Brainstem auditory evoked response in neonates with birth asphyxia.

OBJECTIVE To determine the brainstem auditory evoked response (BAER) abnormalities and their reversibility in neonates with birth asphyxia. DESIGN Prospective case control study. SETTING Tertiary care teaching hospital. METHODS 30 term Neonates with 5-min Apgar < 6 and hypoxic ischemic encephalopathy (HIE) underwent BAER testing with follow up at 3 months. An equal number of normal term neonates served as controls. RESULTS 13 out of 30 (43.3%) neonates with birth asphyxia showed some abnormality in BAER wave form. The commonest type of BAER abnormalities seen were transient prolongation of latencies of various waves (69.2%) and prolonged interside latency difference (69.2%). Other abnormalities observed were prolonged interwave interval (23.1%) and prolonged interside interval difference (7.7%). Abnormalities in BAER were significantly associated with stages of HIE and duration of neurological abnormalities more than 5 days. On follow up of 16 cases at 3 months of age, BAER abnormalities reverted back to normal in all the neonates. The Denver Developmental Screening Test (DENVER II) was suspect in 4 cases but the BAER was normal. CONCLUSION BAER abnormalities in asphyxic neonates are transient and revert back to normal at 3 months of age. BAER does not appear to be a useful tool for early detection of neurological handicaps.