A comparison of the effect of rocuronium and vecuronium on heart rate during gynaecological laparoscopy

The effect on intra-operative heart rate of two nondepolarising muscle relaxants, rocuronium and vecuronium, was compared in 116 fit out-patients undergoing gynaecological laparoscopic procedures. Both groups received an anaesthetic technique which differed only in the choice of muscle relaxant. Intra-operatively it was noted that patients given rocuronium (20 mg) had significantly fewer episodes of bradycardia (heart rate < 50 beat.min-1) than patients given vecuronium 4 mg (p < 0.05). Profound bradycardias (heart rate < 30 beat.min-1) did not occur in any of the patients in the rocuronium study group, whereas 5% of patients receiving vecuronium had a period of transient asystole. We conclude that, at the doses stated, rocuronium results in significantly fewer episodes of bradycardia than vecuronium when used as a muscle relaxant for laparoscopic gynaecological procedures.