[Rocuronium, the "ideal" nondepolarizing muscle relaxant?]

Rocuronium bromide (Org 9426) is a new, non-depolarising steroidal muscle relaxant that is currently undergoing extensive clinical trials worldwide. Since it is expected to be introduced into clinical practice in the near future, the purpose of this review is to give a summary of the currently available information on this promising new compound. The search for the so-called ideal muscle relaxant [34] in the last years was focused on a non-depolarising compound that could replace succinylcholine for rapid intubation. The currently most frequently used agents vecuronium and atracurium have an onset of action that usually does not allow intubation earlier than 3 min after its injection. Recent animal [40] and human [10] studies have shown that development of neuromuscular blockade of the vocal cords and laryngeal muscles can be faster than that of the peripheral skeletal muscles. This would mean that intubation can be performed before complete relaxation of the adductor muscle of the thumb is achieved. Rocuronium is the 2-morpholino, 16 N-allyl-pyrrolidino derivative of the 3-hydroxy metabolite of vecuronium. In initial clinical studies [13, 42] its most impressive features appeared to be rapid onset time and, more importantly, the rapid development of good intubating conditions. Thirty to 90 s after the injection of 0.6 mg/kg (2 x ED90), rocuronium provided intubating conditions that were equal to those observed after succinylcholine [9, 17, 31, 38]. Although the onset time of rocuronium at the adductor pollicis muscle is slower than that of succinylcholine, intubation with this compound can be performed faster than with any other non-depolarising agent.(ABSTRACT TRUNCATED AT 250 WORDS)