Timing and outcome of right- vs left-sided colonic anastomotic leaks: Is there a difference?

Anastomotic leaks (AL) contribute to postoperative mortality, prolonged hospitalization, and increased health care costs. While left-sided AL (LAL) are well described in the literature, there is a paucity of studies on outcomes and management of right-sided AL (RAL). This study aimed to compare the timing of RAL versus LAL, and the variable diagnosis, management and outcomes of RAL versus LAL. We hypothesized that the timing of RAL may be later compared to LAL and may result in worse overall outcomes.Patients who underwent curative intent surgery for neoplastic disease from January 1995 to December 2015 were included. Patients that underwent an anastomosis below the peritoneal reflection, neoadjuvant treatment, fecal diversion, previous colectomy/anastomosis, multiple anastomoses, and patients with inflammatory bowel disease or hereditary colorectal cancer syndromes were excluded. Patient demographics, neoplastic data, operative data, time to AL, methods utilized for diagnosis of AL, and management of AL were collected. The primary endpoint was timing of AL, and secondary endpoints were management and outcome based on RAL versus LAL. RAL and LAL were analyzed and compared using Chi-squared and categorical variables were expressed as number (percentage) and continuous variables expressed as median (interquartile range).A total of 2223 patients underwent oncologic resection for colonic neoplasia (1457 right sided and 766 left sided anastomoses). 67% of patients were male and median age was 69 years (range, 34-91). There were 48 total AL events (2.16%): 26 RAL (1.78%) and 22 LAL (2.87%). There was no statistical difference in leak rates between RAL and LAL and no difference in time to diagnosis or management (Table 1). RAL had significantly decreased operative time (p = 0.016), decreased intraoperative blood loss (p = 0.002), and increased diagnosis by CT/plain radiograph (p = 0.04). All patients that underwent surgery for leak had some form of fecal diversion performed. Morbidity and mortality were comparable between groups (p = 0.70; p = 1.0).This study found overall very low AL rates with comparable timing of RAL and LAL, and no difference in management or outcome of RAL vs. LAL. These findings are informative for patient and surgeon expectations before and after surgery and when AL is suspected.