Kaspar M, Ramsay M A, Nguyen A T, Cogswell M, Hurst G, Ramsay K J
Department of Anesthesiology, Baylor University Medical Center, Dallas, Texas 75246, USA.
Anesth Analg. 1997 Aug;85(2):281-5. doi: 10.1097/00000539-199708000-00007.
Tranexamic acid (TA) is a synthetic drug that inhibits fibrinolysis. It has been administered to decrease the use of blood products during cardiac surgery and orthotopic liver transplantation when infused in larger doses. A small-dose infusion of aprotinin causes a reduction in fibrinolysis and blood product requirement during orthotopic liver transplantation without apparent risk of intravascular thrombosis. This prospective study was designed to investigate whether a small-dose infusion of TA would be equally effective in reducing fibrinolysis and blood product transfusions during orthotopic liver transplantation. A double-blind, controlled study was undertaken to compare the efficacy of a small-dose TA infusion with that of a placebo. Thirty-two consecutive patients were randomized either to the TA group (n = 16), which received an intravenous infusion of 2 mg x kg(-1) x h(-1), or to the control group (n = 16), which received an identical volume of normal saline. Coagulation values were measured, a field rating was made by the surgeon, and a thromboelastogram was produced at four predetermined intervals throughout the case-before TA infusion was started, after portal vein ligation, 10 min after reperfusion, and at the end of surgery. Intraoperative transfusion requirements were recorded during the procedure and for the first 24 h postoperatively. A record was kept of any intraoperative epsilon-aminocaproic acid administered for uncontrolled fibrinolysis. The thromboelastogram clot lysis index was significant for lysis in the control group during both the anhepatic and the neohepatic phases (P < 0.01 and P < 0.05, respectively) when compared with the TA group. Fibrin degradation products were significantly increased (>20 microg/mL) in the control group at reperfusion (P < 0.03) and at the end of surgery (P < 0.01). D-dimers were also significantly increased (>1 mg/L) in the control group at the end of surgery (P < 0.04). Nine of the 16 control patients versus 3 of the 16 TA patients required epsilon-aminocaproic acid rescue for fibrinolysis. There were no other significant differences between groups. Transfusion requirements during surgery and for the first 24 h postoperatively did not differ significantly between the two groups. We conclude that the use of small-dose TA reduces fibrinolysis but not transfusion requirements during orthotopic liver transplantation.
氨甲环酸（TA）是一种抑制纤维蛋白溶解的合成药物。在心脏手术和原位肝移植中，大剂量输注TA可减少血液制品的使用。小剂量输注抑肽酶可减少原位肝移植期间的纤维蛋白溶解和血液制品需求，且无明显的血管内血栓形成风险。本前瞻性研究旨在调查小剂量输注TA在原位肝移植期间减少纤维蛋白溶解和血液制品输注方面是否同样有效。进行了一项双盲对照研究，以比较小剂量TA输注与安慰剂的疗效。32例连续患者被随机分为TA组（n = 16），接受2 mg·kg⁻¹·h⁻¹的静脉输注，或对照组（n = 16），接受相同体积的生理盐水。在整个手术过程中的四个预定时间点——开始输注TA前、门静脉结扎后、再灌注后10分钟和手术结束时，测量凝血值，由外科医生进行现场评分，并进行血栓弹力图检查。记录术中及术后24小时内的输血需求。记录任何因纤维蛋白溶解失控而术中给予的ε-氨基己酸。与TA组相比，对照组在无肝期和新肝期的血栓弹力图凝块溶解指数均有显著的溶解（分别为P < 0.01和P < 0.05）。对照组在再灌注时（P < 0.03）和手术结束时（P < 0.01）纤维蛋白降解产物显著增加（>20 μg/mL）。对照组在手术结束时D-二聚体也显著增加（>1 mg/L）（P < 0.04）。16例对照组患者中有9例与16例TA组患者中有3例因纤维蛋白溶解需要ε-氨基己酸抢救。两组之间无其他显著差异。两组在手术期间及术后24小时内的输血需求无显著差异。我们得出结论，在原位肝移植期间，使用小剂量TA可减少纤维蛋白溶解，但不能减少输血需求。
