Heparin dose adjustment required to maintain goal-activated partial thromboplastin time during therapeutic hypothermia

The Implementation of Targeted Temperature Management: An Evidence-Based Guideline from the Neurocritical Care Society

“…Heparin is partially cleared by renal mechanisms, especially at high doses, and its anticoagulant activity requires interaction with cofactor antithrombin III. The use of typical weight-based heparin doses may produce an exaggerated aPTT response in TH patients, but the exact PK mechanism (enzyme activity, protein binding, or filtration) has not been elucidated [174,175]. Lower initial bolus and infusion doses of heparin have been suggested during TH with close monitoring for changing heparin requirements during rewarming.…”

Short‐Term Heparin Kinetics during Catheter Ablation of Atrial Fibrillation

“…Although patients with delayed ACT kinetics displayed a slightly higher platelet count compared to group 1, it seems unlikely to have influenced the ACT kinetics as the difference was not significant (P = 0.08). A recent study suggests that the effect of UFH may be increased during therapeutic hypothermia (< 33°C) . Core temperature was not measured in our population but conditions of intervention were similar in our study population, which made hyperthermia unlikely as a cause of delayed ACT kinetics.…”

Antithrombotic therapy in patients with acute coronary syndrome complicated by cardiogenic shock or out-of-hospital cardiac arrest: a joint position paper from the European Society of Cardiology (ESC) Working Group on Thrombosis, in association with the Acute Cardiovascular Care Association (ACCA) and European Association of Percutaneous Cardiovascular Interventions (EAPCI)

“…During TTM, UFH dose requirements are reduced and prolonged infusion interruption may be required to allow adequate drug clearance, mandating tight drug monitoring using ACT. 68,69 Consensus statements:…”

“…93 During TTM, UFH requirement is drastically reduced, and guideline-recommended UFH dosing protocols should therefore not be used. 68,69 The UFH dose should be reduced by roughly 50% and frequent aPTT monitoring both during cooling and rewarming should be performed (Figure 3). 69 TTM has been associated with increased platelet activation in some studies 94 and reduced platelet reactivity in others.…”

“…68,69 The UFH dose should be reduced by roughly 50% and frequent aPTT monitoring both during cooling and rewarming should be performed (Figure 3). 69 TTM has been associated with increased platelet activation in some studies 94 and reduced platelet reactivity in others. 95,96 In resuscitated patients, TTM may cause mild platelet dysfunction although this has not been associated with an increased risk of bleeding in the absence of acidosis.…”