What Does Venous Thromboembolism Mean in the National Surgical Quality Improvement Program?

Background: Venous thromboembolism (VTE) affects an estimated 350,000 to 600,000 individuals and causes approximately 100,000 deaths annually in the United States. Postoperative VTE is a core measure reported by The American College of Surgeons' National Surgical Quality Improvement Program (NSQIP). The objective of this research was to assess the validity of VTE events reported by NSQIP. Materials and methods: This is a retrospective analysis using NSQIP data from January 2006 through December 2018 and the electronic health record system data from five adult hospitals in the Johns Hopkins Health System. We included patients aged 18 years and older with a VTE event identified in our NSQIP data set. The main outcome measure was the proportion of valid VTE events, defined as concordant between the NSQIP data set and medical chart review for clinical documentation. Results: Of 474 patients identified in our NSQIP database with a VTE, 26 (5.5%) did not meet the strict NSQIP definition of VTE. Nine had a preoperative history of DVT and no new postoperative event, seven had a negative workup for VTE, six had a peripheral arterial thrombus, two did not receive or refused therapy, one had an aortic thrombus, and one had a venous thrombosis in a surgical flap. Conclusions: We identified a considerable number of surgical patients misclassified as having a VTE in NSQIP, when did not truly. This highlights the need to improve definition specificity and standardize processes involved in data extraction, validation, and reporting to provide unbiased data for use in quality improvement.