Midazolam does not reduce emergence delirium after sevoflurane anesthesia in children

Behavioral disturbance in children following sevoflurane anesthesia is a relatively frequent event. The aim of this study was to evaluate whether a higher dose of preoperatively administered rectal midazolam compared with a lower would alleviate this phenomenon. Furthermore the impact of these two doses of midazolam on sedation at induction of anesthesia was compared.A total of 115 children presenting for minor surgery under anesthesia were included in the study. The children were randomized to receive rectally either 1 mg.kg(-1) midazolam (group H) or 0.5 mg.kg(-1) midazolam (group L). General anesthesia was induced with propofol or sevoflurane and maintained with 1.5% sevoflurane in the inspiratory limb. Prior to the start of surgery a regional block was performed to ensure adequate pain relief. Behavior on emergence was assessed using a three point scale. In case of severe agitation propofol was administered IV.The children in group H were significantly better sedated preoperatively (P < 0.01). There was no significant difference in emergence behavior: 42.1% of children in group H compared with 36.2% of children in group L exhibited severe agitation requiring sedation with propofol (P = 0.37). However, regardless of the preoperative dose of midazolam more children under the age of 36 months (61.4%) were severely distressed at emergence compared with older children (16.7%) (P < 0.01).A higher dose of 1 mg.kg(-1) rectal midazolam results in much better sedated children on induction of anesthesia than 0.5 mg.kg(-1). This, however, does not result in a reduced incidence of emergence delirium after sevoflurane anesthesia. Regardless of the premedication negative behavioral changes occur more frequently in children younger than 3 years of age.