Stroke develops due to focal ischemia (reduced blood supply) or hemorrhage in the brain resulting in focal deficit of brain function (that should last more than 24 hours) . It is the most common cause of physical disability and third most common cause of death in the developed world (after cancer and heart disease) . Two thirds of stroke patients are aged over 60 years. Unfortunately, about one fifth of patients with stroke will die within a month of attack and half of those who survive will be left with physical disability in the long run.
Transient ischemic attack - Stroke in which symptoms disappear after 24 hours.
Progressive stroke - Where neurological deficit worsens gradually.
Completed stroke - Where deficit persist but doesn't progress.
Why it occurs
In about 85% cases stroke occurs as result of inadequate blood flow to part of the brain. The remaining 15% patients will have had a hemorrhage in the brain.
Some important predisposing factors
Age >65 years
Sex (male > female)
Race (Afro- Caribbean > Asian > European)
Previous history of heart attack, embolism
High blood pressure
High cholesterol level
Excessive alcohol consumption
How patients present with stroke
Patient may present with unilateral motor weakness, difficulty in speech, double vision, vertigo, visual field defect etc. When patients come with reduced conscious level, it usually indicates large brain lesion. Individual clinical presentation depends on the area of brain involved.
How is it diagnosed
Brain imaging (CT or MRI) is the investigation of choice in patient with stroke. CT scan is the most widely available imaging modality for acute stroke. In can demonstrate bleeding into the brain within minutes of onset.
What to look for in a patient with acute stroke
Breathing - Monitor the breathing pattern of the patient (whether it is regular or irregular)
Circulation and blood pressure (usually blood pressure is allowed to remain slightly high)
Hydration and nutrition (give parenteral nutrition or start feeding by nasogastric tube if swallow is unsafe)
Blood glucose level (keep blood sugar level below 200mg/dl)
Temperature (treat infection and give antipyretic early)
Pressure areas (use a pressure relieving mattress and turn immobile patient every two hourly)
Incontinence (ensure the patient is not constipated or in urinary retention)
Reducing the risk of future strokes
Stroke patients are prone to develop further strokes (5-10% within one week, 15% in the first year) . Patients are given some specific medications to reduce recurrence of stroke (like anti platelet, anti hypertensive, lipid lowering and blood glucose controlling drugs).
Other important lifestyle modifications are:
Lowering salt intake
Lowering fat intake
Limiting alcohol intake
Increasing aerobic exercise
Losing excessive weight.