Context: Few data exist on the relationships between experienced physicians' work hours and sleep, and patient safety.
Objective: To determine if sleep opportunities for attending surgeons and obstetricians/gynecologists are associated with the risk of complications.
Design, setting, and patients: Matched retrospective cohort study of procedures performed from January 1999 through June 2008 by attending physicians (86 surgeons and 134 obstetricians/gynecologists) who had been in the hospital performing another procedure involving adult patients for at least part of the preceding night (12 am-6 am, postnighttime procedures). Sleep opportunity was calculated as the time between end of the overnight procedure and start of the first procedure the following day. Matched control procedures included as many as 5 procedures of the same type performed by the same physician on days without preceding overnight procedures. Complications were identified and classified by a blinded 3-step process that included administrative screening, medical record reviews, and clinician ratings.
Main outcome measures: Rates of complications in postnighttime procedures as compared with controls; rates of complications in postnighttime procedures among physicians with more than 6-hour sleep opportunities vs those with sleep opportunities of 6 hours or less.
Results: A total of 919 surgical and 957 obstetrical postnighttime procedures were matched with 3552 and 3945 control procedures, respectively. Complications occurred in 101 postnighttime procedures (5.4%) and 365 control procedures (4.9%) (odds ratio, 1.09; 95% confidence interval [CI], 0.84-1.41). Complications occurred in 82 of 1317 postnighttime procedures with sleep opportunities of 6 hours or less (6.2%) vs 19 of 559 postnighttime procedures with sleep opportunities of more than 6 hours (3.4%) (odds ratio, 1.72; 95% CI, 1.02-2.89). Postnighttime procedures completed after working more than 12 hours (n = 958) compared with 12 hours or less (n = 918) had nonsignificantly higher complication rates (6.5% vs 4.3%; odds ratio, 1.47; 95% CI, 0.96-2.27).
Conclusion: Overall, procedures performed the day after attending physicians worked overnight were not associated with significantly increased complication rates, although there was an increased rate of complications among postnighttime surgical procedures performed by physicians with sleep opportunities of less than 6 hours.