A Study on the Effects of Midazolam on Delirium After Sevoflurane Anesthesia in Pediatric Strabismus Surgery

A Study on the Effects of Midazolam on Delirium After Sevoflurane Anesthesia in Pediatric Strabismus Surgery

Comparative Study on the Effects of Capacities of Midazolam on Delirium After Sevoflurane Anesthesia in Pediatric Strabismus Surgery : a Randomized Double- Blinded Trial

Sevoflurane with its rapid induction and emergence, hemodynamic stability, and nonirritating airway properties, has acquired widespread acceptance in children. However, sevoflurane has been reported to be associated with emergence agitation in children, with a reported incidence of up to 80%. The purpose of this study is to verify that the prophylactic use of midazolam, which is a GABA A receptor inhibitor, given five minutes before the end of strabismus surgery reduces the incidence of emergence agitation after sevoflurane anesthesia in children. Simultaneously, this study aims to find out the proper dose of midazolam with minimum disturbance to patient's emergence time.

Sevoflurane is associated with a high incidence of emergence agitation in children. The etiology of emergence agitation is unclear. Some studies proposed that emergence agitation was related to a variable rate of neurologic recovery rate in different brain areas and immaturity of neurons. Inhalation anesthetics have been known to exert transient paradoxical excitatory effects in both animals and human patients, especially in children. The gamma(γ)-aminobutyric acid (GABA)A receptor is the target depressant effect site of most anesthetic drugs including sevoflurane. Midazolam acts on the benzodiazepine binding site of GABAA receptors and results in inhibitory effects on the central nervous system. The effect of midazolam premedication, as well as midazolam administration at the end of surgery, on suppressing emergence agitation has been studied. However, the effect of midazolam on emergence agitation is still controversial. This study aims to figure out the effect of midazolam at the end of surgery on emergence agitation during the recovery period, and find out the proper dose of midazolam with minimum disturbance to patient's emergence time.

This group will be injected intravenous midazolam 0.03mg/kg five minutes before the end of surgery. If emergence agitation is severe, the patients will be treated by psychological support from the parents or nurse and intravenous fentanyl 1㎍/kg.

This group will be injected intravenous midazolam 0.05mg/kg five minutes before the end of surgery. If emergence agitation is severe, the patients will be treated by psychological support from the parents or nurse and intravenous fentanyl 1㎍/kg.

This group will be injected intravenous normal saline five minutes before the end of surgery. If emergence agitation is severe, the patients will be treated by psychological support from the parents or nurse and intravenous fentanyl 1㎍/kg.

The time of emergence is defined as time interval from the time of discontinuation of sevoflurane to the time of extubation.

Agitation is assessed immediately after extubation, and continuously thereafter until participants are calm. Emergence agitation is evaluated using the four-point emergence scale and the pediatric anesthesia emergence delirium scale. The highest scores are recorded.

Inclusion Criteria: American Society of Anesthesiologists physical status I and II patients Aged one to 13 years scheduled to undergo strabismus surgery under general anesthesia Willing to be assigned to any of the study intervention groups Exclusion Criteria: Refusal by parents Neurological disease Developmental delay History of any previous surgery Airway disease American Society of Anesthesiologists physical status score of III or IV