Venous thromboembolism in benign esophageal surgery patients: potential cost effectiveness of Caprini risk stratification

Abstract
The Caprini risk assessment model (RAM) stratifies surgical patients for prescription of post-discharge extended heparin prophylaxis to reduce post-operative venous thromboembolism (VTE) events. The average cost for treatment of a VTE event is $15,123. The 30-day post-operative VTE rate after benign esophageal procedures is < 0.8% per the Society of Thoracic Surgeons database. We hypothesized that the financial cost of selective extended prophylaxis in patients undergoing surgery for benign esophageal disease would exceed the cost of treating these rare events and therefore use of risk stratification for extended prophylaxis would not be beneficial. All patients undergoing operations for benign esophageal pathology from July 2014 to May 2019 were reviewed. Patients designated as moderate or high risk for VTE were prescribed a 10- or 30-day post-operative course of extended prophylaxis with low-molecular weight heparin (LMWH). VTE and adverse bleeding events were recorded for the 60-day post-operative period. The cost of LMWH was provided by the institution pharmacy. Records from 154 patients were eligible for review. Caprini RAM was used for all patients with the following distribution of risk categories: low = 64.9% (100/154); moderate = 31.8% (49/154); and high = 3.2% (5/154). The average cost of extended prophylaxis at discharge for the moderate-risk group was $121.23, while the high-risk group was $446.46. There were no 60-day VTE or adverse bleeding events recorded. The majority of patients undergoing surgical therapy were at low risk of post-operative VTE event, with only 35% requiring extended VTE prophylaxis at time of discharge. When compared with the average cost of treatment for a VTE event, the cost of extended prophylaxis per patient in moderate or high-risk groups is substantially lower. In the era of cost-containment, risk stratification and extended prophylaxis may reduce healthcare costs and warrant future investigations.