Sherman A L, Tirschwell D L, Micklesen P J, Longstreth W T, Robinson L R
Department of Rehabilitation Medicine, University of Washington, Seattle, USA.
Neurology. 2000 Feb 22;54(4):889-94. doi: 10.1212/wnl.54.4.889.
To examine the utility of somatosensory evoked potential (SEP) peaks and CSF creatine kinase BB isoenzyme activity (CKBB) in predicting nonawakening from coma due to cardiac arrest.
Accurate predictors of neurologic outcome in patients comatose after cardiac arrest are needed to improve medical decision making.
A total of 72 comatose patients had bilateral median SEPs, and of these, 52 had CSF and CKBB. Awakening was defined as following commands or having comprehensible speech. Both short (N1) and long (N3) latency SEP peaks were analyzed. Nonparametric analyses were used.
For patients who had both tests, CKBB > or = 205 U/L predicted nonawakening with a sensitivity of 49% and a specificity of 100%. Bilateral absence of the N1 peak predicted nonawakening with a sensitivity of 53% and a specificity of 100%. Using CKBB > or = 205 U/L, bilaterally absent SEP N1 peaks, or both predicted nonawakening with a sensitivity of 69% and a specificity of 100%. Using CKBB > or = 205 U/L, bilaterally absent N1 peaks, bilateral N3 > or = 176 msec or absent, or some combination predicted nonawakening with a sensitivity of 78% and a specificity of 100%.
The combination of an absent N1 peak and elevated CKBB performs better than either alone in predicting nonawakening after cardiac arrest. Prolonged or absent N3 latency may increase sensitivity. These results should be interpreted with caution given the small number of patients and the possibility of a self-fulfilling prophecy.
探讨体感诱发电位（SEP）峰和脑脊液肌酸激酶BB同工酶活性（CKBB）在预测心脏骤停所致昏迷患者不能苏醒方面的作用。
心脏骤停后昏迷患者的神经功能预后需要准确的预测指标，以改善医疗决策。
共72例昏迷患者接受双侧正中神经SEP检查，其中52例患者同时进行了脑脊液和CKBB检测。苏醒定义为能听从指令或有可理解的言语。分析了短潜伏期（N1）和长潜伏期（N3）SEP峰。采用非参数分析。
对于两项检查均进行的患者，CKBB≥205 U/L预测不能苏醒的敏感度为49%，特异度为100%。双侧N1峰缺失预测不能苏醒的敏感度为53%，特异度为100%。使用CKBB≥205 U/L、双侧SEP N1峰缺失或两者联合预测不能苏醒的敏感度为69%，特异度为100%。使用CKBB≥205 U/L、双侧N1峰缺失、双侧N3≥176毫秒或缺失，或某些组合预测不能苏醒的敏感度为78%，特异度为100%。
在预测心脏骤停后不能苏醒方面，N1峰缺失和CKBB升高联合应用比单独使用其中任何一项表现更好。N3潜伏期延长或缺失可能会提高敏感度。鉴于患者数量较少以及存在自我实现预言的可能性，这些结果应谨慎解读。
