Nilsson Caroline U, Engström Martin
Central Hospital Halmstad, Halmstad, Halland, Sweden.
Blood Coagul Fibrinolysis. 2007 Oct;18(7):619-22. doi: 10.1097/MBC.0b013e3282891cf1.
Fondaparinux is a new anticoagulant that interacts with antithrombin III and activated coagulation factor X resulting in an inhibition of the coagulation system. It has been successful in doses of 2.5 mg for thromboprophylaxis as well as in higher therapeutic doses of 5-7.5 mg. No optimal method for monitoring the effects of fondaparinux has been proposed. The aim of the present study was to investigate whether a viscoelastic coagulation analyzer, the Sonoclot (Sienco, Denver, Colorado, USA), could be used for in-vitro monitoring of fondaparinux. Different concentrations of fondaparinux were added in vitro to whole blood taken from eight volunteers. The blood samples mixed with the various amounts of fondaparinux were analyzed using the Sonoclot. The whole-blood activated partial thromboplastin time with the Hemochron Jr (ITC, Edison, New Jersey, USA) was used as the reference coagulation analysis. All analyses were started expeditiously, within 30 s from sampling, and were performed at 37 degrees C. The values of the Sonoclot parameter clot rate, which measures the rate of fibrin formation, fibrin polymerization and platelet-fibrin interactions, were significantly correlated to increasing concentrations of fondaparinux (R = -0.90). The Sonoclot parameters of activated coagulation time, time to peak and clot retraction had weaker, but still significant, correlations to fondaparinux concentrations. At prophylactic doses (0.38 microg/ml blood) the clot rate decreased 15% compared with the initial unanticoagulated value, whereas at therapeutic doses (1.53 microg/ml blood) there was a 27% decrease. In conclusion, the Sonoclot parameter clot rate could be of clinical value to individualize the fondaparinux dosage, especially the higher, therapeutic, dosages.
磺达肝癸钠是一种新型抗凝剂，它与抗凝血酶III和活化的凝血因子X相互作用，从而抑制凝血系统。2.5毫克的剂量用于血栓预防已取得成功，5 - 7.5毫克的更高治疗剂量也同样有效。目前尚未提出监测磺达肝癸钠效果的最佳方法。本研究的目的是调查一种黏弹性凝血分析仪——Sonoclot（美国科罗拉多州丹佛市的Sienco公司生产）是否可用于体外监测磺达肝癸钠。将不同浓度的磺达肝癸钠体外添加到从八名志愿者采集的全血中。使用Sonoclot对与不同量磺达肝癸钠混合的血样进行分析。以美国新泽西州爱迪生市ITC公司生产的Hemochron Jr检测的全血活化部分凝血活酶时间作为参考凝血分析。所有分析均在采样后30秒内迅速开始，并在37摄氏度下进行。Sonoclot参数凝块形成速率可测量纤维蛋白形成、纤维蛋白聚合和血小板 - 纤维蛋白相互作用的速率，其值与磺达肝癸钠浓度的增加显著相关（R = -0.90）。活化凝血时间、达到峰值时间和凝块回缩等Sonoclot参数与磺达肝癸钠浓度的相关性较弱，但仍具有显著性。在预防剂量（0.38微克/毫升血液）下，凝块形成速率与初始未抗凝值相比降低了15%，而在治疗剂量（1.53微克/毫升血液）下则降低了27%。总之，Sonoclot参数凝块形成速率对于个体化磺达肝癸钠剂量，尤其是较高的治疗剂量，可能具有临床价值。
