Efficacy of low-dose rocuronium in reducing induction dose of propofol in classic laryngeal mask airway insertion in one day case surgery

Background The amount of sedation and muscle relaxation of the jaw may affect complications caused by laryngeal mask airway (LMA). The aim of this study is to evaluate the effect of low-dose rocuronium on reducing the induction dose of propofol needed for LMA insertion in patients undergoing one day case surgery and its effect on LMA insertion conditions and complications.Patients and methods Sixty patients were included in this randomized double-blind clinical study. Patients were divided into two groups: the control group (group I) received intravenous fentanyl 1 μg/kg and midazolam 0.05 mg/kg, 5 ml normal saline (placebo) and propofol (n=30). The second (study) group (group II) receive intravenous fentanyl 1 μg/kg and midazolam 0.05 mg/kg, 0.15 mg/kg rocuronium diluted in 5 ml normal saline and propofol (n=30). Propofol dose was adjusted by loss of movements to maximum jaw thrust. Demographic data, American Society of Anesthesiologist physical status, duration of surgery, duration of anesthesia, systolic and diastolic blood pressures, heart rate measurements (basal readings were recorded as well as immediately after induction then after 1 min till the fifth minute), induction dose of propofol, success rate of LMA insertion from the first time, speed of insertion, and any complications were recorded.Results There were no significant differences between both groups regarding demographic data, American Society of Anesthesiologist physical status, duration of surgery, duration of anesthesia, heart rate, success rate of insertion from the first time and complications. On the contrary, there were significant statistical differences between both groups regarding induction dose of propofol (P<0.0001). Both systolic and diastolic blood pressures were noticeably lower in group I than that in group II immediately after induction (P=0.026 and 0.017, respectively). Moreover, the time of LMA insertion was significantly lower in group II (P<0.0001).Conclusion Using low-dose rocuronium (0.15 mg/kg) increases jaw relaxation, reduces propofol requirements in induction for LMA insertion, decreases the time needed for its insertion, and relatively decreases postoperative complications related to LMA insertion.