Neurologic Outcomes After Cardiac Arrest

Patients in a coma less than 12 hours after resuscitation usually make a favorable recovery. Comas lasting more than 12 hours often have neurologic deficits due to focal or multifocal infarcts of the cerebral cortex.

Somatosensory evoked potentials (SEPs) have the highest prognostic reliability and are the most frequently applied method in clinical and experimental studies evaluating outcome after CPR. Bilateral absence of median nerve-stimulated SEPs is associated with a <1% chance of awakening from coma since it implies that widespread cortical necrosis has occurred. Importantly, the presence of cortical responses is not a guarantee for awakening from coma.

Absence of pupillary responses on the first day or absence of corneal reflexes after the first day following CPR predicts poor outcome. If there are no purposeful motor responses after 3 days, there is a high risk of persistent vegetative state or severe disability.

Verbal responses, purposeful eye movements or motor responses, normal ocular reflexes, and response to verbal commands at 1 day following CPR predict at least a 50% chance of regaining independent function. Patient age, gender, or presence of postanoxic seizure failed to correlate with outcome.