None listed
Conditions
Brief summary
In ischaemic stroke (caused by a blocked blood vessel) a region of the brain is starved of oxygen, and dies. There is a window of opportunity to restore blood flow to prevent tissue death, even small increases in blood flow can lengthen this window. Only unblocking blocked arteries by clot dissolving medication or sucking the clot out directly are proven therapies. We propose that using Metaraminol to boost blood pressure will improve blood flow to the brain as a bridging method until definitive treatment restores blood flow. We aim to prove this approach using advanced brain imaging called CT perfusion, which can effectively detect the size and region of brain tissue at threat of dying without blood flow restoration. Stroke patients are usually managed without blood pressure support, but if our research is positive, this practice could be altered, especially in long distance stroke retrievals.
Interventions
Patients who meet trial inclusion criteria (hemispheric stroke symptoms with initial blood pressure below 160mmHg on presentation) will be consented for blood pressure augmentation with Metaraminol prior to definitive intervention for acute ischaemic stroke.
After initial multimodal CT perfusion imaging, blood pressure is measured every 90 secondly with bolus intravenous metaraminol administration via 'chooks foot' infusion device, aiming for systolic blood pressure (sBP) of 160-180mmHg.
If sB
Patients who meet trial inclusion criteria (hemispheric stroke symptoms with initial blood pressure below 160mmHg on presentation) will be consented for blood pressure augmentation with Metaraminol prior to definitive intervention for acute ischaemic stroke. After initial multimodal CT perfusion imaging, blood pressure is measured every 90 secondly with bolus intravenous metaraminol administration via 'chooks foot' infusion device, aiming for systolic blood pressure (sBP) of 160-180mmHg. If sBP is 150-159mmHg, 0.1mg of intravenous bolus metaraminol is administered If sBP is 130-149mmHg, 0.15mg of intravenous bolus metaraminol is administered If sBP is 110-129mmHg, 0.25mg of intravenous bolus metaraminol is administered If sBP is less than 110mmHg, 0.5mg of intravenous bolus metaraminol is administered Metaraminol will be administered every 90 seconds for a maximum of 7.5 minutes or until target sBP is reached. Intravenous Labetalol will be administered at 5-10mg bolus doses if sBP is above target range as determined by planned intervention. The maximum total labetalol dose administered will depend on patient heart rate and tolerability of labetalol. Repeat CT perfusion imaging is performed after 7.5 minutes of blood pressure augmentation with metaraminol and blood pressure measurement. Repeat NIHSS (National Institutes of Health Stroke Scale) is performed after completion of CT perfusion imaging.
Sponsors
Royal Adelaide Hospital
Study design
Allocation
Non-randomised trial
Primary purpose
Treatment
Eligibility
Sex/Gender
All
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
1) Acute anterior circulation ischaemic stroke with measurable neurologic deficit 2) Demonstration of penumbra of CT perfusion imaging (Delay time (DT) lesion >3 seconds volume > 30 mL, as measured by MiSTAR software) 3) Initial systolic blood pressure on ED presentation below 160mmHg
Exclusion criteria
1) Known renal failure (eGFR < 30mL) 2) Iodine contrast hypersensitivity 3) Any contraindication to Metaraminol administration ((hypersensitivity to Metaraminol including sulfite allergy, nonselective Monoamine Oxidase Inhibitor (MAO-I) therapy (phenelzine, tranylcypromine) in the past 14 days)) 4) <50 years old 5) Previous intracerebral or subarachnoid haemorrhage 6) Presence of an intracranial aneurysm or arteriovenous malformation 7) Presence of an aortic dissection 8) Presence of an acute or recent (<30 days) myocardial infarction 9) Recent (<1 month) left ventricular failure 10) Any other condition which, in the opinion of the Investigator, increases the risk of blood pressure augmentation
Outcome results
None listed