重癥醫學科病人中肝素誘導的血小板減少癥

摘 要 肝素誘導的血小板減少癥（HIT）是一種與肝素相關的嚴重副反應。其中II型HIT是一種免疫介導的常發生在使用普通肝素、但較少發生在使用低分子量肝素病人中的血栓形成并發癥，可見于各臨床專科，但易被臨床醫師忽視或漏診，特別是重癥醫學科危重病人普遍存在血小板減少現象且通常可由HIT外的其它病癥所致，診斷較為困難。應用4T評分表有助于這類病人的確診與治療用藥的選擇。確診HIT需實驗室檢查發現存在HIT抗體，而血小板功能檢測與抗原檢測相結合可提高診斷試驗的特異性和敏感度。HIT治療較棘手，嚴重者會危及生命，故臨床疑診HIT即應盡早開始替代抗凝治療，治療藥物可選擇直接凝血酶抑制劑和Xa因子抑制劑。

關鍵詞 肝素誘導的血小板減少癥 達那肝素 磺達肝素 來匹盧定 阿加曲班

中圖分類號：R973.2; R558.2 文獻標識碼：A 文章編號：1006-1533(2012)07-0012-05

Heparin-induced thrombocytopenia in intensive care patients

Zhang Bin

（ICU， Affiliated Hospital of Nantong University， Nantong， 226001）

Abstract Heparin-induced thrombocytopenia (HIT) is one of the most serious adverse events associated with heparin. HIT type II is an immune-mediated prothrombotic complication， which is more often caused by unfractionated heparin than low-molecular-weight heparin. It can be found in every clinical special department that diagnosis is often missed or ignored by the clinicians. There are a lot of difficulties in the diagnosis of HIT in the ICU as thrombocytopenia is universal in these patients and usually caused by rather conditions than HIT. The 4T’s score may be helpful in establishing the diagnosis and treatment of these patients. The diagnosis of HIT requires HIT antibodies existence found in the laboratory testing. The combination of functional and antigen assays has the highest performance in terms of specificity and sensitivity. The treatment of HIT is difficult， and there is a life-threatening in severe patients. To avoid serious bad consequence of HIT， alternative therapeutic anticoagulation should be initiated as soon as possibly based on high clinical suspicion. For treatment of HIT， the alternative anticoagulants such as the direct thrombin inhibitors and factor Xa inhibitors are approved.

Key Words heparin-induced thrombocytopenia; danaproid; fondaparinux; lepirudin; argatroban

肝素是一種在凝血過程中由肥大細胞和嗜堿粒細胞釋放的抗凝物質，在體內、體外均具有很強的抗凝活性，是臨床上常用的抗凝劑、尤其是用于血栓栓塞性疾病的防治[1]。肝素誘導的血小板減少癥（HIT）是一種肝素誘發、免疫介導的促血栓形成并發癥，常見于普通肝素（UFH）、但較少發生在低分子量肝素（LMWH）治療中或治療后，是與肝素有關的最嚴重的副反應。盡管HIT的發生率不高（在UFH治療者中約為1%～5%）[1]，但可見于各臨床專科且易被臨床醫師忽視、常造成漏診，治療亦較棘手，嚴重者會危及生命。為避免HIT對病人造成嚴重不良后果，臨床醫師應給予高度關注。……