Auditory Brainstem Response in Preterm Infants in the Neonatal Intensive Care Unit

Objective To analyze auditory brainstem response (ABR) findings of preterm and term infants in the neonatal intensive care unit (NICU) with perinatal problems. Study Design Case series with chart review. Setting Secondary care hospital. Methods Analysis consisted of a consecutive series of 101 infants (69 preterm and 32 term) admitted in the NICU of Hospital Fernando Fonseca between 2016 and 2018 with perinatal problems who underwent an ABR evaluation. Results The major perinatal problems identified were hyperbilirubinemia, intravenous gentamicin >5 days, mechanical ventilation >5 days, congenital cytomegalovirus infection, meningitis, and periventricular hemorrhage. Gentamicin use significantly increased the absolute latency of wave I in preterm infants (95% CI, 0.01-0.37;P= .037). Mechanical ventilation significantly decreased the latency of wave V and intervals I-V and III-V in preterm infants (95% CI, -0.35 to -0.22;P= .026; 95% CI, -0.33 to -0.00;P= .001; 95% CI, -0.46 to 0.12;P= .049). Congenital cytomegalovirus significantly decreased interval III-V in preterm infants (95% CI, -0.36 to -0.01;P= .042). Multivariate analysis revealed that gentamicin use, lower gestational age, and lower birth weight predicted an increased ABR threshold in preterm infants (95% CI, 1.64-15.31;P= .016; 95% CI -1.72 to -0.09;P= .030; 95% CI, -14.55 to -0.63;P= .033). ABR measurements in term infants were not significantly altered, with the exception of an increased latency of wave III with a lower gestational age (95% CI, -0.49 to -0.01;P= .038). Conclusions These findings suggest that perinatal problems in the NICU significantly impair the ABR threshold and the auditory pathway maturational process in preterm but not term infants.