Prognostic determination of patients in coma after resuscitation from cardiac arrest is a common and difficult requirement with significant ethical, social and legal implications. We set out to seek markers that can be used for the early detection of patients with a poor prognosis, so as to reduce uncertainty over treatment and non-treatment decisions, and to improve relationships with families. We reviewed the medical literature from 1991 to 2010, using key words such as post-anoxic coma, post-anoxic vegetative state, vegetative state prognosis, recovery after cardiac arrest. Neurological examination, electrophysiology, imaging, and biochemical markers are all useful tools for estimating patients' chances of recovery from cardiac arrest. It seems unlikely that any single test will prove to have 100% predictive value for outcome; but the combination of various prognostic markers, as shown in some articles, could increase the reliability of outcome prediction. However, further research is needed.