ABSTRACT
Administration of a subparalytic dose of a nondepolarizing muscle relaxant prior to intubating dose hastens the onset time of neuromuscular blockade. This study was designed to investigate the influence of a priming dose of vecuronium (0.015 mg/kg) and d-tubocurarine (0.05 mg/kg) on intubating dose of vecuronium (0.085 mg/kg). The authors measured TOF ratio using neuromuscular monitoring. This monitoring was carried out by stimulation of ulnar nerve at a frequency of 2Hz every 20 seconds using Datex relaxograph to measure the compound evoked electrographic response of hypothenar muscle. The patients were randomly divided into two groups as priming dose ; vecuronium and dtubocurarine (DTC) group respectively. Mixture of two different nondepolarizing muscle relaxant may produce synergism, although the reason for this synergism is unknown. It may be the results of the action of the drugs at different sites. In our study, we found the results as follows ;1) The rapid onset was occured with d-tubocurarine(0.05 mg/kg) as priming drug than vecuronium (0.015 mg/kg) 2) The duration was longer when d-tubocurarine was used (P<0.05) The authors conclude that the onset is more rapid and the duration is longer when other species of nondepolarizing muscle relaxant is used than same agent is used as priming drug.