Anesthetic Depth and the Incidence of Emergence Agitation in Children Undergoing Strabismus Surgery

This study evaluates the association between the depth of general anesthesia and the occurrence of emergence agitation (EA). The investigators hypothesized that optimal level of anesthetic depth could decrease the incidence of EA in children undergoing strabismus surgery compared to the deep level of anesthetic depth.

EA is characterized by dissociated state of consciousness, in which the children are inconsolable, irritable, uncooperative, thrashing, crying, moaning or incoherent. Several predisposing factors for EA include post-operative pain, rapid emergence from general anesthesia, use of volatile anesthetics, type and site of operation (usually head \& neck surgeries), agitation on induction, airway obstruction, hyperthermia or hypothermia. The effect of anesthetic depth on the EA has rarely been evaluated in pediatric population, even though postoperative delirium or postoperative cognitive dysfunction (POCD)corresponds to the EA identically. In this study, the concentration of anesthetics was not managed on purpose to lower the BIS score. Patients were allocated to each group based on the result of average BIS score during the operation.