Creation and validation of a condition-specific venous thromboembolism risk assessment tool for ventral hernia repair

BackgroundWe used the database of the American College of Surgeons National Surgical Quality Improvement Program to (1) identify risk factors for 30-day venous thromboembolism (VTE) after ventral hernia repair (VHR) and (2) to create and validate a condition-specific assessment tool for the risk of VTE.MethodsOpen and laparoscopic VHR patients in the American College of Surgeons National Surgical Quality Improvement Program were identified using Current Procedural Terminology code. The occurrence of VTE, including deep-venous thrombosis (DVT) or pulmonary embolus, within 30 days postoperatively was the primary outcome. Regression-based analysis and subsequent bootstrap analysis created a weighted VTE risk assessment model (RAM) for ventral hernia repair. The weighted RAM was used to risk-stratify patients for both 30-day VTE risk and 30-day risk for medical and surgical complications.ResultsData for 113,873 hernia repair patients were obtained; 30-day deep-venous thrombosis, pulmonary embolus, and VTE rates were 0.59%, 0.43%, and 0.92%, respectively. The average time to VTE was 10.8 days. A 14-factor, weighted RAM was created. The weighted risk score identified a 25-fold variability (from 0.20 to 4.97%) in VTE risk among the overall VHR population. Although created to risk-stratify for VTE, the risk score also risk-stratified for 30-day medical and surgical complications, inpatient duration of stay, and 30-day mortality.ConclusionThe 30-day VTE risk after VHR is 0.92%, but a 25-fold variability in VTE risk exists among the overall hernia population. We demonstrate that a weighted VTE RAM quantifies VTE risk among the population undergoing ventral hernia repair, and that VTE risk score can also be used to risk-stratify for 30-day medical and surgical complications as well as mortality.