Prediction of poor neurological outcome in comatose survivors of cardiac arrest: a systematic review

Intensive Care Med. 2020 Oct;46(10):1803-1851. doi: 10.1007/s00134-020-06198-w. Epub 2020 Sep 11.


Purpose: To assess the ability of clinical examination, blood biomarkers, electrophysiology, or neuroimaging assessed within 7 days from return of spontaneous circulation (ROSC) to predict poor neurological outcome, defined as death, vegetative state, or severe disability (CPC 3-5) at hospital discharge/1 month or later, in comatose adult survivors from cardiac arrest (CA).

Methods: PubMed, EMBASE, Web of Science, and the Cochrane Database of Systematic Reviews (January 2013-April 2020) were searched. Sensitivity and false-positive rate (FPR) for each predictor were calculated. Due to heterogeneities in recording times, predictor thresholds, and definition of some predictors, meta-analysis was not performed.

Results: Ninety-four studies (30,200 patients) were included. Bilaterally absent pupillary or corneal reflexes after day 4 from ROSC, high blood values of neuron-specific enolase from 24 h after ROSC, absent N20 waves of short-latency somatosensory-evoked potentials (SSEPs) or unequivocal seizures on electroencephalogram (EEG) from the day of ROSC, EEG background suppression or burst-suppression from 24 h after ROSC, diffuse cerebral oedema on brain CT from 2 h after ROSC, or reduced diffusion on brain MRI at 2-5 days after ROSC had 0% FPR for poor outcome in most studies. Risk of bias assessed using the QUIPS tool was high for all predictors.

Conclusion: In comatose resuscitated patients, clinical, biochemical, neurophysiological, and radiological tests have a potential to predict poor neurological outcome with no false-positive predictions within the first week after CA. Guidelines should consider the methodological concerns and limited sensitivity for individual modalities. (PROSPERO CRD42019141169).

Keywords: Cardiac arrest; Clinical examination; Coma; Computed tomography; Diffusion magnetic resonance imaging; Neuron-specific enolase; Prognosis; Somatosensory-evoked potentials.

Publication types

  • Review
  • Systematic Review

MeSH terms

  • Adult
  • Coma / etiology
  • Evoked Potentials, Somatosensory
  • Heart Arrest* / complications
  • Heart Arrest* / therapy
  • Humans
  • Hypothermia, Induced*
  • Prognosis
  • Survivors