A stroke is what happens when the blood flow to the brain is interrupted. Up to 1.9 million brain cells die every minute during a stroke.
Depending on which part of the brain is impacted, a stroke can affect speech, emotions, sensations, vision, and even vital functions such as the heart, ability to swallow, and breathing.
Contrary to popular belief, a stroke can occur at any age or gender, although there are definite risk factors. In order to consider an individual’s risk we need to understand what can cause stroke.
What Causes a Stroke?
There are two main causes of stroke: from a bleed (haemorrhage) and from a blockage (from blocked arteries or a blood clot causing ischaemic stroke).
This is when there is a leak or burst blood vessel. When an artery deep inside the brain bursts, this is known as an intracerebral haemorrhage and is typically the result of high blood pressure.
If the bleed occurs on the surface of the brain, or specifically between the first and second layer of the brain, this is known as a subarachnoid haemorrhage.
The cause of brain haemorrhages is very often related to either hypertension (high blood pressure) or aneurysms, meaning there is a thin part of the blood vessel that balloons over time. The balloon can burst as a result of high blood pressure or a head trauma.
An ischaemic stroke is where a blood clot stops blood flowing into, or within, the brain. There are two main types: embolic and thrombotic.
Embolic strokes: Blood clots can sometimes begin in the heart or another area of the body and travel to the brain. Once inside the brain, the clot may be too thick to travel and cause a restriction of blood flow.
Thrombotic strokes: Blocked arteries can also cause stroke by restricting the flow of blood to the brain. These can be the result of cholesterol-laden plaques that stick to the wall of the artery and, over time, block the passage of oxygen and nutrients. These blockages often build up in the neck.
Other Stroke Risks
Venous Thromboembolisms (VTE)
Long periods of immobility can pose a health risk concerning the veins deep inside the body.
Being sedentary for too long can exacerbate this risk. For stationary travellers, if a clot is formed in the legs it can move and cause heart attack. The clot could also lodge into the lung and cause a pulmonary embolism, or if it got caught in a cerebral artery, it can cause a stroke.
Long plane trips, as well as long periods in transit, such as experienced by truck drivers and commuters, need special attention. People who spend long periods of time seated at a desk would be advised to consider a standing desk or to implement more activity into their day.
Those who have already had a stroke are at increased risk of DVT as are those who have recently had surgery, are pregnant, are using oral contraceptives, those over 40 years of age also have a higher risk.
About half of all episodes of deep vein thrombosis have no signals. If there are, they may include:
- Changes in skin colour (redness)
- Leg pain or tenderness, especially in the calf
- Skin feels warm to the touch
Transient Ischaemic Attacks (TIA)
This is when the blood supply in the brain is stopped temporarily. When the blood supply is returned, some effects may pass. However, this does not mean that no damage has been done. A transient ischaemic attack is a serious event that will often presage another stroke, which can lead to disability or death. Treatment should be undertaken immediately and precautions made to prevent further episodes.
Signs and Symptoms of Stroke
The signs of stroke or TIA can differ depending on the part of the brain affected.
Generally, these are common things to be aware of:
- Numbness or weakness
- Dizziness or loss of balance
- Sudden headaches
- Paralysis (including parts of the face)
A brain scan (either CT or MRI) will generally be required to determine the type and location of the stroke event. After that, it is often important to regularly monitor and maintain a healthy-range blood pressure.
It may be important to also conduct heart tests for atrial fibrillation, which can cause an embolic stroke. Atrial fibrillation is where the heart beats out of rhythm. Blood is not pumped smoothly and often blood is not completely pumped out. This can result in a blood clot forming in the heart, which can then travel to the brain and cause an embolism.
While it is true that stroke can occur to anyone of any age, there are some groups at higher risk than others. Heart disease and blood pressure make up significant risk factors. Diabetes is another risk factor, as is high cholesterol. Generally speaking, good health that includes a healthy diet and exercise regime will reduce the risk of stroke.
Up to 1.9 million brain cells die every minute during a stroke.
Point of Care Tests
If a person has suffered a TIA or has had a stroke, there are a number of point of care tests and diagnostic tools that may help manage ongoing health.
People who are currently at risk of developing a life-threatening blood clot may be given an anti-coagulant therapy, such as warfarin, heparin, or similar. To measure the effectiveness of this therapy, regular tests to measure the Prothrombin Time (PT) will be conducted. The PT test is a measure of the time it takes the blood to clot and is used to determine if the dose of blood-thinning medication is correct.
The micoINR device is available for individuals and practitioners to deliver fast and accurate PT test results with a 3 microlitre capillary sample of blood obtained by fingerprick.
For a person who is not taking anticoagulation medication a normal INR reading would be 1. The higher the INR value, the longer it takes for the blood to clot. Likewise, the lower the reading, the higher the risk of bruising and dangerous bleeding.
The handheld CardioChek PA analyser is quick and convenient to use. It is a cost-effective, user-friendly diagnostic point-of-care analyser, which uses test strips to accurately measure cholesterol, HDL, LDL and triglyceride (lipid) levels.
Using a fingerprick 15 microlitre capillary blood sample, the test takes about 90 seconds. If you are a clinician the reading can be performed with a patient in front of you. Management advice can be given alongside a lab-quality result in the same session.
Blood pressure monitors
High blood pressure is an extremely serious risk factor. Encouraging people with high blood pressure to exercise and eat sensibly, as well as to regularly monitor their own blood, will help reduce the risk of further stroke and provide a level of control.
There are a number of handy, inexpensive blood pressure monitors that are easy to use with no special training required.
People who have diabetes are at increased risk of stroke. Those with type 1 diabetes need to check their blood sugar levels. If people with type 1 diabetes do not have continuous glucose monitoring device, it is recommended that they manually do a blood sugar test at least four times per day.
People who have type 2 diabetes are also recommended to take regular readings of their HbA1c. This small and handheld analyser provides step-by-step instructions on obtaining high-quality HbA1c test results on the spot. This is a point of care device that a diabetes educator or clinical practitioner can use in a treatment room.
Strokes can have a damaging or fatal impact on brains. While there are excellent advancements in stroke rehabilitation, the best management may be prevention. There is much that can be done by clinicians at the point of care. The best care may be in the form of patient education and monitoring of heart and blood pressure, cholesterol, and effective diabetes management.
References and Further Reading