Estudo eletrofisiológico da audição em lactentes prematuros e a termo

Abstract

Introduction: Hearing is a complex and primordial meaning for the development of oral language. The Auditory Brainstem Response (ABR) is an efficient tool to monitor the maturation process of the auditory pathway by analyzing the latencies of waves I, III and V, and the electrophysiological threshold, therefore it is important to carry out further studies on these parameters in the child population. Objective: To establish reference values for the absolute latencies and interpeak intervals of waves I, III and V of the ABR and to analyze the relationship between the results of electrophysiological thresholds and latencies to the gestational age of neonates in a Neonatal Hearing Screening program. Methodology: This is a cross-sectional observational study. The sample consisted of 63 preterm and full-term newborns, divided into two groups according to gestational age on the day of the exam, group 1 (G1- 41 babies) - 27 to 37 weeks and group 2 (G2- 22 babies) -38 to 41 weeks assessed by means of Clinical ABR at an intensity of 80dBnHL to analyze the absolute latencies and interpeak intervals of waves I, III and V and also to investigate the electrophysiological threshold. The equipment used was Elios®, from the ECHODIA brand. For data analysis, t student´s and anova tests were used for comparison between groups when variables with symmetrical distribution and Mann Whitney and Spearman for variables with asymmetric distribution. Results: The mean age of group 1 (G1) was 33.59 weeks and group 2 (G2) was 39 weeks. G1 and G2 presented values of absolute latencies and interpeak intervals with averages without statistical difference. Regarding the electrophysiological threshold, G1 showed an average of 29.57dB and G2 showed an average of 26.93dB with p-value: 0.010. Proving the influence of gestational age on the electrophysiological threshold. In the relationship between electrophysiological threshold and IRDA, it was possible to observe that having one or more Risk Indicators for Hearing Impairment influences the electrophysiological threshold, whether preterm or not, babies with IRDA presented an electrophysiological threshold on average 29.31 and babies without IRDA in mean 24.72 with p-value: 0.041. Conclusion: The present study established reference values for absolute latencies and interpeak intervals for two groups of preterm and full-term gestational age. Through the analysis of electrophysiological thresholds, according to the gestational age, suggested the observation of these data to accompany the maturation of the auditory pathway. Contributing to best practices in electrophysiological assessment of neonates.