Association of Overlapping Surgery With Patient Outcomes in a Large Series of Neurosurgical Cases.

Importance: Overlapping surgery (OS) is common. However, there is a dearth of evidence to support or refute the safety of this practice.

Objective: To determine whether OS is associated with worsened morbidity and mortality in a large series of neurosurgical cases.

Design, Setting, and Participants: A retrospective cohort study was completed for patients who underwent neurosurgical procedures at Emory University Hospital, a large academic referral hospital, between January 1, 2014, and December 31, 2015. Patients were operated on for pathologies across the spectrum of neurosurgical disorders. Propensity score weighting and logistic regression models were executed to compare outcomes for patients who received nonoverlapping surgery and OS. Investigators were blinded to study cohorts during data collection and analysis.

Main Outcomes and Measures: The primary outcome measures were 90-day postoperative mortality, morbidity, and functional status.

Results: In this cohort of 2275 patients who underwent neurosurgery, 1259 (55.3%) were female, and the mean (SD) age was 52.1 (16.4) years. A total of 972 surgeries (42.7%) were nonoverlapping while 1303 (57.3%) were overlapping. The distribution of American Society of Anesthesiologists score was similar between nonoverlapping surgery and OS cohorts. Median surgical times were significantly longer for patients in the OS cohort vs the nonoverlapping surgery cohort (in-room time, 219 vs 188 minutes; skin-to-skin time, 141 vs 113 minutes; both P < .001). Overlapping surgery was more frequently elective (93% vs 87%; P < .001). Regression analysis failed to demonstrate an association between OS and complications, such as mortality, morbidity, or worsened functional status. Measures of baseline severity of illness, such as admission to the intensive care unit and increased length of stay, were associated with mortality (intensive care unit: odds ratio [OR], 25.5; 95% CI, 6.22-104.67; length of stay: OR, 1.03; 95% CI, 1.00-1.05), morbidity (intensive care unit: OR, 1.85; 95% CI, 1.43-2.40; length of stay: OR, 1.06; 95% CI, 1.04-1.08), and unfavorable functional status (length of stay: OR, 1.03; 95% CI, 1.02-1.05).

Conclusions and Relevance: These data suggest that OS can be safely performed if appropriate precautions and patient selection are followed. Data such as these will help determine health care policy to maximize patient safety.