Comparison of ketamine vs dexmedetomidine given prior to extubation for prevention of emergence agitation in pediatric patients undergoing tonsillectomy- A double blinded randomized control trial.

•Emergence agitation (EA) is a phenomenon that includes restlessness, disorientation, excitation, non-purposeful movement, inconsolability, thrashing, and incoherence during early recovery from general anesthesia. The incidence of Emergence agitation varies widely from approximately 0.25% to 90.5%, according to age, assessment tool used, definitions, anaesthesia techniques, type of surgery, and time at which Emergence agitation is assessed during recovery.

•  The incidence of emergence agitation after sevoflurane anaesthesia estimated at 80%. Emergence agitation occurs most frequently in preschool children during the early stage of emergence from anaesthesia.

•  Emergence agitation is commonly self-limited and happens within first 30 min of stay in a postanesthesia care unit (PACU) and also can lead to disconnection of monitoring devices or intravenous catheter, physical damage, falling, increase risk of bleeding.

•Ketamine is a N-methyl-D-aspartate (NMDA) receptor antagonist with a strong analgesic effect if given in less than anesthesia-induction dose . At small doses (<1 mg/kg), it does not cause respiratory depression and has little effect on the heart rate and blood pressure .

  Dexmedetomidine is a highly selective α2 adrenergic receptor agonist which can produce pharmacological effects of anxiolysis, sedation, and analgesia without overt respiratory and circulatory inhibition in a routine dose. Dexmedetomidine can improve the cognitive function in children during recovery from general anesthesia and contributes to dose-dependent inhibition of emergence agitation after medical procedures .