The Effect of Dilution with 0.9% Normal Saline on Reducing Withdrawal Movement Induced by Rocuronium Injection

ABSTRACT

BACKGROUND: The intravenous injection of rocuronium after loss of consciousness during induction of general anesthesia can cause a withdrawal movement of hand, arm or more than one extremity. We designed this study to examine diluted rocuronium (2 mg/ml) with 0.9% normal saline can reduce withdrawal movement. METHODS: Eighty healthy female patients (aged 19-63) scheduled for general anesthesia were randomly assigned to one of two groups; Group 1 (rocuronium 10 mg/ml) and Group 2 (rocuronium diluted to 2 mg/ml with 0.9% normal saline). After loss of consciousness and eyelid reflex by intravenous injection of thiopental sodium 5 mg/kg, rocuronium (0.6 mg/kg) was injected at the speed of 1 ml/sec in both groups. The incidence and severity of withdrawal movements were assessed by using four-point scales. RESULTS: The incidence and severity of withdrawal movement in response to rocuronium injection were significantly reduced in Group 2 compared to Group 1 (P < 0.05). CONCLUSIONS: Dilution of rocuronium 10 mg/ml to 2 mg/ml with 0.9% normal saline was significantly effective for reducing withdrawal movement during induction of general anesthesia. This is a simple and effective strategy for preventing rocuronium-induced withdrawal movement.