title: Influence of anaesthetic agents on transient evoked otoacoustic emissions and stapedius reflex thresholds.
abstract: This aim of this study was to determine the effect of anaesthetic agents on stapedius reflex (SR) thresholds and transient evoked otoacoustic emissions (TEOAE). Fifty patients who were scheduled for operation and who had normal hearing were included in the study. All were given midazolam for premedication and propofol for induction. Anaesthesia was maintained in five different ways in each group of 10 patients. Groups I-IV received inhalational anaesthesia: group I received 70 per cent N2O plus 30 per cent O2, group II sevoflurane, group III desflurane and group IV halothane. Group V received total intravenous anaesthesia with propofol plus sufentanil. The SR and TEOAE of the patients were measured four times: on the day before surgery (first measurement), after premedication (second measurement), after induction of anaesthesia (third measurement) and during maintenance of anaesthesia (fourth measurement). Midazolam significantly increased ipsilateral and contralateral SR thresholds and decreased TEOAE wave reproducibility. Propofol significantly increased only the SR thresholds. The other anaesthetic agents significantly increased only the contralateral reflex thresholds. Of these, the highest increase was seen after sevoflurane and the lowest after halothane. The changes in TEOAE wave reproducibility due to anaesthetic agents used for maintenance were not significant. We concluded that midazolam premedication may affect audiological evaluation with SR and TEOAE tests, and sevoflurane should not be used when it is necessary to measure SR under general anaesthesia.
authors.affiliation: Department of Otolaryngology, Faculty of Medicine, Trakya University, Edirne, Turkey.
authors.forename: Selis
authors.initials: S
authors.lastname: Guven
authors.forename: Abdullah
authors.initials: A
authors.lastname: Tas
authors.forename: Mustafa K
authors.initials: MK
authors.lastname: Adali
authors.forename: Recep
authors.initials: R
authors.lastname: Yagiz
authors.forename: Aysin
authors.initials: A
authors.lastname: Alagol
authors.forename: Cem
authors.initials: C
authors.lastname: Uzun
authors.forename: Muhsin
authors.initials: M
authors.lastname: Koten
authors.forename: Ahmet R
authors.initials: AR
authors.lastname: Karasalihoglu
mesh_terms: D000293:Adolescent; D000328:Adult; D000777:Anesthetics / Q000009:adverse effects / Q000494:pharmacology*; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D001309:Auditory Threshold / Q000187:drug effects; D002648:Child; D000077335:Desflurane; D005260:Female; D006221:Halothane / Q000494:pharmacology; D006801:Humans; D007530:Isoflurane / Q000031:analogs & derivatives / Q000494:pharmacology; D008297:Male; D008738:Methyl Ethers / Q000494:pharmacology; D008874:Midazolam / Q000494:pharmacology; D008875:Middle Aged; D017084:Otoacoustic Emissions, Spontaneous / Q000187:drug effects*; D015742:Propofol / Q000494:pharmacology; D011446:Prospective Studies; D012022:Reflex, Acoustic / Q000187:drug effects*; D015203:Reproducibility of Results; D000077149:Sevoflurane; D013198:Stapedius / Q000187:drug effects* / Q000502:physiology
chemical_list: D000777:Anesthetics; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D000077149:Sevoflurane; D000077335:Desflurane; D007530:Isoflurane; D008874:Midazolam; D006221:Halothane; D015742:Propofol