Variability in Case Durations for Common Surgical Procedures

Published in: Anesthesia & Analgesia, Volume 126, Issue 6, pages 2017–2024 (June 2018). doi: 10.1213/ANE.0000000000002882

Posted on on January 20, 2021

by Laurent G. Glance, Richard P. Dutton, Changyong Feng, Yue Li, Stewart J. Lustik, Andrew W. Dick

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Under the Merit-based Incentive Payment System, physician payment will be adjusted using a composite performance score that has 4 components, one of which is resource use. The objective of this exploratory study is to quantify the facility-level variation in surgical case duration for common surgeries to examine the feasibility of using surgical case duration as a performance metric.


We used data from the National Anesthesia Clinical Outcomes Registry on 404,987 adult patients undergoing one of 6 general surgical or orthopedic procedures: laparoscopic appendectomy, laparoscopic cholecystectomy, laparoscopic cholecystectomy with intraoperative cholangiogram, knee arthroscopy, laminectomy, and total hip replacement. We constructed separate mixed-effects multivariable time-to-event models (survival analysis) for each of the 6 procedures to model surgical case duration.


We identified performance outliers, based on surgical case duration, using 2013 data and then quantified the gap between high- and low-performance outliers using 2014 data. After adjusting for patient risk, patients undergoing surgery at high-performance facilities were between 54% and 79% more likely to exit the operating room (OR) per unit time compared to average-performing facilities, depending on the procedure. For example, patients undergoing a laparoscopic appendectomy at high-performance facilities were 68% more likely to exit the OR per unit time (hazard ratio, 1.68; 95% CI, 1.40–2.02; P < .001) compared to average-performing facilities. Patients undergoing a laparoscopic appendectomy at low-performance facilities were 41% less likely to exit the OR per unit time (hazard ratio, 0.59; 95% CI, 0.47–0.74; P < .001) compared to average-performing facilities. The adjusted median surgical case duration for patients undergoing laparoscopic appendectomy was 69 minutes at high-performance centers and 92 minutes at low-performance centers. Similar results were obtained for the other procedures.


There was wide variation in surgery case duration for patients undergoing common general surgical and orthopedic surgeries. This variability in care delivery may represent an important opportunity to promote more efficient use of health care resources.

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