聚环氧乙烷对内毒素休克兔肾血流动力学的影响

Effect of polyethylene oxide on renal hemodynamics in rabbits with endotoxin shock

目的应用超声监测内毒素休克新西兰兔肾血流,观察聚环氧乙烷(PEO)对内毒素休克兔肾血流的影响和肾脏的保护作用。方法健康新西兰白兔20只,随机分成两组,生理盐水组(NS)和溶于生理盐水的减阻剂组(PEO),每组10只。每只兔静脉注射内毒素0.6 mg/kg造内毒素休克兔模型。待血压下降≥30%时开始复苏,NS组使用生理盐水复苏,5 ml.h-.1kg-1),PEO组使用等剂量含20 ng/g PEO的生理盐水复苏。分别于休克前、休克期、复苏1 h后经超声观察肾血流动力学指标并抽血查肾功能。试验全程监测心率和动脉血压。结果两组兔各级肾动脉休克期流速明显低于休克前(P<0.05),动脉搏动指数(PI)和阻力指数(RI)明显增高;复苏1 h后,NS组各级肾动脉血流流速下降,三级肾静脉流速减慢,PI、RI无明显降低;而PEO组肾段动脉及叶间动脉流速较休克前明显增快(P<0.05),三级动脉PI、RI较之NS组相比明显下降(P<0.05)。肾功能指标:两组兔休克期BUN、Cr均升高,复苏1 h后PEO组各项指标明显低于NS组(P<0.05)。结论小剂量聚环氧乙烷能够有效增加感染性休克肾脏的血流灌注,对脓毒血症及感染性休克所致的早期肾脏损害有明显改善作用。

Objective To investigate the effect of polyethylene oxide（PEO） on renal blood flow and its renoprotective effect in rabbits with endotoxin sepsis.Methods Twenty normal New Zealand white rabbits were randomly divided into normal saline（NS） group and PEO group（n=10）,and endotoxin shock was induced by an intravenous injection of 0.6 mg/kg lipopolysaccharide.Resuscitation was performed when the blood pressure of the rabbits showed a 30% decline,using NS（in NS group） or the mixture of equal volumes of NS and 20 ng/g PEO（in PEO group） perfused at the rate of 5 ml/kg per hour.Before and during shock and at 1 h after resuscitation,the renal hemodynamics was monitored by ultrasound and the venous blood was extracted to examine the renal functions.The heart rate and arterial blood pressure were monitored throughout the experiment.Results The rabbits in both groups showed a significantly lower renal artery blood flow velocity during the shock（P0.05） with significantly increased pulsatility index（PI） and resistance index（RI） compared with those before the shock.One hour after resuscitation,the blood flow velocity in the renal arteries at all levels and the tertiary veins were reduced in NS group without obvious reduction of the PI and RI;in PEO group,the blood flow velocities in the renal arteries increased significantly compared to those before shock（P0.05）,and the PI and RI of the tertiary arteries were significantly lower than those in NS group（P0.05）.In both groups,BUN and Cr increased during endotoxin shock stage,and 1 h after resuscitation,PEO group showed significantly lower BUN and Cr levels than NS group（P0.05）.Conclusion A small dose of PEO can significantly promote renal perfusion in rabbits with septic shock,thus offering renoprotective effect against early damage in septicopyemia and septic shock.