Argatroban versus Lepirudin in critically ill patients (ALicia): a randomized controlled trial

Abstract

Introduction: Critically ill patients often require renal replacement therapy accompanied by thrombocytopenia. Thrombocytopenia during heparin anticoagulation may be due to heparin-induced thrombocytopenia with need for alternative anticoagulation. Therefore, we compared argatroban and lepirudin in critically ill surgical patients.

Methods: Following institutional review board approval and written informed consent, critically ill surgical patients more than or equal to 18 years with suspected heparin-induced thrombocytopenia, were randomly assigned to receive double-blind argatroban or lepirudin anticoagulation targeting an activated Partial Thromboplastin Time (aPTT) of 1.5 to 2 times baseline. In patients requiring continuous renal replacement therapy we compared the life-time of hemodialysis filters. We evaluated in all patients the incidence of bleeding and thrombembolic events.

Results: We identified 66 patients with suspected heparin-induced thrombocytopenia, including 28 requiring renal replacement therapy. Mean filter lifetimes did not differ between groups (argatroban 32 ± 25 hours (n = 12) versus lepirudin 27 ± 21 hours (n = 16), mean difference 5 hours, 95% CI -13 to 23, P = 0.227). Among all 66 patients, relevant bleeding occurred in four argatroban- versus eleven lepirudin-patients (OR 3.9, 95% CI 1.1 to 14.0, P = 0.040). In the argatroban-group, three thromboembolic events occurred compared to two in the lepirudin group (OR 0.7, 95% CI 0.1 to 4.4, P = 0.639). The incidence of confirmed heparin-induced thrombocytopenia was 23% (n = 15) in our study population.

Conclusions: This first randomized controlled double-blind trial comparing two direct thrombin inhibitors showed comparable effectiveness for renal replacement therapy, but suggests fewer bleeds in surgical patients with argatroban anticoagulation.

Trial registration: Clinical Trials.gov NCT00798525. Registered 25 November 2008.

Figure 1

Trial flow chart. Data are presented as mean ± SD, n = number of patients, sec = seconds. SD, standard deviation.

Figure 2

Kaplan-Meier analyses of time till filter clotting.