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Published on: February 29, 2020
Cochlear Dysfunction in Children following Cardiac Bypass Surgery
Mona M El Ganzoury1, Terez B Kamel, Lobna H Khalil
1Department of Pediatrics, Ain Shams University, Cairo, Egypt.
Insights
Moderate hypothermia during pediatric open-heart surgery may cause subtle cochlear dysfunction. Otoacoustic emissions testing can detect early hearing changes in these children.
Area of Science:
- Otorhinolaryngology
- Pediatric Cardiology
- Anesthesiology
Background:
- Sensorineural hearing loss is a risk following procedures involving extracorporeal circulation and hypothermia.
- While mild hypothermia may protect the cochlea, deep hypothermia can cause injury.
- Auditory function assessment is crucial in children undergoing cardiac surgery.
Purpose of the Study:
- To evaluate auditory function in children post-open-heart surgery.
- To compare the effects of mild versus moderate hypothermia on cochlear health.
- To identify potential risks of different hypothermic techniques on hearing.
Main Methods:
- Forty children with acyanotic heart disease were divided into two groups: mild hypothermia (33-37°C) and moderate hypothermia (28-32°C).
- Audiological assessments included basic evaluations and otoacoustic emissions testing (distortion-product and transient evoked).
- Comparative analysis of auditory function between the two hypothermia groups was performed.
Main Results:
- Both groups showed distortion-product otoacoustic emissions (DPOAEs) amplitude >3 dB SPL.
- The moderate hypothermia group exhibited lower DPOAE amplitudes, particularly at high frequencies.
- Transient evoked otoacoustic emissions (TEOAEs) showed significantly more partial passes and reduced amplitude in the moderate hypothermia group.
Conclusions:
- Moderate hypothermic techniques in pediatric cardiac surgery are associated with subtle cochlear dysfunction.
- Otoacoustic emissions are effective for early detection of subclinical cochlear impairment in these patients.
- This highlights the importance of audiological monitoring after cardiac procedures involving moderate hypothermia.
Abstract:
Background. Sensorineural hearing loss after procedures including extracorporeal circulation and hypothermia is greater than general population. Mild hypothermia has a protective role on cochlea; however, deep hypothermia may result in cochlear injury. This research aimed at assessing auditory function in children after open heart surgery in relation to different hypothermic techniques. Subjects and Methods. Forty children with acyanotic heart diseases who underwent open heart surgery were included: group I: twenty patients subjected to mild hypothermia (33° to 37°C), group II: twenty patients subjected to moderate hypothermia (28° to 32°C). Audiological assessment included basic evaluation and otoacoustic emissions. Results. Both groups had distortion-product otoacoustic emissions (DPOAEs) amplitude >3 dB SPL at all frequencies. However, group II showed lower amplitude at overall and at high frequencies (4.416-8.837 KHz) than group I. Transient evoked otoacoustic emissions (TEOAEs) showed partial pass in three patients of group I (15%) and in 15 patients of group II (75%). Moreover, group II showed statistical significant reduction in overall TEOAEs amplitude as well as at high frequencies (2-4 KHz). Conclusions. Patients exposed to moderate hypothermic technique had subtle cochlear dysfunction. Otoacoustic emissions should be used for early detection of subtle cochlear dysfunction in operated cardiac children.