Risk factors for conversion of laparoscopic cholecystectomy to open surgery - A systematic literature review of 30 studies.

BACKGROUND: The study aims to evaluate the methodological quality of publications relating to predicting the need of conversion from laparoscopic to open cholecystectomy and to describe identified prognostic factors.

METHOD: Only English full-text articles with their own unique observations from more than 300 patients were included. Only data using multivariate analysis of risk factors were selected. Quality assessment criteria stratifying the risk of bias were constructed and applied.

RESULTS: The methodological quality of the studies were mostly heterogeneous. Most studies performed well in half of the quality criteria and considered similar risk factors, such as male gender and old age, as significant. Several studies developed prediction models for risk of conversion. Independent risk factors appeared to have additive effects.

CONCLUSION: A detailed critical review of studies of prediction models and risk stratification for conversion from laparoscopic to open cholecystectomy is presented. One study is identified of high quality with a potential to be used in clinical practice, and external validation of this model is recommended.