Pre-Operative Score Development: Predicting Difficulty in Elective Laparoscopic Cholecystectomy

Objective: To develop and internally validate a pre-operative scoring system to predict difficulty in elective laparoscopic cholecystectomy (LC).Material and Methods: A retrospective diagnostic prediction study was conducted. Patients undergoing elective LC; from September 2016 to January 2023, at Hatyai Hospital in Southern Thailand were included. Patients were categorized by difficultly of LC according to the Nassar scale (grades 1-2 as non-difficult LC and grades 3-4 as difficult LC). Pre-operative data were compared between both groups; utilizing multivariable logistic regression. Internal validation was performed via the bootstrapping procedure.Results: In total, three hundred and eighteen patients were categorized into either; difficult LC 121 patients or non-difficult LC 197 patients. From this, 7 variables obtained from the multivariable logistic reduced model (male, cirrhosis, history of ERCP, ASA III, gallbladder wall ≥4 mm, dilated gallbladder, contracted gallbladder) were developed as a pre-operative score. The scoring (range: 0.0-16.6) was classified into 3 groups for clinical practicability. The positive predictive values (PPV) were 18.1 for low-risk, 38.0 for moderate-risk, and 76.0 for high-risk. Internal validation, via bootstrap technique, showed a C-statistic value of 0.76, and bootstrap shrinkage was 0.995. The prediction ability (AuROC) of the pre-operative score was 0.76.Conclusion: The developed of a pre-operative score had a good predictive performance, with fewer predictors for prediction difficulty of elective LC that can assist surgeons in surgical management selection.