Preoperative predictors of conversion in elective laparoscopic cholecystectomy

Abstract

Introduction: Laparoscopic Cholecystectomy, the gold standard for management of gall stone disease, has a conversion rate of 1.6%-20% at different centers. We audited our elective laparoscopic cholecystectomies, to enable preoperative prediction of the probability of conversion. Method: Retrospective audit of all laparoscopic cholecystectomies from Jan 2013 to March 2017 was done. The cases that required conversion to open cholecystectomy were evaluated for pre- and intraoperative factors responsible for conversion and statistically analyzed using SPSS version 23 [IBM, USA]. Results: 764 patients (mean age 42.9 years) were taken up for laparoscopic cholecystectomies of which 33(4.31%) were converted to open cholecystectomy. The operative factors responsible for conversion were: (1) the presence of dense pericholecystic adhesions (P<0.001), (2) frozen Callot's triangle (P=0.013), (3) unclear anatomy (P=0.002) and iatrogenic injury to CBD (n=2), or bowel (duodenum and colon n=1). Pre-operative factors associated with conversion included age>60y (P=0.032), male sex (P=0.17), history of fever (P<0.032), prior ERCP (P=0.012) and anatomy complicated by cholecystoenteric fistula or Mirrizi's syndrome (P<0.001) Sonographic findings of contracted GB, thick walled GB, and stone impacted at neck of gallbladder were found to have high predictive value for conversion (P<0.001). Conclusion: Male sex, Age>60years, history of fever with pain, Mirrizi's syndrome, prior ERCP, ultrasound finding of a contracted gallbladder, thick walled gallbladder, and/or stone impaction at neck of gallbladder, significantly predispose to conversion at laparoscopic cholecystectomy. These preoperative factors translate intra-operatively into an unclear anatomy (suggesting that recurrence of inflammation causes increased fibrosis and unclear anatomy at Calot's) predisposing to a higher conversion rate.