Laparoscopic cholecystectomy: which predicting factors of conversion? Two Italian center's studies.

Background: Laparoscopic cholecystectomy represents the gold standard technique for the treatment of lithiasic gallbladder disease. Although it has many advantages, laparoscopic cholecystectomy is not risk-free and in special situations there is a need for conversion into an open procedure, in order to minimize postoperative complications and to complete the procedure safely. The aim of this study was to identify factors that can predict the conversion to open cholecystectomy.

Methods: We analyzed 1323 patients undergoing laparoscopic cholecystectomy over the last five years at St. Orsola University Hospital-Bologna and Umberto I University Hospital-Rome. Among these, 116 patients (8.7%) were converted into laparotomic cholecystectomy. Clinical, demographic, surgical and pathological data from these patients were included in a prospective database. A univariate analysis was performed followed by a multivariate logistic regression.

Results: On univariate analysis, the factors significantly correlated with conversion to open were the ASA score higher than 3 and the comorbidity, specifically cardiovascular disease, diabetes and chronic renal failure (P<0.001). Patients with a higher mean age had a higher risk of conversion to open (61.9±17.1 vs. 54.1±15.2, P<0.001). Previous abdominal surgery and previous episodes of cholecystitis and/or pancreatitis were not statistically significant factors for conversion. There were four deaths in the group of converted patients and two in the laparoscopic group (P<0.001). Operative morbility was higher in the conversion group (22% versus 8%, P<0.001). Multivariate analysis showed that the factors significantly correlated to conversion were: age <65 years old (P=0.031 OR: 1.6), ASA score 3-4 (P=0.013, OR:1.8), history of ERCP (P=0.16 OR:1.7), emergency procedure (P=0.011, OR:1.7); CRP higher than 0,5 (P<0.001, OR:3.3), acute cholecystitis (P<0.001, OR:1.4). Further multivariate analysis of morbidity, postoperative mortality and home discharge showed that conversion had a significant influence on overall post-operative complications (P=0.011, OR:2.01), while mortality (P=0.143) and discharge at home were less statistically influenced.

Conclusions: Our results show that most of the independent risk factors for conversion cannot be modified by delaying surgery. Many factors reported in the literature did not significantly impact conversion rates in our results.