Factors associated with permanent hearing impairment in infants undergoing therapeutic hypothermia

Elisa Smit, Xun Liu, Hannah Gill, Hemmen Sabir, Sally L Jary, Marianne Thoresen

Research output: Contribution to journalArticle (Academic Journal)peer-review

13 Citations (Scopus)



To define the incidence of hearing impairment, document plasma gentamicin concentrations, and identify factors associated with permanent hearing impairment in infants subjected to therapeutic hypothermia for moderate or severe neonatal encephalopathy.

Study design

Data were collected prospectively in a regional center providing therapeutic hypothermia. Cooled infants at ≥36 weeks gestation with moderate or severe neonatal encephalopathy were analyzed if a full dataset was available (n = 108), including clinical variables and gentamicin trough levels. Infants with hearing impairment were identified, and survivors were followed up with neurodevelopmental evaluation at age 18 months. Stepwise logistic regression identified factors associated with hearing impairment.


Nine infants died, and among the survivors, 10.1% developed a permanent hearing impairment. The trough gentamicin level was above the recommended cutoff of 2 mg/L in 37% of the infants in the entire cohort and in 90% of the infants with hearing impairment. Logistic regression analysis identified high trough gentamicin level, low cord pH, and hypoglycemia (<46.8 mg/dL) in the first postnatal hour as significantly associated with hearing impairment. The need for inotropic support was close to significant (P = .055).


Hearing impairment was a common finding among cooled infants. Plasma gentamicin levels were commonly >2 mg/L. Based on these findings, we propose changes in gentamicin dosing interval and trough level monitoring to minimize the risk of potentially toxic levels in cooled newborns.

Original languageEnglish
Pages (from-to)995–1000
Number of pages6
JournalJournal of Pediatrics
Issue number4
Early online date25 Jul 2013
Publication statusPublished - Oct 2013


  • AABR, Automated auditory brainstem response; AOAE, Automated otoacoustic emissions; BSID-II, Bayley Scales of Infant Development, Second Edition; MDI, Mental Developmental Index; PDI, Pyschomotor Developmental Index


Dive into the research topics of 'Factors associated with permanent hearing impairment in infants undergoing therapeutic hypothermia'. Together they form a unique fingerprint.

Cite this