Background: The activated partial thromboplastin time (aPTT) and anti-factor Xa (anti-Xa) test are often used as surrogate markers of heparin’s effects, though anti-Xa may be preferred due to less variability and closer relation to heparin’s activity in the body. The antithrombotic and hemostatic therapy oversight group at NYU Langone Health (NYULH) implemented a nurse-titrated protocol, utilizing anti-Xa to titrate and monitor time in therapeutic range with heparin.
Aims: To evaluate adherence to the nurse-driven continuous infusion unfractionated heparin protocol and assess time to therapeutic anti-Xa, median time in therapeutic range, and clinical outcomes including bleeding and thrombotic events.
Methods: This was a retrospective chart review. Adult patients (>18 years old) who received heparin based on nurse-driven titration protocol between March 2019 and June 2019 at NYULH were included. Patients that received heparin for less than 24 hours, had an interruption in heparin for more than 12 hours, or received a direct oral anticoagulant (DOAC) prior to heparin initiation were excluded. Data collection included baseline characteristics, relevant concomitant medications, heparin administration including bolus dose, infusion rate, length of therapy, time within therapeutic range, bleeding events, and thrombotic events. The primary outcome was adherence to the protocol. Secondary outcomes included time within therapeutic range, thrombotic or bleeding events.
Results: Adherence to the protocol, defined as deviation of not more than 25% of protocol elements, including but not limited to adequate bolus dose, correct body weight used, time to first anti-Xa, and correct adjustment (units/kg) in heparin dose based on anti-Xa was observed 85% of the time, with the majority of dose titrations occurring by nursing, per protocol in 82% of patients. Therapeutic anti-Xa levels were achieved at a median of 30 hours into IV UFH therapy.
Conclusions: It remains a challenge to achieve a stable goal anti-Xa level within 24 hours of heparin initiation.
To cite this abstract in AMA style:
Ahuja T, Williams M, Arnouk S, Lum D, Papadopoulos J, Raco V, Green D. AntiXa Heparin Dosing Protocol Evaluation at a Large Academic Medical Center [abstract]. Res Pract Thromb Haemost. 2021; 5 (Suppl 2). https://abstracts.isth.org/abstract/antixa-heparin-dosing-protocol-evaluation-at-a-large-academic-medical-center/. Accessed April 18, 2024.« Back to ISTH 2021 Congress
ISTH Congress Abstracts - https://abstracts.isth.org/abstract/antixa-heparin-dosing-protocol-evaluation-at-a-large-academic-medical-center/