Low and high frequency stimulation tests to characterize the effects of edrophonium on vecuronium-induced neuromuscular block.
We recorded adductor pollicis mechanical activity in response to low (0.1 and 2 Hz) and high (50 and 100 Hz) frequency stimulation 15 min after edrophonium 250, 500 and 1000 micrograms kg-1, given to antagonize vecuronium-induced block at 10, 25 and 50% pre-reversal twitch height. We studied 54 ASA class I and II anaesthetized (methohexitone, fentanyl, nitrous oxide) young adult patients allocated randomly to nine groups of six patients each. The greater sensitivity of train-of four (TOF) ratio and residual force after 100-Hz, 5-s tetanic stimulation (RF100) to residual deficit allowed discrimination more readily between the effects of edrophonium dose and pre-reversal twitch height (P < 0.001, two-way analysis of variance). The highest reversal scores (approximately 0.9 TOF ratio and 0.6 RF100) were obtained when edrophonium 500-1000 mg kg-1 was given at 50% twitch height (P < 0.05, Duncan's test).
Baurain
M J
MJ
Department of Anaesthesiology, University Hospital Erasme, Brussels, Belgium.
Dernovoi
B S
BS
d'Hollander
A A
AA
Hennart
D A
DA
Cantraine
F R
FR
D000293:Adolescent; D000328:Adult; D004305:Dose-Response Relationship, Drug; D004491:Edrophonium / Q000494:pharmacology*; D006801:Humans; D008875:Middle Aged; D009119:Muscle Contraction / Q000187:drug effects / Q000502:physiology; D009407:Nerve Block; D009469:Neuromuscular Junction / Q000187:drug effects* / Q000502:physiology; D009435:Synaptic Transmission; D004561:Transcutaneous Electric Nerve Stimulation; D014673:Vecuronium Bromide / Q000037:antagonists & inhibitors*
D004491:Edrophonium; D014673:Vecuronium Bromide