Remifentanil Prevents Withdrawal Movements Caused by Intravenous Injection of Rocuronium

PURPOSE: The incidence of pain induced withdrawal movement following intravenous injection of rocuronium is high. This randomized, double-blind, placebo-controlled study was designed to evaluate the effect of pretreatment of remifentanil on the withdrawal movements due to intravenous injection of rocuronium during anesthetic induction. MATERIALS AND METHODS: Ninety adult female patients undergoing thyroidectomy were randomly allocated to three groups. Each patient intravenously received one of three solutions of equal volume (4 mL): normal saline (Group I, n = 30), 0.5 µg/kg remifentanil (Group II, n = 30) or 1 µg/kg remifentanil (Group III, n = 30). Thirty seconds after remifentanil administration, anesthesia was induced with 5 mg/kg IV thiopental. Twenty seconds after thiopental injection, 0.6 mg/kg IV rocuronium was administered (injection rate of 0.5 mL/sec) and patients' withdrawal movements were assessed. Mean arterial pressure (MAP) and heart rate were assessed on arrival in the operation room, before the tracheal intubation and immediately, 1 and 2 min after the tracheal intubation. RESULTS: The incidence of withdrawal movements was significantly lower in both of the remifentanil groups (3 and 0% in Group II and III, respectively) than in the saline group (70%). Remifentanil attenuated the increase of heart rate and MAP immediately and 1 min after the tracheal intubation. CONCLUSION: The pretreatment with 0.5 and 1.0 µg/kg remifentanil of bolus doses prevented the withdrawal movements caused by rocuronium injection, and effectively blunted cardiovascular activation following tracheal intubation.