Palliative Oxygen Offers No More Relief Than Intranasal Room Air
Simpler interventions might be preferable.
Intranasal oxygen is often used to relieve severe dyspnea in terminally ill patients, even when their PaO2 is not low enough to qualify for long-term oxygen therapy (i.e., below 55 mm Hg). But no clear evidence indicates that palliative oxygen has symptomatic benefits.
Investigators randomized 239 patients with life-limiting illness, refractory dyspnea, and PaO2 above 55 mm Hg to receive either oxygen or room air at 2L/minute via nasal cannula for at least 15 hours daily for 7 days. Beginning 2 days before the intervention started, patients were asked every morning and evening to rate their current dyspnea using a validated 10-point scale and to report secondary outcomes (e.g., quality of life).
No significant between-group differences were noted in reports of current dyspnea at any time. Both groups reported significant improvement during the course of the study (about 18% improvement in morning dyspnea and 9% improvement in evening dyspnea); the greatest decrease in both morning and evening dyspnea occurred within the first day of the intervention. Quality of life improved by about 12% in both groups.
Evidence shows that air movement across the face (e.g., from a hand-held fan) helps relieve dyspnea, and intranasal gas (whether oxygen or room air) might have a similar effect. Oxygen use is costly, logistically demanding, and risky in some patients (e.g., smokers, those with hypercapnia). Except for patients with true hypoxia, simpler interventions may be preferable for relieving dyspnea at the end of life.
Bruce Soloway, MD
Published in Journal Watch General Medicine September 14, 2010
Citation(s): Abernethy AP et al. Effect of palliative oxygen versus room air in relief of breathlessness in patients with refractory dyspnoea: A double-blind, randomised controlled trial. Lancet 2010 Sep 4; 376:784. (http://dx.doi.org/10.1016/S0140-6736(10)61115-4)