Vecuronium bromide

Abstract: Background: Residual neuromuscular blockade remains a problem even after short surgical procedures. The train-of-four (TOF) ratio at the adductor pollicis required to avoid residual paralysis is now considered to be at least 0.9. The incidence of residual paralysis using this new threshold is not known, especially after a single intubating dose of intermediate-duration nondepolarizing relaxant. Therefore, the aim of the study was to determine the incidence of residual paralysis in the postanesthesia care unit after a single intubating dose of twice the ED95 of a nondepolarizing muscle relaxant with an intermediate duration of action. Methods: Five hundred twenty-six patients were enrolled. They received a single dose of vecuronium, rocuronium, or atracurium to facilitate tracheal intubation and received no more relaxant thereafter. Neuromuscular blockade was not reversed at the end of the procedure. On arrival in the postanesthesia care unit, the TOF ratio was measured at the adductor pollicis, using acceleromyography. Head lift, tongue depressor test, and manual assessment of TOF and DBS fade were also performed. The time delay between the injection of muscle relaxant and quantitative measurement of neuromuscular blockade was calculated from computerized anesthetic records. Results: The TOF ratios less than 0.7 and 0.9 were observed in 16% and 45% of the patients, respectively. Two hundred thirtynine patients were teste d2ho rmore after the administration of the muscle relaxant. Ten percent of these patients had a TOF ratio less than 0.7, and 37% had a TOF ratio less than 0.9. Clinical tests (head lift and tongue depressor) and manual assessment of fade showed a poor sensitivity (11–14%) to detect residual blockade (TOF < 0.9). Conclusion: After a single dose of intermediate-duration muscle relaxant and no reversal, residual paralysis is common, even more than 2 h after the administration of muscle relaxant. Quantitative measurement of neuromuscular transmission is the only recommended method to diagnose residual block.

Abstract: BackgroundSuccinylcholine has been the agent of choice when clinical conditions require emergency airway protection during a rapid-sequence induction of anesthesia. Rocuronium, a new nondepolarizing muscle relaxant with a brief onset of action, but devoid of the adverse reactions associated with suc

Abstract: BACKGROUND: Functional characteristics of the pharynx and upper esophagus, including aspiration episodes, were investigated in 14 awake volunteers during various levels of partial neuromuscular block Pharyngeal function was evaluated using videoradiography and computerized pharyngeal manometry during contrast bolus swallowing METHODS: Measurements of pharyngeal constrictor muscle function (contraction amplitude, duration, and slope), upper esophageal sphincter muscle resting tone, muscle coordination, bolus transit time, and aspiration under fluoroscopic control (laryngeal or tracheal penetration) were made before (control measurements) and during a vecuronium-induced partial neuromuscular paralysis, at fixed intervals of mechanical adductor pollicis muscle train-of-four (TOF) fade; that is, at TOF ratios of 060, 070, 080, and after recovery to a TOF ratio > 090 RESULTS: Six volunteers aspirated (laryngeal penetration) at a TOF ratio 090 or during control recording Pharyngeal constrictor muscle function was not affected at any level of paralysis The upper esophageal sphincter resting tone was significantly reduced at TOF ratios of 060, 070, and 080 (P 090 is reached The upper esophageal sphincter muscle is more sensitive to vecuronium than is the pharyngeal constrictor muscle

Abstract: We have investigated residual block after anaesthesia which included the use of the neuromuscular blocking agent vecuronium but no anticholinesterase, in 568 consecutive patients on admission to the recovery room. The ulnar nerve was stimulated submaximally using TOF stimulation (30 mA). Postoperative residual curarization was defined as a TOF ratio