A randomised, double blind cross-over trial of the effect of oxygen on dyspnoea in patients with advanced cancer

Dyspnoea is a common symptomatic problem in palliative care. Despite this, there is uncertainty regarding the role of oxygen to treat the symptom in this patient group. This paper presents the results of a randomised, double blind cross-over trial seeking to examine the effect of oxygen versus air on the relief of dyspnoea in patients with advanced cancer. Following the administration of air and oxygen via nasal prongs, 51 patients rated dyspnoea and indicated preferences for the blinded treatments. On average, patients improved symptomatically with both air and oxygen, and there were no significant differences between the treatments. The subgroup of 17 hypoxic patients also did not demonstrate a significant difference between air and oxygen, despite having improved oxygen saturations when administered oxygen. The experience of dyspnoea is a complex, multi-factorial phenomenon with oxygen tension not correlating with the subjective experience. The administration of air or oxygen via nasal prongs on average confers improvement of the symptom.