Premium
Cochlear hypoxia and the compound action potentials
Author(s) -
Hildesheimer Minka,
Muchnik Hava,
Rubinstein Moshe
Publication year - 1988
Publication title -
the laryngoscope
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.181
H-Index - 148
eISSN - 1531-4995
pISSN - 0023-852X
DOI - 10.1288/00005537-198805000-00016
Subject(s) - hypoxia (environmental) , acidosis , chemistry , compound muscle action potential , guinea pig , anesthesia , oxygen , medicine , electrophysiology , organic chemistry
A relatively restricted area, including the ear, was perfused in guinea pigs with hypoxic blood having a pO 2 of 10, 20, and 30 mm Hg, respectively. The changes induced to the cochlear action potentials were analyzed and the results compared with those obtained in a previous study in which the guinea pigs were rendered hypoxemic by ventilating them with air entrapped in a closed circuit from which the CO 2 was continously absorbed. The changes induced to the cochlear action potentials by both methods were very similar. However, while using the territorial model for inducing hypoxia, 75% of the animals showed a threshold shift at a blood pO 2 of 20 mm Hg and with the general model all the animals showed a threshold shift at 25 mm Hg blood pO 2 . In other words, if the hypoxic condition affected the whole body, other factors such as a slight, but continuous tendency to acidosis with significant increase in blood lactic acid concentration could join the oxygen deficit in affecting cochlear function.