Do metoclopramide and ondansetrone alter mivacurium-induced neuromuscular blockade? - a randomised trial.

BACKGROUND We aimed to investigate the effects of metoclopramide and ondansetrone on mivacurium neuromuscular blockade. METHODS Seventy five, ASA I-II patients, aged 18-65 and scheduled for elective surgery requiring tracheal intubation were included in the study. The patients received metoclopramide 10 mg, ondansetrone 4 mg or normal saline 5 mL; group M, group O, group NS (n=25), respectively. Before anesthesia study drugs were administered in a volume of 5 mL. The level of plasma cholinesterase were obtained before and 5 minutes after the administration of study drugs and 5 minutes after the administration of mivacurium. Onset time, T25, T75, T25-75, T90 levels were compared with each other and differences between each patients were investigated. After recording T90, the study was terminated and surgery was started. RESULTS Onset time was significantly shorter in group M, than the other two groups. Onset time in group O was significantly shorter than in group NS. In Group M T25, T75, T90 and recovery indices were significantly greater than in Group NS (p<0.001). In Group O T25, T75 were greater than Group NS (p<0.01 and p<0.05, respectively). In Group M T75, T90 and emergence indices were significantly higher than Group O (p<0.001, p<0.01, p<0.001, respectively). In Groups M and O, plasma cholinesterase levels decreased significantly (p<0.001) after administration of study drugs and mivacurium. Plasma cholinesterase also was reduced in Group NS 5 minutes after the administration of mivacurium (p<0.001). CONCLUSION Ondansetrone is believed to be more reliable agent than metoclopramide when used with mivacurium.