Study of distortion-product otoacoustic emissions during hypothermia in humans

SummaryAimTo evaluate the function of cochlear outer hair-cells under the influence of extra-corporeal circulation and moderate hypothermia during cardiac surgery.Study DesignProspective clinical study.MethodsDistortion-product otoacoustic emissions (DPOAE) were registered before surgery, immediately after general anesthesia induction, during extra-corporeal circulation with moderate hypothermia and after the surgical procedure. Results: Comparison of response-amplitudes before and after surgery and before and after general anesthesia initiation did not demonstrate statistical difference. Comparison of amplitudes before and after extra-corporeal circulation with moderate hypothermia demonstrated a statistically significant decrease in responses amplitudes during hypothermia.ConclusionsThe amplitudes of DPOAE decreased during moderate hypothermia induced during extra-corporeal circulation.