限制性液体复苏对失血性休克大鼠肠损伤的影响

Effect of Limited Fluid Resuscitation on Intestinal Injury of Hemorrhagic Shock in Rats

目的 研究不同剂量液体复苏对失血性休克大鼠肠损伤及肠黏膜通透性的影响。方法 将72只SD大鼠随机分成4组（n=18）：高剂量液体复苏组（HLR组）、中剂量液体复苏组（MLR组）、低剂量液体复苏组（LLR组）及未复苏组（Sham组），前3组的液体复苏剂量分别为45、30和15 mL / （kg · h）。复苏后检测所有大鼠肠黏膜的通透性。于复苏后24、48及72 h，均分别抽取6只大鼠检测动脉血中乳酸和静脉血中肿瘤坏死因子-α （TNF-α）的水平，测量肠湿/干重比，进行小肠组织病理学检查并评分。结果 复苏后，HLR组的肠黏膜通透性高于其余3组（P＜0.05）。复苏3～8 h内，Sham组的所有大鼠均死亡，而其余3组大鼠均存活。术后24 h时LLR组的乳酸水平低于其余2组（P＜0.05）；HLR组的TNF-α水平在术后24、48及72 h均高于其余2组（P＜0.05），在48 h时，LLR组低于MLR组（P＜0.05）；术后24 h时，LLR组的肠湿/干重比最低，HLR组最高（P＜0.05）。HE染色结果显示，3组大鼠肠黏膜损伤严重程度均随时间好转，但在48和72 h时，LLR组的肠绒毛基本正常。结论 复苏剂量为15 mL / （kg · h）的限制性液体复苏能降低失血性休克大鼠术后早期酸中毒的程度和TNF-α的释放，降低肠黏膜通透性，减轻对肠道的损伤。

Objective To determine the effects of different volume fluid resuscitation on intestinal injury and the permeability of intestine in hemorrhagic shock rats. Methods Sprague-Dawley male rats （n=72） were randomly equally divided into 4 groups after the model establishment of blood pressure-controlled hemorrhage, 45, 30,and 15 mL / （kg · h）of fluid resuscitation were performed in high dosage of resuscitation （HLR）, moderate dosage of resuscitation （MLR）, and low dosage of resuscitation （LLR） group respectively, but rats of Sham group didn’t accept fluid resuscitation. After esuscitation, ten centimeters ileum was harvested for testing intestinal permeability. Then 6 rats of each group were sacrificed at 24, 48, and 72 hours after fluid resuscitation respectively. Over the specified time interval, blood was collected for testing levels of lactic acid and plasma tumor necrosis factor-α （TNF-α）. The ileums of 3 resuscitation groups were obtained for testing the ratio of wet weight to dry weight and observing the histological changes. Results After resuscitation, the intestinal permeability was higher in HLR group （P〈0.05）. At 3-8 hours after resuscitation, rats of Sham group were all died, and the other rats of 3 groups were all alive. The level of plasma lactic acid was lower in LLR group than those of other 2 groups at 24 hours （P〈0.05）. The levels of TNF-α were higher in HLR group than those of other 2 groups at 24, 48, and 72 hours （P〈0.05）, and at 48 hours, level of TNF-α in LLR group was lower than MLR group （P〈0.05）. At 24 hours after resuscitation, ratio of intestinal wet weight to dry weight in LLR group was the lowest, and HLR group was the highest （P〈0.05）. According to the histopathology, intestinal injuries of the 3 groups were tend to be remission with the time, and at 48 and 72 hours after resuscitation, intestinal villus of LLR group appeared to be normal. Conclusion Limited fluid resuscitation of 15 mL / （kg · h） could not only decrease the levels of lactic acid and TNF-α, but also moderate the intestinal permeability and the intestinal injury in early stage after shock and surgery.