Document Detail

Effects of oxygen supplementation on cerebral oxygenation during exercise in chronic obstructive pulmonary disease patients not entitled to long-term oxygen therapy.
MedLine Citation:
PMID:  22152079     Owner:  NLM     Status:  In-Data-Review    
Background:  The rate of change (Δ) in cerebral oxygenation (COx) during exercise is influenced by blood flow and arterial O(2) content (CaO(2) ). It is currently unclear whether ΔCOx would (i) be impaired during exercise in patients with chronic obstructive pulmonary disease (COPD) who do not fulfil the current criteria for long-term O(2) therapy but present with exercise-induced hypoxaemia and (ii) improve with hyperoxia (FIO(2)  = 0·4) in this specific sub-population. Methods:  A total of 20 non-hypercapnic men (FEV(1)  = 47·2 ± 11·5% pred) underwent incremental cycle ergometer exercise tests under normoxia and hyperoxia with ΔCOx (fold-changes from unloaded exercise in O(2) Hb) being determined by near-infrared spectroscopy. Pulse oximetry assessed oxyhaemoglobin saturation (SpO(2) ), and impedance cardiography estimated changes in cardiac output (ΔQT). Results:  Peak work rate and ΔCOx in normoxia were lower in eight O(2) 'desaturators' compared with 12 'non-desaturators' (P<0·05). Area under ΔCOx during sub-maximal exercise was closely related to SpO(2) decrements in 'desaturators' (r = 0·92, P<0·01). These patients showed the largest improvement in peak exercise capacity with hyperoxia (P<0·05). Despite a trend to lower sub-maximal ΔQT and mean arterial pressure with active intervention, ΔCOx was significantly improved only in this group (0·57 ± 0·20 versus 2·09 ± 0·42 for 'non-desaturators' and 'desaturators', respectively; P<0·05). Conclusions:  ΔCOx was impaired in non-hypoxaemic patients with COPD who desaturated during exercise. Hyperoxic breathing was able to correct for these abnormalities, an effect related to enhanced CaO(2) rather than improved central haemodynamics. This indicates that O(2) supplementation ameliorates exercise COx in patients with COPD who are not currently entitled to ambulatory O(2) therapy.
Mayron F Oliveira; Miguel K Rodrigues; Erika Treptow; Thúlio M Cunha; Eloara M V Ferreira; J Alberto Neder
Related Documents :
22195389 - Validity of field expedient devices to assess core temperature during exercise in the c...
9738129 - Effects of split exercise sessions on excess postexercise oxygen consumption and restin...
9041069 - Reliability of perceived exertion during graded exercise testing in apparently healthy ...
19713649 - The borg scale as an important tool of self-monitoring and self-regulation of exercise ...
16627049 - Autonomic nervous system interaction with the cardiovascular system during exercise.
24080099 - Progenitor cell release plus exercise to improve functional performance in peripheral a...
10524349 - Hepatic branched-chain alpha-keto acid dehydrogenase complex in female rats: activation...
15032999 - Where to q in pep.
3455549 - The acute haemodynamic effects of intravenous verapamil in patients with chronic obstru...
Publication Detail:
Type:  Journal Article     Date:  2011-10-03
Journal Detail:
Title:  Clinical physiology and functional imaging     Volume:  32     ISSN:  1475-097X     ISO Abbreviation:  Clin Physiol Funct Imaging     Publication Date:  2012 Jan 
Date Detail:
Created Date:  2011-12-13     Completed Date:  -     Revised Date:  -    
Medline Journal Info:
Nlm Unique ID:  101137604     Medline TA:  Clin Physiol Funct Imaging     Country:  England    
Other Details:
Languages:  eng     Pagination:  52-8     Citation Subset:  IM    
Copyright Information:
© 2011 The Authors. Clinical Physiology and Functional Imaging © 2011 Scandinavian Society of Clinical Physiology and Nuclear Medicine.
Pulmonary Function and Clinical Exercise Physiology Unit, Division of Respiratory Diseases, Department of Medicine, Federal University of Sao Paulo (UNIFESP), Sao Paulo, Brazil.
Export Citation:
APA/MLA Format     Download EndNote     Download BibTex
MeSH Terms

From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine

Previous Document:  Effect of different types of lower body resistance training on arterial compliance and calf blood fl...
Next Document:  Cerebrovascular responses to cold pressor test during static exercise in humans.