Effects of acute normovolemic haemodilution with 6% HES on coagulation<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

马瑞云　杨拔贤
北京大学人民医院麻醉科   北京，100044

Rui-yun Ma，Ba-xian Yang
Department of Anesthesiology, Peking University People's Hospital, Beijing 100044, China

Abstract

Objective：To investigate effects of acute normovolemic haemodilution with 6% HES(HES 200kD/0.5) on coagulation.
　　Methods：Twelve ASA Ⅰ～Ⅱpatients undergoing elective neurosurgery underwent moderate hemodilution to a target hematocrit of 30% and at the same time partes aequales Hydroxyethyl Starch(HES 200k/0.5)were infused within 20 min. Blood samples were taken at before haemodilution(T1), instant (T2) and 30 min(T3) after haemodilution. Blood routine, prothrombin time (PT), international normolized ratio (INR) ,activated partial thromboplastin time (APTT), fibrinogen (FIB) and thrombin-antithrombin complex (TAT) concentrations were measured.
　　Results：Compared with Time point T1, At Point T2 and Point T3 APTT, PT were significantly longer, and INR was significantly greater. There was no difference in thrombin-antithrombin complex (TAT) concentrations between every time point.
　　Conclusion：After haemodilution , thrombin-antithrombin complex concentration remained stable, which may suggests that haemodilution increased thrombin generation. The prolonged APTT suggests that hydroxyethyl starch has negative effects on coagulation.
　　Key words：Haemodilution;  Hydroxyethyl Starch; Blood coagulation
　　Corresponding author：Ba-xian Yang，marida1125@sina.com

临床实践表明，血液稀释可有效地减免异体血液的输注，避免输入异体血液而带来的多种并发症。近年来大量的体外实验^[1-5]研究提示，轻-中度血液稀释可能会增强凝血活性，甚至导致血液高凝状态^[6,7]。但在人体的临床研究比较少。贺斯已广泛应用于血液稀释中，但其对于凝血有较显著的负面作用^[5,8-10]，因此，本研究的目的是通过观察血液稀释后几种主要反映凝血功能参数的变化，探讨临床上以6%贺斯进行中度急性等容血液稀释对凝血功能的影响。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

一、资料与方法
　　1．观察病人的选择
　　选择ASAⅠ～Ⅱ级择期行神经外科手术的病人12例。年龄为25～53岁；无高血压、糖尿病及冠心病；术前肝、肾功能正常，凝血功能无异常；近3个月内未应用任何抗凝或止血药物及其它对凝血有明显影响的药物；
　　2．实验步骤
　　(1)病人入室前30分钟肌注东莨菪碱0.3mg。入室后静脉注射咪达唑仑0.03mg/kg。桡动脉穿刺置管(20G)，用于监测直接动脉压和采血。后行静脉全麻诱导和气管内插管：异丙酚1.5～2.0mg/kg，芬太尼3～4μg/kg，维库溴铵0.1mg/kg。气管内插管后接麻醉机行机械通气，呼吸频率为10次／分，潮气量为10ml/kg。经锁骨下行中心静脉穿刺置管，间断测定中心静脉压。术中以异氟醚、芬太尼、维库溴铵维持麻醉。
　　(2)麻醉平稳后，由桡动脉匀速采集全血，同时经外周静脉以同样速度输入6％贺斯(200k/0.5)行中度等容血液稀释。稀释过程中，监测心率、血压及中心静脉压。所采集的血液在室温下保存于采血袋中，采血量按以下公式计算：
　　估计全身血容量(EBV)=体重(kg)×70ml(男)或×65ml(女)
　　采血量=EBV×[(Hct1-Hct2)／Hctm]%
　　Hct1为稀释前红细胞压积；Hct2为目标红细胞压积；Hctm为Hct1和Hct2的平均值。
　　(3)由中心静脉置管取全血样本5ml，用于血常规检查；凝血状态检查：包括凝血酶原时间(PT)、国际正常化比值(INR)、部分激活凝血活酶时间(APTT)、纤维蛋白原(FIB)及凝血酶-抗凝血酶复合物(TAT)。采样的时间点分别为：诱导后行血液稀释前(T1)；血液稀释完成后即刻(T2)；血液稀释完成后30分钟(T3)。血样2小时内交血栓实验室专业人员按操作规范处理。
　　以上全部操作在手术开始前完成，整个过程中保证麻醉平稳，患者无任何外界损伤性刺激。

　　3．实验材料
　　中心静脉穿刺针和导管为美国ARROW(8F)，动脉穿刺针为B-D(20G)。
　　北京市血库统一血液采集袋(400ml)，抗凝剂为枸橼酸钠。
　　Hct、Hb、PLT的测定：全自动血细胞计数仪。样本保存：真空采血管(B-D Vacutainer)，抗凝剂K2EDTA，2ml规格。
　　PT、INR、APTT、FIB的测定：比浊法/血浆；样本保存：真空采血管(B-D Vacutainer)，抗凝剂枸橼酸钠与血样比为1：9，2.7ml规格。
　　TAT的测定：酶联免疫吸附法(ELISA)，试剂：上海太阳生物制品有限公司。
　　4．统计学处理：
　　所有数据均以均数±标准差(X±S)表示，以SPSS 10.0 for Windows对数据进行统计学分析处理, 行配对t检验，P<0.05为有统计学显著差异。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />

二、结果
　　1． 12例病人，其中男性7例，女性5例。平均年龄为36.3±9.1岁,平均身高为171.4±5.7cm，平均体重为70.2±8.5kg。平均采血量为735.8±139.9ml。
　　2．血液稀释后的Hct 都降低至30%左右；血液稀释后Hct、Hb显著低于稀释前(P<0.001)，达到中度血液稀释 (表1，图1)。
　　3．各凝血参数在血液稀释后(T2及T3)与稀释前(T1)相比较：
　　(1)PT及INR明显延长(P<0.001)，但仍在正常值范围内(见图2、3)。
　　(2)APTT显著延长(P<0.001)，且多数病例的APTT延长超过正常值范围(见图4)。
　　(3)FIB血浆浓度明显降低(H: P<0.01、H30: P<0.005)，但仍在正常值范围内(见图5)。
　　(4)血小板计数在血液稀释前、后无显著改变(见图5)；H和H30两点间各项指标无统计学差异。
　　(5)血液稀释前后，TAT血浆浓度变化无统计学差异(见图6)(H：P=0.837，H30：P=0.395)(见表1)。

6. Janvrin SB, Davies G, Greenhalgh RM. Postoperative deep vein thrombosis caused by intravenous fluids during surgery. Br J Surg 1980;67:690-3
7. Heather BP, Jennings SA, Greenhalgh RM. The saline dilution test -a preoperative predictor of DVT. Br J surg 1980;67:63--65
8. Jonge ED,Levi M.Effects of different plasma substitutes on blood coagulation:A comprative review.
9. Batle J, del Rio F, Lopez FM, et al: Effect of dextran on factor Ⅷ/von Willebrand factor structure and function. Thromb Haemost 1985;54:697-9.
10. de Jonge E ,Levi M, Berends F, et al:Impaired haemostasis by intravenous administration of a gelatin-based plasma expander in human subjects.Thromb Haemost 1998;79:286-90. 
11. Jesty J.The kinetics of inhibition of alpha-thrombosis.in human plasma.J Biol Chem 1986;261:10313-8. 
12. Jesty J.The kinetics of inhibition of thrombin by antithrombin in the presence of components of the hemostatic system. Blood 1985;66:1189-95. 
13. Tuman KJ, Spiess BD, McCarthy RJ, Ivankovich AD. Effects of progressive blood loss on coagulation as measured by thrumbelastography. Anesth and Analg 1987;66:856-863. 
14. Ruttmann TG, James MF, Aronson I. In vivo investigation into the effects of haemodilution with hydroxyethyl starch (200/0.5) and normal saline on coagulation . Br J Anaesth 1998;80:612-6.  
15. Ng KF, Lo JW. The development of hypercoagulability state ,as measured by thrombelastography, associated with intraoperative surgical blood loss .Anaesth Intensive Care 1996;24:20-5.
16. Ng KFJ, Lam CCK, Chan LC. In vivo effect of haemodilution with saline on coagulation: a randomized controlled trial. Br J Anaesth 2002;88:475--80.
17. Ruttmann TG, James MF, Finlayson J. Effects on coagulation of intravenous crystalloid or colloid in patients  undergoing peripheral vascular surgery.Br J Anaesth 2002;89(2):226-30.
18. Bock SC. Antithrombin Ⅲ and heparin cofactor Ⅱ.In:Colman RW,Hirsh J, Marder VJ,et al.Hemostasis and thrombosis:basic principles and clinical practice.4th ed. Philadelphia:Lippincott willizms & Wilkins, 2001:321-79.
19. Dalrymple-Hay M, Aitchison R,Collins P,et al:Hydroxyethyl starch induced acquired von Willebrand's disease.Clin Lab Haematol 1992:14:209-11.
20. Treib J, Haass A, Pindur G:Coagulation disorders caused by hydroxyethyl starch. Thrumb Heamost 1997:78;974-83.
21. Kuitunen A, Hynynen M,Salmenpera M, et al: Hydroxyethyl starch asa prime for cardio-pulmonary bypass:effects of two different solutions on haemostasis .Acta Anaesthesiol Scand 1993;37:652-8.
22. Conroy JM,Fishman RL, Reeves ST, et al : The effects of desmopressin and 6% hydroxyethyl starch on factor Ⅷ:C.Anesth  Analg 1996;83:804-7.
23. Treib J, HaassA, Pindur G,et al :HES200/0.5 is not HES 200/0.5.Influence of the c2/c6 hydroxyethylation ratio of hydroxyethel starch (HES)on hemorheology, coagulation and elimination kinetics.Thromb Haemost 1995;74:1452-6.
24. Stogermuller B,Stark J, Willschke H,et al: The Effect of Hydroxyethyl Starch 200 KD on Platelet Function. Anesth  Analg 2000;91:823-7.
25. Strauss RG. Volume replacement and coagulation: a comparative review .J Cardiothorac Anesth 1988;2(suppl 1):24-32.
26. ISBN7-81034-679-2 《现代血栓病学》 汪钟，郑植权主编。北京医科大学、中国协和医科大学联合出版社，1997年1月，第一版。458-78页。<?xml:namespace prefix = o ns = "urn:schemas-microsoft-com:office:office" />