婴幼儿活体肝移植术中罗库溴铵持续输注的药效学研究

Study on pharmacodynamics of continuous infusion of rocuronium during transplantation of living donor liver for infants

目的观察婴幼儿肝移植术中罗库溴铵持续输注的药效学研究。方法选择14例活体肝移植术受体患儿作为研究对象,年龄6个月～2岁,体质量5～10 kg,Child-Push评分7～10分,肝功能分级B级或C级,ASAⅢ或Ⅳ级。采用4个成串刺激（TOF）模式进行肌松监测,麻醉诱导给予罗库溴铵0.6 mg/kg,T1达到最大抑制时行气管插管。当T1恢复到3%时,开始输注罗库溴铵5μg/（kg/min）,调节静脉输注速度,使T1维持在3%～10%,于缝合腹膜后停止使用肌松药。记录麻醉诱导后肌松起效时间、TOF无反应期、停药后T1恢复至25%时间、恢复指数以及肝移植术中3个间期的罗库溴铵平均输注速率。结果罗库溴铵首剂量诱导的起效时间为（82.86±14.77）s,TOF无反应期（45.80±16.88）min,T1恢复至25%时间为（18.98±8.57）min,恢复指数为（37.05±7.95）min。维持恒定肌松抑制程度,平均输注速率：无肝前期为（2.80±0.96）μg/（kg/min）,无肝期为（1.81±0.34）μg/（kg/min）,新肝期为（2.54±0.98）μg/（kg/min）;与无肝前期比较,无肝期罗库溴铵的需要量下降了35%（P〈0.05）,新肝期基本保持不变。结论在婴幼儿肝移植术中,罗库溴铵在无肝期的平均用量较无肝前期降低,新肝期较无肝前期基本保持不变。在婴幼儿肝移植术中,应充分认识肌松药的药效学特征;使用罗库溴铵麻醉诱导时,应在用药1.5 min后进行气管插管,无肝期适当减少药物用量,避免发生神经肌肉阻滞作用延长。

Objective To explore the pharmacodynamics of continuous infusion of rocuronium during the liver transplantation for infants. Methods Fourteen patients who underwent transplantation of living donor liver were selected. Patients were 6 months to 2 years old. Their body weights were 5 -10 kg. The scores of Child- Push were 7 - 10; the classifications of hepatic function were B or C; and their ASA were Ⅲ or Ⅳ. The responses of the adductor pollicis muscle to train-of-four （TOF） stimulation of ulnar nerve were monitored. Rocuronium of 0.6 mg/kg was given during induction. Tracheal intubation was performed when 100% blockade was attained and mechanical ventilation was instituted. When T1 recovered to 3%, rocuronium was infused at an initial infusion rate of 5μg/kg/rain. The infusion rate was adjusted to maintain T1 at 3%-10%. The administration of muscle relaxant was stopped after the suture of the peritoneum. The onset time, TOF no reaction period, the time for the recovery of T1 to 25%, recovery index, and average infusion rates of rocuronium at three stage were recorded. Results The onset time of rocuronium was （82.86 ＋14. 77） s; the TOF no reaction period was （45.80 ＋16.88） rain; the time for the recovery ofT1 to 250/0 was （18.98＋8. 57） rain; and the recovery time was （37.05 ＋7.95） rain. The muscle inhibition was maintained constant and the infusion rate was （2.80 ＋ 0.96） lag/（kg/rain） before the anhepatic phase, （ 1.81 ＋ 0.34） pg/（kg/rain） during the anhepatic phase, and （2.54 ＋ 0.98） pg/（kg/min） after reperfusion. Compared to the requirement of rocuronium before the anhepatic phase, the requirement of rocuronium after the anhepatic phase decreased 35% （P〈0.05） and the requirement of rocuronium during the anhepatic phase remained the same. Conclusion During the liver transplantation for infants, the average dose of rocuronium after the anhepatic phase is lower than that before the anhepatic phase and the average dose of rocuronium during the anhepatic phase is the same as that before the anhepatic phase. The pharmacodynamics characteristics of muscle relaxants during liver transplantation should be fully understood. When rocuronium is administrated to induce, tracheal intubation should be performed 1.5 rain after the administration of rocuronium. The drug dosage should be appropriately reduced during the anhepatic stage to avoid prolonging the neuromuscular blockade.