Alcohol and hypoxia together during flights brought oxygen saturation levels down to as low as 80% in a recent study.
Researchers investigated the combined effects of moderate alcohol consumption and hypobaric hypoxia on sleep, oxygen saturation, and heart rate in long-haul flight passengers. The study, published in Thorax, involved 40 participants further divided into two groups: a control group in a normobaric sleep laboratory (n=23) and an inflight group (n=17) in a hypobaric altitude chamber simulating flight conditions at 2438 meters above sea level. Both groups were divided into subgroups: one consuming alcohol and the other not.
Each participant experienced two 4-hour sleep opportunities, with alcohol consumption (mean BAC 0.043 ± 0.003%) preceding one of the nights.
The findings revealed that combined alcohol and hypobaric conditions significantly reduced median blood oxygen saturation (SpO2) to 85.32% and increased median heart rate to 87.73 bpm during sleep. Non-alcohol conditions in normobaric environments showed higher SpO2 levels (median 95.88%) and lower heart rates (median 63.74 bpm). Combined exposure also resulted in prolonged hypoxia, with SpO2 levels below 90% for a median of 201.18 minutes compared to 0 minutes in normobaric conditions. Additionally, deep sleep duration was significantly reduced to a median of 46.50 minutes under the combined exposure.
In conclusion, the researchers stated their findings support the BTS Clinical Statement recommending avoiding alcohol 12 hours before and during flights for those with obstructive sleep apnea or obesity hypoventilation syndrome. They also called for increased public awareness through charities, campaigns, and airline health advice.
The authors have declared no competing interests.