Anastomotic leak after low anterior resection: a spectrum of clinical entities.

IMPORTANCE Anastomotic leak is a potentially devastating complication of bowel surgery, yet a leak can refer to a range of clinical problems, with disparate treatment and outcomes. OBJECTIVES To qualitatively categorize the spectrum of anastomotic leaks that occur after low anterior resection for rectal cancer and to describe their effect on outcomes. DESIGN AND SETTING Retrospective review of a prospective database at an academic teaching hospital. PARTICIPANTS Two hundred ten patients with at least 1 year of follow-up data. INTERVENTION Low anterior resection for rectal cancer. MAIN OUTCOME MEASURES Anastomotic leak, associated treatment, and need for permanent stoma creation. RESULTS Of 198 study patients, 168 had no demonstrated anastomotic leak, free fluid, or abscess at any time after surgery. Of the remaining 30 patients, 17 had extravasation of contrast medium into the peritoneal cavity or the presacral space on a postoperative imaging study, some long after surgery. Six to 9 of these patients seemed to meet usual clinical criteria for anastomotic leak. Ten patients had only free or simple pelvic fluid collection without extravasation of contrast medium, and 3 patients had an abscess near the anastomotic site without extravasation of contrast medium. Male sex, diabetes mellitus, and radiation therapy (but not cigarette smoking) increased the risk for anastomotic leak. Anastomotic leak was correlated with the requirement for permanent stoma creation, while only free anastomotic leak was associated with an increased incidence of irregular bowel function. Notably, simple fluid without extravasation of contrast medium also correlated with irregular bowel function. CONCLUSIONS AND RELEVANCE A spectrum of clinical entities may be considered to represent an anastomotic leak after low anterior resection, with differing consequences. Presacral and free extravasation of contrast medium led to an increased need for permanent diversion, but even simple pelvic fluid collections were associated with irregular bowel function.