Background: Long-term oxygen therapy (LTOT) is an established treatment for patients with chronic hypoxemia. Its scientific basis is derived mainly from two trials from the early 1980s that showed a survival advantage for patients with chronic obstructive pulmonary disease (COPD) treated with LTOT. Robust data are not available for other diseases associated with hypoxemia.
Methods: This review is based on pertinent publications retrieved by a selective search in PubMed.
Results: The use of LTOT for 15 to 16 hours per day (or, better, 24 hours per day) is recommended in current guidelines for patients with chronic hypoxemia (PaO2 ≤ 55 mm Hg) because this treatment was found to be associated with a lower mortality rate compared to no LTOT (33% vs. 55%, p <0.05) based on data from the early 1980s. In the short term, oxygen administration to a hypoxemic patient can improve oxygen saturation by nine percentage points and improve physical performance to a clinically relevant extent (6-minute walking test: + 37 m, p <0.001). The available data do not support the use of LTOT for normoxemic patients. LTOT should only be administered for strict indications, in accordance with the guidelines, and only in a form suitable for the individual patient. Skin burns can occur as a side effect of LTOT because of contact explosions with any type of fire.
Conclusion: The acquisition of further robust data would be desirable, particularly with respect to patient-relevant outcome parameters including quality of life, performance status, and mortality. Moreover, the German guidelines on oxygen therapy need to be updated.