心脏直视手术后肝素诱导性血小板减少症的诊断与治疗经验

目的 探讨肝素诱导性血小板减少症（heparin-induced thrombocytopenia,HIT）的诊断及治疗经验.方法 自 1993年3月至2013年12月,高州市人民医院心脏外科共施行心脏直视手术18 156例,6例患者诊断疑似HIT.其中,男4例,女2例;年龄49～65岁;单纯人工机械瓣膜置换术2例,其中1例为二尖瓣再次置换;人工机械瓣膜置换术合并冠状动脉旁路术移植术2例;单纯冠状动脉旁路移植术2例,均为不停跳冠状动脉旁路移植术.症状出现时间为术后5～12 d,1例患者首要症状表现为血小板减少,其他5例患者均表现为肢体末梢淤黑.2例患者在本次术前存在肝素接触史,其他4例患者不能确定是否有肝素暴露史.第1例至第4例患者误诊为弥散性血管内凝血（DIC）,治疗方案错误.第5、6例获得及时诊断及治疗.诊断依据为Greinacher评分诊断系统,并重点与弥散性血管内凝血进行鉴别诊断;对于Greinacher评分达到6-8分的患者给予停用治疗用肝素及冲管用肝素盐水,停用双香豆素类药物,未进一步使用直接凝血酶抑制剂（DTI）.结果 第1例至第4例患者死亡,其中第1至第3例患者死于多脏器功能衰竭,第4例患者死于肺栓塞、低心排血量综合征、多脏器功能衰竭;第5例、第6例痊愈,病死率为66.7％.2例生存患者分别随访3.5年及1年,无血栓栓塞相关性疾病发生.结论 心脏直视手术后HIT是一种罕见但后果严重的并发症,只有对其有充分的理论认识,及时发现、早期干预才有可能挽救患者的生命,否则它将带来高病死率和并发症发生率.

Experience on diagnosis and therapy of heparin-induced thrombocytopenia after open-heart surgery

Objectives To summarize the experience on diagnosis and therapy of heparin-induced thrombocytopenia （HIT）.Methods From March 1993 to December 2013,18 156 patients underwent open-heart surgeries in Gaozhou People＇s Hospital.Among them,6 patients were suspected as HIT.There were 4 males and 2 females,aging from 49 to 65 years old.Two patients underwent mechanical valve replacement,including 1 redo case;2 patients underwent mechanical valve replacement plus coronary artery bypass graft （CABG）;2 patients underwent off-pump CABG.The timing of onset of thrombocytopenia ranged from 5-12 days after operation.One case presented with thrombocytopenia,the other 5 cases presented with mild limb thrombosis.Two cases had a history of heparin exposure,while the other 4 cases could not be confirmed.The first 4 cases were wrongly diagnosised with disseminated intravascular coagulation （DIC） and treated with incorrect therapy protocols.The last 2 cases were promptly diagnosised as HIT and treated properly.Greinacher scoring system was adopted for diagnosing and differential diagnosing with DIC.For patients with scores of 68,heparin and warfarin was stopped immediately.We did not use direct thrombin inhibitors （DTIs）.Results The first 3 cases died from multiple organ dysfunction syndrome （MODS）,the 4th case died from pulmonary embolism,low cardiac output syndrome and MODS.The 5th and the 6th patients recovered and discharged,who had been followed up for 3.5 years and 1 year correspondingly.No venous thromboembolic disease occurred.Conclusions HIT following openheart operation is a rare but critical complication.Comprehensive and prompt diagnosis and therapy can get more chances to save patients＇ lives,otherwise,the mortality and morbidity can be high.