Factors Associated with Clinically Significant Anastomotic Leakage after Large Bowel Resection: Multivariate Analysis of 707 Patients

The aim of this study was to determine by univariate and multivariate analyses the factors associated with clinically significant anastomotic leakage (AL) after large bowel resection. From 1990 to 1997 a series of 707 patients underwent colonic or rectal resection (without a stoma). Patients were divided into two groups: those with clinical anastomotic leakage (group 1) and those without it (group 2). AL occurred in 43 of 707 patients (6%). The overall mortality was 2.2% and was significantly higher in patients with AL than in those without: 5 of 43 (12%) versus 11 of 664 (1.6%), p <0.001. Univariate analysis showed 15 variables associated with the risk of AL: previous abdominal or pelvic irradiation (p = 0.02), American Society of Anesthesiologists (ASA) score > 2 (p = 0.04), leukocytosis (p = 0.02), renal failure (p = 0.03), steroid treatment (p = 0.01), duration of operation (p = 0.001), intraoperative septic conditions (p = 0.006), total colectomy (p = 0.009), transverse colectomy (p = 0.02), difficulties encountered during anastomosis (p = 0.001), ileorectal anastomosis (p = 0.02), colocolic anastomosis (p = 0.01), abdominal drainage (p = 0.05), and blood transfusion intraoperatively (p = 0.006) and postoperatively (p = 0.001). Multivariate analysis showed that only preoperative leukocytosis (p = 0.04), intraoperative septic conditions (p = 0.001), difficulties encountered during anastomosis (p = 0.007), colocolic anastomosis (p = 0.004), and postoperative blood transfusion (p = 0.0007) were independent factors associated with AL. The risk of AL increased from a range of 12% to 30% if one risk factor was present, to 38% with two factors, to 50% with three factors. After colorectal resection and intraperitoneal anastomosis, a temporary protective stoma is proposed in selected patients with high risk factors for AL, as observed in our study.