Cerebral circulation after cardiac arrest. Microangiographic and protein tracer studies

The effects of ventricular fibrillation and subsequent resuscitation on the microcirculation of the verebral cortex were studied with microangiographic and fluorescent protein tracer techniques. Immediately after revival, a transient period of impaired cerebral perfusion occurred before complete recovery from circulatory arrest was obtained. A circulatory arrest of longer than ten minutes, followed by four to six hours of resuscitation, caused defects of cortical capillary filling in both microangiography and Trypan blue fluorescence. This was considered to represent impairment of cortical perfusion, most likely due to edema. Cardiac arrest up to 12 minutes and subsequent resuscitation per se caused no blood-brain barrier damage. Minimal blood-brain barrier damage occurred in one dog following uncomplicated revival from a 14-minute arrest and in animals with prolonged hypertension post-resuscitation. Up to three consecutive carotid angiographies did not cause blood-brain barrier damage in the postischemic brain.