Importance of conversion for results obtained with laparoscopic colorectal surgery

The need for a conversion is a problem inherent in laparoscopic surgery. The present study points up the significance of conversion for the results obtained with laparoscopic colorectal surgery and identifies the risk factors that establish the need for conversion.

The study took the form of a multicentric, prospective, observational study within the Laparoscopic Colorectal Surgery Study Group. A total of 33 institutions in Germany, Austria, and Switzerland participated. The study period was 3.5 years. Cases were documented with the aid of a standardized questionnaire.

Within the framework of the Laparoscopic Colorectal Surgery Study Group, a total of 1,658 patients were recruited to a multicenter study over a period of three and one-half years (from August 1, 1995 to February 1, 1999). The observed conversion rate was 5.2 percent (n = 86). The patients requiring a conversion were significantly heavier (body mass index, 26.5 vs. 24.9) than those undergoing pure laparoscopy. Resections of the rectum were associated with a higher risk for conversion (20.9 vs. 13 percent). Intraoperative complications occurred significantly more frequently in the conversion group (27.9 vs. 3.8 percent). The duration of the operation was significantly increased after conversion in a considerable proportion of the procedures performed. Postoperative morbidity (47.7 vs. 26.1 percent), mortality (3.5 vs. 1.5 percent), recovery time, and postoperative hospital stay were all negatively influenced by conversion, in part significantly. Institutions with experience of more than 100 laparoscopic colorectal procedures proved to have a significantly lower conversion rate than those with experience of fewer than 100 such interventions (4.3 vs. 6.9 percent).

Although, of itself, conversion is not considered to be a complication of laparoscopic surgery, it is true that the postoperative course after conversion is associated with appreciably poorer results in terms of morbidity, mortality, convalescence, blood transfusion requirement, and postoperative hospital stay. The importance of experience in laparoscopic surgery can be demonstrated on the basis of the conversion rates. Careful patient selection oriented to the experience of the surgeon is required if we are to keep the conversion, morbidity, and mortality rates of laparoscopic colorectal procedures as low as possible.