限制性液体复苏对非控制失血性休克大鼠脑功能的影响

Influence of limited fluid resuscitation on brain function of rats with non-controlled hemorrhagic shock

[目的]探讨不同的复苏压力对非控制失血性休克大鼠脑功能的影响。[方法]采用修订的Capone等方法制备创伤非控制失血性休克模型。将60只SD(Sprague-Dawley)大鼠随机分为6组:NC组(正常对照组)、NF组(休克不复苏组)、限制性液体复苏组(NS40组、NS60组)、大量液体复苏组(NS80组、NS100组)。实验过程分4期,急性创伤出血期:制备模型期(30min);院前急救期(31min～90min):模型制备成功后各液体复苏组在大鼠的平均动脉压(MAP)降至35mmHg～40mmHg(1mmHg=0.133kPa)时分别给予生理盐水输注,使血压维持在各相应目标压力水平,输液1h;院内治疗期(91min～210min):各液体复苏组均给予手术止血、回输血液及给予足量的液体输注,保持大鼠的MAP≥90mmHg。观察期(211min至72h):动物放回笼内,自由饮水、进食。[结果]限制性液体复苏组的血乳酸值较大量液体复苏组低(P<0.05),血细胞比容明显高于大量液体复苏组;脑组织病理学损害程度较大量液体复苏组轻;限制性液体复苏提高了大鼠早期(4h)和72h的存活率;存活超过72h的NS40组的3只大鼠,全身功能分级评分(OPC)和神经功能缺陷评分(NDS)存在明显神经功能缺陷和严重残疾;而存活超过72h的NS60组的9只大鼠,OPC和NDS评分基本正常。[结论]限制性液体复苏对脑功能具有保护作用,早期限制性液体复苏维持大鼠的MAP在60mmHg可较好地改善其预后。

Abstract Objective： To probe into the influence of different recovery pressures on brain function of rats with non controlled hemorrhagic shock. Methods. The modified Capone＇s method was used to make an uncontrolled hemorrhagic shock model. A total of 60 Sprague Dawley rats were randomly divided into six groups：NC group, normal control group; NF group, shock non resuscitation group ; NS40, NS60 group （limited fluid resuscitation group）; and NS80, NS100 group （large volume fluid resuscitation group）. The experimental process was divid ed into four phases： acute traumatic hemorrhage period： preparation of model（30 rain） ;Pre hospital emergency period（31 min～90 rain） .af ter the models were successfully made, when the mean arterial pressure （MAP） in rats reduced to 35 mmHg^40 mmHg, saline infusion was given to make blood pressure maintain the corresponding target pres sure level, infusion for lh; hospital treatment period （91 rain ～ 210 rain） .fluid resuscitation group were treated with surgery to stop bleed ing,blood transfusion and a sufficient amount of liquid infusion were given to keep the rats＇ MAP≥90 mmHg. Observation period（211 rain to 72 h）：the animal were taken back into the cage,and made the free access to water and eat. Results：Findings showed that the average val ue of lactic acid in blood in limited fluid resuscitation groups was sig nificantly lower than that of large volume fluid resuscitation groups （P〈0.05） ;The counts of hematocrit（HCT）in limited fluid resuscita tion groups was significantly higher than that of large volume fluid resuscitation groups;The extent of brain tissue pathology damage alle viate compared with the large amount of fluid resuscitation group;lim ited fluid resuscitation improved the early（4 h） and 72 h survival rate of rats;in 3 rats who survived for more than 72 h in the NS40 group, the systemic functional classification score（overall performance catego ry OPC） and neurological deficit score （neurologic deficit scoring, NDS,） showed that there are significant neurological defects and se vere disability;For nine rats survived for more than 72 h in the NS60 group,OPC and NDS score were normal. Conclusion：Limited fluid re suscitation has a protective effect on brain function, early limited fluid resuscitation to maintain MAP at 60 mmHg can better improve the prognosis of the rats.