Cardio-respiratory, oxidative stress and acute mountain sickness responses to normobaric and hypobaric hypoxia in prematurely born adults.

Details

Ressource 1Request a copy Sous embargo indéterminé.
State: Public
Version: author
License: Not specified
Serval ID
serval:BIB_628B0602FCB5
Type
Article: article from journal or magazin.
Collection
Publications
Institution
Title
Cardio-respiratory, oxidative stress and acute mountain sickness responses to normobaric and hypobaric hypoxia in prematurely born adults.
Journal
European journal of applied physiology
Author(s)
Debevec T., Pialoux V., Poussel M., Willis S.J., Martin A., Osredkar D., Millet G.P.
ISSN
1439-6327 (Electronic)
ISSN-L
1439-6319
Publication state
Published
Issued date
06/2020
Peer-reviewed
Oui
Volume
120
Number
6
Pages
1341-1355
Language
english
Notes
Publication types: Journal Article
Publication Status: ppublish
Abstract
We compared the effects of hypobaric and normobaric hypoxia on select cardio-respiratory responses, oxidative stress and acute mountain sickness (AMS) severity in prematurely born individuals, known to exhibit blunted hypoxic ventilatory response.
Sixteen prematurely born but otherwise healthy males underwent two 8-h hypoxic exposures under: (1) hypobaric hypoxic [HH; terrestrial altitude 3840 m; P <sub>i</sub> O <sub>2</sub> :90.2 (0.5) mmHg; BP: 478 (2) mmHg] and (2) normobaric hypoxic [NH; P <sub>i</sub> O <sub>2</sub> :90.6 (0.9) mmHg; F <sub>i</sub> O <sub>2</sub> :0.142 (0.001)] condition. Resting values of capillary oxyhemoglobin saturation (SpO <sub>2</sub> ), heart rate (HR) and blood pressure were measured before and every 2 h during the exposures. Ventilatory responses and middle cerebral artery blood flow velocity (MCAv) were assessed at rest and during submaximal cycling before and at 4 and 8 h. Plasmatic levels of selected oxidative stress and antioxidant markers and AMS symptoms were also determined at these time points.
HH resulted in significantly lower resting (P = 0.010) and exercise (P = 0.004) SpO <sub>2</sub> as compared to NH with no significant differences in the ventilatory parameters, HR or blood pressure. No significant differences between conditions were found in resting or exercising MCAv and measured oxidative stress markers. Significantly lower values of ferric-reducing antioxidant power (P = 0.037) were observed during HH as opposed to NH. AMS severity was higher at 8 h compared to baseline (P = 0.002) with no significant differences between conditions.
These data suggest that, in prematurely born adults, 8-h exposure to hypobaric, as opposed to normobaric hypoxia, provokes greater reductions in systemic oxygenation and antioxidant capacity. Further studies investigating prolonged hypobaric exposures in this population are warranted.
NCT02780908 (ClinicalTrials.gov).
Keywords
Acute mountain sickness, Cardio-respiratory responses, High altitude, Hypoxemia, Oxidative stress, Prematurity
Pubmed
Web of science
Create date
25/04/2020 21:51
Last modification date
17/02/2021 7:27
Usage data