title: Effect of headphones on sevoflurane requirement for MRI.
abstract: BACKGROUND
  Acoustic noise may have adverse effects, even in patients under general anesthetic.
  
  
  OBJECTIVE
  We aimed to determine the effect of headphones on sevoflurane requirements in children undergoing general anesthesia for an MRI scan.
  
  
  METHODS
  Children scheduled for MRI were enrolled in the study. Sevoflurane was used for general anesthesia in all children. Patients were randomly divided into two groups, one to wear headphones and the other none. After reaching a predetermined end-tidal concentration, the MRI scan was initiated, and the patient was evaluated by an observer blinded to the concentration of sevoflurane. Awakening was defined as eye opening, onset of continued purposeful movement or phonation. Using the Dixon up-and-down method, each target concentration was determined by the response of the previous child in the same group.
  
  
  RESULTS
  The study included 28 children undergoing MRI. There was a significant difference in ED50 between the two groups (0.92, 0.81-1.02, vs. 0.47, 0.42-0.63; P < 0.001). The times to spontaneous arm and leg movements, eye opening and discharge from the post-anesthesia care unit were significantly shorter in patients with headphones than in those without (P < 0.001). However, there was no difference in times to hospital discharge (P = 0.056).
  
  
  CONCLUSIONS
  Noise-concealing headphones decrease inhalational anesthetic requirements and facilitate recovery. We recommend the routine use of headphones in children undergoing an MRI scan.
authors.affiliation: Department of Anesthesiology, Adnan Menderes University, Aydin, Turkey.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Oğurlu
authors.forename: Mehmet Emin
authors.initials: ME
authors.lastname: Orhan
authors.forename: Salih
authors.initials: S
authors.lastname: Çinar
authors.forename: Ertan
authors.initials: E
authors.lastname: Piri
authors.forename: Ercan
authors.initials: E
authors.lastname: Kurt
authors.forename: Necdet
authors.initials: N
authors.lastname: Sut
authors.forename: Alparslan
authors.initials: A
authors.lastname: Turan
mesh_terms: D000762:Anesthesia Recovery Period; D000768:Anesthesia, General / Q000295:instrumentation*; D018681:Anesthetics, General / Q000008:administration & dosage; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D004430:Ear Protective Devices; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000295:instrumentation*; D007223:Infant; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage*; D009622:Noise / Q000517:prevention & control*; D000077149:Sevoflurane; D016896:Treatment Outcome
chemical_list: D018681:Anesthetics, General; D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane