(271) Operative Time Among Women Undergoing Hysterectomy in Two Hospital Systems: Predictors and The Relative Contributions of Patient/Procedure Factors Vs. Individual Surgeons

Publication Number: 945

Background: Operative time is an important multidimensional metric: it can be a marker of surgical case complexity; it is used to track surgeon skill and learning curves over time; it is an efficiency measure often tracked by hospital administrators; prolonged operative times have been associated with increased risks of postoperative complications.

Objectives: To examine predictors of operative time and the relative magnitudes of the contributions of patient/procedural factors and the surgeons themselves to the proportion of variation in operative time explained.

Methods: This was a retrospective study of de-identified electronic medical record data from two U.S. hospital systems (systems “A” and “B”) in the South and Midwest regions, comprising a total of 57 hospitals. Surgical records were selected for women undergoing hysterectomy between 2016 and 2021. Women from system A all received hysterectomy via the robotic surgical approach, whereas those from system B could have received any surgical approach. Analyzing data separately for systems A and B to examine the consistency of the results, multivariable linear regressions were used to examine the influence of the following factors on operative time (“cut to close” in minutes): patient demographics, body mass index, comorbidities, surgical indication, American Society of Anesthesiologists physical status classification (hospital system A only), surgical approach (system B only), elective vs. non-elective status, outpatient vs. inpatient setting, hospital regions, and individual surgeon fixed effects. The proportion of variation in operative time explained by patient/procedural factors vs. individual surgeon were quantified by examining model R-squared values (R2s).

Results: The study included 5,298 hysterectomies performed by 111 surgeons from 2019-2021 (system A) and 12,856 hysterectomies performed by 208 surgeons from 2016-2020 (system B). Mean (median) operative times were 113 (99) minutes in system A and 108 (97) in system B. When considering patient/procedural factors alone, R2s were 0.2432 for system A and 0.2027 for system B. When considering surgeon fixed effects alone, R2s were 0.4352 for system A and 0.4088 for system B. When considering both dimensions, R2s were 0.5452 for system A and 0.4924 for system B. In both analyses, BMI, surgical indication, elective vs. non-elective status, and outpatient vs. inpatient setting were significant predictors of operative time.

Conclusions: This analysis yielded remarkably consistent results across two separate hospital systems: operative time among women undergoing hysterectomy via a variety of surgical approaches was disproportionately driven by surgeon vs. patient/procedure factors.