L-精氨酸对兔大量输注库血后酸碱平衡和血栓弹力图的影响

Effects of L-arginine on acid-base balance and thromboelastograph in rabbits after banked-blood transfusion

目的:探讨兔大量输注库血后酸碱平衡和血栓弹力图(thromboelastograph,TEG)的变化以及L-精氨酸(L-arginine,L-Arg)对其的影响。方法:普通级新西兰大白兔50只,其中20只用来抽取全血做为实验用血,其余30只随机分为3组(n=10)。对照组:对实验动物进行放血(血容量的20%),维持30 min后输入等量库血,输血前5 min给予和25%L-Arg 300 mg/kg同等容量的生理盐水(1.2 mL/kg);假手术组:进行与对照组相同的麻醉、有创操作和监测,但不进行放血和输血的处理,在与对照组相同的时间给予25%L-Arg 300 mg/kg。L-Arg组:所有操作同对照组,只将生理盐水的输注改为25%L-Arg 300 mg/kg。各组动物分别于麻醉及有创操作完成后稳定10 min(T0)、放血结束即刻(T1)、输血结束即刻(T2)、输血结束60 min(T3)和输血结束120 min(T4)5个时点抽血进行动脉血气分析,于T1和T4时点抽血进行TEG的测定。结果:对照组和L-Arg组的血pH值先降后升,其中对照组T2时点血pH值显著低于T0和T1(P<0.05);假手术组各时点的血pH值均无明显变化。3组实验动物的碱剩余(base excess,BE)值持续降低,其中对照组和L-Arg组T2～T4时点的BE值均显著低于T0(P<0.05),假手术组T4时点的BE值明显低于T0时点(P<0.05)。对照组血乳酸(lactate,Lac)含量无明显变化;假手术组和L-Arg组血Lac含量逐渐下降,T3和T4时点的血Lac含量明显低于T0(P<0.05),且T1～T3时点的血Lac含量均明显低于对照组(P<0.05)。3组实验动物T0至T4时点的TEG组内和组间差异均无统计学意义(P>0.05)。结论:实验兔输血前给予L-Arg 300 mg/kg可以明显改善组织灌注,但对酸碱平衡影响不大;L-Arg对TEG的影响还需进一步实验证实。

Objective ：To investigate the effects of L-arginine （L-Arg） on acid-base balance and thromboelastograph （TEG） in rabbits after banked-blood transfusion. Methods： Fifty New Zealand white rab- bits, of which 20 were banked-blood donors, and the remaining 30 were randomly divided into 3 groups （n = 10）. Control group： hypovolemic models were made through blood loss by 20% of blood volume, and were retransfused with equal volume of banked-blood （ 14 days） 30 min later. Normal saline 1.2 mL/kg was given intravenously 5 min before transfusion ; Sham operation group ： the rabbits only received 25% L-Arg 300 mg/kg （ 1.2 mL/kg） intravenously at the same time-point as control group, without blood loss and banked-blood transfusion; L-Arg group： the rabbits received the same procedure as control group, equal volume of L-Arg was given as the control instead of normal saline. Blood gas/electrolyte analyses were determined before （T0） and after blood loss （T1）, immediately after banked-blood transfusion （T2）, 60 min （T3） and 120 min （T4） after banked-blood transfusion. TEG were checked only at TO and T4. Results： In control group and L-Arg group, pH values were declined after blood loss and banked-blood transfusion, and then increased after the first drop. The pH value of control group at T2 was significantly lower than that at TO and T1 （P 〈 0.05 ）. Base excess （BE） values continued to de- crease from TO to T4 of the three groups, which were significantly lower at T4 than at TO in sham operation group （ P 〈 0. 05 ）. As to the concentration of blood lactate （ Lac ）, there were no significant differences between the three groups at T0. In sham operation group and L-Arg group, Lac decreased from TO to T4 （P 〈 0.05 ）, which was significantly lower than that of control group at the same time-point （P 〈 0.05 ）. The TEG had no significant difference within and among the groups at TO and T4 （ P 〉 0.05 ）. Conclusion： L-Arg 300 mg/kg intravenous injection can improve tissue perfusion in rabbits receiving banked-blood transfusion, while there was little effect on acid-base balance and TEG.