PB1522 - Facility variation in patients qualifying for venous thromboembolism prophylaxis after Cesarean delivery in the United States

Background: Venous thromboembolism (VTE) is a major contributor to maternal morbidity and mortality in higher income countries. Concomitantly, there are efforts to measure and standardize the quality of pregnancy care across healthcare facilities. However, variation in the distribution of VTE risk among different facilities may lead to differences in both process (e.g., receipt of prophylactic anticoagulation) and outcome metrics (e.g., VTE incidence).

Aims: To identify any facility variation in the rate of VTE risk factors among patients undergoing cesarean delivery in the United States.

Methods: Retrospective cohort study using the 2019 National Readmissions Database. Cesarean deliveries and risk factors for VTE were identified using International Classification of Disease, Tenth Edition, Clinical Modification Diagnosis and Procedure Coding System codes. Included facilities had at least 50 identified cesarean deliveries. We applied a previously developed algorithm for identifying patients qualifying for postpartum thromboprophylaxis. We compared the percentage of patients qualifying for thromboprophylaxis by facility between the 2018 American Society of Hematology (ASH), 2012 American College of Chest Physicians (ACCP), and 2015 Royal College of Obstetrics and Gynaecology (RCOG) criteria.

Results: There were 535,500 cesarean deliveries among 1,122 facilities. VTE prophylaxis criteria were met for 0.3% of patients per ASH, 18.2% per ACCP, and 76.1% per RCOG. Within facilities, the percentage of patients meeting criteria ranged from 0-3.3% for ASH, 0.4%-62.6% for ACCP, and 21.5%-96.5% for RCOG (Figure 1). Patients delivering at metropolitan teaching hospitals were more likely to meet criteria when compared to other hospital types (Figure 2; p < 0.001 for all comparisons).

Conclusion(s): There is substantial variation in the distribution of VTE risk factors among patients delivering at hospitals in the United States. This finding suggests caution is needed when developing quality metrics comparing percentage of patients receiving prophylaxis and need for risk adjustment when comparing hospital VTE rates.