Introduction: Several studies demonstrated that high red cell distribution width (RDW) values are associ- ated with the severity of inflammatory processes. A recent study found that high RDW values signifcantly decrease after laparoscopic cholecystectomy (LC) in patients with acute cholecystitis. Therefore, we aimed to investigate, whether pre-operative RDW can predict the complexity of surgery and the risk of conversion from LC to open cholecystectomy (OC). Materials and Methods: Patients were divided into two groups according to the severity of inflammation with dense adhesions surrounding the gallbladder as Group I (n=140 patients); flms adhesions around the gallbladder that allow easy dissection, Group II (n=100 patients); severe adhesions encasing the gallbladder, including fbrosis, which makes dissection diffcult. Results: The mean age was 46.54±12.21 years. Eighty-fve patients were female and 155 patients were male. The mean percentage of pre-operative RDW was signifcantly higher in Group II patients when compared with Group I (15.26±2.0 vs. 12.53±0.84, p<0.001). Conversion cholecystectomy was performed signif- icantly higher in Group II patients (n=18, %18) than in Group I patients (n=3, 2.1%), (p<0.001). Conclusion: Results of the present study indicate that high RDW values are associated with inflammation and dense adhesions both in the gallbladder and surrounding tissue which make operation diffcult and increase rate of conversion to open surgery. Future studies consisting of large populations are needed to reach a defnite conclusion. [ABSTRACT FROM AUTHOR]