Long-term home oxygen therapy.

Oxygen therapy improves mortality and morbidity in hypoxemic patients with COPD. For best results, oxygen should be administered continuously. The general guidelines that qualify a patient for long-term home oxygen therapy are rather explicit, although there are some gray areas, such as increasing exercise performance in normoxemic COPD patients and the treatment of dyspnea in certain patients. The physiologic goals of oxygen therapy are to reverse or prevent tissue hypoxia under the various conditions of life. Patients often experience a fall in oxygen saturation during REM sleep and during exercise. Thus, the oxygen prescription should specify the oxygen setting during wakeful rest, sleep, and exertion. Pulmonary rehabilitation is the definitive long-term management for patients with chronic lung diseases by building endurance, strength, and coping skills. Patients undergoing pulmonary rehabilitation are taught to become active and mobile. The rehabilitation programs have a special role in helping patients to accept and properly administer their own oxygen therapy. Oxygen therapy should be based on mobility and portability. Improvements in the weight and bulk of oxygen containers and the introduction of oxygen-conserving devices have rendered oxygen systems more portable and less costly. The prescription initiates a clinical triad relationship between the patient, physician, and home oxygen vendor. Prescribing home oxygen is now more time-consuming, and the prescription process requires the careful attention of the physician. The prescription must include patient data, the diagnostic reasons for oxygen, the blood gases, the type of system, and the liter-flow for the various living conditions such as rest, sleep, and exertion. Reimbursement for oxygen via Medicare and other carriers will depend upon the physiologic data as well as the successful completion of a rather complex form. Oxygen therapy should be monitored by regular arterial blood gases or pulse oximetry where appropriate. Patients should have a blood gas sample taken upon any change of condition or adjustment of the oxygen flow setting. Successful oxygen therapy should be physician directed, based on a solid understanding of the physiologic processes involved.