High-Risk Ileocolic Anastomoses for Crohn's Disease: When Is Diversion Indicated?

Patients with Crohn's disease undergoing ileocolectomy and primary anastomosis are often at increased risk of anastomotic leak. We aimed to determine whether diverting ileostomy was protective against anastomotic leak after ileocolic resection for Crohn's disease using a large international registry. We analysed the National Surgical Quality Improvement Program Colectomy Module from 2012 to 2016. Multivariable logistic regression analysis and propensity-score matching were used to identify independent risk factors for leak, and to test the hypothesis that diverting ileostomy was protective against anastomotic leakage. A total of 4172 [92%] patients underwent primary anastomosis, and 365 [8%] underwent anastomosis plus ileostomy. The leak rates in the two groups were 4.5% and 2.7%, [p = 0.12], respectively. Multivariate analysis indicated ileostomy omission, emergency surgery, smoking, inpatient status, wound classification 3 or 4, weight loss, steroid use, and prolonged operative time were independently associated with leak. Patients with 0-6 risk factors had leak rates of 1.6%, 2.7%, 4.3%, 6.7%, 8.8%, 11.5%, and 14.3% [p ≤ 0.001], respectively. Following propensity-score matching, ileostomy reduced the risk of leak rate by 55% [p = 0.005]. Patients with primary anastomosis who leaked most frequently required reoperation [57.8%], but anastomosis plus ileostomy patients who leaked most frequently were managed by percutaneous drainage [70%], p = 0.04. After ileocolic resection for Crohn's disease, anastomotic leak may be predicted by simple addition of risk factors. We found that diverting ileostomy mitigated against leak, reducing both the leak rate and the likelihood of unplanned reoperations. Faecal diversion should be considered when ≥3 risk factors are present.