Enhancement of postoperative desaturation in heavy snorers.

The risk of postoperative decreases of arterial saturation in oxygen (SpO2) could be enhanced in patients with previous history of sleep-induced respiratory impairment. To test this hypothesis, patients scheduled for orthopedic surgery were classified preoperatively as heavy snorers, light snorers, and nonsnorers, according to their answers to a questionnaire. During the first postoperative night, the patients were breathing room air and both the arterial saturation and the tracheal sounds were monitored. Although the cumulated duration of snore was similar in the three groups, the number of desaturations (decrease in SpO2 > or = 4%) was more in the heavy snorers (14.9 +/- 27.9) than in the light snorers (0.1 +/- 0.3) and the nonsnorers (0.2 +/- 0.3) (P < 0.05). The percent duration of recording at SpO2 < 90% was longer in the heavy snorers (52.0% +/- 41.9% of the recording time) than in the two other groups: 9.3% +/- 12.4% (light snorers) and 17.5% +/- 21.8% (nonsnorers) (P < 0.05). Patients with a previous history of sleep-disordered breathing risked postoperative desaturation and could be detected preoperatively by the answers to certain questions.