Evaluation of the use of an oxygen conservation device in long-term oxygen therapy.

An oxygen-conserving delivery system employing a flow reducing oxygen pendant (OP) cannula was evaluated during home use for oxygen savings, cost reduction, and patient acceptance. Twenty-one male outpatients receiving home oxygen from liquid systems by conventional nasal cannula (NC) were fitted with OP and followed for 1 month. Oxyhemoglobin saturations (SaO2) were successfully maintained with a threefold reduction in mean O2 flow rate from 1.45 to 0.46 L/min. Exercise testing demonstrated no change between the 2 systems in either degree of desaturation or duration of exercise. Because the same benefit was achieved at lower O2 flow with the OP, 14 patients were able to utilize their O2 for longer periods of time without refilling their portable liquid units. Liquid O2 use per patient was reduced from 200 pounds/month with NC to 135 pounds/month with OP. In 12 patients who reported full compliance during the study period; a net savings of $141/month/patient was realized. However, 9 of the 21 patients stopped using the OP before completing the study. Patient evaluations of the OP identified several factors leading to poor compliance, including bulkiness and/or poor fit (16 patients), ear discomfort (8 patients), nasal discomfort (6 patients), and required nasal breathing (6 patients). While significant savings were achieved with OP, problems with patient acceptance may limit its practicality, particularly in continuous use situations. The primary benefit of the OP may be in extending the range of portable oxygen systems.