title: Functional impairment of the auditory pathway after perinatal asphyxia and the short-term effect of perinatal propofol anesthesia in lambs.
abstract: BACKGROUND
  Sensorineural hearing loss (SNHL) is a common feature in the postasphyxial syndrome in newborns. Several anesthetic drugs have been proposed to attenuate secondary neuronal injury elicited by hypoxia-ischemia. We hypothesized that propofol anesthesia reduces auditory impairment after perinatal asphyxia in comparison with isoflurane.
  
  
  METHODS
  Twenty-three pregnant ewes were randomized to propofol or isoflurane anesthesia and sedation. The lambs underwent in utero umbilical cord occlusion (isoflurane n = 5; propofol n = 7) and were compared with sham-treated animals (isoflurane n = 5; propofol n = 6) at a gestational age of 133 d. For 8 h after delivery by cesarean section, repeated auditory brainstem responses (ABRs) were recorded to obtain hearing thresholds, peak amplitudes, latencies, and interpeak latencies.
  
  
  RESULTS
  Significantly elevated mean thresholds, diminished amplitudes, and elevated latencies were observed in the asphyxia group relative to the control group through the observation period. Comparison of anesthetic treatment in the asphyxia group revealed a significantly lower elevation in threshold and less impairment in the ABR amplitudes and latencies during propofol anesthesia as compared with isoflurane anesthesia.
  
  
  CONCLUSIONS
  Our results support the hypothesis that anesthesia with propofol has a preventive effect on the functional changes to the auditory pathway in the event of perinatal asphyxia.
authors.affiliation: Department of Otorhinolaryngology/Head and Neck Surgery, Maastricht University Medical Centre, Maastricht, The Netherlands. diane.smit@mumc.nl
authors.forename: Adriana L
authors.initials: AL
authors.lastname: Smit
authors.forename: Matthias
authors.initials: M
authors.lastname: Seehase
authors.forename: Robert J
authors.initials: RJ
authors.lastname: Stokroos
authors.forename: Reint K
authors.initials: RK
authors.lastname: Jellema
authors.forename: Lilian
authors.initials: L
authors.lastname: Felipe
authors.forename: Michelene N
authors.initials: MN
authors.lastname: Chenault
authors.forename: Lucien J C
authors.initials: LJ
authors.lastname: Anteunis
authors.forename: Bernd
authors.initials: B
authors.lastname: Kremer
authors.forename: Boris W
authors.initials: BW
authors.lastname: Kramer
mesh_terms: D018686:Anesthetics, Intravenous / Q000008:administration & dosage* / Q000494:pharmacology; D000818:Animals; D001237:Asphyxia / Q000503:physiopathology*; D001306:Auditory Pathways / Q000187:drug effects*; D005260:Female; D011247:Pregnancy; D015742:Propofol / Q000008:administration & dosage* / Q000494:pharmacology; D012756:Sheep
chemical_list: D018686:Anesthetics, Intravenous; D015742:Propofol