Bruera, E., de Stoutz, N., Velasco-Leiva, A., Schoeller, T., & Hanson, J. (1993). Effects of oxygen on dyspnoea in hypoxaemic terminal-cancer patients. Lancet, 342(8862), 13–14.

The objective of the study is to assess oxygen therapy in patients with cancer.

Patients received two courses of oxygen at 5 L per minute and two courses of room air at 5 L per minute. Patients were randomized to either air or oxygen and then crossed over to the other treatment.

The study reported on a sample of 14 patients with hypoxemic dyspnea caused by advanced cancer previously treated with supplemental oxygen. Patients had normal cognitive function (MMSE score of at least 24/30) and hypoxemia (oxygen saturation less than 90% when patients breathed room air for more than five minutes). All were receiving oxygen via nasal cannula at 4 L per minute.

The study was a prospective, crossover, double-blind trial.

A baseline assessment occurred after 30 minutes of bed rest and a minimum of 5 minutes of stable oxygen saturation on room air. Dyspnea was assessed with VAS (0 = none to 100 = most). RR was measured for one minute twice; the results were averaged and assigned a score of 1–4 for RR. Patients made blind choices as to which treatment was most beneficial. Pulse oximetry evaluations also were recorded.

Oxygen saturation, respiratory rate and effort, and VAS were significantly better on oxygen (p < 0.0001). Researchers concluded that oxygen is beneficial to patients with hypoxia and dyspnea at rest.

• The study had a small sample size.
• The taste or smell of oxygen experienced by patients was not mentioned.
• The validity of the double-blind design is questioned.