Venous thromboembolism incidence among patients recommended for pharmacologic thromboembolism prophylaxis after cesarean delivery in selected guidelines.

BACKGROUND

Multiple guidelines regarding risk stratification for venous thromboembolism (VTE) incidence following cesarean delivery have been promulgated.

OBJECTIVE

To estimate the percentage of cesarean delivery patients for which pharmacologic VTE would be recommended and subsequent incidence of VTE, based on several guidelines.

PATIENTS/METHODS: This retrospective cohort study used data from the Nationwide Readmissions Database from October 2015 through December 2017. Diagnosis and procedure codes were used to identify patients undergoing cesarean delivery, incidence of VTE, and risk factors used to stratify risk in the existing guidelines. Time-to-event analysis was used to analyze data, stratified by risk categorization in 2011 American College of Obstetricians and Gynecologists (ACOG), 2012 American College of Chest Physicians (ACCP), 2015 Royal College of Obstetricians and Gynaecologists (RCOG), and 2018 American Society of Hematology (ASH) guidelines.

RESULTS/CONCLUSIONS: In a cohort of 1 235 149 cesarean deliveries, VTE incidence was 2.1 per 1000 deliveries at 330 days following delivery (95% confidence interval: 2.0-2.2). Proportions of patients that would be recommended for pharmacologic prophylaxis ranged from 0.2% in 2018 ASH guidelines to 73.4% in 2015 RCOG criteria. Among groups considered at elevated risk for VTE for which pharmacologic prophylaxis would be recommended, VTE incidence varied from 35.2 per 1000 deliveries based on 2018 ASH criteria to 2.5 per 1000 in 2015 RCOG criteria. In a large cohort of cesarean deliveries in the United States, application of different risk stratification guidelines identified widely different proportions at risk of VTE following delivery, with implications for being categorized as having elevated risk.