Chakravarthy Murali, Muniraj Geetha, Patil Swapnil, Suryaprakash Sharadaprasad, Mitra Sona, Shivalingappa Benak
Department of Anesthesia, Critical Care & Pain Management, Fortis Hospitals, Bannerghatta Road, Bangalore, India.
Ann Card Anaesth. 2012 Apr-Jun;15(2):105-10. doi: 10.4103/0971-9784.95072.
Postoperative hemorrhagic complications is still one of the major problems in cardiac surgeries. It may be caused by surgical issues, coagulopathy caused by the side effects of the intravenous fluids administered to produce plasma volume expansion such as hydroxyl ethyl starch (HES). In order to thwart this hemorrhagic issue, few agents are available. Fibrinolytic inhibitors like tranexamic acid (TA) may be effective modes to promote blood conservation; but the possible complications of thrombosis of coronary artery graft, precludes their generous use in coronary artery bypass graft surgery. The issue is a balance between agents that promote coagulation and those which oppose it. Therefore, in this study we have assessed the effects of concomitant use of HES and TA. Thromboelastogram (TEG) was used to assess the effect of the combination of HES and TA. With ethical committee approval and patient's consent, 100 consecutive patients were recruited for the study. Surgical and anesthetic techniques were standardized. Patients fulfilling our inclusion criteria were randomly allocated into 4 groups of 25 each. The patients in group A received 20 ml/kg of HES (130/0.4), 10 mg/kg of T.A over 30 minutes followed by infusion of 1 mg/kg/hr over the next 12 hrs. The patients in group B received Ringer's lactate + TA at same dose. The patients in the Group C received 20 ml/kg of HES. Group D patients received RL. Fluid therapy was goal directed. Total blood loss was assessed. Reaction time (r), α angle, maximum amplitude (MA) values of TEG were assessed at baseline, 12, 36 hrs. The possible perioperative myocardial infraction (MI) was assessed by electrocardiogram (ECG) and troponin T values at the baseline, postoperative day 1. Duration on ventilator, length of stay (LOS) in the intensive care unit (ICU) were also assessed. The demographical profile was similar among the groups. Use of HES increased blood loss significantly (P < 0.05). Concomitant use of TA reduced blood loss when used along with HES. r value was prolonged at 12 hours in all the groups and α angle was reduced at 12 hours in all the groups, where as MA value was reduced at 12 th hour in the HES group compared to the baseline and increased in TA + HES group. These findings were statistically significant. No significant change in Troponin T values/ECG, duration of ventilation and LOS ICU was observed. No adverse events was noticed in any of the four groups. HES (130/0.4) used at a dose of 20 ml/kg seems to produce coagulopathy causing increased blood loss perioperatively. Hemodilution produced by fluid therapy seems to produce Coagulopathy as observed by TEG parameters. Concomitant use of TA with HES appears to reverse these changes without causing any adverse effects in patients undergoing OPCAB surgery.
术后出血性并发症仍是心脏手术中的主要问题之一。它可能由手术问题引起，也可能由静脉输注用于扩充血浆容量的液体（如羟乙基淀粉（HES））的副作用导致的凝血功能障碍引起。为了克服这一出血问题，可用的药物很少。像氨甲环酸（TA）这样的纤维蛋白溶解抑制剂可能是促进血液保护的有效方式；但冠状动脉移植血栓形成的可能并发症，限制了它们在冠状动脉搭桥手术中的广泛使用。这个问题是促进凝血和抑制凝血的药物之间的平衡。因此，在本研究中，我们评估了同时使用HES和TA的效果。采用血栓弹力图（TEG）来评估HES和TA联合使用的效果。经伦理委员会批准并获得患者同意后，连续招募了100例患者进行该研究。手术和麻醉技术标准化。符合纳入标准的患者被随机分为4组，每组25例。A组患者接受20 ml/kg的HES（130/0.4），30分钟内静脉注射10 mg/kg的TA，随后在接下来的12小时内以1 mg/kg/小时的速度输注。B组患者接受相同剂量的乳酸林格液+TA。C组患者接受20 ml/kg的HES。D组患者接受乳酸林格液。液体治疗以目标导向。评估总失血量。在基线、12小时、36小时时评估TEG的反应时间（r）、α角、最大振幅（MA）值。通过基线、术后第1天的心电图（ECG）和肌钙蛋白T值评估围手术期可能发生的心肌梗死（MI）。还评估了呼吸机使用时间、重症监护病房（ICU）的住院时间（LOS）。各组之间的人口统计学特征相似。使用HES显著增加了失血量（P<0.05）。与HES同时使用TA可减少失血量。所有组在12小时时r值均延长，所有组在12小时时α角均减小，而与基线相比，HES组在12小时时MA值减小，TA+HES组MA值增加。这些发现具有统计学意义。未观察到肌钙蛋白T值/ECG、通气时间和ICU住院时间有显著变化。四组中均未发现不良事件。以20 ml/kg的剂量使用HES（130/0.4）似乎会导致凝血功能障碍，使围手术期失血量增加。液体治疗引起的血液稀释似乎会导致凝血功能障碍，这可通过TEG参数观察到。在接受非体外循环冠状动脉搭桥手术的患者中，TA与HES同时使用似乎可逆转这些变化，且不会引起任何不良反应。
