Prospective randomized trial to determine whether inhalational anesthetics have any effects on hearing function.
OBJECTIVE
The purpose of this study was to investigate and compare the effects of inhalation anesthetics (sevoflurane and isoflurane) on hearing function by using an audiometric test battery.


METHODS
A prospective, randomized, double-blind, clinical trial.


METHODS
University hospital.


METHODS
Fifty-three adult patients (American Society of Anesthesiologists I-II) scheduled for sinonasal surgery with intratracheal general anesthesia were enrolled in the study. The patients were premedicated with diazepam intramuscularly. Propofol 2 mg/kg (Diprivan, AstraZeneca, Wilmington, DE) was given intravenously (i.v.) for induction of general anesthesia. After endotracheal intubation with vecuronium i.v. (1 mg/kg), in group 1 (n = 27) sevoflurane 2% and in group 2 (n = 26) isoflurane 1.2% were used to maintain general anesthesia. All patients received nitrous oxide during maintenance.


METHODS
The patients' hearing function was measured before anesthesia and 24 hours after surgery by means of pure-tone audiometry, high-frequency pure-tone audiometry, and transient evoked otoacoustic emissions (TEOAEs) by the same clinician.


RESULTS
There were no statistically significant differences between the demographic data and the hemodynamic and respiratory parameters of the groups. No significant differences were found between groups in hearing thresholds of conventional pure-tone audiometry and extended high frequency (p > .05). For TEOAE responses, no statistically significant differences were determined between pre- and postoperative measurements (p > .05).


CONCLUSIONS
It was audiometrically demonstrated that general anesthesia did not affect the hearing function in any of the patients undergoing sinonasal surgery. These findings encourage the use of sevoflurane or isoflurane as a safe agent without any ototoxic effects in otorhinolaryngologic surgery with general anesthesia.
Buyukkocak
Unase
U
Department of Anesthesiology and Reanimation, Faculty of Medicine, Kirikkale University, Kirikkale, Turkey.
Kilic
Rahmi
R
Arikan
Osman Kursat
OK
Sert
Ozgur
O
Datli
Filiz
F
D000293:Adolescent; D000328:Adult; D000770:Anesthesia, Endotracheal; D018685:Anesthetics, Inhalation / Q000008:administration & dosage / Q000009:adverse effects*; D001299:Audiometry; D004311:Double-Blind Method; D005260:Female; D006309:Hearing / Q000187:drug effects*; D006801:Humans; D007530:Isoflurane / Q000008:administration & dosage / Q000009:adverse effects*; D008297:Male; D008738:Methyl Ethers / Q000008:administration & dosage / Q000009:adverse effects*; D008875:Middle Aged; D013517:Otorhinolaryngologic Surgical Procedures; D011446:Prospective Studies; D000077149:Sevoflurane; D055815:Young Adult
D018685:Anesthetics, Inhalation; D008738:Methyl Ethers; D000077149:Sevoflurane; D007530:Isoflurane