The effect of excessive ethanol ingestion on sleep in severe chronic obstructive pulmonary disease.

The effect of a moderately intoxicating dose of ethanol on sleep was evaluated in five patients with severe emphysematous chronic obstructive pulmonary disease (COPD) (mean FEV1 0.83 L, PaO2 75 mm Hg). Mean serum ethanol before sleep was 129 mg/dl. With alcohol, total sleep time per night decreased from a mean of 293 to 238 min. Relative sleep time per stage also changed; NREM time increased, and REM time decreased greater than 50%. Alcohol caused significant O2 desaturation; group mean sleep arterial oxygen saturation (SaO2) decreased from 90.6 to 87.7% with alcohol. Although the decrease in SaO2 was not uniform across all sleep stages, no individual sleep stage accounted for the desaturation. The fall in SaO2 with alcohol was not explained by increasing apneas or hypopneas. Mean heart rate increased significantly from 71.8 to 77.1 with alcohol, with premature ventricular contractions increasing in two subjects. Excessive alcohol ingestion in severe COPD alters total sleep time and stage distribution, decreases SaO2 without significant change in apneas, and increases heart rate. Prior to sleep, patients with severe COPD should strictly limit ingestion of alcohol.