Sevoflurane-emergence agitation: effect of supplementary low-dose oral ketamine premedication in preschool children undergoing dental surgery

Abstract

The use of sevoflurane in paediatric anaesthesia which could enable rapid recovery is complicated by the frequent occurrence of emergence agitation. The aim of this study was to test the efficacy of supplementing midazolam-based oral premedication with low-dose oral ketamine in reducing sevoflurane-related emergence agitation. Ninety-two healthy preschool children who have been scheduled for elective dental procedures under general anaesthesia were allocated into two groups (46 patients for each): group M received oral midazolam 0.5 mg kg(-1), whereas group KM received similar premedication in addition to ketamine 2 mg kg(-1). Acceptance of drug mixture and onset of action were monitored over the next 30 min. Induction of anaesthesia was carried out using sevoflurane 8 vol% in 100% oxygen via face mask. Anaesthesia was maintained with sevoflurane 1.5-2 vol% in oxygen-nitrous oxide mixture. Following extubation, standard scoring scale was used for assessing quality of emergence. Agitation parameters were measured using a five-point scale. Agitated children were managed by giving intravenous increments of fentanyl 1 microg kg(-1). The time of hospital discharge allowance was recorded. Vast majority of children accepted the premedication. There were no significant differences between both groups regarding recovery from sevoflurane and allowance of hospital discharge. Onset of action of premedication was shorter in group KM. Similarly, postoperative agitation score and rescue fentanyl consumption were markedly lower in group KM upon admission to the postanaesthesia care unit (P<0.01). Adding a low dose of oral ketamine to midazolam-based oral premedication in preschool children undergoing dental surgery reduced emergence agitation without delaying hospital discharge.