A new anticoagulant for blood sampling tubes for platelet function tests1

Abstract

Abstract Background: The difficult pre-analytical conditions of platelet function diagnostics discourage its widespread use, e.g., to detect resistance to acetylsalicylic acid (ASA) and/or clopidogrel. Platelet activation during blood drawing and sample preparation cannot be prevented by citrate anticoagulation. Here, we tested a new blood sampling tube containing the anticoagulant benzylsulfonyl-D-Argininyl-Prolyl-4-amidinobenzylamide (Thrombovette®, Probe&go, Germany). Methods: A total of 46 emergency patients taking ASA and clopidogrel as well as 20 healthy volunteers were included in the study. Blood was drawn into Thrombovette® and citrate S-Monovette® tubes (Sarstedt AG&Co, Germany) and transported to the laboratory via the pneumatic tube system. Whole blood impedance aggregometry (model 560Ca, Chrono-Log, Havertown, PA, USA) was performed using collagen and ADP as platelet agonist (final concentrations 1 mg/L and 5 μM, respectively). Results: Reference ranges and cut-off values for the determination of drug resistance were obtained from the healthy cohort. Positive predictive values were 94.6% and 94.1% for inhibition of aggregation by ASA, and 68.0% and 53.3% for inhibition by clopidogrel using Thrombovette® and citrate S-Monovette®, respectively. Negative predictive values were 82.8% and 75.0% for ASA resistance and 87.8% and 83.3% for clopidogrel resistance using Thrombovette® and citrate S-Monovette®, respectively. Conclusions: Thrombovette® is a promising new system for blood sampling and could improve the validity of platelet function diagnostics.