Development and validation of a clinical risk calculator for mortality after colectomy for fulminant Clostridium difficile colitis

BACKGROUND: Clostridium difficile colitis is an increasingly important cause of morbidity and mortality. Fulminant C. difficile colitis (FCDC) is a severe form of the colitis driven by a significant systemic inflammatory response, and managed with a total abdominal colectomy. Despite surgery, postoperative mortality rates remain high. The aim of this study was to develop a bedside calculator to predict the risk of 30-day postoperative mortality for patients with FCDC. METHODS: After institutional review board approval, the American College of Surgeons National Surgical Quality Improvement Program database (2005-2015) was used to include adult patients who underwent emergency surgery for FCDC. A priori preoperative predictors of mortality were selected from the literature: age, immunosuppression, preoperative shock, intubation, and laboratory values. The predictive accuracy of different logistic regression models was measured by calculating the area under the receiver-operating characteristic curve. A cohort of 124 patients from Quebec was used to validate the developed mortality calculator. RESULTS: A total of 557 patients met the inclusion criteria, and the overall mortality was 44%. After developing the calculator, no statistically significant differences were found in comparison with the American College of Surgeons National Surgical Quality Improvement Program probability of mortality available in the database (area under the receiver operating curve, 75.61 vs. 75.14; p = 0.79). External validation with the cohort of patients from Quebec showed an area under the curve of 74.0% (95% confidence interval, 65.0-82.9). CONCLUSION: A clinically applicable calculator using preoperative variables to predict postoperative mortality for patients with FCDC was developed and externally validated. This calculator may help guide preoperative decision making. (Copyright (C) 2019 Wolters Kluwer Health, Inc. All fights reserved.)