Relationship between surgical volume and outcomes in elective and acute cholecystectomy: nationwide, observational study.

BACKGROUND: High surgical volumes are attributed to improved quality of care, especially for extensive procedures. However, it remains unknown whether high-volume surgeons and hospitals have better results in gallstone surgery. The aim of this study was to investigate whether operative volume affects outcomes in cholecystectomies.

METHODS: A registry-based cohort study was performed, based on the Swedish Registry of Gallstone Surgery. Cholecystectomies from 2006 to 2019 were included. Annual volumes for the surgeon and hospital were retrieved. All procedures were categorized into volume-based quartiles, with the highest group as reference. Low volume was defined as fewer than 20 operations per surgeon per year and fewer than 211 cholecystectomies per hospital per year. Differences in outcomes were analysed separately for elective and acute procedures.

RESULTS: The analysis included 154 934 cholecystectomies. Of these, 101 221 (65.3 per cent) were elective and 53 713 (34.7 per cent) were acute procedures. Surgeons with low volumes had longer operating times (P < 0.001) and higher conversion rates in elective (OR 1.35; P = 0.023) and acute (OR 2.41; P < 0.001) operations. Low-volume surgeons also caused more bile duct injuries (OR 1.41; P = 0.033) and surgical complications (OR 1.15; P = 0.033) in elective surgery, but the results were not statistically significant for acute procedures. Low-volume hospitals had more bile duct injuries in both elective (OR 1.75; P = 0.002) and acute (OR 1.96; P = 0.003) operations, and a higher mortality rate after acute surgery (OR 2.53; P = 0.007).

CONCLUSION: This study has demonstrated that operative volumes influence outcomes in cholecystectomy. The results indicate that gallstone surgery should be performed by procedure-dedicated surgeons at hospitals with high volumes of this type of benign surgery.