Acute cholecystitis: predictive clinico-radiological assessment for conversion of laparoscopic cholecystectomy.

ABSTRACT

BACKGROUND: Previous studies evaluating predictive factors for the conversion from laparoscopic to open cholecystectomy have reported conflicting conclusions. PURPOSE: To create a risk assessment model to predict the conversion from laparoscopic to open cholecystectomy in patients with acute calculous cholecystitis. MATERIAL AND METHODS: A retrospective review of patients with acute calculous cholecystitis with available preoperative contrast-enhanced computed tomography (CT) findings who underwent laparoscopic cholecystectomy was performed. Forty-four parameters-including demographics, clinical history, laboratory data, and CT findings-were analyzed. RESULTS: Among the included 581 patients, conversion occurred in 113 (19%) cases. Multivariate analysis identified obesity (odd ratio [OR] 2.58, P = 0.04), history of abdominal surgery (OR 1.78, P = 0.03), and prolonged prothrombin time (OR 1.98, P = 0.03) as predictors of conversion. In preoperative CT findings, the absence of gallbladder wall enhancement (OR 3.15, P = 0.03), presence of a gallstone in the gallbladder infundibulum (OR 2.11, P = 0.04), and inflammation of the hepatic pedicle (OR 1.71, P = 0.04) were associated with conversion. Inter-observer agreement for CT study interpretation was very good (range 0.81-1.00). A model was created to calculate the risk for conversion, with an area under the receiver operating characteristic curve of 0.87. The risk for conversion, estimated based on the number of factors identified, was in the range of 5.3% (with one factor) to 86.4% (with six factors). CONCLUSION: Obesity, history of abdominal surgery, prolonged prothrombin time, absence of gallbladder wall enhancement, presence of a gallstone in the gallbladder infundibulum, and inflammation of the hepatic pedicle are associated with conversion of laparoscopic to open cholecystectomy.