Induced Hypertension for Acute Ischemic Stroke

Inclusion Criteria: Patients with acute ischemic stroke in whom treatment can be initiated within 12 hours of a clearly defined symptom onset. (If the patient awakens with a deficit, time of onset is considered the time the patient was last seen functioning normally.) Age older then 18 years of age. Measurable neurologic deficit other than isolated facial weakness, sensory loss or ataxia. NIHSS must be > 4 points. Head CT showing no evidence of intracranial hemorrhage or mass lesion which might increase the risk of bleeding. Absence of ischemic changes on EKG (i.e. > than 1mm ST segment elevation or depression in at least two contiguous leads, new T waves inversion in two leads). No contraindication to MRI studies, including allergy to gadolinium. Exclusion Criteria: History of unstable angina, any recent angina (defined as chest pain) in the past 3 months, recent myocardial infarction (less then 3 months), any history of ventricular arrhythmia, presence of left ventricular bundle branch block on EKG. History of severe and symptomatic cardiac valvular disease. History of congestive heart failure, dilated cardiomyopathy, hypertrophic obstructive cardiomyopathy, or known ejection fraction < 25%. Systolic blood pressure greater > 200 mm Hg or MAP > 120 mm HG when patient is initially monitored. Serum creatinine greater then 2 mg/dl. History of symptomatic peripheral vascular disease or Raynaud's syndrome. Suspected seizure at the onset of stroke. Treatment with IV tPA or other thrombolytic agent. Massive stroke (> 2/3 MCA territory) or any amount of midline shift due to cerebral edema on head CT. Pregnancy Current use of MAO inhibitors, tricyclic antidepressant medications, or cyclopropane or halothane anesthetic agents. Coma. Allergies or known contraindications to the use of IV phenylephrine, IV norepinephrine, sodium metabisulfite, or oral midodrine. Hemorrhage on initial MRI or CT or other structural lesion that might raise the risk of intracranial bleeding. Thrombocytopenia (plt < 100 k), PTT > 100 sec, INR > 3.0 at time of treatment. Participation in other investigational trial within 30 days. Moderate to severe baseline disability (pre-stroke Rankin score of > 3), severe or terminal concurrent medical illness with expected survival of < 3 months, or other concurrent medical or psychiatric condition which may limit neurologic assessment or patient follow-up in the opinion of the investigator. Requirement for anticoagulation with IV heparin or warfarin in the first 48 hours after enrollment. Inability or unwillingness of subject or legal guardian/representative to give written informed consent. Toxicology screen positive for cocaine. Intubated at time of enrollment. Mesenteric or peripheral vascular thrombosis. Profound hypoxia or hypercarbia as defined as a PaO2 level less than 50 or a PaCO2 level of greater than 60. Norepinephrine Exclusion Criteria- The patient will not receive Norepinephrine if the patient has any of the following: lack of sufficient vascular access (central line or peripheral line greater than 18 gauge is sufficient), hypersensitivity to norepinephrine products, severe hypertension as in 4.2.4 above, tachycardia defined as HR >100 for 10 minutes sustained, myocardial infarction, pulmonary edema, peripheral ischemia, or ventricular arrhythmias.