An intraoperative transfer of care from one anesthesia provider to another, or handover, may result in information loss and contribute to adverse patient outcomes. In 2019 the authors undertook a quality improvement effort to increase the use of a structured intraoperative handover tool incorporated in the electronic medical record. The authors hypothesized that intraoperative handovers of anesthesia care would be associated with adverse patient outcomes, and that increased use of a structured tool would attenuate this effect.


This study included adult patients undergoing noncardiac surgery of at least 1 h duration performed during the period 2016 to 2021. Cases with a handover were identified if either there was a change of attending anesthesiologist or change of nurse anesthetist or resident for more than 35 min. The primary outcome was the occurrence of a composite of postoperative mortality and major postoperative morbidity. The effect of the intervention was analyzed by examining the quarterly change in odds ratio for the primary outcome for cases with and without a handover.


A total of 121,077 cases, 40.4% of which had a handover, were included. After weighting, the composite outcome was statistically associated with handovers (3,517 of 48,986 [7.2%] in handover cases vs. 4,470 of 72,091 [6.2%] in nonhandover cases; odds ratio, 1.08; 95% CI, 1.04 to 1.12). Time series analysis showed a marked increase in usage of the structured tool after the initial intervention. The odds ratio for the composite outcome showed a significant decrease over time after the initial intervention (t = –3.97; P < 0.001), with the slope of the odds ratio versus time curve decreasing from 0.002 (95% CI, 0.001 to 0.004; P = 0.018) to –0.011 (95% CI, –0.01 to –0.018; P < 0.001).


Intraoperative handovers are significantly associated with adverse outcomes even after controlling for multiple confounding variables. Use of a structured handover tool during anesthesia care may attenuate the adverse effect.

Editor’s Perspective
What We Already Know about This Topic
  • Handovers—the transitioning of care from one provider to another—may be associated with increased risk of adverse outcomes in anesthetic care.
What This Article Tells Us That Is New
  • In this retrospective cohort study in more than 120,000 cases, the authors found that intraoperative handovers significantly increased the risk of adverse events during noncardiac surgery. However, the use of a structured handover tool that was developed by the authors during a quality improvement initiative significantly reduced the risk during intraoperative handovers.