甘露醇干预对闪光视觉诱发电位影响的研究

Effect of administration of mannitol on flash visual evoked potentials

目的探讨甘露醇应用前后闪光视觉诱发电位(fVEP)N2波的变化趋势及其与颅内压变化之间的关系。方法选择52例高颅压患者,将其分为单用甘露醇组和合用甘油氯化钠组,两组分别为32例及20例。应用NIP-200型无创颅内压监测仪测定第1、4、10次应用甘露醇前后fVEP N2波潜伏期及波幅,并进行比较。结果单用甘露醇组甘露醇应用后30 m in N2波潜伏期开始缩短,在应用后2 h时缩至最短,4 h时N2波潜伏期有所回升,但仍较甘露醇应用前短。N2波波幅差异无统计学意义。随着甘露醇应用次数的增多,N2波潜伏期缩短的程度逐渐降低。合用甘油氯化钠降颅压组甘露醇应用前后N2波潜伏期变化不明显。结论甘露醇应用前后fVEP N2波潜伏期发生了变化,提示fVEP N2波潜伏期的变化可以反映颅内压的变化趋势。

Objective To study the relationship between the changes in N2 wave of flash visual evoked potential （fVEP） and the intracranial pressure after the administration of mannitol. Methods Fiftytwo patients with elevated intracranial pressure, 28 males and 24 females, aged 49 ± 18, were divided into two groups： mannitol group （ n = 32, treated with intravenous drip of mannitol 2 - 3 times/day） and mannitol ＋ glycerol and sodium chloride group （n = 20, treated with intravenous drip of mannitol 2 - 3 times/day and glycerol and sodium chloride once every evening）. NIP-200 noninvasive intraeranial pressure apparatus was used to measure the latency and amplitude of N2 wave of fVEP before and after the 1st, 4 th, and 10 th administration of mannitol. Results In the mannitol group, the latency of N2 wave began to reduce 30 min after the injection of mannitol and was the lowest 2 hours after the administration of mannitol. Four hours after the injection of mannitol, the latency of N2 wave increased, however, was still shorter than that before the injection of mannitol （ P 〈 0. 05 ） ; the extent of reduction of the latency of N2 wave was 40 ± 2 ms, as the greatest reduction ; and began to be reduced since the 4th injection, as 38 ± 2 ms, however, not significantly different from that of the first reduction （P 〉 0.05 ）; and the extent of reduction of the latency of N2 wave after the 10th injection was 29 ± 2 ms, significantly different from that after the first injection （P 〈0. 05）. There was no significant difference in the amplitude of N2 wave between the 2 groups. The latency of the N2 wave of fVEP was slightly, but not significantly, after the 4 th and 10 th administration of mannitol in the mannitol ＋ glycerol and sodium chloride group. The latency of the N2 wave of fVEP reduced rapidly and continuously in the patients with toxic eneephalopathy and meningitis, and the latency of the N2 wave reduced rapidly after the first administration of marmitol, however, the extent of reduction was reduced along with the frequency of mannitol administration. Conclusion The latency of N2 wave of fVEP changes after the administration of mannitol, suggesting that the change of the latency of N2 wave of fVEP reflects the change of intracranial pressure.