Auditory brainstem responses in preterm neonates: maturation and follow-up

Area of Science:

• Neonatal Medicine
• Audiology
• Neuroscience

Background:

• Neonatal intensive care units (NICUs) care for premature infants at high risk for hearing impairment.
• Auditory brainstem response (ABR) screening is commonly used to detect hearing deficits in this population.

Purpose of the Study:

• To evaluate the effectiveness of ABR screening in NICU patients.
• To determine the correlation between ABR test results and postconceptual age (PCA).

Main Methods:

• Seventy-five NICU patients underwent ABR screening at 40 dB and 70 dB.
• Presence of wave V was the criterion for passing the ABR test.
• Follow-up hearing tests or historical data were collected for infants who failed the screening.

Main Results:

• ABR test results were strongly correlated with PCA; passing at 70 dB occurred at 32 weeks PCA, and at 40 dB occurred at 40 weeks PCA.
• 44 infants failed the ABR screen before NICU discharge.
• Most failures were attributed to prematurity, with only one confirmed case of severe hearing loss among survivors.

Conclusions:

• The high failure rate of ABR screening in NICU infants appears primarily due to physiological immaturity.
• The effectiveness of routine ABR screening in the NICU setting is questionable.
• Further research is needed to refine hearing assessment protocols for premature infants.