3种复苏液体对控制性失血性休克大鼠适宜血压高度影响的研究

目的 探讨3种不同复苏液体复苏控制性失血性休克大鼠的适宜血压高度.方法 分别以35%和45%放血量复制失血性休克模型.将180只SD大鼠随机分组,分别采用乳酸林格液(LR)、高渗氯化钠右旋糖酐(HSD)和LR+羟乙基淀粉(HES)溶液进行液体复苏,观察平均动脉压(MAP)分别维持在60、80和100 mm Hg(1 mm Hg=0.133 kPa)时动物血流动力学指标[包括左心室收缩压(LVSP)、左心室压力上升或下降最大速率(±dp/dt max)]的变化,同时观察血气及从复苏开始至12 h的存活率.结果 35%失血性休克时,LR组和LR+HES组能够较好维持设定的MAP值;HSD组MAP不能达到100 mm Hg,最高维持在85 mm Hg左右.45%失血性休克时,LR组和HSD组MAP也不能达到100 mm Hg水平;输注LR时MAP维持在85 mm Hg左右,输注HSD时MAP维持在80 mm Hg,输注LR+HES时MAP维持在60 mm Hg,休克大鼠的血流动力学指标和血气改善均较好.从总体上来看,LR+HES组12 h存活率高于其他各组,其中以输注LR+HES使MAP维持在60 mm Hg时存活率最高,而输注HSD的存活率最低.结论 不同程度休克时不同液体复苏的维持适宜血压高度不同,在中、重度休克时,输注LR到MAP 85～100 mm Hg、输注LR +HES到MAP 60 mm Hg、输注HSD到MAP 80 mm Hg为复苏时的适宜血压高度,能较好地改善失血性休克动物的血流动力学指标,发挥较好的复苏效果.

The optimal resuscitation pressure of several resuscitation fluids in controlling hemorrhagic shock in rats

OBJECTIVE: To investigate the optimal mean blood pressure of different resuscitation fluids in resuscitating hemorrhagic shock in rats. METHODS: One hundred and eighty Sprague-Dawley (SD) rats were used to reproduce hemorrhagic shock model by 35% and 45% depletion of blood volume, and they were randomly divided into Lactated Ringer solution (LR), 7.5% NaCl/6% Dextran 40 (HSD), and LR+hydroxyethly starch (HES) groups. Mean arterial pressure (MAP) was maintained at 60, 80 and 100 mm Hg (1 mm Hg=0.133 kPa) respectively with these fluids. Left intraventricular systolic pressure (LVSP), the maximal change rate of left intraventricular pressure (+/-dp/dt max), blood gases and 12-hour survival rate were observed. RESULTS: In 35% hemorrhagic shock rats, LR and LR+HES could better maintain the MAP at the set level, but HSD could not maintain MAP at 100 mm Hg, reaching only 85 mm Hg. In 45% hemorrhagic shock rats, LR and HSD, also could not elevate MAP to 100 mm Hg, and LR infusion could restore MAP to about 85 mm Hg, HSD to 80 mm Hg and LR+HES to 60 mm Hg. Overall 12-hour survival rate was highest in group with LR+HES to maintain MAP at 60 mm Hg with satisfactory hemodynamic parameters and blood gases. HSD group ended up with a lowest survival rate. CONCLUSION: Different fluids to resuscitate hemorrhagic shock showed a different optimal MAP. LR between 85-100 mm Hg, HSD at 80 mm Hg and LR+HES at 60 mm Hg, may throw better effect on resuscitating moderate and severe hemorrhagic shock.