The natural course of neurological recovery following cardiopulmonary resuscitation.

In 231 patients resuscitated from circulatory arrest of cardiovascular or pulmonary aetiology brain recovery was evaluated by serial neurological and EEG examinations for up to 1 year. One-hundred and sixteen patients never regained consciousness; 115 patients awakened within 30 days, and 40 eventually recovered completely within 90 days. Patients who had electrocortical activity recorded by the immediate post-resuscitation EEG (N = 106), and patients initially without such activity (N=125) pursued the same course of recovery: during unconsciousness, interrelated EEG and neurological findings featured a phase of intermittent cortical activity with postural or stereotypic motor responses followed by a phase of continuous cortical activity with sequential appearances of delta, theta, and alpha activities on EEG accompanied by stereotypic or defensive motor responses.