Venous Thromboembolism Prophylaxis Adherence Rate in the Veterans Health Administration

Abstract

INTRODUCTION: Venous thromboembolism (VTE) represents a major source of preventable morbidity and mortality after cancer operation in the US. Previous research demonstrated variability in both inpatient and post-discharge VTE chemoprophylaxis prescribing, though it is unknown how these rates compare with performance in the Veterans Health Administration (VHA). The objective of this study is to determine VTE rate after major cancer operation as well as rate of chemoprophylaxis adherence within the VHA. METHODS: The Veterans Affairs Surgical Quality Improvement Program database (VASQIP) was used to identify patients without pre-existing bleeding disorder or anticoagulation usage who underwent a major abdominal or thoracic operation for cancer between January 1, 2015 and December 31, 2018. Rates of VTE events and VTE chemoprophylaxis adherence were determined. Multivariable logistic regression was used to determine odds of inpatient and outpatient chemoprophylaxis adherence. RESULTS: Overall, 13,377 patients met criteria for inclusion. All patients had a Caprini VTE Risk Index score greater than 5. The overall postoperative VTE rate was 1.7% (n = 227) with 49.4% occurring during inpatient hospitalization and 50.6% occurring while outpatient. Inpatient chemoprophylaxis was ordered for 80.3% of patients, yet only 8.6% of patients received outpatient chemoprophylaxis, with notable variation by specialty (Table). CONCLUSION: The overall VTE rate after major cancer operation within the VA is low. Inpatient chemoprophylaxis administration rate is high. Post-discharge VTE chemoprophylaxis prescribing is low, yet similar to other large, non-VA health systems. Specialty variation exists for chemoprophylaxis, and tailoring use based on risk may be justified. Table. - Specialty Variation in Venous Thromboembolism Prophylaxis after Major Operation Variable Inpatient Outpatient Surgical specialty a Percentage * OR (95% CI) Percentage * OR (95% CI) General surgery, n = 4,972 96.9% Reference 12.5% Reference Thoracic surgery, n = 1,509 95.6% 0.63 (0.41-0.98) 1.1% 0.07 (0.02-0.23) Urology, n = 6,846 64.9% 0.06 (0.04-0.08) 7.5% 0.51 (0.21-1.26) *All p < 0.001.OR, odds ratio.aExcluding 24 (0.18%) patients missing specialty data.