Predicting the risk of readmission from dehydration after ileostomy formation: The dehydration readmission after ileostomy prediction score

BACKGROUND: All-cause readmission rates in patients undergoing ileostomy formation are as high as 20% to 30%. Dehydration is a leading cause. No predictive model for dehydration readmission has been described. OBJECTIVE: The purpose of this study was to develop and validate the Dehydration Readmission After Ileostomy Prediction scoring system to predict the risk of readmission for dehydration after ileostomy formation. DESIGN: Patients who underwent ileostomy formation were identified using the American College of Surgeons National Surgical Quality Improvement Program data set (2012–2015). Predictors for dehydration were identified using multivariable logistic regression analysis and translated into a point scoring system based on corresponding β-coefficients using 2012–2014 data (derivation). Model discrimination was assessed with receiver operating characteristic curves using 2015 data (validation). SETTINGS: This study used the American College of Surgeons National Surgical Quality Improvement Program. PATIENTS: A total of 8064 (derivation) and 3467 patients (validation) were included from the American College of Surgeons National Surgical Quality Improvement Program. MAIN OUTCOME MEASURES: Dehydration readmission within 30 days of operation was measured. RESULTS: A total of 8064 patients were in the derivation sample, with 2.9% (20.1% overall) readmitted for dehydration. Twenty-five variables were queried, and 7 predictors were identified with points assigned: ASA class III (4 points), female sex (5 points), IPAA (4 points), age ≥65 years (5 points), shortened length of stay (5 points), ASA class I to II with IBD (7 points), and hypertension (9 points). A 39-point, 5-tier risk category scoring system was developed. The model performed well in derivation (area under curve = 0.71) and validation samples (area under curve = 0.74) and passed the Hosmer–Lemeshow goodness-of-fit test. LIMITATIONS: Limitations of this study pertained to those of the American College of Surgeons National Surgical Quality Improvement Program, including a lack of generalizability, lack of ileostomy-specific variables, and inability to capture multiple readmission International Classification of Diseases, 9^th/10^th edition, codes. CONCLUSIONS: The Dehydration Readmission After Ileostomy Prediction score is a validated scoring system that identifies patients at risk for dehydration readmission after ileostomy formation. It is a specific approach to optimize patient factors, implement interventions, and prevent readmissions. See Video Abstract at http://links.lww.com/DCR/A746.