The use of granisetron on bupivacaine induced sciatic nerve block in rats

PurposeThe effects of the 5-hydroxytryptamine (5-HT3) receptor antagonists on regional anaesthesia are complex and unclear. The present study was designed to test the hypothesis that granisetron, a selective 5-HT3 receptor antagonist, would decrease the duration of motor block, sensory block, and proprioception in a dose-dependent fashion in a rat model of bupivacaine-induced sciatic nerve blockade.Materials and methodsThirty-eight male Wistar Albino rats that received unilateral sciatic nerve blocks were randomly divided into five experimental groups. Group B received a perineural of 0.3 ml of bupivacaine alone; Group BG800 received perineural 0.3 ml of bupivacaine and 800 mu g of granisetron 10 min later; Group BG1200 received perineural 0.3 ml of bupivacaine and 1200 mu g of granisetron 10 min later; Group BG1200IP received a perineural 0.3 ml of bupivacaine and an intraperitoneal injection of 1200 mu g of granisetron 10 min later; and Group S was sham operated. A blinded investigator assessed motor, sensory and proprioception function every 10 min until the return of normal function.ResultsThe medians for recovery times in Group B, Group BG800, Group BG1200, and Group BG1200IP were 105, 64, 85, and 120 min for motor function, respectively; 80, 64, 84, and 104 min for sensory function; 80, 63, 85, and 108 min were calculated for the proprioception function. The time to the return of normal motor, sensory, and proprioception function was not statistically significantly different between the groups (p > 0.05). Motor block did not develop in any of the rats in Group S.ConclusionsLocal and systemic application of granisetron was not significantly decrease the duration of bupivacaine induced motor, sensory, and proprioception block of sciatic nerve in rat.