Study of brainstem auditory evoked response in asphyxiated neonates

ABSTRACT

The present study was undertaken to evaluate the effect of neonatal asphyxia on brainstem auditory evoked response [B A E R] and the possible reversibility of abnormal BAER on follow up after 3 months of age. Prospective case control study was done in the neonatal special care unit and neurology department, at EL-Minia university hospital. Twenty five term neonates with 5-minute Apgar score< 6, who had hypoxic ischemic encephalopathy [HIE] or asphyxia underwent BAER testing with follow up at 3 months. Twenty age and sex-matched normal neonates served as control. Denever development screening test [Denever II] was performed at 3 months of age. Twelve out of twenty five [48 percent] neonates with birth asphyxia showed abnormalities on initial BAER. The commonest abnormalities seen were raised threshold of interside latency difference in 8/12 neonates [66.7 percent], followed by prolongation of latencies of various waves in 6/12 neonates [50 percent]. Other abnormalities observed were prolonged intervene interval [16.7 percent] and prolonged interside interval difference [8.3 percent]. There were a significant association of BAER abnormalities with duration of neurological findings more than 5 days and stages of HIE. On follow up of 12 cases at 3 months of age, abnormalities in BAER reverted back to normal in 11 cases [91.6 percent]. The Denever Developmental screening test [Denever II] was suspect in 3 cases only. It was concluded that BAER abnormalities in neonatal asphyxia are transient and revert back to normal in most cases on follow up at 3 months of age and BAER is simple non invasive tool but does not appear to be a useful one for early detection of neurological handicaps