Intranasal dexmedetomidine premedication reduces minimum alveolar concentration of sevoflurane for laryngeal mask airway insertion and emergence delirium in children: a prospective, randomized, double-blind, placebo-controlled trial

Abstract

Background: We conducted a prospective, randomized, double-blind, placebo-controlled study to verify the hypothesis that intranasal dexmedetomidine premedication can reduce the minimum alveolar concentration of sevoflurane for laryngeal mask airway insertion in children.

Methods: Ninety American Society of Anesthesiologists (ASA) physical status I subjects, aged 3-7 years, were randomized to three equal groups to receive saline (Group S), dexmedetomidine 1 μg · kg(-1) (Group D1 ), or dexmedetomidine 2 μg · kg(-1) (Group D2 ) approximately 45 min before anesthesia. The minimum alveolar concentration for laryngeal mask airway insertion of sevoflurane was determined according to the Dixon's up-and-down method. Emergence delirium was evaluated using the Pediatric Anesthesia Emergence Delirium (PAED) scale in the postanesthesia care unit (PACU).

Results: Dexmedetomidine premedication of 1 and 2 μg · kg(-1) was associated with reduction in sevoflurane from 1.92% to 1.53% and 1.23%, corresponding to decrease of 20% and 36%, respectively. The peak PAED scores (median [IQR]) were 9 [8-11.5], 5 [3-5.3], and 3 [2-4] in Group S, Group D1, and Group D2 , respectively. The incidence of emergence delirium (defined as peak PAED score ≥ 10) was significantly lower in Groups D1 and D2 than in Group S (P < 0.001). Simultaneously, the induction qualities and the parent's satisfaction scores were significantly higher in Groups D1 and D2 than in Group S (P < 0.001).

Conclusion: Intranasal dexmedetomidine premedication produces a dose-dependent decrease in the minimum alveolar concentration for laryngeal mask airway insertion of sevoflurane and emergence delirium in the PACU.

Keywords: child; depth of anesthesia; emergence delirium; inhaled agents; postanesthesia care unit.