Foroughinia Farzaneh, Farsad Fariborz, Gholami Kheirollah, Ahmadi Somayeh
Department of Clinical Pharmacy, Shiraz University of Medical Sciences, Shiraz, Iran.
Rajaei Cardiovascular Medical and Research Center, Iran University of Medical Science, Tehran, Iran.
J Res Pharm Pract. 2015 Apr-Jun;4(2):73-8. doi: 10.4103/2279-042X.155754.
Thrombocytopenia is a common problem in cardiovascular surgery patients. However, heparin-induced thrombocytopenia (HIT) is a rare but life-threatening complication of prophylaxis or treatment with heparin. Prompt management of HIT with an alternative anticoagulant is necessary due to the extreme risk of thrombotic complications. Therefore, we evaluated the effects of danaparoid in the treatment of HIT in patients with cardiac surgery who are at moderate to high risk of HIT.
A prospective observational study involving 418 postcardiac surgery patients who received unfractionated heparin and low-molecular weight heparin was conducted in an educational tertiary cardiac care hospital in Iran. All patients were assessed for HIT type II based on thrombocytopenia and pretest clinical scoring system, the "4T's" score. HIT patients were treated with 1500-2500 units intravenous bolus danaparoid sodium followed by 200-400 units/h for a mean of 5 days. Successful response to danaparoid therapy, defined as augmentation in platelet count and improvement of thrombotic events was assessed in all patients treated with danaparoid.
According to pretest clinical score (4T's), the probability of HIT was high in 14 (3.3%) patients and intermediate in three ones (0.7%). 15 patients with HIT were treated with danaparoid. One death occurred in danaparoid-treated group due to persistent thrombocytopenia. The rest of patients were treated successfully with danaparoid without any major thrombotic complication.
According to our data and the previous studies', HIT can be managed prosperously with danaparoid in postcardiac surgery patients. However, with the absence of any increase in platelet count after 3-5 days of danaparoid therapy and/or the occurrence of a new thrombotic event, danaparoid cross-reactivity with heparin should be suspected.
血小板减少是心血管外科手术患者常见的问题。然而,肝素诱导的血小板减少症(HIT)是肝素预防或治疗过程中一种罕见但危及生命的并发症。由于血栓形成并发症的风险极高,因此需要及时使用替代抗凝剂来处理HIT。因此,我们评估了达那肝素在治疗心脏手术中发生HIT风险为中到高的患者中的效果。
在伊朗一家教育型三级心脏护理医院对418例接受普通肝素和低分子肝素的心脏手术后患者进行了一项前瞻性观察研究。根据血小板减少情况和预测试临床评分系统“4T”评分对所有患者进行II型HIT评估。HIT患者接受1500 - 2500单位静脉推注达那肝素钠治疗,随后以200 - 400单位/小时的速度持续治疗,平均治疗5天。对所有接受达那肝素治疗的患者评估其对达那肝素治疗的成功反应,定义为血小板计数增加和血栓事件改善。
根据预测试临床评分(4T),14例(3.3%)患者发生HIT的可能性高,3例(0.7%)患者可能性为中等。15例HIT患者接受了达那肝素治疗。达那肝素治疗组有1例患者因持续性血小板减少死亡。其余患者接受达那肝素治疗成功,未出现任何重大血栓并发症。
根据我们的数据和先前的研究,心脏手术后患者使用达那肝素可成功处理HIT。然而,如果在达那肝素治疗3 - 5天后血小板计数没有任何增加和/或出现新的血栓事件,应怀疑达那肝素与肝素存在交叉反应。