LAUSR

BACKGROUND Since most anastomoses after left-sided colorectal resections are performed with a circular stapler, any technological change in stapling devices may influence the incidence of anastomotic adverse events. The aim of the present study was to analyze the effect of a three-rows circular stapler on anastomotic leakage and related morbidity after left-sided colorectal resections. MATERIALS AND METHODS A circular stapled anastomosis was performed in 4,255 (50.9%) out of 8,359 patients enrolled in two prospective multicenter studies in Italy, and, after exclusion criteria to reduce heterogeneity, 2,799 (65.8%) cases were retrospectively analyzed through a 1:1 propensity score-matching model including 20 covariates relative to patient characteristics, to surgery and to perioperative management. Two well balanced groups of 425 patients each were obtained: group (A) - true population of interest, anastomosis performed with a 3-rows circular stapler; group (B), - control population, anastomosis performed with a 2-rows circular stapler. The target of inferences was the average treatment effect in the treated (ATT). The primary endpoints were overall and major anastomotic leakage, and overall anastomotic bleeding; the secondary endpoints were overall and major morbidity, and mortality rates. The results of multiple logistic regression analyses for the outcomes, including the 20 covariates selected for matching, were presented as odds ratios (OR) and 95% confidence intervals (95%CI). RESULTS Group A vs. group B showed a significantly lower risk of overall anastomotic leakage [2.1 vs. 6.1%; OR 0.33; 95%CI 0.15-0.73; P=.006], major anastomotic leakage [2.1 vs. 5.2%; OR 0.39; 95%CI 0.17-0.87; P=.022], and major morbidity [3.5 vs. 6.6% events; OR 0.47; 95%CI 0.24-0.91; P=.026]. CONCLUSION The use of 3-rows circular staplers independently reduced the risk of anastomotic leakage and related morbidity after left-sided colorectal resection. Twenty-five patients were required to avoid one leakage.