Objectives: Therapeutic hypothermia and pharmacological sedation may influence outcome prediction after cardiac arrest. The use of a multimodal approach, including clinical examination, electroencephalography, somatosensory-evoked potentials, and serum neuron-specific enolase, is recommended; however, no study examined the comparative performance of these predictors or addressed their optimal combination.
Design: Prospective cohort study.
Setting: Adult ICU of an academic hospital.
Patients: One hundred thirty-four consecutive adults treated with therapeutic hypothermia after cardiac arrest.
Measurements and Main Results: Variables related to the cardiac arrest (cardiac rhythm, time to return of spontaneous circulation), clinical examination (brainstem reflexes and myoclonus), electroencephalography reactivity during therapeutic hypothermia, somatosensory-evoked potentials, and serum neuron-specific enolase. Models to predict clinical outcome at 3 months (assessed using the Cerebral Performance Categories: 5 = death; 3–5 = poor recovery) were evaluated using ordinal logistic regressions and receiving operator characteristic curves. Seventy-two patients (54%) had a poor outcome (of whom, 62 died), and 62 had a good outcome. Multivariable ordinal logistic regression identified absence of electroencephalography reactivity (p < 0.001), incomplete recovery of brainstem reflexes in normothermia (p = 0.013), and neuron-specific enolase higher than 33 μg/L (p = 0.029), but not somatosensory-evoked potentials, as independent predictors of poor outcome. The combination of clinical examination, electroencephalography reactivity, and neuron-specific enolase yielded the best predictive performance (receiving operator characteristic areas: 0.89 for mortality and 0.88 for poor outcome), with 100% positive predictive value. Addition of somatosensory-evoked potentials to this model did not improve prognostic accuracy.
Conclusions: Combination of clinical examination, electroencephalography reactivity, and serum neuron-specific enolase offers the best outcome predictive performance for prognostication of early postanoxic coma, whereas somatosensory-evoked potentials do not add any complementary information. Although prognostication of poor outcome seems excellent, future studies are needed to further improve prediction of good prognosis, which still remains inaccurate.
1Department of Intensive Care Medicine, CHUV-Lausanne University Hospital and Faculty of Biology and Medicine, Lausanne, Switzerland.
2Department of Clinical Neurosciences, CHUV-Lausanne University Hospital and Faculty of Biology and Medicine, Lausanne, Switzerland.
* See also p. 1535.
Dr. Oddo conceived and designed the study; drafted and revised the manuscript; and analyzed, interpreted, and acquired the data. Dr. Rossetti conceived and designed the study; drafted and revised the manuscript; analyzed, interpreted, and acquired the data; did statistical analysis; and coordinated the study.
Dr. Oddo received support for article research from Swiss National Science Foundation (grant 320030_138191). He consulted for Bard Medical Integra Neurosciences and lectured for Bard Medical Integra Neurosciences. His institution received grant support from the Swiss National Science Foundation. Dr. Rossetti and his institution received support from Swiss National Science Foundation (grant CR32I3_143780).
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