Optimizing anticoagulation for hospitalized children: A single-institution pediatric anticoagulation stewardship experience

Abstract Introduction: Children are at increased risk for preventable anticoagulation-related adverse events due to variable pharmacokinetics, which require frequent dosing adjustments and regimen modifications. Anticoagulation stewardship programs (ASPs) aim to reduce medication-related errors and enhance patient safety. This single-institution quality improvement (QI) initiative aimed to improve adherence to institutional anticoagulation protocols and optimize dosing and monitoring strategies in hospitalized pediatric patients. Methods: A physician-and pharmacist-led pediatric ASP was implemented at Holtz Children's Hospital for inpatients under 22 years of age receiving anticoagulation. QI interventions were introduced in two phases: Phase 1 (1/2024-6/2024) focused on multidisciplinary protocol development, creation of a HIPAA-compliant automated dashboard to identify eligible patients, and a pilot program of weekly stewardship rounds with prospective audit and feedback on protocol adherance. Phase 2, beginning in October 2024, added targeted staff education and continuation of weekly rounds. Stewardship recommendations on anticoagulant dosing and monitoring were provided weekly to primary teams. An interim analysis from 1/2024-7/2025 was conducted. Data collected included demographics, anticoagulant type, dose, indication, co-morbidities, and if applicable, new thrombosis events (characteristics, treatment, and outcomes including bleeding events, length of stay (LOS), and follow-up). Recommendations were categorized by type and acceptance. Metrics were compared between phases using two-sided p-values (p<0.05 was considered significant). Results: A total of 537 anticoagulation-related encounters across 205 patient admissions were reviewed. Indications included inpatient thromboprophylaxis (36.7%, n=197), acute thrombosis (34.1%, n=183), secondary/long-term thromboprophylaxis (26.6%, n=143), and extracorporeal membrane oxygenation (ECMO) (2.1%, n=11). Commonly used anticoagulants were low molecular weight heparin (LMWH) (69.5%, n=373), direct oral anticoagulants (DOACs) (13.8%, n=74), unfractionated heparin (UFH) (9.9%, n=53), and direct thrombin inhibitors (DTIs) (3%, n=16). Most patients were admitted to the cardiovascular intensive care unit (CVICU) (19.7%, n=106), gastrointestinal transplant unit (17%, n=91), and hematology/oncology/bone marrow transplant service (15.1%, n=81). Protocol adherence improved from 86.4% in Phase 1 to 91.5% in Phase 2 (p=0.024). Stewardship recommendations were made in 33.9% (n=182) of encounters with 84.6% (n=154) accepted by primary teams. Common interventions included laboratory monitoring (40.6%, n=74), dose adjustments (39.1%, n=71), and anticoagulant changes (11.5%, n=21). A new in-hospital thrombosis occurred in 43 patients (21%), most of which were venous thromboembolism (79.1%, n=34), central line-associated (81.4%, n=35), non-occlusive (55.8%, n=24), and located in the upper extremity (55.8%, n=24). Associated comorbidities included ICU admission (55.8%, n=24), recent surgery (34.9%, n=15), and congenital heart disease (25.6%, n=11). Anticoagulation-related bleeding occurred in 6 patients with new thrombosis (14%), the majority (83.3%, n=5) being clinically relevant non-major bleeding. One ECMO patient experienced major bleeding. Bleeding rates did not differ between phases (11.1% vs. 16%, p=0.61). Although mean LOS remained similar between phases (89.7 days vs. 88.3 days, p=0.96), the time to therapeutic goal improved slightly from 48.6 hours to 45.1 hours (p=0.77). Hematology outpatient follow-up for patients with new thromboses improved from 55.6% to 66.7% (p=0.46). Conclusions: This single-institution experience reinforces the role of ASPs in ensuring appropriate anticoagulant dosing and monitoring for hospitalized pediatric patients. Implementation of the program improved adherence to protocols and was associated with high acceptance of stewardship recommendations. While this interim analysis did not show statistically significant changes in clinical outcomes such as LOS or time to achieve therapeutic anticoagulation, we believe this reflects the early stage of implementation. As the program matures and more data accrues, we anticipate further improvements in these metrics. This initiative provides a strong foundation for ongoing quality improvement efforts aimed at optimizing anticoagulation safety and outcomes.