Original Research
Tuesday, November 14, 2023
08:30 AM–10:00 AM
Abstract
Introduction:
The use of weight-based unfractionated heparin (UFH) infusions is the standard of care in hospital management of venous thromboembolism (VTE). The initial dosing strategies in older adults and higher weight patients remain uncertain given differences in pharmacokinetics and concerns for over-anticoagulation.
Research Question or Hypothesis: Does the use of adjusted body weight (AdjBW)-based dosing of UFH improve time to therapeutic anti-Xa level in older adults and higher weight patients compared to total body weight (TBW)?
Study Design: We conducted a single-center, retrospective study involving older adults aged 65 years or older and patients weighing 100 kg or greater with suspected or confirmed VTE.
Methods: Patients received a weight based UFH infusion starting at 18 units/kg/hr with or without an 80 unit/kg bolus using either TBW or AdjBW for at least 24 hours, titrated every 6 hours to a target anti-Xa level of 0.3 to 0.7 units/mL. The primary endpoint was median time to first therapeutic anti-Xa level following initiation of UFH infusion in patients receiving AdjBW-based dosing versus those receiving TBW-based dosing. Statistical analysis for the primary endpoint was performed using the Mann Whitney U test in R (version 4.3.3).
Results: The median time to therapeutic anti-Xa levels was shorter in the AdjBW group compared to the TBW group (13.6 hours versus 21.0 hours; difference 5.32 hours (95% CI 0.23 to 9.92)). This finding was driven by those aged 65 years or older, and those who received a bolus dose of UFH at the start of the infusion.
Conclusion: Among older adults and higher weight adults with suspected or confirmed VTE, the use of AdjBW to guide heparin infusion initiation was associated with improved time to therapeutic anti-Xa levels.
Presenting Author
Arielle Norton PharmDSaint Joseph's University
Authors
Soyoung Kim PharmD
Cooper University Hospital
Sungwook Kim PhD
Saint Joseph's University
Lauren Igneri PharmD
Cooper University Hospital
Benjamin Pullinger PharmD
Saint Joseph's College of Pharmacy
Terence Chau PharmD
Cooper University Hospital
Justin Delic PharmD
Cooper University Hospital