Department of Neurology, University Hospital and Faculty of Biology and Medicine, Lausanne, Switzerland.
Ann Neurol. 2010 Mar;67(3):301-7. doi: 10.1002/ana.21984.
Current American Academy of Neurology (AAN) guidelines for outcome prediction in comatose survivors of cardiac arrest (CA) have been validated before the therapeutic hypothermia era (TH). We undertook this study to verify the prognostic value of clinical and electrophysiological variables in the TH setting.
A total of 111 consecutive comatose survivors of CA treated with TH were prospectively studied over a 3-year period. Neurological examination, electroencephalography (EEG), and somatosensory evoked potentials (SSEP) were performed immediately after TH, at normothermia and off sedation. Neurological recovery was assessed at 3 to 6 months, using Cerebral Performance Categories (CPC).
Three clinical variables, assessed within 72 hours after CA, showed higher false-positive mortality predictions as compared with the AAN guidelines: incomplete brainstem reflexes recovery (4% vs 0%), myoclonus (7% vs 0%), and absent motor response to pain (24% vs 0%). Furthermore, unreactive EEG background was incompatible with good long-term neurological recovery (CPC 1-2) and strongly associated with in-hospital mortality (adjusted odds ratio for death, 15.4; 95% confidence interval, 3.3-71.9). The presence of at least 2 independent predictors out of 4 (incomplete brainstem reflexes, myoclonus, unreactive EEG, and absent cortical SSEP) accurately predicted poor long-term neurological recovery (positive predictive value = 1.00); EEG reactivity significantly improved the prognostication.
Our data show that TH may modify outcome prediction after CA, implying that some clinical features should be interpreted with more caution in this setting as compared with the AAN guidelines. EEG background reactivity is useful in determining the prognosis after CA treated with TH.
当前美国神经病学学会（AAN）关于心脏骤停（CA）昏迷幸存者预后预测的指南是在治疗性低温（TH）时代之前验证的。我们进行这项研究是为了验证在 TH 环境下临床和电生理变量的预后价值。
在 3 年期间，前瞻性研究了 111 例连续接受 TH 治疗的 CA 昏迷幸存者。在 TH 后、体温正常和停用镇静剂时进行神经检查、脑电图（EEG）和体感诱发电位（SSEP）。在 3 至 6 个月时使用脑功能分类（CPC）评估神经恢复情况。
与 AAN 指南相比，CA 后 72 小时内评估的 3 个临床变量显示出更高的假阳性死亡率预测：不完全脑干反射恢复（4%比 0%）、肌阵挛（7%比 0%）和无疼痛运动反应（24%比 0%）。此外，无反应的 EEG 背景与长期良好的神经恢复不相容，与住院死亡率强烈相关（死亡调整优势比，15.4；95%置信区间，3.3-71.9）。4 个独立预测因素（不完全脑干反射、肌阵挛、无反应的 EEG 和无皮质 SSEP）中的至少 2 个存在准确地预测了长期不良神经恢复（阳性预测值=1.00）；EEG 反应性显著改善了预后。
我们的数据表明，TH 可能会改变 CA 后的预后预测，这意味着与 AAN 指南相比，在这种情况下某些临床特征的解释应更加谨慎。EEG 背景反应性可用于确定接受 TH 治疗的 CA 后的预后。
