Sildenafil for DCI
Sildenafil for DCI
Each year, approximately 30,000 people in the United States suffer an intra-cranial
 hemorrhage due to aneurysmal rupture. Of those surviving the initial event, up to 40% will go
 on to have further neurological injury secondary to stroke (delayed cerebral ischemia) caused
 by constriction of blood vessels (i.e. vasospasm). Previous studies have shown that the
 medication sildenafil, given intravenously, improves vasospasm, but has an associated degree
 of hypotension. The degree of hypotension was well within safety thresholds for these
 patients.

 Sildenafil is a medication that strongly inhibits the protein phosphodiesterase-V (PDE-V).
 The hypothesis for this study is that oral sildenafil will also improve vasospasm, but does
 not result in as much hypotension. Specifically, the investigators look to show that
 comparable doses of oral sildenafil produces the same degree of PDE-V inhibition as an
 intravenous dose while the degree of hypotension is reduced. Additionally, using measurements
 of cerebral blood flow regulation acquired using transcranial Doppler ultrasound, the
 investigators look to show that oral sildenafil produces the same degree of improvement in
 vasospasm and blood flow regulation.
Inclusion Criteria:

 1. Age >= 21

 2. Onset of symptoms within 72 hours from presentation

 3. Subarachnoid hemorrhage from ruptured cerebral aneurysm

 4. Cerebral vasospasm diagnosed on transcranial doppler, CT angiography, or digital
 subtraction angiography

 Exclusion Criteria:

 1. Pregnancy

 2. Subarachnoid hemorrhage secondary to traumatic or mycotic aneurysm

 3. Pre-ictal sildenafil therapy (last dose within 1 week of presentation)

 4. Contraindications to sildenafil therapy (i.e. use of nitrates, left ventricular
 outflow obstruction, impaired autonomic blood pressure control)