脂肪乳联合不同剂量肾上腺素在救治布比卡因致兔心脏毒性中的作用

目的比较脂肪乳联合不同剂量肾上腺素救治布比卡因所致兔心脏毒性的作用效果。方法健康成年的新西兰大白兔35只,随机分为5组、每组7只：脂肪乳组（L组）、生理盐水组（C组）,脂肪乳联合肾上腺素5、25、50μg·kg^-1组（L5、L25、L50）,耳缘静脉留置套管针建立静脉通路,气管切开后行机械通气,颈动脉置管监测有创动脉压。有创操作完成后,稳定30min,标记为T0时间点,采动脉血行血气分析后持续泵注布比卡因1.5mg·（kg·min）^-1直到兔心率〈60次·min^-1同时伴平均动脉压〈20mmHg,达到标准并维持10s后开始行心肺复苏。L组给予20%脂肪乳注射液3mL·kg^-1,并以0.5 mL·（kg·min）^-1持续泵注,L5、L25、L50组给予上述剂量脂肪乳后再分别给予肾上腺素5、25、50μg·kg^-1单次静脉注射。C组仅给予生理盐水3mL·kg^-1后以0.5 mL·（kg·min）^-1持续泵注。持续监测心电图和有创动脉血压。记录在心肺复苏开始后第5、10、15、20min时（记为T1、T2、T3、T4时间点）恢复自主循环的动物数量。结果 T1时,L5组、L25组、L50组MAP值高于C组和L组（P〈0.05）,L25组、L50组MAP值高于L5组,L50组高于L25组（P均〈0.05）;T2时,C组低于其余4组,L25组高于L5组（P均〈0.05）;T3和T4时,L组、L5组、L25组MAP值高于C组（P均〈0.05）;T4时,L25组高于L50组（P〈0.05）。T1时,L25组和L50组HR值高于C组、L组、L5组（P均〈0.05）;T2时,L25组和L50组HR值高于C组（P均〈0.05）;T3和T4时,L组、L5组、L25组、L50组HR值高于C组（P均〈0.05）;T4时,L25组高于L50组（P〈0.05）。QRS间期、PR间期在T4时,C组均高于其他四组（P均〈0.05）;T4时的C组、L组、L50组均高于T0基础值（P均〈0.05）。T4时,各组恢复自主循环的动物数量分别为C组0只、L组2只、L5组3只、L25组5只、L50组1只。结论在本模型下,脂肪乳剂联合25μg·kg^-1肾上腺素在救治布比卡因所致新西兰大白兔心脏?

A Comparison of Lipid Emulsion Combined with Epinephrine in Resuscitating the Cardiotoxicity after Intravenous Injection of Bupivacaine in Rabbits

Objective To assess the effect of lipid emulsion combined with epinephrine of three different do- ses to resuscitate the cardiovascular collapse induced by continuous bupivacaine intravenous infusion. Meth- ods 35 pentobarbital -anesthetized rabbits were given endotracheal intubation and mechanical ventilation （100% oxygen）. After a 30 minutes stabilization period,bupivacaine was administered at a rate of 1.5 mg· （kg· min）^-1 until the heart rate decreased to 60 beats/min and the mean blood pressure were below to 20mmHg. Once reached the point and maintained 10s, external chest compressions were started immediately. At 1 minute, rabbits in group L, 16, L25,160 （ n = 7） received 3mL · kg^-1 20% intralipid and followed by a continuously infused at the rate of 0.5 mL · （kg · min）^-1. Additionally, rabbits in the group L5, L25, LS0 were infused epinephrine 5,25,50μg · kg^-1 respectively. Rabbits in the group C （ n = 7） received 3mL · kg^-1 0.9% saline and followed by a continuously infused at the rate of 0.5 mL · （kg · min）^-1. The ECG and ar- terial pressure were continuously monitored to 20 minutes. Results Mean blood pressure at T1 , in group L5, L25,L50 were significantly higher than that in group C, L （ P 〈 0.05 ）. Mean blood pressure at T1 in group I225,160 were significantly higher than that in group LS. Mean blood pressure at T1 in group I50 was signifi- cantly higher than that in group L25 （P 〈 0.05 ）. MAP at T2, in group C was significantly lower than that in other four groups . MAP at T2, in group L25 was significantly higher than that in group 16 （ P 〈 0.05 ）. MAP at T2,in group L, LS, L25 were significantly higher than that in group C at T3,T, （P 〈 0.05 ）. MAP at T4, in group L25 was significantly higher than that in group 160 （ P 〈 0.05）. HR in group C, L, L5 were significantly lower than that in group/_25 and group LS0 at T1 （P 〈 0.05 ）. HR at T2, group L25, LS0 were significantly lon- ger than that in group C （ P 〈 0.05）.