Respiratory arrest in subarachnoid hemorrhage.

Sudden loss of consciousness and cardiorespiratory disorders occurred in 43 of 254 patients with subarachnoid hemorrhage. Two patients had ventricular fibrillation, 37 had one or more episodes with a disturbance of respiratory rhythm that required assisted ventilation, and 4 died suddenly without recorded vital signs. Sixteen patients recovered after resuscitation. The outcome could not be predicted at an early stage from the anatomic type of hemorrhage on CT, the initial presence or absence of brainstem reflexes, or the type of cardiorespiratory disorder. Spontaneous respiration and responsiveness returned within 1 hour in all patients who recovered.