[Relationship between brainstem auditory evoked potential and serum neuron-specific enolase in neonates with asphyxia].

OBJECTIVE: To study the correlation between brainstem auditory evoked potential (BAEP) and serum neuron-specific enolase (NSE) in neonates with asphyxia and explore the role of NSE in the evaluation of hearing impairment following asphyxia.

METHODS: Fifty-two term neonates with asphyxia, including 38 cases of simple asphyxia (mild: 23 cases; severe: 15 cases) and 14 cases of asphyxia complicated by hypoxic-ischemic encephalopathy (HIE), were enrolled. In the double-blind trial, BAEP and NSE were simultaneously detected 7 days after birth. The patients who did not pass BAEP test received another BAEP and NSE examinations 3 months after birth. Thirty healthy term neonates served as normal control group.

RESULTS: Of the 52 neonates with asphyxia, 50.0% and 21.2% of patients failed the initial and the second BAEP tests, respectively. The detection rates of BAEP anomalies in the simple severe asphyxia group in the initial and the second tests (63.3% and 26.3%, respectively) were significantly higher than those in the simple mild asphyxia group (36.9% and 5.9%, respectively)(P<0.05). The neonates with asphyxia complicated by HIE showed a higher detection rate of BAEP anomalies in the second test compared with the asphyxiated neonates without HIE (31.3% vs 16.7%; P<0.05). Mean serum NSE levels in asphyxiated neonates were significantly higher than those in normal controls (<0.01). There were significant differences in serum NSE levels between the neonates with mild and severe asphyxia (26.70+/-2.34 microg/L vs 17.18+/-3.16 microg/L; P<0.01). The asphyxiated neonates with HIE had serum NSE levels similar to the simple severely asphyxiated neonates. Serum NSE levels in patients who failed the initial BAEP test were significantly higher than those who passed the test (25.69+/-4.12 microg/L vs 17.15+/-3.09 microg/L; <0.01). Serum NSE levels had a positive correlation with wave V reaction threshold detected in the BAFP test (<0.05).

CONCLUSIONS: The serum level of NSE is closely correlated with BAEP, and it may be useful to the evaluation of the hearing impairment and the outcome in neonates with asphyxia.