title: A dose-finding study of preoperative intravenous dexmedetomidine in children's emergence delirium after epiblepharon surgery.
abstract: OBJECTIVE
  Emergence delirium (ED) is a leading problem in children after general anesthesia. Dexmedetomidine (DEX) can be administered prior to general anesthesia to decrease ED, although wide ranges of dose are used. This study was conducted to investigate the proper dosages of DEX to attenuate children's ED after sevoflurane anesthesia.
  
  
  METHODS
  Twenty-five children, aged 3 to 9, undergoing repair of epiblepharon were studied. A chosen dosage of DEX was infused for 10 minutes in the preoperative holding area. The dose of DEX started from 0.25 µg/kg, and then was increased or decreased by 0.25 µg/kg depending on the response of the previous patient, using the Dixon up-and-down method. After the surgery under general anesthesia with sevoflurane, ED was assessed by the Cravero 5-point emergence agitation scale (5-point scale) at the postanesthesia care unit. The 50% and 95% effective concentrations (EC50 and EC95 ) of DEX to attenuate ED were calculated by isotonic regression estimators.
  
  
  RESULTS
  The EC50 to attenuate ED was 1.0 (95% confidence interval [CI] 0.29 to 1.71) and EC95 was 1.43 µg/kg (95% CI -1.73 to 4.60). No patient failed parental separation while the Modified Observer's Assessment of Alertness/Sedation Scale at the end of the infusion was scattered from 1 to 5. One child who received 1.50 µg/kg had brief desaturation but recovered soon after being given a verbal command.
  
  
  CONCLUSIONS
  Dexmedetomidine can be safely used between 1.0 and 1.43 µg/kg to attenuate children's ED after sevoflurane anesthesia.
authors: Department of Anesthesiology and Pain Medicine, School of Medicine, Yeungnam University, Daegu - Republic of Korea.
authors: Sohee
authors: S
authors: Yang
authors: Haemi
authors: H
authors: Lee
mesh_terms: D058647:Adrenergic alpha-2 Receptor Agonists / Q000008:administration & dosage*; D018712:Analgesics, Non-Narcotic / Q000008:administration & dosage; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003693:Delirium / Q000209:etiology / Q000517:prevention & control*; D020927:Dexmedetomidine / Q000008:administration & dosage*; D005141:Eyelid Diseases / Q000601:surgery*; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage; D013508:Ophthalmologic Surgical Procedures; D011183:Postoperative Complications / Q000517:prevention & control; D011300:Preoperative Care; D011595:Psychomotor Agitation; D000077149:Sevoflurane
chemical_list: D058647:Adrenergic alpha-2 Receptor Agonists; D018712:Analgesics, Non-Narcotic; D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D020927:Dexmedetomidine