Protective effect of isoflurane anesthesia on noise-induced hearing loss in mice.
OBJECTIVE
To examine the protective effect of general anesthesia with isoflurane against noise-induced hearing loss in mice.


METHODS
Animal study using noise stimulation and measurement of hearing in BALB/c mice.


METHODS
Mice were exposed to 122 dB peak equivalent sound pressure level click noise for 3 hours per day for 3 consecutive days with or without anesthesia using isoflurane. Hearing levels were measured and hair cell survival ratio was observed.


RESULTS
In mice without anesthesia, hearing threshold increased after noise stimulation (73.7 dB hearing level [HL]) and persisted for at least 1 month. However, in mice exposed to noise under anesthesia, hearing loss was less severe (44.1 dB HL) and had recovered more (26.5 dB HL) by one month. Histological examination showed hair cell survival was higher in anesthetized compared to non-anesthetized mice.


CONCLUSIONS
These data indicate isoflurane general anesthesia protects against noise-induced hearing loss and tissue damage in mice.
Kim
Joung Uk
JU
Department of Anesthesiology and Pain Medicine, Asan Medical Center, College of Medicine, University of Ulsan, Seoul, Korea.
Lee
Hyun Jung
HJ
Kang
Hun Hee
HH
Shin
Jin Woo
JW
Ku
Seung Woo
SW
Ahn
Joong Ho
JH
Kim
Young Jin
YJ
Chung
Jong Woo
JW
D000769:Anesthesia, Inhalation; D018685:Anesthetics, Inhalation / Q000627:therapeutic use*; D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D004195:Disease Models, Animal; D005072:Evoked Potentials, Auditory / Q000187:drug effects / Q000502:physiology; D005500:Follow-Up Studies; D006198:Hair Cells, Auditory / Q000473:pathology; D006317:Hearing Loss, Noise-Induced / Q000473:pathology / Q000503:physiopathology / Q000517:prevention & control*; D007530:Isoflurane / Q000627:therapeutic use*; D051379:Mice; D008807:Mice, Inbred BALB C; D012720:Severity of Illness Index
D018685:Anesthetics, Inhalation; D007530:Isoflurane