有缺氧病史早产儿在不同刺激速率下脑干听觉诱发电位的变化及意义

目的通过分析不同刺激速率下的脑干听觉诱发电位变化，观察有缺氧病史的早产儿在纠正胎龄足月时的脑功能状态。方法2002年7月至2004年7月复旦大学儿科医院新生儿科收治的早产儿，缺氧组：39例，有缺氧病史，除外其它听力及脑损伤高危因素；对照组：30例，无缺氧病史，无其他听力损伤高危因素。两组于纠正胎龄37~42周时进行脑干听觉诱发电位检查，声刺激速率为21.1/s、51.1/s和91.1/s，分析Ⅰ、Ⅲ、Ⅴ波的潜伏期、振幅、峰间期等参数，进行t检验。结果在60dBnHL刺激强度下，随刺激速率增加，各组Ⅰ、Ⅲ、Ⅴ波的潜伏期、峰间期均逐渐延长，振幅下降。在常规21.1/s时，缺氧组仅表现为Ⅴ波潜伏期和Ⅲ~Ⅴ峰间期延长；随刺激速率增加，不仅上述差异更加显著，而且Ⅲ波潜伏期、Ⅴ波振幅及Ⅰ~Ⅲ、Ⅰ~Ⅴ峰间期也表现出差异。结论有缺氧病史的早产儿在纠正胎龄足月时脑干功能仍存在异常，提高刺激速率有助于异常的检出，为更好地研究新生儿脑干功能状态及发育规律提供了新的方法。

Brainstem auditory evoked potentials to click stimuli of different rates in the preterm infants with a hypoxic history.

AbstractObjectiveTo study brainstem function at term in preterm infants who have a hypoxic history using brainstem auditory evoked potentials (BAEP) to click stimuli of different repetition rates.MethodsStudy group included 39 preterm infants (gestational age 29w~36w) with a hypoxic history.The controls were 30 preterm infants (gestational age 29w~36w) without any complication.The BAEP was recorded at the repetition rates of 21.1,51.1 and 91.1/sec for these babies between 37 to 42 weeks of postconceptional age.The latencies and amplitudes of wavesⅠ、Ⅲ、and Ⅴ and the interpeak intervals of Ⅰ~Ⅲ、Ⅲ~Ⅴ andⅠ~Ⅴ were analyzed.ResultsIn preterm infants with a hypoxic history,the latency of wave Ⅴ and Ⅲ~Ⅴ interpeak interval increased at 21.1/sec,compared with the controls.At 51.1/sec and 91.1/sec,these changes became more significant,and the latency of Ⅲ,amplitude of Ⅴ and the Ⅰ~Ⅲ、Ⅰ~Ⅴ interpeak intervals were also significantly different from the controls.ConclusionThere are some abnormalities in brainstem auditory function at term in preterm infants who have a hypoxic history.The increase in click rate can enhance the detection of BAEP abnormalities.