Many trials have been conducted on the prevention of pain induced by intravenous rocuronium. The aim of this study was to assess the effectiveness of lidocaine preinjection compared with rocuronium premixed with lidocaine in minimizing pain on injection.

Seventy five patients, ASA physical status I or II, were randomly allocated to one of three groups. In the control group (n = 25), patients received saline 3 ml, followed 20 slater by rocuronium (0.6 mg/kg) only. In the lidocaine premixture group (PM, n = 25), normal saline 3 ml and rocuronium(0.6 mg/kg) premixed with lidocaine 30 mg were given intravenously, and in the lidocaine preinjection group (PI, n = 25), lidocaine 30 mg was administered before injection of rocuronium (0.6 mg/kg). Pain was assessed verbally as none, mild, moderate, and severe by the same observer.

There was a significant reduction in the incidence and severity of pain in the PI group. Only 6 patients (24%) in the PI group experienced pain as compared to 16 patients (64%) in the PM group and 22 patients (88%) in the control group.

Lidocaine 30 mg given before the administration of rocuronium significantly reduced the incidence and severity of rocuronium induced pain. But, lidocaine rocuronium premixtures did not significantly reduce the incidence of pain.