Severe anemia associated with transient ischemic attacks involving vertebrobasilar circulation.

Transient ischemic attack is one of the most common causes of transient neurologic deficit. Anemic hypoxia results from reduced hemoglobin content with normal arterial oxygen tension and saturation. Anemic hypoxia caused by blood loss or hemolysis has not been considered as an independent factor leading to significant neurologic problems because cerebral homeostasis adjusted by the physiologic regulation in cerebral hemodynamics and oxygenation would meet the brain oxygen requirement in most circumstances even with profound anemia. We report a case of severe anemia associated with transient ischemic attack involving vertebrobasilar circulation.