全流量体外循环对SD大鼠肾小球滤过率的影响

Effect of full-flow cardiopulmonary bypass on glomerular filtration rate in SD rats

目的 建立体外循环致急性肾损伤（AKI）模型，研究全流量体外循环对SD大鼠肾小球滤过率（GFR）的影响。 方法 选取20只雄性SD大鼠，根据随机数字表法平均 分为体外循环组及假体外循环组。体外循环组大鼠麻醉诱导后行经口气管内插管，接呼吸机进行机械通气；于腹侧尾动脉及右侧颈静脉穿刺置管，建立体外循环灌注和引流通道。 体外循环管道包括静脉贮血器、蠕动泵、流量探测器及膜氧合器。体外循环流量维持在大鼠正常心输出量水平［160～180 ml/（kg·min）］，动脉灌注温度控制在34～36 ℃，术中 监测体温、血压及血气，体外循环持续时间为120 min。记录大鼠体外循环术前和术后2、7 d血、尿肌酐水平及GFR。假体外循环组大鼠只进行动静脉穿刺置管和管道连接，不进行 体外循环；指标监测和记录时点与体外循环组相同。记录2组大鼠术后7 d存活率。 结果 大鼠术后7 d存活率均为100%。术后2 d，体外循环组大鼠血、尿肌酐水平均明显高于 假体外循环组，GFR明显低于假体外循环组［（395±154）μmol/L比（188±70）μmol/L、（8.2±2.9）mmol/L比（5.2±1.9）mmol/L、（0.92±0.26）ml/（min·100 g）比（1.19 ±0.25）ml/（min·100 g）］（P＜0.05）；体外循环组术后2 d血肌酐水平明显高于术前［（291±68）μmol/L］（P＜0.05），术后7 d血、尿肌酐水平及GFR均基本恢复术前水平 。 结论 本研究成功建立了SD大鼠全流量体外循环致AKI模型，证明体外循环可导致大鼠GFR明显下降。

Objective To establish acute kidney injury（AKI） model induced by full-flow cardiopulmonary bypass（CPB） in rats; to analyze the effect of CPB on glomerular filtration rate（GFR）. Methods Totally 20 male SD rats were randomly and equally divided into CPB group and sham group. Operations in CPB group were as follows： anesthesia induction, endotracheal intubation and mechanical ventilation; puncturing and catheterizing at ventral caudal artery and right jugular vein as channels for CPB perfusion and drainage. CPB channel included a venous reservoir, a peristaltic pump, a flow probe and a membrane oxygenator. CPB flow was maintained at 160-180 ml/（kg·min）, CPB temperature was controlled at 34-36 ℃; body temperature, blood pressure and blood gas were monitored during CPB; the operation lasted for 120 min. Blood creatinine, urine creatinine and GFR were tested before CPB and 2 d, 7 d after operation. The sham group was treated with endotracheal intubation, arteriovenous puncture and catheterization, without CPB; blood creatinine, urine creatinine and GFR were tested at the same time as CPB group. Survival rates were recorded 7 d after CPB. Results All rats survived 7 d after CPB. Blood creatinine and urine creatinine in CPB group were significantly higher than those in sham group 2 d after operation, GFR in CPB group was significantly lower than that in sham group[（395±154）μmol/L vs （188±70）μmol/L, （8.2±2.9）mmol/L vs （5.2±1.9）mmol/L, （0.92±0.26）ml/（min·100 g） vs （1.19±0.25）ml/（min· 100 g）]（P〈0.05）. In CPB group, blood creatinine 2 d after CPB was significantly higher than that before operation[（291±68）μmol/L]（P〈0.05）; blood creatinine, urine creatinine and GFR recovered to preoperative levels 7 d after operation. Conclusion Full-flow CPB can cause significant decrease of GFR in SD rats.