EFFECT OF HYPOTHERMIC TECHNIQUES ON COCHLEAR FUNCTION
 
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1
Department of Pediatrics, Ain Shams University, Cairo, Egypt
 
2
Department of Audiology, Ain Shams University, Cairo, Egypt
 
 
Publication date: 2011-09-30
 
 
Corresponding author
Lobna H. Khalil   

Dr. Lobna Hamed Khalil, Ain Shams University Specialized Hospital, Audiology Unit, El-Khalifa El-Maammoun St. Post Code 11588, Cairo, Egypt, Phone: +202 22709207, +2 0195041332, Fax: +202 22709207, e-mail: hamedlobna@yahoo.com
 
 
J Hear Sci 2011;1(3):45-48
 
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ABSTRACT
Background:
Mild to moderate hypothermia are the basis of neuroprotective strategies during cardiopulmonary bypass operations. Mild hypothermia has a protective role on the cochlea and could prevent its damage during long lasting operations. However, deep hypothermia may result in cochlear cells injury. This research aims to assess the effect of different hypothermic techniques on cochlear functions in children after open heart surgery.

Material and Methods:
Forty children with various acyanotic heart diseases who underwent open heart surgery were included in this study. They were subdivided into two groups; Group I: twenty patients who were subjected to mild hypothermic technique (33° to 37°C), Group II: twenty patients who were subjected to moderate hypothermic technique (28° to 32°C). Audiological assessment included basic evaluation and otoacoustic emissions testing.

Results:
All patients had normal hearing. Both study groups had Distortion product otoacoustic emissions (DPOAEs) amplitude >3 dB SPL at all frequencies. However, group II showed lower amplitude at all frequencies with statistically significant difference at high frequencies (4.416–8.837 KHz) compared to group I (P<0.01). 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 the overall TEOAEs amplitude as well as at high frequencies (2–4 KHz) (P<0.01).

Conclusions:
Patients exposed to moderate hypothermic technique had subtle cochlear dysfunction. Care should be taken for choice of moderate hypothermic technique in open heart surgeries for children at risk for sensorineural hearing loss.

 
REFERENCES (14)
1.
Borin A, Cruz OLM: Study of distortion-product otoacoustic emissions during hypothermia in humans. Rev Bras Otorrinolaringol, 2008; 74(3): 401–9.
 
2.
Harry A, Wellons JR, Zacour RK: Adult Cardiac Surgery (Part A-General Considerations) – Cardiopulmonary Bypass. In: Mastery of Cardiothoracic Surgery, Kaiser LR, Kron IL, Spray TL (eds.), Lippincott Williams & Wilkins Companies, 2007; 305–14.
 
3.
Namyslowski G, Morawski K, Urban I et al: Influence of hypothermia and extracorporeal circulation on transiently evoked otoacoustic emission (TEOAE) in children operated on for various heart defects. Otolaryngol Pol, 2003; 57(2): 263–69.
 
4.
Veuillet E, Gartner M, Champsaur G et al: Effects of hypothermia on cochlear micromechanical properties in humans. J Neurol Sci, 1997; 145(1): 69–76.
 
5.
Maxon A, White K, Vohr B, Behrans T: Using Transient Evoked Otoacoustic Emission for Neonatal Hearing Screening. Br J. Audiol, 1993; 27: 149–53.
 
6.
Varan B, Tokel K, Yilmaz G: Malnutrition and growth failure in cyanotic and acyanotic congenital heart disease with and without pulmonary hypertension. Arch Dis Child, 1999; 81: 49–52.
 
7.
Arenberg IK, Allen GW, DeBoer A: Sudden deafness imme diately following cardiopulmonary bypass. J Laryngol Otol, 1972; 86: 73–77.
 
8.
Plasse HM, Spencer FC, Mittleman M, Frost JO: Unilateral sudden loss of hearing. An unusual complication of cardiac operation. J Thorac Cardiovasc Surg, 1980; 79: 822–26.
 
9.
Brownson RJ, Stroud MH, Carver WF: Extracorporeal cardiopulmonary bypass and hearing. Arch Otolaryngol Head Neck Surg, 1971; 93: 179–82.
 
10.
Seifert E, Brand K, van de Flierdt K et al: The influence of hypothermia on outer hair cells of the cochlea and its efferents. Br J Audiol, 2001; 35: 87–98.
 
11.
Erdinc A, Güzin A, Babür et al: Effect of hypothermia on Distortion Product Otoacoustic Emission Findings in Children Undergoing Congenital Open Heart Surgery. Int Adv Otol, 2009; 5: (1).
 
12.
Watanabe F, Koga K, Hakuba N, Gyo K: Hypothermia prevents hearing loss and progressive hair cell loss after transient cochlear ischemia in gerbils. Neuroscience, 2001; 102(3): 639–45.
 
13.
Hyodo J, Hakuba N, Koga K et al: Hypothermia reduces glutamate efflux in perilymph following transient cochlear ischemia. Neuroreport, 2001; 12: 1983–87.
 
14.
Takeda S, Hakuba N, Yoshida T et al: Postischemic mild hypothermia alleviates hearing loss because of transient ischemia. Neuroreport, 2008; 19(13): 1325–28.
 
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