Are oxygen-conserving devices effective for correcting exercise hypoxemia?

Respir Care. 2013 Oct;58(10):1606-13. doi: 10.4187/respcare.02260. Epub 2013 Mar 19.


Background: Correction of exercise hypoxemia in advanced lung diseases is crucial and often challenging. However, oxygen-conserving devices have been introduced in the market with limited evidence of effectiveness. In the present study the efficacy of 2 oxygen-conserving devices, a pulse demand oxygen delivery (DOD) system and pendant reservoir cannula (PRC), were evaluated in subjects with COPD and interstitial lung disease (ILD).

Methods: A cross-sectional, crossover study included 28 COPD and 31 ILD subjects with oxygen desaturation on the 6-min walk test (average S(pO2) < 88%). Each subject underwent 3 walk tests with DOD, PRC, and continuous oxygen flow by standard nasal cannula (CFNC), in random order, taking average S(pO2) ≥ 90% as the resaturation criterion.

Results: Exercise desaturation was corrected in 79%, 79%, and 86% of COPD subjects with CFNC, DOD, and PRC, respectively, and in 77%, 61%, and 81% of ILD subjects with CFNC, DOD, and PRC, respectively. When compared to CFNC, the oxygen-conserving devices showed similar efficacy, except a lower performance for the DOD in the ILD subjects (P = .01).

Conclusions: Although these oxygen-conserving devices corrected exercise hypoxemia in most COPD and ILD subjects, correction was not achieved in about 20% of the severe COPD subjects, regardless of the device, and in nearly 40% of the ILD subjects with the DOD device. These findings underscore that individualized adjustment of oxygen flow is needed for optimal correction of exercise hypoxemia, especially with a DOD in an ILD patient. ( NCT01086891).

Keywords: COPD; conservers; exercise test; interstitial lung disease; oxygen inhalation therapy; technology assessment.

Publication types

  • Multicenter Study
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Aged
  • Cross-Over Studies
  • Cross-Sectional Studies
  • Equipment Design
  • Exercise / physiology*
  • Exercise Test / adverse effects
  • Female
  • Follow-Up Studies
  • Humans
  • Hypoxia / etiology
  • Hypoxia / metabolism
  • Hypoxia / prevention & control*
  • Lung Diseases / therapy*
  • Male
  • Oxygen / pharmacology*
  • Oxygen Consumption
  • Oxygen Inhalation Therapy / instrumentation*
  • Retrospective Studies
  • Treatment Outcome


  • Oxygen

Associated data