Oxygen can relieve dyspnoea in mildly and non-hypoxaemic people with COPD who would not otherwise qualify for home oxygen therapy. Given the significant heterogeneity among the included studies, clinicians should continue to evaluate patients on an individual basis until supporting data from ongoing, large randomised controlled trials are available.
Physical training with and without oxygen in patients with chronic obstructive pulmonary disease and exercise-induced hypoxaemia.
A randomized, controlled, single-blind study was performed on 20 patients with chronic obstructive pulmonary disease and exercise-induced hypoxaemia. Ten patients each were randomly assigned to one of two groups, one training with air and the other training with oxygen. There were no significant differences between the groups regarding values measured prior to the study. The patients trained 3 times per week for 30 minutes each time for a duration of 8 weeks. The training consisted of interval walking on a treadmill (intensity set according to Borg ratings) with either air or oxygen administered through a nasal cannula at a rate of 5 l/min. Training significantly improved the 6-minute walking distance by 20% and 14% in the air and oxygen group, respectively, when the patients were tested on air. In the same test the air group significantly decreased Borg ratings for perceived exertion. Borg ratings for dyspnoea and perceived exertion significantly decreased in the oxygen group when they were tested on oxygen. It was concluded that oxygen supplementation did not further improve the training effect, compared with training with air, in patients with chronic obstructive pulmonary disease and exercise-induced hypoxaemia.