title: Intraoperative electrically elicited stapedius reflex threshold is related to the dosage of hypnotic drugs in general anesthesia.
abstract: Today cochlear implantation is a widely used means of treatment in deafness and severe hearing disorders in adults, children, and infants. Postoperative fitting of the externally worn speech processor is very important for successful use of the cochlear implant. However, especially in infants and young children, this fitting process can be difficult because of limited communication capabilities. The use of intraoperatively obtained stapedius reflex thresholds has been proposed for postoperative speech processor fitting, but the influence of anesthetics on threshold values needs to be taken into account. In a retrospective study with 20 patients between 3 and 43 years of age, a highly significant correlation between the dosage of methohexital and the mean stapedius reflex threshold value could be shown (r = 0.65, p = .002). We conclude that more reliable threshold values can be obtained by reducing the dosage of hypnotics to achieve a lighter level of hypnosis during stapedius reflex measurement. To achieve a light, but still sufficient level of hypnosis, electroencephalographic monitoring including automatic interpretation of the complex raw signal should be used.
authors.affiliation: Department of Anesthesiology, Hannover Medical School, Hannover, Germany. ab.schultz@t-online.de
authors.forename: Arthur
authors.initials: A
authors.lastname: Schultz
authors.forename: Frank Andreas
authors.initials: FA
authors.lastname: Berger
authors.forename: Benno Paul
authors.initials: BP
authors.lastname: Weber
authors.forename: Ulrich
authors.initials: U
authors.lastname: Grouven
authors.forename: Oliver
authors.initials: O
authors.lastname: Niclaus
authors.forename: Ekkehard
authors.initials: E
authors.lastname: Lüllwitz
authors.forename: Barbara
authors.initials: B
authors.lastname: Schultz
mesh_terms: D000293:Adolescent; D000328:Adult; D000768:Anesthesia, General; D018686:Anesthetics, Intravenous / Q000008:administration & dosage*; D002648:Child; D002675:Child, Preschool; D019929:Cochlear Implantation; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D004569:Electroencephalography; D006801:Humans; D007432:Intraoperative Period; D008723:Methohexital / Q000008:administration & dosage*; D012022:Reflex, Acoustic / Q000187:drug effects*; D012189:Retrospective Studies; D012684:Sensory Thresholds; D013198:Stapedius / Q000187:drug effects* / Q000502:physiology
chemical_list: D018686:Anesthetics, Intravenous; D008723:Methohexital