Evaluation of the Use of Argatroban or Bivalirudin for the Management of Suspected Heparin-Induced Thrombocytopenia in the Setting of Continuous Renal Replacement Therapy

Abstract

Studies have shown an association between continuous renal replacement therapy (CRRT) and thrombocytopenia. Patients on CRRT usually receive unfractionated heparin (UFH), and heparin-induced thrombocytopenia (HIT) is frequently suspected as a potential cause of thrombocytopenia. In the setting of HIT suspicion, changes in anticoagulation may put patients at risk of developing thromboembolic events or adverse medication effects. Purpose: The purpose of this study was to investigate current management of anticoagulation in patients with suspected HIT while on CRRT and identify complications associated with anticoagulation in this setting. Methods: This is a retrospective study of patients on CRRT with suspicion for HIT. Prevalence of HIT and anticoagulant use were collected for all patients. Outcomes included thromboembolic and bleeding events, final therapeutic doses of each anticoagulant, and time to reach therapeutic range. Thromboembolic and bleeding outcomes were compared between anticoagulants. Results: From January 2013 through December 2015, 74 patients were identified with suspicion of HIT while on CRRT. During the period of HIT suspicion, 20 patients received argatroban, 18 received bivalirudin, 1 received fondaparinux, 4 received UFH infusions, 10 received prophylactic dosing subcutaneous UFH, and 21 received no anticoagulation. The median final therapeutic doses of argatroban and bivalirudin were 1.00 μg/kg/min and 0.075 mg/kg/h, respectively, with no difference in time to therapeutic range (17.6 h vs 18.2 h, P = .485). Compared with bivalirudin, patients treated with argatroban had significantly more therapeutic activated partial thromboplastin time (aPTT) values (54.5% vs 42.8%, P = .008). Four patients (20.0%) treated with argatroban and 5 patients (27.8%) treated with bivalirudin experienced major bleeding ( P = .709). Three patients (15.0%) treated with argatroban and 4 patients (22.2%) treated with bivalirudin experienced thromboembolic events ( P = .687). Conclusion: Argatroban and bivalirudin were associated with similar rates of bleeding and thromboembolic events during the period of concurrent CRRT and thrombocytopenia, although patients treated with argatroban had more therapeutic aPTT values.