2025 Southeastern Residency Conference

Tittle: Description of a 24-hour Therapeutic Target in Hospitalized Patients with Acute Coronary Syndrome or Atrial Fibrillation Before and After Implementation of a Maximum Initial Weight-Based Unfractionated Heparin Dosing Limit
 
Authors: Ivonne Marie Santiago Lopez, Kristen Keen, Justin Hodges, Ruthanne Baird, Catherine L. Wente, Dustin Wilson & Richard Drew
Cape Fear Valley Betsy Johnson Hospital – Dunn, NC
 
Objective: To describe the rate of 24-hour therapeutic target attainment in hospitalized adult patients ³ 85 kg with ACS or AF receiving UFH before and after implementation of a maximum initial dose protocol.


Self-Assessment Question: What is one reason that dose capping was implemented in this study?

Background: Unfractionated heparin (UFH) is commonly used for anticoagulation in critically ill patients but presents challenges in dosing for those weighing over 100 kg due to altered pharmacokinetics. Conservative dosing practices, such as capping doses, can delay therapeutic target attainment, potentially increasing the risk of adverse outcomes like venous thromboembolism (VTE) and coronary events. This study evaluates the impact of a weight-based, capped UFH dosing protocol on 24-hour therapeutic target attainment and bleeding complications in patients with acute coronary syndrome (ACS) and/or atrial fibrillation (AF)
Methods: This retrospective cohort study reviews medical records from patients admitted to Cape Fear Valley Betsy Johnson and Central Harnett Hospitals between September 2023 and December 2024. Eligible patients (≥ 85 kg with ACS/AF as dose cap begins at this weight) who received UFH were analyzed for the rate of achieving therapeutic levels within 24 hours before and after the implementation of a weight-based capped dosing protocol in May 2024. Secondary outcomes include the incidence of bleeding complications, number of coagulation tests required to achieve therapeutic targets (anti-Xa 0.3 – 0.7 units/mL or aPTT 53 – 73 seconds, and the use of heparin reversal agents. Data were collected via electronic health records (EHR) and analyzed using an intention-to-treat approach with JMP version 17.


Results: The primary outcome of achieving therapeutic anticoagulation at 24 hours was observed in 78% of patients in the control group, compared to 64% in the intervention group (OR 1.09; 95% CI 0.4,2.96). Regarding secondary outcomes, bleeding complications were reported in 7% of the first group and 12% in the second group, with all cases being minor. Protamine was not administered in any of the patients during their hospital stay. The number of coagulation laboratory draws required to achieve therapeutic targets was lower in the control group, with 60% patients needing only one draw compared to 46% in the intervention group.

Conclusions: There was no statistically significant difference between the groups in achieving therapeutic targets at 24 hours. While no major bleeding events occurred in either group, the intervention group had a higher incidence of minor bleeding. Additionally, neither group required protamine for reversal. These findings suggest that, overall, both treatments were safe, but further research with a larger sample size is needed to better understand the true impact of the intervention.