A comparison of the onset time, duration of action, and fade characteristics of atracurium and vecuronium.
The speed of onset (T1 = 95% twitch depression) and the duration of action (T1 = 25% control) of equipotent doses of atracurium 0.5 mg/kg and vecuronium 0.1 mg/kg were compared in 21 ASA physical status I and II adult patients. Train-of-four (TOF) ratios (height of T4/T1) were also compared with the first response in the TOF recovered to 25% and 50% control, respectively. Neuromuscular function was measured by the Datex NMT 221 electromyograph at the hypothenar muscles. No significant difference was seen in the onset of action of these two drugs, but a significantly shorter duration of action was observed with vecuronium (P < 0.5). Vecuronium was also found to exhibit significantly more TOF fade on offset of block than atracurium. Vecuronium may offer a distinct advantage over atracurium when a nondepolarizer is required for a relatively short clinical case. However, it appears that vecuronium causes more TOF fade during recovery from neuromuscular blockade than atracurium.
Haines
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D000293:Adolescent; D000328:Adult; D001279:Atracurium / Q000494:pharmacology*; D004576:Electromyography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009469:Neuromuscular Junction / Q000187:drug effects*; D013997:Time Factors; D014673:Vecuronium Bromide / Q000494:pharmacology*
D001279:Atracurium; D014673:Vecuronium Bromide