An evaluation of monitoring possibilities of argatroban using rotational thromboelastometry and activated partial thromboplastin time

Background: Rotational thrombelastometry/thrombelastography with ROTEM (R) and TEG (R) is becoming available bedside in an increasing number of intensive care units, where many patients with heparin-induced thrombocytopenia (HIT) are treated. The study has been performed in an effort to find out whether ROTEM (R) could be an alternative to activated partial thromboplastin time (aPTT) when argatroban is used for anticoagulation. Methods: Argatroban was added in vitro to a series of citrated whole-blood samples from 10 healthy volunteers to obtain whole-blood concentrations of 0, 0.125, 0.25, 0.5, 1.0, 2.0, 4.0 and 8.0 mg/l. ROTEM (R) and whole-blood aPTT analyses were performed at each argatroban concentration. Correlation analyses were performed using the Spearman correlation analysis. Results: There was a significant and strong correlation between argatroban concentrations and clotting time (CT in ROTEM (R) analysis with INTEM) (P < 0.0001 and r=0.98). Also, the ROTEM (R) time to maximum clot formation velocity (MAXV-t) appeared to have a very strong and highly significant correlation to argatroban concentrations (P < 0.0001 and r=0.95). When we studied the correlation between aPTT and CT, we found a highly significant and strong correlation between these two analyses (P < 0.0001 and r=0.97), especially so in the clinically relevant therapeutic range up to 100 s aPTT prolongation for HIT patients. Conclusion: A significant and strong correlation was found between argatroban concentrations and several ROTEM (R) parameters. Rotational thrombelastometry/thrombelastography has a potential role in increasing the safety of argatroban anticoagulation in critically ill patients.