Many surgeons tend to overuse proximal fecal diversion in the setting of colonic surgery. The decision to proximally divert an anastomosis should be made with careful consideration of the risks and benefits of proximal diversion. Proximal diversion does not decrease the rate of anastomotic leak, but it does decrease the severity of leaks. Anastomotic height for low pelvic anastomoses, hemodynamic instability, steroid use, male sex, obesity, malnutrition, smoking, and alcohol abuse increase the rate of anastomotic leak. Biologics, most immunosuppressive agents, unprepped colons, and radiation for rectal cancer do not contribute to increased rates of anastomotic leak. Proximal fecal diversion creates additional potential morbidity, higher rates of readmission, and need for a subsequent hospitalization and operation for reversal. Additionally, diverted patients have higher rates of anastomotic stricture and delayed recognition of chronic leaks. These downsides to diversion must be weighed with a patient's perceived ability to handle the physiologic stress and consequences of a severe leak if reoperation is required. When trying to determine which patients can handle a leak, the modified frailty index can help to objectively determine a patient's risk for increased rate of morbidity and failure to rescue in the event of a leak. While proximal diversion is still warranted in many cases, we find that certain clinical scenarios often lead to overuse of proximal diversion. The old surgical adage "If you are considering diverting, you should probably do it" should be tempered by an understanding of the risk and benefits of diversion.
