Department of Intensive Care, Room C3-423, Academic Medical Centre, P.O. Box 22660, 1100 DD, Amsterdam, The Netherlands.
J Neurol. 2012 Mar;259(3):537-41. doi: 10.1007/s00415-011-6224-5. Epub 2011 Sep 2.
Bilateral absence of cortical N20 responses of median nerve somatosensory evoked potentials (SEP) predicts poor neurological outcome in postanoxic coma after cardiopulmonary resuscitation (CPR). Although SEP is easy to perform and available in most hospitals, it is worthwhile to know how neurological signs are associated with SEP results. The aim of this study was to investigate whether specific clinical neurological signs are associated with either an absent or a present median nerve SEP in patients after CPR. Data from the previously published multicenter prospective cohort study PROPAC (prognosis in postanoxic coma, 2000-2003) were used. Neurological examination, consisting of Glasgow Coma Score (GCS) and brain stem reflexes, and SEP were performed 24, 48, and 72 h after CPR. Positive predictive values for predicting absent and present SEP, as well as diagnostic accuracy were calculated. Data of 407 patients were included. Of the 781 SEPs performed, N20 s were present in 401, bilaterally absent in 299, and 81 SEPs were technically undeterminable. The highest positive predictive values (0.63-0.91) for an absent SEP were found for absent pupillary light responses. The highest positive predictive values (0.71-0.83) for a present SEP were found for motor scores of withdrawal to painful stimuli or better. Multivariate analyses showed a fair diagnostic accuracy (0.78) for neurological examination in predicting an absent or present SEP at 48 or 72 h after CPR. This study shows that neurological examination cannot reliably predict absent or present cortical N20 responses in median nerve SEPs in patients after CPR.
双侧正中神经体感诱发电位（SEP）皮质 N20 反应缺失预示心肺复苏（CPR）后缺氧性昏迷患者的神经预后不良。尽管 SEP 易于进行，且大多数医院都可开展，但了解神经体征与 SEP 结果的关系仍然很有价值。本研究旨在调查 CPR 后患者的特定临床神经体征是否与正中神经 SEP 的缺失或存在相关。研究数据来自先前发表的多中心前瞻性队列研究 PROPAC（缺氧性昏迷预后，2000-2003 年）。在 CPR 后 24、48 和 72 小时进行了神经检查，包括格拉斯哥昏迷评分（GCS）和脑干反射，以及 SEP。计算了预测缺失和存在 SEP 的阳性预测值以及诊断准确性。共纳入 407 例患者。在进行的 781 次 SEP 中，401 次存在 N20 波，299 次双侧缺失，81 次 SEP 因技术原因无法确定。对于预测缺失 SEP，瞳孔对光反射缺失的阳性预测值最高（0.63-0.91）。对于预测存在 SEP，对于对疼痛刺激有退缩反应或更好的运动评分，阳性预测值最高（0.71-0.83）。多变量分析显示，在 CPR 后 48 或 72 小时，神经检查对预测缺失或存在 SEP 的诊断准确性为中等（0.78）。本研究表明，神经检查不能可靠地预测 CPR 后患者正中神经 SEP 中皮质 N20 反应的缺失或存在。
