Emergence agitation and delirium are well-described phenomena during emergence from general anaesthesia, especially in the paediatric population.

Emergence Agitation (EA) is an “unpleasant state of extreme arousal” characterized by non-purposeful movement, restlessness, thrashing, incoherence, inconsolability, and unresponsiveness usually following emergence from General Anaesthesia. The true incidence of EA in children is unclear but has been estimated to be between 10 - 80 %.

Emergence Delirium (ED)  is an altered state of consciousness, which begins with emergence from anesthesia and continues throughout the early recovery period. ED is a disturbance of awareness of, or attention to, the child’s environment, and manifests as disorientation, hyperactive/hypoactive behavior, and hypersensitivity in the immediate period after anesthesia.

Although there is significant ongoing research on the incidence, risk factors, and the probable consequences of EA/ED, neurosurgical procedures have generally been exempt owing to the complexity in differentiation between the neurological conditions and the effect of recovery from anaesthetics.  A study done in the adult neurosurgical population has shown a higher incidence of EA in neurosurgical patients (29%).

Children undergoing craniotomy are more vulnerable to the stress that follows EA/ED. In a recent observational study done in our institution, the incidence of emergence agitation was 28% in the paediatric population undergoing craniotomy.

Total intravenous anaesthetic (TIVA) techniques with propofol, which has been the mainstay of neurosurgical practice have been associated with a reduced incidence of EA/ED in other surgical procedures. However, in children, it is often necessary to use high concentration volatile anaesthetics to induce general anaesthesia before initiation of TIVA as they may not cooperate for intravenous access which predisposes them to develop EA/ED.

Dexmedetomidine is a selective alpha-2 receptor agonist acting on alpha-2 receptors in the locus ceruleous of the pons. Recently, Dexmedetomidine is beneficial in reducing the incidence of EA/ED in children undergoing general anaesthesia. However, there is no literature regarding its use in the paediatric neurosurgical population.

We hypothesize that the use of intravenous dexmedetomidine as an infusion at a dose of 0.5mcg/kg/hr could reduce the incidence of EA/ED in paediatric patients undergoing craniotomy.