Antognini J F, Wood R, Gronert G A
Department of Anesthesiology, University of California, Davis 95616-8634, USA.
J Vet Pharmacol Ther. 1995 Dec;18(6):464-7. doi: 10.1111/j.1365-2885.1995.tb00627.x.
Non-depolarizing muscle relaxants can facilitate surgery and anaesthesia in numerous species. and volatile inhalational anaesthetics such as isoflurane potentiate their action. We studied the effect of isoflurane on the pharmacodynamics and pharmacokinetics of metocurine in six goats. Each was studied twice: once during barbiturate-opiate anaesthesia and once during isoflurane anaesthesia. The evoked response to sciatic nerve stimulation was measured using a force transducer attached to the hoof. Metocurine was infused until approximately 80-90% blockade. Plasma metocurine concentration was determined by high-performance liquid chromatography. Isoflurane increased the potency of metocurine significantly; IC50 (the concentration in the effect compartment at 50% paralysis) was 70 +/- 15 ng/mL during isoflurane anaesthesia and 129 +/- 42 ng/mL during barbiturate-opiate anaesthesia (P < 0.03). Volume of distribution (63 +/- 18 mL/kg), clearance (1.6 +/- 0.4 mL/min.kg) and elimination half-life (99 +/- 9 min) during barbiturate-opiate anaesthesia were not significantly different during isoflurane anaesthesia: 64 +/- 25 mL/kg, 1.5 +/- 0.7 mL/kg.min, 116 +/- 16 min respectively. We conclude that, relative to barbiturate-opiate anaesthesia, isoflurane potentiates metocurine in goats.
非去极化肌肉松弛剂可在众多物种中辅助手术和麻醉。而异氟烷等挥发性吸入麻醉剂会增强其作用。我们研究了异氟烷对6只山羊美托库铵药效学和药代动力学的影响。每只山羊均进行两次研究：一次在巴比妥类-阿片类麻醉期间，一次在异氟烷麻醉期间。使用连接到蹄部的力传感器测量坐骨神经刺激的诱发反应。输注美托库铵直至出现约80-90%的阻滞。通过高效液相色谱法测定血浆美托库铵浓度。异氟烷显著增强了美托库铵的效力；在异氟烷麻醉期间，IC50（产生50%麻痹时效应室中的浓度）为70±15 ng/mL，在巴比妥类-阿片类麻醉期间为129±42 ng/mL（P<0.03）。在巴比妥类-阿片类麻醉期间的分布容积（63±18 mL/kg）、清除率（1.6±0.4 mL/min·kg）和消除半衰期（99±9 min）在异氟烷麻醉期间无显著差异，分别为64±25 mL/kg、1.5±0.7 mL/kg·min、116±16 min。我们得出结论，相对于巴比妥类-阿片类麻醉，异氟烷在山羊中增强了美托库铵的作用。
