Clinical ScienceOutcomes of acute care surgical cases performed at night

•Comparison of day and night emergency surgical cases.•Variety of case types matched by complexity.•Night cases resulted in worse mortality.•No difference in complications between day and night cases.

BackgroundAcute care surgeons operate during the day and night. Time of day or night may impact the outcome because of surgeon and team fatigue, operative delays, or other unmeasured factors.MethodsWe performed matched retrospective cohort study of patients undergoing operative intervention at night by acute care surgeons over 16 months. Cases were matched on case complexity, age, and sex to daytime cases. Other confounders including comorbidities, presenting characteristics, complications, and mortality were abstracted. Outcomes differences between day and night cases were compared.ResultsNight cases (115) were matched 1:1 to daytime cases. Groups had similar degrees of comorbidity. Those operated at night had trends toward more hypotension and sepsis. After controlling for confounders using conditional logistic regression, surgical care at night was a potent predictor of mortality (odds ratio 30.02; 95% CI 2.33 to 387.40; P = .009) but had little impact on morbidity (odds ratio 1.34; 95% CI .77 to 2.36; P = .303).ConclusionsEmergency operations performed at night by acute care surgeons may have dissimilar outcomes compared with day cases.