Cochlear Dysfunction Associated with Decompression from 300-ft Hyperbaric Chamber Dives

Abstract

J. D. Harris has reported [U. S. Naval Submarine Medical Center, Conn., Rep. No. 591 (5 Aug. 1969)] severe neurosensory hearing loss in Navy divers due to decompression sickness. In an attempt to develop an animal model for this condition with verification of cochlear involvement, we compressed guinea pigs at 1 atm/min to 300 ft in air. Time at 300 ft was held constant at 6 min while decompression schedules were shortened from Navy diving tables. Animals were dived with an open bulla to eliminate barotrauma to the ear drum, and cochlear potentials were measured postdive. The general finding was the onset of auditory loss 10–15 min postdive. Severe loss (40–50 dB} was usually present by at least 1 h postdive. The loss remained stable 2–5 h postdive, and became more severe 6 h postdive.