Paramedic Initiated Lisinopril For Acute Stroke Treatment

High blood pressure immediately following stroke is common and related to poorer stroke functional outcome and death. Although treatment of high blood pressure is well established for thre prevention of stroke, it is unclear if high blood pressure observed immediately after stroke should be lowered.

Several previous clinical trials have lowered blood pressure in acute stroke but this has not resulted in improved stroke outcome. One reason for this may be because treatment was started too late after stroke occurred. There is rapid progression of brain injury following stroke and any stroke treatment may need to be started very early to have a beneficial effect. Previous trials started blood pressure lowering after patients arrived at hospital and this was usually a significant time after stroke occurred.

The earliest time after stroke that blood pressure treatment could be started is during contact with the emergency medical services (paramedics). This research study is a pilot double blind randomised controlled trial of paramedic initiated blood pressure treatment for patients with high blood pressure immediately after stroke.

Patients with high blood pressure and suspected acute stroke will be identified and offered the opportunity to participate in the study by research trained paramedics from the North East Ambulance Service NHS Trust. Patients who agree to participate in the study will receive either lisinopril (a common blood pressure lowering medication) or 'dummy' (placebo) treatments for seven days. The first dose of medication will be given by the paramedic in the ambulance. Subsequent tablets will be given in hospital. The effects of treatment will be monitored by measuring blood pressure, neurological outcome and adverse events.

All aspects of study feasibility including recruitment rates and compliance with data collection will be recorded. The study will run for one year and recruit 60 patients.

Inclusion criteria

• Adults ≥ 40 years old
• New unilateral arm weakness thought to be due to acute stroke within 3 hours of symptom onset
• Hypertension as defined by systolic BP >160mm Hg on two consecutive seated or lying readings taken 5 - 10 minutes apart
• Conscious (eyes open spontaneously ie "A" on Alert, Voice, Pain, Unresponsive (AVPU) scale)
• Patient being transported to a PIL-FAST trial site (i.e. Royal Victoria Infirmary, North Tyneside General Hospital and Wansbeck General Hospital)
• Verbal consent obtained from participant or next of kin

Exclusion criteria

• Age < 40 years
• Females who are pregnant, lactating or at risk of pregnancy (i.e. who are not surgically sterile or at least 1 year post last menstrual period). Females < 56 years of age consented by a relative will be excluded as menstrual history may be unknown.
• Any presentation of suspected stroke without unilateral arm weakness
• Cannot establish that stroke onset time (i.e. when patient was last seen well without symptoms) was within the last 3 hours
• Systolic BP < 160mm Hg
• Reduced level of consciousness (below "A" on AVPU scale)
• Patient not being transported to PIL-FAST trial site
• Absence of participant or next of kin consent
• Known to be taking ACE-inhibitor or Angiotensin II Receptor Blocker medication already
• Known sensitivity to lisinopril or other ACE-inhibitor medication
• Pulse > 120 beats per minute
• Seizure activity in this illness episode (witnessed or history)
• Hypoglycaemia (blood glucose < 3.5 mmols/l)
• Cannot walk independently prior to stroke (walking stick / frame is allowed)
• Obvious understanding or memory problems when next of kin is absent
• Significant head trauma or brain surgery in the last 3 months
• Known renal failure
• Known liver failure (or currently jaundiced)
• Uncontrolled heart failure (breathlessness at rest)
• Receiving palliative care for known malignancy
• Currently enrolled in a clinical trial assessing a study drug