Oxygen therapy for hypercapnic patients with chronic obstructive pulmonary disease and acute respiratory failure: a...

To investigate the effect of oxygen therapy on outcome and on symptomatic hypercapnia.

Randomized, controlled, single-blind study.

Multidisciplinary intensive care unit of a university teaching hospital.

Patients admitted with a clinical diagnosis of an acute exacerbation of chronic obstructive pulmonary disease and a PaO2 <6.6 kPa (50 mm Hg) and PaCO2 >6.6 kPa (50 mm Hg) on air.

Patients received oxygen therapy titrated to increase arterial oxygen tension to >6.6 kPa (50 mm Hg) or >9 kPa (70 mm Hg). Patients in the low-oxygen tension group also received doxapram if they developed an acidosis with pH <7.2, whereas those in the high-oxygen tension group received doxapram if they developed symptomatic acidosis. Bronchodilator, steroid, and antibiotic therapy was standardized.

Two patients in the low-oxygen tension group (n = 17) required mechanical ventilation and another one died. No patients in the high-oxygen group (n = 17) had a poor outcome, but this difference was not significant. No patient in either group became comatose or developed an acute cardiac arrhythmia.

Traditional teaching related to oxygen therapy for hypercapnic patients with an acute exacerbation of chronic obstructive pulmonary disease may be incorrect. A large randomized, controlled study is required to confirm this impression.