Effect of Normobaric Hypoxia on Exercise Performance in Pulmonary Hypertension: Randomized Trial.
altitude
chronic thromboembolic pulmonary hypertension
echocardiography
exercise testing
pulmonary arterial hypertension
Journal
Chest
ISSN: 1931-3543
Titre abrégé: Chest
Pays: United States
ID NLM: 0231335
Informations de publication
Date de publication:
02 2021
02 2021
Historique:
received:
15
05
2020
revised:
24
08
2020
accepted:
04
09
2020
pubmed:
13
9
2020
medline:
14
9
2021
entrez:
12
9
2020
Statut:
ppublish
Résumé
Many patients with pulmonary arterial or chronic thromboembolic pulmonary hypertension (PH) wish to travel to altitude or by airplane, but their risk of hypoxia-related adverse health effects is insufficiently explored. How does hypoxia, compared with normoxia, affect constant work-rate exercise test (CWRET) time in patients with PH, and which physiologic mechanisms are involved? Stable patients with PH with resting Pao Twenty-eight patients (13 women) were included: median (quartiles) age, 66 (54; 74) years; mean pulmonary artery pressure, 41 (29; 49) mm Hg; and pulmonary vascular resistance, 5.4 (4; 8) Wood units. Under normoxia and hypoxia, CWRET times were 16.9 (8.0; 30.0) and 6.7 (5.5; 27.3) min, respectively, with a median difference (95% CI) of -0.7 (-3.1 to 0.0) min corresponding to -7 (-32 to 0.0)% (P = .006). At end-exercise in normoxia and hypoxia, respectively, median values and differences in corresponding variables were as follows: Pao In patients with PH, short-time exposure to hypoxia was well tolerated but reduced CWRET time compared with normoxia in association with hypoxemia, lactacidemia, and hypocapnia. Because pulmonary hemodynamics and dyspnea at end-exercise remained unaltered, the hypoxia-induced exercise limitation may be due to a reduced oxygen delivery causing peripheral tissue hypoxia, augmented lactic acid loading and hyperventilation. ClinicalTrials.gov; No.: NCT03592927; URL: www.clinicaltrials.gov.
Sections du résumé
BACKGROUND
Many patients with pulmonary arterial or chronic thromboembolic pulmonary hypertension (PH) wish to travel to altitude or by airplane, but their risk of hypoxia-related adverse health effects is insufficiently explored.
RESEARCH QUESTION
How does hypoxia, compared with normoxia, affect constant work-rate exercise test (CWRET) time in patients with PH, and which physiologic mechanisms are involved?
STUDY DESIGN AND METHODS
Stable patients with PH with resting Pao
RESULTS
Twenty-eight patients (13 women) were included: median (quartiles) age, 66 (54; 74) years; mean pulmonary artery pressure, 41 (29; 49) mm Hg; and pulmonary vascular resistance, 5.4 (4; 8) Wood units. Under normoxia and hypoxia, CWRET times were 16.9 (8.0; 30.0) and 6.7 (5.5; 27.3) min, respectively, with a median difference (95% CI) of -0.7 (-3.1 to 0.0) min corresponding to -7 (-32 to 0.0)% (P = .006). At end-exercise in normoxia and hypoxia, respectively, median values and differences in corresponding variables were as follows: Pao
INTERPRETATION
In patients with PH, short-time exposure to hypoxia was well tolerated but reduced CWRET time compared with normoxia in association with hypoxemia, lactacidemia, and hypocapnia. Because pulmonary hemodynamics and dyspnea at end-exercise remained unaltered, the hypoxia-induced exercise limitation may be due to a reduced oxygen delivery causing peripheral tissue hypoxia, augmented lactic acid loading and hyperventilation.
TRIAL REGISTRY
ClinicalTrials.gov; No.: NCT03592927; URL: www.clinicaltrials.gov.
Identifiants
pubmed: 32918899
pii: S0012-3692(20)34370-1
doi: 10.1016/j.chest.2020.09.004
pii:
doi:
Banques de données
ClinicalTrials.gov
['NCT03592927']
Types de publication
Journal Article
Randomized Controlled Trial
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
757-771Commentaires et corrections
Type : CommentIn
Informations de copyright
Copyright © 2020 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.