Comparison of Time to Therapeutic aPTT in Patients who Received Continuous Unfractionated Heparin after Implementation of Pharmacy-wide Intervention Alerts

Abstract

For patients on continuous IV unfractionated heparin (UFH), failing to achieve a therapeutic aPTT by 24 hours can be associated with increased morbidity. A pharmacy clinical surveillance system (PCSS) subtherapeutic aPTT alert was implemented at our institution to improve achievement of therapeutic aPTT goals by 24 hours. The primary objective was the time to achieve the minimum goal aPTT before and after the alert implementation. The secondary objectives were to examine the percentage of patients who achieved the minimum goal aPTT by 24 hours and the number of dose changes to achieve the minimum goal aPTT. A single-center retrospective study was conducted to include all adult inpatients receiving a continuous UFH infusion during a 3-month period prior to the implementation of a subtherapeutic aPTT alert and a 3-month period after implementation. 317 patients were included in the analysis. The average time to achieve the minimum goal aPTT was 21.8 hours prior to alert implementation and 15.4 hours after implementation ( = .002). The percent of patients who achieved the minimum goal aPTT by 24 hours was 65.7% prior to alert implementation and 82.4% after implementation ( = .035). The average number of dose changes necessary to achieve aPTT value to the minimum goal aPTT prior to alert implementation was 1.67 and 1. 98 after implementation ( = .68). This analysis showed that implementation of a PCSS subtherapeutic aPTT alert for patients on continuous UFH infusions may ensure patients reach goal aPTT faster and facilitate a higher percent of patients who achieve the minimum goal aPTT by 24 hours.

Therapeutic inefficacy of protocol driven intravenous unfractionated heparin infusion in the current era

“…This study highlights the current trends of therapeutic efficacy achieved with UFH and need to switch to LMWH as failure to reach the therapeutic range within the first 24 h of IV UFH therapy has been shown to have adverse outcomes [ 6 ]. Our findings are similar to other studies that have studied these trends with Ting et al [ 7 ] reporting only 40 % of patients spending their time in therapeutic range whereas Alsulaiman et al [ 8 ] reported only 25 % of their patient reaching therapeutic aPTT in 24 h. Several randomized controlled trials have shown the superiority of LMWH over UFH in decreasing death, myocardial infarction, angina or urgent revascularization without significantly increasing the risk of major bleeding episodes [ 3 , 4 ] With 80 % of the patients eligible for LMWH therapy, this clinical benefit along with having an ease of administration and more predictable pharmacokinetics, can potentially lead to better patient outcomes, higher levels of therapeutic efficacy, and decrease in hospital resources.…”

Evaluation of Antifactor-Xa Heparin Assay and Activated Partial Thromboplastin Time Values in Patients on Therapeutic Continuous Infusion Unfractionated Heparin Therapy

“…This investigation demonstrated that the implementation and use of a PCSS resulted in a decrease in the average time to obtain a therapeutic aPTT, from 21.8 to 15.4 hours ( P value = .002). 17 Shortly thereafter, Schurr et al published data on the implementation of a nurse-driven, weight-based heparin nomogram in which the mean time to a therapeutic aPTT was 11.7 hours, without an increase in supertherapeutic aPTT values. 18 This time to achieve a therapeutic aPTT using the aPTT nurse-driven dosing protocol is similar to a recently published study that demonstrated a time to achieve therapeutic anticoagulation using the anti-Xa of 16 hours.…”