Prevention of rocuronium-induced withdrawal movement in children: a comparison of remifentanil with alfentanil

BACKGROUND: This study was designed to compare the efficacy of remifentanil and alfentanil without the venous occlusion technique in preventing the withdrawal response associated with rocuronium injection in children. METHODS: One hundred and twenty children aged between 3 and 10 years were randomly allocated into one of four groups to receive either i.v. remifentanil 0.5 microg.kg(-1) (remi 0.5 group), remifentanil 1 microg.kg(-1) (remi 1.0 group), alfentanil 15 microg.kg(-1) (alfentanil group) or saline 5 ml (saline group). Anesthesia was induced with 2.5% thiopental sodium 5 mg.kg(-1) and the test drug was injected over 30 s. One minute later, 1% rocuronium 0.6 mg.kg(-1) was injected over 5 s and the response was recorded. Mean arterial pressure (MAP) and heart rate (HR) were recorded on arrival in the operating room, before and 1 min after tracheal intubation. RESULTS: The incidence of withdrawal movement in the saline group (93%) was significantly higher than that in the remi 0.5, remi 1.0, and alfentanil groups (53%, 17%, and 20%, respectively) (P < 0.05). The incidence in the remi 1.0 and alfentanil groups was significantly less than that in the remi 0.5 group (P < 0.05). After intubation, MAP and HR were significantly higher in the saline group than that in remi 1.0 and alfentanil groups. CONCLUSIONS: Both remifentanil 1 microg.kg(-1) and alfentanil 15 microg.kg(-1) can be used to prevent rocuronium-associated withdrawal movement in children because they are equally effective and attenuate the increase in MAP and HR after intubation.