sydney, New South Wales, Australia
| |
Collapse
|
8
|
Badurdeen S, Roberts C, Blank D, Miller S, Stojanovska V, Davis P, Hooper S, Polglase G. Haemodynamic Instability and Brain Injury in Neonates Exposed to Hypoxia⁻Ischaemia. Brain Sci 2019; 9:brainsci9030049. [PMID: 30818842 PMCID: PMC6468566 DOI: 10.3390/brainsci9030049] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 02/24/2019] [Accepted: 02/26/2019] [Indexed: 11/23/2022] Open
Abstract
Brain injury in the asphyxic newborn infant may be exacerbated by delayed restoration of cardiac output and oxygen delivery. With increasing severity of asphyxia, cerebral autoregulatory responses are compromised. Further brain injury may occur in association with high arterial pressures and cerebral blood flows following the restoration of cardiac output. Initial resuscitation aims to rapidly restore cardiac output and oxygenation whilst mitigating the impact of impaired cerebral autoregulation. Recent animal studies have indicated that the current standard practice of immediate umbilical cord clamping prior to resuscitation may exacerbate injury. Resuscitation prior to umbilical cord clamping confers several haemodynamic advantages. In particular, it retains the low-resistance placental circuit that mitigates the rebound hypertension and cerebrovascular injury. Prolonged cerebral hypoxia–ischaemia is likely to contribute to further perinatal brain injury, while, at the same time, tissue hyperoxia is associated with oxidative stress. Efforts to monitor and target cerebral flow and oxygen kinetics, for example, using near-infrared spectroscopy, are currently being evaluated and may facilitate development of novel resuscitation approaches.
Collapse
Affiliation(s)
- Shiraz Badurdeen
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
- Newborn Research Centre, The Royal Women's Hospital, Melbourne 3052, Australia.
| | - Calum Roberts
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Douglas Blank
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Suzanne Miller
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Vanesa Stojanovska
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Peter Davis
- Newborn Research Centre, The Royal Women's Hospital, Melbourne 3052, Australia.
| | - Stuart Hooper
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| | - Graeme Polglase
- The Ritchie Centre, Hudson Institute of Medical Research, Monash University, Melbourne 3168, Australia.
| |
Collapse
|
9
|
South AM, Shaltout HA, Washburn LK, Hendricks AS, Diz DI, Chappell MC. Fetal programming and the angiotensin-(1-7) axis: a review of the experimental and clinical data. Clin Sci (Lond) 2019; 133:55-74. [PMID: 30622158 PMCID: PMC6716381 DOI: 10.1042/cs20171550] [Citation(s) in RCA: 77] [Impact Index Per Article: 15.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2018] [Revised: 11/20/2018] [Accepted: 12/03/2018] [Indexed: 02/07/2023]
Abstract
Hypertension is the primary risk factor for cardiovascular disease that constitutes a serious worldwide health concern and a significant healthcare burden. As the majority of hypertension has an unknown etiology, considerable research efforts in both experimental models and human cohorts has focused on the premise that alterations in the fetal and perinatal environment are key factors in the development of hypertension in children and adults. The exact mechanisms of how fetal programming events increase the risk of hypertension and cardiovascular disease are not fully elaborated; however, the focus on alterations in the biochemical components and functional aspects of the renin-angiotensin (Ang) system (RAS) has predominated, particularly activation of the Ang-converting enzyme (ACE)-Ang II-Ang type 1 receptor (AT1R) axis. The emerging view of alternative pathways within the RAS that may functionally antagonize the Ang II axis raise the possibility that programming events also target the non-classical components of the RAS as an additional mechanism contributing to the development and progression of hypertension. In the current review, we evaluate the potential role of the ACE2-Ang-(1-7)-Mas receptor (MasR) axis of the RAS in fetal programming events and cardiovascular and renal dysfunction. Specifically, the review examines the impact of fetal programming on the Ang-(1-7) axis within the circulation, kidney, and brain such that the loss of Ang-(1-7) expression or tone, contributes to the chronic dysregulation of blood pressure (BP) and cardiometabolic disease in the offspring, as well as the influence of sex on potential programming of this pathway.
Collapse
Affiliation(s)
- Andrew M South
- Department of Pediatrics, Section of Nephrology, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Epidemiology and Prevention, Division of Public Health Sciences, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| | - Hossam A Shaltout
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Obstetrics and Gynecology, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Pharmacology and Toxicology, School of Pharmacy, University of Alexandria, Egypt
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Surgery, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| | - Lisa K Washburn
- Department of Pediatrics, Section of Nephrology, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| | - Alexa S Hendricks
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| | - Debra I Diz
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Surgery, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| | - Mark C Chappell
- Cardiovascular Sciences Center, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A.
- Hypertension and Vascular Research, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
- Department of Surgery, Wake Forest School of Medicine, 526 Vine Street, Winston Salem, NC 27157, U.S.A
| |
Collapse
|
10
|
Denisova K. Neurobiology, not artifacts: Challenges and guidelines for imaging the high risk infant. Neuroimage 2019; 185:624-640. [DOI: 10.1016/j.neuroimage.2018.07.023] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2017] [Revised: 07/07/2018] [Accepted: 07/10/2018] [Indexed: 12/21/2022] Open
|
11
|
Autonomic dysfunction in programmed hypertension. J Hum Hypertens 2018; 33:267-276. [PMID: 30518808 DOI: 10.1038/s41371-018-0142-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Revised: 10/31/2018] [Accepted: 11/21/2018] [Indexed: 02/07/2023]
Abstract
Hypertension is an important modifiable risk factor for cardiovascular diseases. Its high prevalence, combined with the significant morbidity and mortality associated with secondary complications, make it a major public health concern. Despite decades of research, over 95% of all cases of hypertension remain of unknown etiology, necessitating that treatments target the established symptoms and not the cause. One of the important recent advances in hypertension research is an understanding that hypertension often may have a developmental origin. A substantial body of evidence indicates that exposure to an adverse intrauterine environment during critical periods of development may predispose an individual to develop hypertension later in life. A causative mechanism has yet to be identified, but may include epigenetic modifications, and/or alterations in renal, vascular or autonomic cardiovascular functions. This review will present evidence regarding changes in autonomic activity as a possible causative pathophysiological mechanism underlying the development of programmed hypertension. In man, low birth weight is the best-known risk factor for hypertension of developmental origins, although this is a broad surrogate measure for intrauterine adversity. This review will include clinical studies across the lifespan that have investigated autonomic function in individuals with fetal growth restriction and those born preterm. A determination of whether altered autonomic function is seen in these individuals in early life is imperative, as hypertensive disorders that have their origins in utero, and that can be identified early, will open the door to risk stratification, and the development of new strategies that prevent or specifically target these mechanisms.
Collapse
|
12
|
Bennet L, Walker DW, Horne RSC. Waking up too early - the consequences of preterm birth on sleep development. J Physiol 2018; 596:5687-5708. [PMID: 29691876 DOI: 10.1113/jp274950] [Citation(s) in RCA: 57] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2017] [Accepted: 03/16/2017] [Indexed: 12/12/2022] Open
Abstract
Good quality sleep of sufficient duration is vital for optimal physiological function and our health. Sleep deprivation is associated with impaired neurocognitive function and emotional control, and increases the risk for cardiometabolic diseases, obesity and cancer. Sleep develops during fetal life with the emergence of a recognisable pattern of sleep states in the preterm fetus associated with the development, maturation and connectivity within neural networks in the brain. Despite the physiological importance of sleep, surprisingly little is known about how sleep develops in individuals born preterm. Globally, an estimated 15 million babies are born preterm (<37 weeks gestation) each year, and these babies are at significant risk of neural injury and impaired brain development. This review discusses how sleep develops during fetal and neonatal life, how preterm birth impacts on sleep development to adulthood, and the factors which may contribute to impaired brain and sleep development, leading to altered neurocognitive, behavioural and motor capabilities in the infant and child. Going forward, the challenge is to identify specific risk factors for impaired sleep development in preterm babies to allow for the design of interventions that will improve the quality and quantity of sleep throughout life.
Collapse
Affiliation(s)
- Laura Bennet
- Department of Physiology, The University of Auckland, Auckland, New Zealand
| | - David W Walker
- School of Health and Biomedical Sciences, RMIT University, Bundoora, Victoria, Australia
| | - Rosemary S C Horne
- The Ritchie Centre, Department of Paediatrics, Monash University and Hudson Institute of Medical Research, Melbourne, Victoria, Australia
| |
Collapse
|
13
|
Haraldsdottir K, Watson AM, Goss KN, Beshish AG, Pegelow DF, Palta M, Tetri LH, Barton GP, Brix MD, Centanni RM, Eldridge MW. Impaired autonomic function in adolescents born preterm. Physiol Rep 2018; 6:e13620. [PMID: 29595875 PMCID: PMC5875539 DOI: 10.14814/phy2.13620] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 01/25/2018] [Indexed: 01/01/2023] Open
Abstract
Preterm birth temporarily disrupts autonomic nervous system (ANS) development, and the long-term impacts of disrupted fetal development are unclear in children. Abnormal cardiac ANS function is associated with worse health outcomes, and has been identified as a risk factor for cardiovascular disease. We used heart rate variability (HRV) in the time domain (standard deviation of RR intervals, SDRR; and root means squared of successive differences, RMSSD) and frequency domain (high frequency, HF; and low frequency, LF) at rest, as well as heart rate recovery (HRR) following maximal exercise, to assess autonomic function in adolescent children born preterm. Adolescents born preterm (less than 36 weeks gestation at birth) in 2003 and 2004 and healthy age-matched full-term controls participated. Wilcoxon Rank Sum tests were used to compare variables between control and preterm groups. Twenty-one adolescents born preterm and 20 term-born controls enrolled in the study. Preterm-born subjects had lower time-domain HRV, including SDRR (69.1 ± 33.8 vs. 110.1 ± 33.0 msec, respectively, P = 0.008) and RMSSD (58.8 ± 38.2 vs. 101.5 ± 36.2 msec, respectively, P = 0.012), with higher LF variability in preterm subjects. HRR after maximal exercise was slower in preterm-born subjects at 1 min (30 ± 12 vs. 39 ± 9 bpm, respectively, P = 0.013) and 2 min (52 ± 10 vs. 60 ± 10 bpm, respectively, P = 0.016). This study is the first report of autonomic dysfunction in adolescents born premature. Given prior association of impaired HRV with adult cardiovascular disease, additional investigations into the mechanisms of autonomic dysfunction in this population are warranted.
Collapse
Affiliation(s)
- Kristin Haraldsdottir
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
- Department of KinesiologyUniversity of WisconsinMadisonWisconsin
| | - Andrew M. Watson
- Department of Orthopedics & RehabilitationUniversity of WisconsinMadisonWisconsin
| | - Kara N. Goss
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
- Department of MedicineUniversity of WisconsinMadisonWisconsin
| | - Arij G. Beshish
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
| | | | - Mari Palta
- Department of Biostatistics and Medical InformaticsUniversity of WisconsinMadisonWisconsin
| | - Laura H. Tetri
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
| | | | - Melissa D. Brix
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
| | | | - Marlowe W. Eldridge
- Department of PediatricsUniversity of WisconsinMadisonWisconsin
- Department of KinesiologyUniversity of WisconsinMadisonWisconsin
| |
Collapse
|
14
|
Cardiovascular autonomic dysfunction in sudden infant death syndrome. Clin Auton Res 2018; 28:535-543. [PMID: 29299712 DOI: 10.1007/s10286-017-0490-y] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Accepted: 12/12/2017] [Indexed: 10/18/2022]
Abstract
A failure of cardiorespiratory control mechanisms, together with an impaired arousal response from sleep, are believed to play an important role in the final event of sudden infant death syndrome (SIDS). The 'triple risk model' describes SIDS as an event that results from the intersection of three overlapping factors: (1) a vulnerable infant, (2) a critical developmental period in homeostatic control and (3) an exogenous stressor. In an attempt to understand how the triple risk hypothesis is related to infant cardiorespiratory physiology, many researchers have examined how the known risk and protective factors for SIDS alter infant cardiovascular control during sleep. This review discusses the association between the three components of the triple risk hypothesis and major risk factors for SIDS, such as prone sleeping, maternal smoking, together with three "protective" factors, and cardiovascular control during sleep in infants, and discusses their potential involvement in SIDS.
Collapse
|
15
|
Fyfe KL, Yiallourou SR, Wong FY, Odoi A, Walker AM, Horne RSC. The Effect of Gestational Age at Birth on Post-Term Maturation of Heart Rate Variability. Sleep 2015; 38:1635-44. [PMID: 25902805 DOI: 10.5665/sleep.5064] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2014] [Accepted: 03/14/2015] [Indexed: 12/19/2022] Open
Abstract
STUDY OBJECTIVE Preterm birth delays maturation of autonomic cardiovascular control, reflected in reduced heart rate variability (HRV) in preterm compared to term infants at term-equivalent age. It has been suggested that immature cardiovascular control contributes to the increased risk for the sudden infant death syndrome (SIDS) in preterm infants. However, the effects of prone sleeping, the major SIDS risk factor, and of gestational age (GA) at birth on HRV have not been assessed in preterm infants beyond term-equivalent age. SUBJECTS AND METHODS Very preterm (n = 21; mean GA 29.4 ± 0.3 weeks), preterm (n = 14; mean GA 33.5 ± 0.3 weeks), and term (n = 17; mean GA 40.1 ± 0.3 weeks) infants were recruited and underwent daytime polysomnography at 2-4 weeks, 2-3 months, and 5-6 months post-term corrected age (CA). Infants slept both supine and prone. HRV was assessed in the low frequency (LF) and high frequency (HF) ranges. RESULTS There was no effect of prone sleeping on HRV parameters in either preterm group. In term infants LF/HF was significantly elevated in the prone position in AS at 2-4 weeks (P < 0.05). HF HRV was significantly reduced (P < 0.05) and LF/HF increased (P < 0.05) in very preterm compared to both preterm and term infants at 2-3 months CA. CONCLUSION Prone sleeping did not significantly impact on heart rate variability (HRV) in preterm infants. However, reduced maturation of high frequency HRV in very preterm infants resulted in significantly altered sympathovagal balance at 2-3 months corrected age, the age of peak sudden infant death syndrome (SIDS) risk. This may contribute to the increased risk of SIDS in infants born at earlier gestational age.
Collapse
Affiliation(s)
- Karinna L Fyfe
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| | - Stephanie R Yiallourou
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| | - Flora Y Wong
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia.,Monash Newborn, Monash Medical Centre, Melbourne, Australia
| | - Alexsandria Odoi
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia
| | - Adrian M Walker
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia
| | - Rosemary S C Horne
- The Ritchie Centre, Hudson Institute of Medical Research and Monash University, Melbourne, Australia.,Department of Paediatrics, Monash University, Melbourne, Australia
| |
Collapse
|
16
|
Michelet D, Arslan O, Hilly J, Mangalsuren N, Brasher C, Grace R, Bonnard A, Malbezin S, Nivoche Y, Dahmani S. Intraoperative changes in blood pressure associated with cerebral desaturation in infants. Paediatr Anaesth 2015; 25:681-8. [PMID: 25929346 DOI: 10.1111/pan.12671] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/02/2015] [Indexed: 11/26/2022]
Abstract
BACKGROUND Intraoperative hypotension has been linked to poor postoperative neurological outcomes. However, the definition of hypotension remains controversial in children. We sought to determine arterial blood pressure threshold values associated with cerebral desaturation in infants. METHODS After ethics committee approval, infants younger than 3 months were included in this prospective observational study. Cerebral saturation was assessed using near-infrared spectroscopy. The primary goal of the study was to determine percentage reductions in intraoperative systolic blood pressure (SBP) and mean blood pressure (MBP) associated with decreases in cerebral blood oxygen saturation of >20%, when compared to baseline. Analyses were performed using a bootstrap receiving operator characteristic (ROC) curves with determination of the gray zone. RESULTS Sixty patients were recruited and 960 measurement points were recorded. Fifty-nine data points (6.1%) recorded cerebral desaturation of >20% when compared to baseline. The areas under the ROC curves were 0.79 (0.74-0.84) and 0.67 (0.6-0.75) for percentage decreases in SBP and MBP, respectively. Gray zone values with false-positive and negative rates <10% were SBP decreases of 20.5% and 37.5%, respectively, and MBP decreases of 15.5% and 44.5%, respectively. CONCLUSION Our results indicate that falls in noninvasive systolic blood pressure of <20% from baseline are associated with a <10% chance of cerebral desaturation in neonates and infants <3 months of age undergoing noncardiac surgery. As such, maintaining systolic blood pressure above this threshold value appears a valid clinical target.
Collapse
Affiliation(s)
- Daphné Michelet
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Ozkan Arslan
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Julie Hilly
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Nyamjargal Mangalsuren
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Christopher Brasher
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Robert Grace
- Department of Anesthesia, Intensive Care and Peri-operative Medicine, Cairns Hospital, Cairns, Qld, Australia
| | - Arnaud Bonnard
- Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France.,Department of General and Urological Surgery, AP-HP, Robert Debré University Hospital, Paris Diderot University, Paris, France
| | - Serge Malbezin
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Yves Nivoche
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France
| | - Souhayl Dahmani
- Department of Anesthesia, Intensive Care and Pain Management, AP-HP, Robert Debré University Hospital, Paris, France.,Paris Diderot University (Paris VII), Pres Paris Sorbonne Cité, Paris, France.,Department of Anesthesia, Intensive Care and Peri-operative Medicine, Cairns Hospital, Cairns, Qld, Australia.,University and Hospital Department PROTECT, Robert Debré University Hospital, Paris, France
| |
Collapse
|
17
|
Mathewson KJ, Van Lieshout RJ, Saigal S, Morrison KM, Boyle MH, Schmidt LA. Autonomic Functioning in Young Adults Born at Extremely Low Birth Weight. Glob Pediatr Health 2015; 2:2333794X15589560. [PMID: 27335960 PMCID: PMC4784639 DOI: 10.1177/2333794x15589560] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Autonomic functioning is altered in infants born at extremely low birth weight (ELBW; <1000 g), but we know little about how such alterations manifest in adulthood. We examined associations between birth weight and resting heart rate (R-R interval), high-frequency (HF) and low-frequency (LF) heart rate variability, and systolic (SBP) and diastolic (DBP) blood pressure, in 60 participants (ages 22-26) born at ELBW and free of major neurosensory impairment, and 79 controls born at normal birth weight (NBW; >2500 g). HF in the smallest-born ELBW participants was significantly lower than in NBW controls. In both groups, greater birth weight was associated with higher HF. Among ELBW survivors, lower birth weight predicted faster heart rate and higher DBP, but neither heart rate nor DBP appeared to be well-coordinated with baroreflex activity (LF), the principal mechanism for short-term blood pressure regulation. Adult autonomic regulation may be significantly altered in those born extremely preterm.
Collapse
|
18
|
Yiallourou SR, Wallace EM, Miller SL, Horne RSC. Effects of intrauterine growth restriction on sleep and the cardiovascular system: The use of melatonin as a potential therapy? Sleep Med Rev 2015; 26:64-73. [PMID: 26140865 DOI: 10.1016/j.smrv.2015.04.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2014] [Revised: 04/14/2015] [Accepted: 04/14/2015] [Indexed: 12/28/2022]
Abstract
Intrauterine growth restriction (IUGR) complicates 5-10% of pregnancies and is associated with increased risk of preterm birth, mortality and neurodevelopmental delay. The development of sleep and cardiovascular control are closely coupled and IUGR is known to alter this development. In the long-term, IUGR is associated with altered sleep and an increased risk of hypertension in adulthood. Melatonin plays an important role in the sleep-wake cycle. Experimental animal studies have shown that melatonin therapy has neuroprotective and cardioprotective effects in the IUGR fetus. Consequently, clinical trials are currently underway to assess the short and long term effects of antenatal melatonin therapy in IUGR pregnancies. Given melatonin's role in sleep regulation, this hormone could affect the developing infants' sleep-wake cycle and cardiovascular function after birth. In this review, we will 1) examine the role of melatonin as a therapy for IUGR pregnancies and the potential implications on sleep and the cardiovascular system; 2) examine the development of sleep-wake cycle in fetal and neonatal life; 3) discuss the development of cardiovascular control during sleep; 4) discuss the effect of IUGR on sleep and the cardiovascular system and 5) discuss the future implications of melatonin therapy in IUGR pregnancies.
Collapse
Affiliation(s)
- Stephanie R Yiallourou
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia.
| | - Euan M Wallace
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Suzanne L Miller
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Obstetrics and Gynaecology, Monash University, Melbourne, Australia
| | - Rosemary S C Horne
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia
| |
Collapse
|
19
|
Fyfe KL, Yiallourou SR, Wong FY, Odoi A, Walker AM, Horne RSC. Gestational age at birth affects maturation of baroreflex control. J Pediatr 2015; 166:559-65. [PMID: 25556016 DOI: 10.1016/j.jpeds.2014.11.026] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/07/2014] [Revised: 09/29/2014] [Accepted: 11/11/2014] [Indexed: 11/29/2022]
Abstract
OBJECTIVES To assess the effect of prone sleeping, the major risk factor for sudden infant death syndrome, in the control of blood pressure (BP) in preterm infants born across a range of gestational ages. STUDY DESIGN Daytime polysomnography was performed at 2-4 weeks, 2-3 months, and 5-6 months postterm age. The participants were 21 very preterm (mean gestation 29.4 ± 0.3 weeks), 14 preterm (mean gestation 33.1 ± 0.3 weeks), and 17 term (mean gestation 40.1 ± 0.3 weeks). BP was measured via a Finometer cuff (Finapres Medical Systems, Amsterdam, The Netherlands) placed around the wrist. Data were recorded both supine and prone. Baroreflex sensitivity (BRS) was calculated via cross-spectral analysis of spontaneous fluctuations in BP. RESULTS BRS was lower in the prone position in very preterm infants at 2-4 weeks in active sleep (P < .05). Maturation of BRS was delayed in very preterm compared with both preterm and term infants. CONCLUSIONS Maturation of BRS after term-equivalent age is altered in very preterm infants. Reduced BRS may result in an impaired ability of very preterm infants to respond to cardiovascular stress during infancy and may predispose them to cardiovascular disease later in life.
Collapse
Affiliation(s)
- Karinna L Fyfe
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia
| | - Stephanie R Yiallourou
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia
| | - Flora Y Wong
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia; Monash Newborn, Monash Health, Melbourne, Victoria, Australia
| | - Alexsandria Odoi
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia
| | - Adrian M Walker
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia
| | - Rosemary S C Horne
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Victoria, Australia; The Department of Paediatrics, Monash University, Melbourne, Victoria, Australia.
| |
Collapse
|
20
|
Fyfe KL, Yiallourou SR, Wong FY, Odoi A, Walker AM, Horne RSC. Cerebral oxygenation in preterm infants. Pediatrics 2014; 134:435-45. [PMID: 25157010 DOI: 10.1542/peds.2014-0773] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
BACKGROUND AND OBJECTIVE Prone sleeping is a major risk factor for sudden infant death syndrome (SIDS) and preterm infants are at significantly increased risk. In term infants, prone sleeping is associated with reduced mean arterial pressure (MAP) and cerebral tissue oxygenation index (TOI). However, little is known about the effects of sleeping position on TOI and MAP in preterm infants. We aimed to examine TOI and MAP in preterm infants after term-equivalent age, during the period of greatest SIDS risk. METHODS Thirty-five preterm and 17 term infants underwent daytime polysomnography, including measurement of TOI (NIRO-200 spectrophotometer, Hamamatsu Photonics KK, Japan) and MAP (Finapress Medical Systems, Amsterdam, Netherlands) at 2 to 4 weeks, 2 to 3 months, and 5 to 6 months postterm age. Infants slept prone and supine in active and quiet sleep. The effects of sleep state and position were determined by using 2-way repeated measures analysis of variance and of preterm birth by using 2-way analysis of variance. RESULTS In preterm infants, TOI was significantly lower when prone compared with supine in both sleep states at all ages (P < .05). Notably, TOI was significantly lower in preterm compared with term infants at 2 to 4 weeks, in both positions (P < .05), and at 2 to 3 months when prone (P < .001), in both sleep states. MAP was also lower in preterm infants in the prone position at 2 to 3 months (P < .01). CONCLUSIONS Cerebral oxygenation is reduced in the prone position in preterm infants and is lower compared with age-matched term infants, predominantly in the prone position when MAP is also reduced. This may contribute to their increased SIDS risk.
Collapse
Affiliation(s)
- Karinna L Fyfe
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia; and
| | - Stephanie R Yiallourou
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia; and
| | - Flora Y Wong
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia; and Monash Newborn, Monash Medical Centre, Melbourne, Australia
| | - Alexsandria Odoi
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia
| | - Adrian M Walker
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia
| | - Rosemary S C Horne
- The Ritchie Centre, Monash Institute of Medical Research and Prince Henry's Institute and Monash University, Melbourne, Australia; Department of Paediatrics, Monash University, Melbourne, Australia; and
| |
Collapse
|
21
|
No changes in cerebellar microvessel length density in sudden infant death syndrome: implications for pathogenetic mechanisms. J Neuropathol Exp Neurol 2014; 73:312-23. [PMID: 24607967 DOI: 10.1097/nen.0000000000000055] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
Abstract
Sudden infant death syndrome (SIDS) is the leading cause of mortality in infants younger than 1 year in developed countries, but its primary cause remains unknown. Some studies suggest that there may be hypoxia in the cerebellum in SIDS subjects, but mean total Purkinje cell numbers in SIDS versus controls was recently found not to be different. Probably the best marker for chronic hypoxia in a brain region is the microvessel length per unit volume of tissue, that is, the microvessel length density (MLD). Here, we investigated MLDs using a rigorous design-based stereologic approach in all cell layers and white matter in postmortem cerebella from 9 SIDS cases who died between ages 2 and 10 months and from 14 control children, 9 of which were age- and sex- matched to the SIDS cases. We found no differences either in mean MLDs in the cerebellar layers between the SIDS cases and the controls or between controls with a low likelihood of hypoxia and those with a higher likelihood of hypoxia. Immunohistochemical detection of the astrocytosis marker glial fibrillary acidic protein showed no differences between the SIDS and the matched control cases. These data indicate that there is no association of chronic hypoxia in the cerebellum with SIDS.
Collapse
|
22
|
Patural H, Flori S, Pichot V, Barthelemy JC, Roche F. [Autonomic regulation and bradycardia during the neonatal period]. Arch Pediatr 2013; 21:226-30. [PMID: 24290181 DOI: 10.1016/j.arcped.2013.10.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2012] [Revised: 08/28/2013] [Accepted: 10/14/2013] [Indexed: 12/16/2022]
Abstract
The high frequency of bradycardia observed during the neonatal period requires cardiac monitoring but also understanding its intrinsic mechanisms, including responsiveness of the autonomic nervous system (ANS). Heart rate variability and spontaneous baroreflex analysis can help understand the autonomic dysregulation of cardiorespiratory control, possibly responsible for sudden infant death. In clinical neonatology practice, neonatal bradycardia does not warrant continuation of monitoring if it remains isolated, asymptomatic, and short (<10 s), followed by a rapid cardiac acceleration indicating an adapted sympathetic response. Further evaluation of ANS responsiveness is possible for newborns including analyzing the complexity of the heart rate and respiratory variability. This allows better targeting children with high risk after discharge. The real-time evaluation of autonomic regulation could become a valuable tool in clinical practice.
Collapse
Affiliation(s)
- H Patural
- Réanimation néonatale et pédiatrique, centre hospitalier universitaire de Saint-Étienne, 42005 Saint-Étienne, France; EA SNA-Epis 4607, université Jean-Monnet, 42023 Saint-Étienne, France.
| | - S Flori
- EA SNA-Epis 4607, université Jean-Monnet, 42023 Saint-Étienne, France
| | - V Pichot
- EA SNA-Epis 4607, université Jean-Monnet, 42023 Saint-Étienne, France
| | - J-C Barthelemy
- EA SNA-Epis 4607, université Jean-Monnet, 42023 Saint-Étienne, France
| | - F Roche
- EA SNA-Epis 4607, université Jean-Monnet, 42023 Saint-Étienne, France
| |
Collapse
|
23
|
Intact numbers of cerebellar purkinje and granule cells in sudden infant death syndrome: a stereologic analysis and critical review of neuropathologic evidence. J Neuropathol Exp Neurol 2013; 72:861-70. [PMID: 23965745 DOI: 10.1097/nen.0b013e3182a31c31] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Despite much research during recent decades, the etiology and pathogenesis of sudden infant death syndrome (SIDS) remain unknown. Because of the role of the cerebellum in respiratory and cardiovascular control, it has been proposed that it plays an important role in the pathogenesis of SIDS. To date, 5 postmortem studies on the cerebellum of SIDS cases have yielded conflicting results. Using a rigorous design-based stereologic approach, we investigated postmortem cerebella from 9 SIDS patients who died between 2 and 10 months of age and from 9 age- and sex-matched control children. Neither the volumes of the cerebellar external granule cell layer, molecular layer, internal granule cell layer (including the Purkinje cell layer), and white matter nor the total numbers of Purkinje cells, granule cells in the internal granule cell layer, and the number of granule cells per Purkinje cell showed statistically significant differences between the SIDS cases and the controls. Based on these observations, we conclude that structural alterations in cerebellar development are not involved in the etiology and pathogenesis of SIDS.
Collapse
|
24
|
The development of cardiovascular and cerebral vascular control in preterm infants. Sleep Med Rev 2013; 18:299-310. [PMID: 23907095 DOI: 10.1016/j.smrv.2013.06.002] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2012] [Revised: 06/20/2013] [Accepted: 06/25/2013] [Indexed: 11/21/2022]
Abstract
Over the past three decades there has been a steady increase in the incidence of preterm birth. The worldwide rate of preterm birth is estimated to be 9.6% of all births, a total of almost 13 million births annually. Preterm birth is associated with a range of adverse cardiovascular and central nervous system outcomes, which may be attributed to altered development of these systems following preterm birth. Preterm birth has a considerable impact on cardiovascular parameters with preterm infants displaying higher heart rates and reduced blood pressure when compared to term born infants at matched ages. Furthermore, premature infants have altered autonomic control of cardiovascular parameters which manifests as abnormalities in heart rate variability and baroreflex mediated control of heart rate and blood pressure. As a result, systemic cardiovascular parameters can be unstable following preterm birth which may place stress on the neonatal brain. The brain of a preterm infant is particularly vulnerable to these fluctuations due to immature cerebral haemodynamics. Preterm infants, particularly those who are very preterm or unwell, display fluctuating pressure-passivity between systemic blood pressure and cerebral blood flow representing a considerably increased risk of cerebral haemorrhage or hypoxia. This is further compounded by immaturity of cerebral blood flow-metabolism coupling, which means increased metabolic demand cannot adequately be met by increased cerebral blood flow. It has been suggested that adverse long-term outcomes following preterm birth may occur as a result of exposure to physiological stress either in-utero or early in infancy.
Collapse
|
25
|
Golder V, Hepponstall M, Yiallourou SR, Odoi A, Horne RSC. Autonomic cardiovascular control in hypotensive critically ill preterm infants is impaired during the first days of life. Early Hum Dev 2013; 89:419-23. [PMID: 23313567 DOI: 10.1016/j.earlhumdev.2012.12.010] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Revised: 11/15/2012] [Accepted: 12/20/2012] [Indexed: 11/28/2022]
Abstract
BACKGROUND The first days after preterm birth are a critical period of cardiovascular instability, where hypotension is common. We assessed autonomic cardiovascular function by measuring heart rate variability (HRV), blood pressure variability (BPV) and baroreflex sensitivity (BRS) and hypothesised that these would be impaired in preterm infants born at younger gestational ages. In addition, we speculated that impaired cardiovascular control could be used as a marker of circulatory failure such as is manifest as hypotension. METHODS 23 preterm infants (11 M/12 F) born between 23 and 35 weeks (mean 27 ± 0.6 weeks) gestational age with indwelling arterial catheters were recruited. Infants were studied over the first 3 days of life with heart rate and blood pressure (BP) analysed beat to beat in the frequency domain in 2 minute epochs of artefact free data during active sleep. Data were compared with one way ANOVA. RESULTS Gestational age was correlated with all HRV indices but not BPV or BRS. 9 babies received inotropes. Gestational age between the inotrope group and the non-inotrope group was not different. BP and RR interval were lower in the inotrope group (40.7 ± 1.5 vs 47.1 ± 1.5 mmHg, p<0.05 and 395 ± 14 vs 426 ± 11 ms, p<0.08). BRS was also lower in the inotrope group (3.8 ± 0.9 vs 6.9 ± 1.6 ms/mmHg) as was LF/HF HRV (5.7 ± 1.3 vs 13.6 ± 2.8, p<0.05). CONCLUSIONS In the first 3 days after birth, infants receiving inotropes had significantly impaired cardiovascular control compared to those who did not receive treatment, indicating that these infants maybe predisposed to increased vulnerability to circulatory instability.
Collapse
Affiliation(s)
- Vera Golder
- The Ritchie Centre, Monash Institute of Medical Research, Monash University, Melbourne, Victoria 3168, Australia
| | | | | | | | | |
Collapse
|
26
|
The development of autonomic cardiovascular control is altered by preterm birth. Early Hum Dev 2013; 89:145-52. [PMID: 23058299 DOI: 10.1016/j.earlhumdev.2012.09.009] [Citation(s) in RCA: 93] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2012] [Revised: 09/11/2012] [Accepted: 09/14/2012] [Indexed: 11/23/2022]
Abstract
OBJECTIVES Autonomic dysfunction, either sympathetic or parasympathetic, may explain the increased incidence of Sudden Infant Death Syndrome (SIDS) among preterm infants, as well as their subsequent heightened risk of hypertension in adulthood. As little is known about the development of autonomic function in preterm infants, we contrasted autonomic cardiovascular control across the first 6months after term-corrected age (CA) in preterm and term infants. STUDY DESIGN Preterm (n=25) and age matched term infants (n=31) were studied at 2-4weeks, 2-3months and 5-6months CA using daytime polysomnography. Blood pressure and heart rate were measured during quiet (QS) and active (AS) sleep. Autonomic control was assessed using spectral indices of blood pressure and heart rate variability (BPV and HRV) in ranges of low frequency (LF, reflecting sympathetic+parasympathetic activity), high frequency (HF, respiratory-mediated changes+parasympathetic activity), and LF/HF ratio (sympatho-vagal balance). RESULTS In preterm infants, HF HRV increased, LF/HF HRV decreased and LF BPV decreased with age (p<0.05); these changes were most evident in AS. Compared to term infants, preterm infants in QS exhibited lower LF, HF and total HRV at 5-6months; higher HF BPV at all ages; and lower LF BPV at 2-4weeks (p<0.05). CONCLUSIONS With maturation, in preterm infants, parasympathetic modulation of the heart increases while sympathetic modulation of blood pressure decreases. Compared to term infants, preterm infants exhibit lesser parasympathetic modulation of the heart along with greater respiratory-mediated changes and lower sympathetic modulation of blood pressure. Impaired autonomic control in preterm infants may increase their risk of cardiovascular dysfunction later in life.
Collapse
|
27
|
Smith SL, Lux R, Haley S, Slater H, Beechy J, Moyer-Mileur LJ, Moyer-Mileur LJ. The effect of massage on heart rate variability in preterm infants. J Perinatol 2013; 33:59-64. [PMID: 22538325 PMCID: PMC3531576 DOI: 10.1038/jp.2012.47] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
OBJECTIVE To test the hypothesis that massage would improve autonomic nervous system (ANS) function as measured by heart rate variability (HRV) in preterm infants. STUDY DESIGN Medically stable, 29- to 32-week preterm infants (17 massage, 20 control) were enrolled in a masked, randomized longitudinal study. Licensed massage therapists provided the massage or control condition twice a day for 4 weeks. Weekly HRV, a measure of ANS development and function, was analyzed using SPSS generalized estimating equations. RESULTS Infant characteristics were similar between groups. HRV improved in massaged infants but not in the control infants (P<0.05). Massaged males had a greater improvement in HRV than females (P<0.05). HRV in massaged infants was on a trajectory comparable to term-born infants by study completion. CONCLUSION Massage-improved HRV in a homogeneous sample of hospitalized, medically stable, preterm male infants and may improve infant response to exogenous stressors. We speculate that massage improves ANS function in these infants.
Collapse
Affiliation(s)
- SL. Smith
- School of Nursing, University of Louisville, Louisville, KY, USA
| | - R. Lux
- Cardiovascular Research and Training Institute, University of Utah, Salt Lake City, UT, USA
| | - S. Haley
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - H. Slater
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - J. Beechy
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | - LJ. Moyer-Mileur
- Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, UT, USA
| | | |
Collapse
|