Evaluation of an oxygen concentrator in patients with COPD

The value of a new oxygen concentrator was investigated in 20 patients with COPD. The oxygenating ability of the device was compared to that of piped-in oxygen at flows of 1, 2, 4, 6, 8, and 10 l/min by measuring arterial blood gases after 14 min of breathing through a nasal cannula. For flows up to 4 l/min, the concentrator produced increases in PaO2 that were comparable to the increases resulting from piped-in oxygen. At higher flows, the PaO2 achieved by each flow of 6-10 l/min was significantly less when using the concentrator as compared to piped-in oxygen. The device was reliable, easy to use, and well accepted. It was concluded that the concentrator provides a useful alternative to piped-in oxygen or cylinders of oxygen for patients requiring flows of up to 4 l/min.