A brain injury occurring as the result of some kind of interference with blood flow within the brain.
Causes of Stroke
The brain relies on a constant flow of oxygen-rich blood via the carotid arteries in the sides of the neck and the vertebral arteries up the back of the neck. Disruption, even for seconds, leads to giddiness and blackouts; loss of blood flow for more than a couple of minutes leads to death of nerve cells and a resulting stroke. Nerve cells cannot regrow so any loss is permanent but recovery is possible by other cells taking over the functions of the dead cells.
Some strokes follow a leakage of blood from one of the arteries in the brain; most result from blockage of arteries with a blood clot. Least common are strokes due to brain tumour or brain injury. The risks of a stroke are increased by anything that increases the risks of diseased blood vessels. This includes, most importantly, high blood pressure, raised cholesterol and smoking. Strokes become much more common with age, due to a general deterioration in the otherwise remarkable reliability of the circulation in the brain. They arc a major cause of disability in old age and a common reason for death in the elderly.
Symptoms of Stroke
The symptoms can range from momentary to permanent. The most obvious symptoms are paralysis of muscles, for example sudden loss of use of an arm or a leg or both, drooping of half the face, slurred speech and difficulty in swallowing. There are more subtle changes in the senses, for example blindness for part of the field of vision, inability to feel part of the body, loss of balance and giddiness.
There is loss in the so-called higher brain functions: an inability to read or articulate correct words, loss of emotional control and confusion – in fact a complete change of personality. The most serious strokes cause sudden unconsciousness then death; others lead to chronic ill health with immobility, incontinence and the increased risk of chest infections.
Treatment of Stroke
After a stroke, the treatment is to provide skilled nursing care while time does its healing. About 25% of stroke victims will localize the site of damage and confirm the type
of stroke: bleeding, obstruction or unexpected disease. It is important to control blood pressure and to stop smoking. Aspirin, in a dose of 75-150 mg a day, reduces the tendency of the blood to clot and so lessens the risks of a future stroke by up to 30%. Investigations may reveal that a blood clot has come from deposits of cholesterol in the carotid arteries; surgery can reopen these vessels (carotid endarterectomy).
Rehabilitation ideally involves a team of physiotherapists, speech and occupational therapists as well as relatives, all pushing the individual to make the best use of her remaining abilities. It can be a long, demanding business because of the changes in personality produced by strokes. Many practical problems need addressing such as learning to transfer in and out of chairs or beds, help with swallowing and with feeding.
Commonly Asked Questions
What is a TIA?
A transient ischaemic attack, or mini-stroke. By definition TIA has all the features of a stroke but complete recovery occurs within 24 hours. They are caused by small blood clots and should lead to as full an investigation as a complete stroke. Aspirin is a very effective treatment for a TIA.
How long can recovery take after a stroke?
Most recovery occurs within three days but still worthwhile improvement happens for at least 12 and possibly 24 mouths. Owing this period the brain ‘reprogrammes’ itself to overcome the damaged area of permanently lost nerve cells.
Is it worth treating blood pressure in the elderly?
Yes, even in the very old. However, doctors do not look for such tight control as they do in younger people.
Complementary treatment of Stroke
Stroke requires prompt hospital treatment. Complementary therapies have a role in prevention and rehabilitation. Nutritional therapy – a high intake of oily fish and vitamin E with a wholefood diet helps prevent small clots in the brain, which cause strokes. Western herbalism – ginkgo promotes cerebral circulation Acupuncture is excellent when used in conjunction physiotherapy, as is chiropractic. Ayurveda – regular treatment helps restore muscular strength. Other therapies to try: shiatsu-do; reflexology; tax chi /chi hung.