The effects of sevoflurane are similar to those of isoflurane on the neuromuscular block produced by vecuronium.
We have examined the interactions of 1 MAC of isoflurane and sevoflurane (and 66% nitrous oxide in oxygen) with vecuronium, using the EMG response of the abductor digiti minimi to train-of-four (TOF) stimulation of the ulnar nerve. We constructed dose-response curves for vecuronium in 54 patients. The curves for both isoflurane and sevoflurane had a significant leftward shift compared with that for fentanyl-nitrous oxide anaesthesia (P < 0.01). When the amplitudes of the first response (T1) had recovered to 50% of control in another 32 patients, subsequently we compared the spontaneous recovery rate of the ratio of the fourth to the first TOF response (T4:T1) at 3-min intervals during the 15-min period, in the presence of two volatile anaesthetics or after discontinuation of administration of anaesthetic. The rate of recovery of T4:T1 was significantly greater when both anaesthetics were discontinued. However, this rate was similar for both anaesthetics, suggesting that the mechanism of action of the two anaesthetics is similar.
Morita
T
T
Department of Anaesthesiology and Reanimatology, Gunma University School of Medicine and Hospital, Japan.
Tsukagoshi
H
H
Sugaya
T
T
Yoshikawa
D
D
Fujita
T
T
D000328:Adult; D000768:Anesthesia, General; D000777:Anesthetics; D004305:Dose-Response Relationship, Drug; D004347:Drug Interactions; D004558:Electric Stimulation; D004576:Electromyography; D004987:Ethers; D006801:Humans; D007530:Isoflurane; D008738:Methyl Ethers; D008875:Middle Aged; D009407:Nerve Block; D009469:Neuromuscular Junction / Q000187:drug effects*; D000077149:Sevoflurane; D013997:Time Factors; D014673:Vecuronium Bromide
D000777:Anesthetics; D004987:Ethers; D008738:Methyl Ethers; D000077149:Sevoflurane; D014673:Vecuronium Bromide; D007530:Isoflurane