Stroke and other neurology
There are three key questions when considering a suspected stroke patient 1) How quickly did this come on? 2) What is the distribution of the problem? 3) Is there any pain?
How quickly did this come on? A stroke comes on very suddenly within half an hour.
What is the distribution of the problem? A stroke tends to affect one side only
Is there any pain? A haemorragic stroke (bleed stroke) is painful (15% of strokes) An ischaemic stroke (clot stroke) is painless (85% of strokes)
Major risk factors for stroke include: Hypertension Smoking Diabetes Alcohol Heart lesions Atrial fibrillation (causes clots to from in the atria which fire off to give stroke)
Young people in Malawi get strokes after they have had rheumatic heart disease. The valves in these patients calcify and parts break off to be fired to the brain to give a stroke.
Is the stroke a Haemorrhage or Infarct?
An infarct stroke is more common than haemorrhage. Infarctive strokes are caused by a clot blocking the blood supply to that area of the brain. These clots can arise from within the brains blood vessels. Blood clots can also break off from the heart valves or carotid arteries and impact in the brains circulation to cause stroke.
A haemorrhagic stroke is caused when a blood vessel breaks inside the brain causing a bleed. The bleeding reduces the blood supply to that area of brain and compresses the area it has bled into.
There is no way clinically to 100% determine whether a stroke is caused by infarct or bleed. A CT scan is needed to reliably determine between haemorrhage and infarction.
However there are clues to a type of stroke…
Provided by T. Whitfield 2012 Haemorrhage commonly causes pain whilst ischaemic stroke doesn’t A haemorrhagic stroke is a more likely to cause loss of consciousness and fitting
On examination of stroke patient The patient should have reduced power and/or sensation on one side of the body compared with the other disturbances in speech and facial asymmetry are common. Some strokes effect the arm, legs and face whilst some just effect one arm or leg.
Typically the patient will present with a flaccid (decreased tone) paralysis on one side which over a few days will become spastic (increased tone). It takes a few days for the upper motor neuron signs to develop.
Investigating stroke patients All stroke patients should have the following tests: Blood sugar: to rule out diabetes Echo: if they are less than 60 years to look for heart valve lesions Blood pressure: see below ECG: routinely done in the west to rule out atrial fibrillation Cholesterol: if the patient can afford the test and treatment
Treating stroke patients
All strokes need the following… Physiotherapy: initiated as early as possible to encourage maximum recovery Swallow assessment: if patient cannot swallow water from a cup without choking they will need NG tube for feeding to prevent aspiration pneumonia. Continence assessment: patient may need catheter if severely incontinent. Regular turning: to prevent pressure sores Blood pressure control: see below Consider Aspirin: if infarctive stroke
Controlling the blood pressure If BP is greater than 220/110 it needs to be reduced to less than 180/90 with hydralazine start with 5mg iv then review an hour later
After 10 days blood pressure target is now 130/80 and BP meds should be adjusted to reach this and reduce the chances of further stroke.
Aspirin Aspirin should be given to those considered to have ischaemic stroke. Acc Malawi treatment guidelines at 75mg od, in other countries 300mg is given for the first 14 days then 75mg for life. Aspirin should be stopped if neurological symptoms worsen whilst taking aspirin as this may mean a bleed has occurred inside the brain. Differential diagnosis of stroke or weakness
Space occupying lesion This often presents with unilateral weakness in the same way as stroke. It tends to come on more slowly and patients often have headache for weeks and months with gradually progressing weakness as the lesion grows and pushes against the brain.
Space occupying lesions are common in HIV positive individuals common causes are: toxoplasma, cryptococcoma, tuberculoma and lymphoma. Refer to HIV guidelines. Tumours can also arise in non HIV positive individuals a CT/MRI scan is ideal to diagnose.
Todds palsy This is neurological symptoms post seizure. Any neurological assessment has to be reserved for 24 hours after seizure as post seizure can mimic stroke.
Hypoglyaemia can also mimic stroke, it is treated as per protocal.
Paraplegia This is weakness of both the lower limbs, sudden onset bilateral lower limb weakness is usually caused by spinal cord compression in Malawi. They present with sudden onset leg weakness with incontinence and lack of genital sensation.
On examination these patients tend to have either increased tone and decreased sensation in the lower limbs or decreased tone with decreased sensation. This is because as with stroke it takes time for the increased tone to develop in upper motor neuron lesions (see neurological examination).
Common causes of spinal cord compression are… TB spine Schistosomiasis Trauma Tumour metastasis Syphilis Treatment of paraplegia
Involves treating the underlying cause (TB treatment, praziquantel for schistosomiasis). Steroids are of benefit to reduce swelling and compression especially if TB spine is suspected.
General measures include Regular rotation to prevent pressure sores (2 hourly) Catheter if incontinent Adequate nutrition Provided by T. Whitfield 2012