RESUMEN
Pruritus is a common adverse event of intrathecal fentanyl for postoperative analgesia. Activation of central 5-hydroxytryptamine subtype[3] [5-HT [3]] receptors is one of its possible mechanisms. This randomized, double-blind, placebo-controlled study aimed at evaluating the effectiveness of granisetron for the prevention of intrathecal fentanyl-induced pruritus in patients undergoing gynecologic, urologic, orthopedic and general surgery. 120 parturients [American Society of Anesthesiologists [ASA] I-II status] undergoing surgery under spinal anesthesia using 15 mg hyperbaric bupivacaine [0.5%] and 25 micro g fentanyl were randomly divided to three equal groups [n=40]. Thirty minutes before spinal anesthesia, patients received granisetron 1 mg IV [GRN], granisetron 1 mg plus 8 mg dexamethasone IV [GRN/DEX], or normal saline IV [Placebo]. Pruritus, pain, sedation, nausea and vomiting scores were evaluated during the initial 24 hours postoperatively. The incidence of pruritus was significantly more frequent in Placebo group compared with GRN and GRN/DEX groups [75% versus 50% and 45%] [P