The Association of Intraoperative Anesthesia Handovers of Anesthesia Care With Adverse Postoperative Outcomes: A Retrospective Multicentric Cohort Study.

BACKGROUND: Intraoperative anesthesia handovers are common in academic practice due to shift-based staffing, duty-hour limits, and the demands of prolonged procedures, and occur among both attending anesthesiologists and supervised providers. Although handovers may serve as important safety checkpoints, they also represent vulnerable periods during which loss of critical information can occur. This study evaluated whether intraoperative handovers among attending anesthesiologists are associated with prolonged hospital length of stay (HLOS) and increased risk of unplanned 30-day readmission. METHODS: We conducted a retrospective multicenter cohort study of noncardiac, nonambulatory adult patients who underwent general anesthesia between 2007 and 2021 at two academic healthcare networks in the Bronx, New York, and Boston, Massachusetts. The exposure was intraoperative handover of anesthesia care among attending anesthesiologists. The primary outcome was HLOS. The secondary outcome was unplanned 30-day readmission. We used multivariate linear regression models (continuous outcomes) and modified Poisson regression with robust error variances (binary outcomes) to assess the association between exposure and outcomes. We conducted an interaction analysis to investigate the effect modification of the primary and secondary association by case complexity. Additionally, we evaluated handovers among certified registered nurse anesthetists (CRNAs) and/or residents in exploratory analyses, as well as the time of anesthesia handover. RESULTS: A total of 145,383 patients were included, of whom 16,984 of 145,383 (11.7%) underwent an intraoperative handover of anesthesia care. Handovers were associated with a prolonged HLOS (median [interquartile range {IQR}]: 4.0 [2.0-7.0] vs 3.0 [2.0-5.0] days; adjusted model estimate [MEadj], 1.02 [95% confidence interval {CI}, 1.02-1.03]; P < .001) and higher hospital readmission rate compared to of no-handover cases; (14.0% vs 12.3%, respectively, adjusted risk ratios [RRadj], 1.06 [95% CI, 1.02-1.11], P = .003). The association between handover and HLOS was more pronounced in patients undergoing major surgery (MEadj, 1.04 [95% CI, 1.03-1.05], P < .001) compared to nonmajor surgeries (MEadj, 1.01 [95% CI, 1.00-1.02], P = .023, P-for-interaction = .001), was significant among CRNAs and/or residents (MEadj, 1.03 [95% CI, 1.02-1.05], P < .001) and when the handover occurred late in the day or at night compared to earlier in the day (late versus early: MEadj, 1.08 [95% CI, 1.05-1.11], P < .001; night versus early: MEadj 1.12 [95% CI, 1.08-1.16]; P < .001). CONCLUSIONS: Intraoperative handover of anesthesia care is associated with a small but measurable increase in HLOS and increased 30-day unplanned readmission, particularly in major surgical cases. Handovers among supervised providers may contribute to prolonged hospitalization.