重型颅脑损伤长期意识障碍患者的体感诱发电位分级研究及预后评估

Evaluation of SEP grading and prognosis of severe TBI patients in long-term unconscious state

目的探讨体感诱发电位(SEP)对重型颅脑损伤(TBI)后长期意识障碍患者清醒预测的分级标准;研究其清醒预测及生存预后的评估。方法记录46例重度颅脑损伤后意识障碍>1周的患者以进行清醒预测,选择6个预后因子即年龄、性别、受伤机制、手术与否、SEP表现方式、清醒所需时间等对预后进行分析。SEP中以N20-P25存在与否将SEP分为3级:Ⅰ级,双侧N20-P25都存在;Ⅰa双侧中枢传导时间(CCT)正常且对称;Ⅰb双侧CCT正常,但不对称;Ⅱ级,一侧N20-P25存在,另一侧消失;Ⅲ级,双侧N20-P25都消失。预后以外伤后6个月患者是否清醒为标准。结果 SEP分级与清醒的概率及格拉斯哥预后评分(GOS)有显著相关性(P<0.05),分级越高,预后越差。昏迷时间越长,预后越差。对清醒预测的敏感性为80.77%,特异性为75%,准确率为78.26%,错误率为10.87%。结论 SEP的分级可客观、准确地反映脑功能损伤程度和清醒的机会。

Objective To evaluate the consciousness prediction of somatosensory evoked potentials in（SEP） patients with severe traumatic brain injury（TBI）.Methods A consecutive sample of 46 patients after severe TBI with disturbance of unconsciousness 1 week from Jan.2001 to Aug.2008 were recorded.Six prognostic factors including age,gender,operation,mechanism of injury,classification of SEP,duration of unconsciousness and history of temporal craniectomy were selected and analyzed in the 46 cases.The SEP was classified into 3 grades according to the presence of N20-P25 wave.GradeⅠ： bilateral N20 waves existed,（1）bilateral N20 waves were normal and symmetrical;（2）bilateral N20 waves were normal but asymmetrical.GradeⅡ： unilateral N20 wave existed,the other side disappeared.Grade Ⅲ： bilateral N20 waves disappeared.The prognosis of outcome was judged by Glasgow Outcome Scale（COS）.Results Classification of SEP had significant correlation with the probabilities of awakening and the Glasgow Outcome Scale（P〈0.05）.The SEP grade was negatively related with the probabilities of consciousness and the GOS.The other factors including age,gender were excluded（P〉0.05）.Duration of unconsciousness was not correlated with these factors like gender,age,mechanism of injury,classification of somatosensory evoked potentials as well as history of temporal craniectomy.The accuracy of predicting the outcome of consciousness was 78.26%,the sensitivity and the specificity was 80.77% and 75%,respectively.Conclusion The classification of SEP grading can objectively and accurately demonstrate the outcome of unconscious patients and probabilities of their consciousness.