Following subarachnoid hemorrhage the arteries that lie in the subarachnoid space become surrounded by blood. As the red blood cells die they release their contents into the cerebrospinal fluid (CSF) that fills the subarachnoid space. One of the molecules contained in large amount in red blood cells is hemoglobin (the iron/oxygen-carrying protein that gives red blood cells their red color) which is very irritating to the smooth muscles that line the wall of the cerebral arteries. This irritation causes the smooth muscles to contract which causes the blood vessel to decrease in diameter allowing less blood flow through it. If the decrease in diameter (and blood flow reduction) is severe enough the brain will not get enough oxygen and the patient will have neurologic deficits or may even have a stroke.
Constriction of one or more of the arteries traveling through the cerebrospinal fluid-filled (subarachnoid) space around the brain following hemorrhage into the subarachnoid space (subarachnoid hemorrhage). Cerebral vasospasm can result in a decrease in blood flow to the brain sufficient that neurologic function is affected (aphasia-difficulty with speech, paresis-weakness, coma-prolonged unconsciousness). Vasospasm is treated by increasing the flow through the constricted vessels by increasing the amount of blood in the vessels (hypervolemic fluid management) and the forward pressure of the blood.
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Epidemiology:
Clinical presentation:
Pathophysiology:
Workup:
Treatment: Hyperdynamic hypervolemic therapy. Angioplasty.
figure: angiogram demonstrating vasospasm
