Evaluation of the activated clotting time and activated partial thromboplastin time for the monitoring of heparin in adult extracorporeal membrane oxygenation patients

Abstract

The heparin dose correlated better with aPTT relative to ACT and, thus, may be considered a more effective tool for the dosing of heparin in adult ECMO patients. Paired ACT and aPTT sample data suggested a poor relationship between these two anticoagulant monitoring tests.

Quantitative measurement of heparin in comparison with conventional anticoagulation monitoring and the risk of thrombotic events in adults on extracorporeal membrane oxygenation

“…Unlike the ACT or the activated partial thromboplastin time (aPTT), anti-factor Xa (antiXa) is a direct measure of heparin activity (1). ACT is poorly correlated to heparin dose and to aPTT in adults and in children antiXa levels track better with heparin dose, but the ideal monitoring strategy for anticoagulation during ECMO is unknown (2, 3). We sought to determine whether ACT, aPTT, or antiXa levels were associated with bleeding requiring transfusion or clotting events in adults on ECMO.…”

Ventilatory and Pharmacotherapeutic Strategies for Management of Adult Patients on Extracorporeal Life Support

“…Each test has its inherent advantages and disadvantages including availability, cost, turnaround time, influence from factors other than the effect of heparin, and laboratory interference, as well as varying amounts of data for the use of these tests in this setting (Table ). Although ACT is commonly used because of its availability, rapid turnaround time, and familiarity in the context of cardiopulmonary bypass, it appears to be the least reliable marker of heparin's effect during ECLS . Thromboelastography, which provides information about multiple aspects of the clotting cascade, may become more routinely applied in the future, especially if data emerge indicating that it can help optimize pump function and bleeding risk.…”

“…Although ACT is commonly used because of its availability, rapid turnaround time, and familiarity in the context of cardiopulmonary bypass, it appears to be the least reliable marker of heparin's effect during ECLS. [58][59][60][61] Thromboelastography, which provides information about multiple aspects of the clotting cascade, may become more routinely applied in the future, especially if data emerge indicating that it can help optimize pump function and bleeding risk.…”

Overview of Pharmacological Considerations in Extracorporeal Membrane Oxygenation

“…Anticoagulation monitoring studies have demonstrated a lack of correlation between the anti-Xa test and ACT or aPTT in all patient populations. 55,56 Irby and colleagues 57 demonstrated an association between subtherapeutic anti-Xa levels and an increased need for oxygenator exchanges, suggesting potential benefi ts of the anti-Xa test. The relationship between ACT and aPTT has also shown inconsistencies; better correlations have been found between heparin doses and aPTT than between heparin doses and ACT.…”