Learning curve and patient outcomes in gallstone surgery: a national register-based cohort study

There is no consensus on, or a defined minimum number of surgical laparoscopic cholecystectomies required to be considered an independent surgeon. The aim of the present study was to assess how surgical outcomes improve with surgical volume.

Data on laparoscopic cholecystectomies performed by surgical trainees and surgeons between 2006 and 2022 were retrieved from the Swedish national register for gallstone surgery (GallRiks). Surgeons who had not registered the number of procedures performed before first GallRiks entry were excluded. Comparisons regarding operation time and postoperatively observed complications were divided into strata of 50 performed procedures.

Between 2006 and 2022, 139,010 cholecystectomies were performed by surgeons (n = 1664) who had not yet performed 2000 procedures. The mean operation time decreased from 111 min (95% confidence interval (CI) 111-112 min) to 75 min (95% CI 73-77 min) after 800 completed procedures. During the first 50 procedures, the incidence of postoperatively observed complications was 4.7 and 7.0%, respectively, if the cholecystectomy was performed with or without a registered assistant (p = 0.007). The difference in the incidence of complications for assisted and unassisted procedures remained statistically significant up to 250 interventions performed.

Improvement in surgical outcomes and shorter operation time were observed over a long course of the expected learning curve. Although the presence of an assistant had a significant impact on the outcome during the initial phase of the learning curve, we do not know to what extent the assistant took part in the procedure. In GallRiks, only the presence of an assistant is registered, not what the assistant did during the procedure.