Prevention of Emergence Delirium in Children – A Randomized Study Comparing Two Different Timings of Administration of Midazolam

BACKGROUND: Emergence delirium (ED) is a distressing side effect of sevoflurane anesthesia in children. Midazolam is a widely studied drug for the prevention of ED with conflicting results. AIM, SETTINGS AND DESIGN: We designed this prospective randomized double-blind study to compare the effect of 0.03 mg/kg midazolam administered at induction and the same dose administered 10 min before the end of surgery in the prevention of ED in children undergoing sevoflurane anesthesia and also the effect on the time to recovery in both groups. MATERIALS AND METHODS: Eighty children between 2 and 8 years belonging to patient physical status American Society of Anesthesiologist Classes 1 and 2 undergoing infra-umbilical surgeries under general anesthesia were randomly allocated to receive 0.03 mg/kg midazolam at induction (Group A) and 10 min before the end of surgery (Group B). Caudal block was administered for analgesia after induction. The primary outcome, the incidence of ED was evaluated using the Paediatric Anaesthesia Emergence Delirium Scale from the time of extubation till 30 min postsurgery. The secondary outcome measured was the time to recovery (time from discontinuation of sevoflurane to the time of extubation) and the results were statistically analyzed. RESULTS: The incidence of ED was comparable between the groups (30%, 10%, 5%, and 2.5% at 5, 10, 15, and 20 min, respectively in Group A and 25%, 10%, 5%, and 2.5% of children at 5, 10, 15, and 20 min, respectively in Group B). Recovery was significantly prolonged in Group B (42.5% of patients in Group A recovered within 6 min of discontinuation of sevoflurane in Group A compared to only 20% of patients in Group B). CONCLUSION: There is no difference in the reduction of incidence of ED following sevoflurane anesthesia when midazolam is administered at induction or the end of surgery. However, the time to recovery was longer when the drug was administered at the end of the surgery.