322 Projected impact of guideline adoption on venous thromboembolism incidence following cesarean delivery in the US

Abstract

Because venous thromboembolism (VTE) is a common cause of maternal morbidity and mortality in the United States, a variety of different guidelines have been proposed for its prevention. These guidelines have been largely constructed by expert consensus, and the implications of their adoption for rates of receipt of VTE prophylactic therapy and potential rates of VTE are unknown. In this study, we simulate the potential implications of guideline adoption for post-cesarean VTE prevetion. We used administrative data from the 2015-2017 National Readmissions Database to identify cesarean delivery, and rates of subsequent VTE, stratified by risk factors that would lead to different prophylactic strategies based on several national guidelines. We then used additional input parameters from the published literature to construct a hybrid decision tree / Markov model to project the implications of guideline adoption on VTE rates for the first 6 weeks following cesarean section (Figure 2a). From 1.3 million hospitalizations in the NRD dataset, we identified the incidence of VTE and risk categories corresponding to various potential guidelines (Figure 1). Based on prior data, we calibrated the rate of VTE following cesarean delivery as 4.3 per 1/1,000 deliveries. Use of either the 2011 American College of Obstetricians and Gynecologists or 2018 American Society for Hematology guidelines would avert a relatively small proportion of VTE cases, albeit with little use of LWMH (Figure 2b). In comparison, the 2012 American College of Chest Physicians and the 2015 Royal College of Royal College of Obstetricians and Gynaecologists guidelines would avert a larger proportion of cases, at the cost of much higher rates of LWMH utilization. Adoption of different guidelines would have notably varying implications for clinical practice, and potential for alteration of the national rate of VTE following cesarean delivery. Further research is needed to evaluate the performance of these guidelines in practice, and to quantify the costs, adverse effects, and cost-effectiveness of these approaches.View Large Image Figure ViewerDownload Hi-res image Download (PPT)