Safety and efficacy of different administration order on paradoxical reactions following midazolam in children: a randomised, controlled trial

Study Objective Midazolam is commonly used for Anesthesia induction. However, the paradoxical reactions increase risk of self-injury and bring pressure on anesthesiologist. Although various drugs have been showed effective, but the potential adverse effects limit the application. We compared safety and efficacy of different administration order on the occurrence of paradoxical reactions in children.Design Prospective, randomized, double-blinded study.Setting Operating room of a university-affiliated hospital.Patients 1306 ASA physical status I pediatric patients, aged 6 months to 12 years, scheduled for general anesthesia.Interventions Patients were divided into three groups. In the fentanyl group, patients were given fentanyl followed by midazolam at induction; In the midazolam group patients received midazolam followed by fentanyl at induction; In the blank group, patients were given saline followed by fentanyl at induction. Propofol was administrated 2.5 mg/kg intravenously (IV).Measurements Onset of paradoxical reactions and BIS values were observed and recorded.Main Results Preferentially and slowly injecting fentanyl could decrease the incidence of paradoxical reaction (p<0.05). Children displaying paradoxical reactions were mostly aged 8 months-2 years old (p = 0.001). Bispectralindex values increased significantly when paradoxical reactions burst out (p< 0.05). There were no significant differences in terms of side-effects.Conclusion Changing the administration order was safe and effective to decrease the incidence of paradoxical reactions.