Redefining Conversion in Laparoscopic Colectomy and Its Influence on Outcomes: Analysis of 418 Cases from a Single Institution

Background The reported rates of conversion in laparoscopic colectomy are varied. The incidence of conversion is not, however, well defined. The aim of the present study is to redefine conversion and to analyze differences in outcome. Methods Treatment parameters of a total of 418 consecutive patients who underwent laparoscopic colonic resection from 2005 to 2007 were analyzed. Treatment was classified as laparoscopic colonic resection, laparoscopy-assisted colonic resection (lap-assisted), and laparoscopic conversion. Results There were significant differences in median operating time between laparoscopic colonic resection, lap-assisted, and laparoscopic conversion (125 min, 160 min, and 140 min; p = 0.0001); median hospital length of stay was significantly different (laparoscopic, 5.0 days, versus lap-assisted, 6.0 days, versus laparoscopic conversion, 6.5 days; p = 0.0001); and median incision length was also noted to vary significantly (laparoscopic, 5.0 cm, lap-assisted, 8.0 cm, and conversion, 12.0 cm; p = 0.00001). Multivariate analysis reveals that older age (Odds Ratio [OR] = 1.07, 95% Confidence Interval [CI] = 1.02-1.12), higher Body Mass Index ([BMI], OR = 1.15, 95% CI = 1.03-1.29), and pT stage were significant factors affecting conversion. Disease-free survival for cancers was not influenced by conversion p = 0.653). The overall complication rate was 16.7% and was significanly increased in lap-assisted cases and in conversion cases (26% versus 13%; p = 0.003). Conclusions A consistent definition for conversion in laparoscopic colonic resection is required. Our proposed definitions may provide a solution. The definition of lap-assisted as a separate entity serves as a bridge between laparoscopy and full conversion. Risk factors of age, BMI, and advanced tumor stage are conversion predictors and are associated with increased hospital stay and postoperative morbidity.