Long-term oxygen therapy.

Long-term oxygen therapy (LTOT) has been shown to reduce pulmonary hypertension and improve survival in patients with chronic obstructive pulmonary disease and resting hypoxemia (reduced arterial partial pressure of oxygen ≤55 mmHg). However, the benefit of its use for chronic pulmonary diseases other than chronic obstructive pulmonary disease as well as for nonpulmonary conditions is debatable. Its role in patients with mild hypoxemia (reduced arterial partial pressure of oxygen >55 mmHg at rest) is presently being investigated in the LOTT. A meta-analysis of four controlled trials reporting the role of LTOT in patients with either nocturnal desaturation or daytime moderate hypoxemia found no difference in survival between patients on LTOT than those without. Advances in oxygen delivery and conservation devices have made domiciliary oxygen therapy more practical and popular for patients. There still remain concerns with the actual compliance of therapy among the needy patients.