Oxygen therapy and delivery in obstructive pulmonary disease.

The guidelines for O2 therapy in acute decompensation of COPD and even the indications for short-term use of O2 during periods of increased requirements in stable COPD are fairly clear-cut. With regard to continuous O2 therapy in hypoxemic patients with stable COPD, most would agree that in patients with cor pulmonale treatment with low concentrations of O2 for periods of more than 12 hours per day will result in improved pulmonary hemodynamics, mental function, polycythemia, and perhaps exercise tolerance. In similar patients without cor pulmonale the potential benefit of continuous O2 is unknown. Many other serious questions remain. The optimum duration of chronic O2 therapy must be clarified. More data are needed to determine the effect of continuous O2 therapy on mortality rate at both sea level and high altitude. It is not known whether O2 therapy has any prophylactic value in those patients with COPD who have not developed severe pulmonary hypertension. The potential value of O2 therapy in exercise rehabilitation programs needs further study. Finally, lightweight, longer-lasting, and less-expensive O2 delivery systems must be sought.