Hemiplegia

 

INSTRUCTION

Carry out a neurological examination of this patient.

SALIENT FEATURES

History

· Obtain history of headache, seizures and loss of consciousness (more common in subarachnoid haemorrhage or intracerebral

bleeds than in cerebral infarction).

· History of speech defects, sensory loss and weakness of face and limbs.

· Risk factors: hypertension, smoking, diabetes mellitus.

· History of functional status: swallowing, mobility, pressure sores, independence in activities of daily living, visual difficulties (for

visual field defects).

Examination

· Unilateral upper motor neuron seventh nerve palsy.

· The arm is held to the side, the elbow is flexed, and the fingers and wrist are flexed on to the chest.

· The leg is extended at both the hip and knee, while the foot is plantar flexed and inverted.

· Weakness of the upper and lower limbs on the same side with upper motor neuron signs - increased tone, hyper-reflexia and

upgoing plantar response.

- Hemiplegic weakness of the upper limbs affects the shoulder abductor, elbow extensors, wrist and finger extensors, and small

hand muscles.

-Hemiplegic weakness of the lower limbs affects hip flexors, knee flexors and

dorsiflexors and evertors of the foot.

· Do not forget sensory signs, in particular joint sensation which is important in rehabilitation.

Proceed as follows:

· Examine:

-For homonymous hemianopia and sensory inattention. -For carotid bruits. -For speech defects.

-The pulse for atrial fibrillation.

-The heart for murmurs.

· Tell the examiner that you would like to check the blood pressure and check the urine for sugar.

DIAGNOSIS

This patient has had a stroke causing a right or left hemiplegia (lesion) which can be caused either by a vascular event such as

thrombosis, embolism or haemorrhage,

or by a neoplasm of the brain (aetiology). This patient is limited by hemiplegia and hemianopia (functional status).

QUESTIONS

What are the causes of hemiplegia?

About 80% of all strokes are due to cerebral infarction resulting from thrombotic or embolic occlusion of a cerebral artery (J Neural

Neurosurg Psych 1990; 53: 16-22). The remaining 20% are caused by either intracerebral or subarachnoid haemorrhage.

Elderly:

· Vascular event (thrombosis, embolism or haemorrhage).

· Tumour.

· Subdural haematoma.

· Syphilis.

Youth:

· Multiple sclerosis. · Tumour. · Trauma.

· Embolism (look for underlying valvular heart disease, atrial fibrillation). · Connective tissue disorder. · Neurosyphilis.

· lntracranial infection: look for underlying acquired immune deficiency syndrome

(AIDS), otitis media, cyanotic heart disease.

How would you manage such a patient?

· Early hospital admission, preferably to a dedicated stroke unit, which has been shown to produce long-term reductions in death,

dependency and need for institutional care (BMJ 1997; 314:1151-9).

· Aspirin given within 48 hours of ischaemic stroke reduces the risk of death and recurrent stroke. The international stroke trial

(Lancet 1997; 349:1569-81) and the Chinese stroke trial (Lancet 1997; 349: 1641-9), each concerning 20000 patients, found

that aspirin was associated with about 10 fewer deaths or recurrent strokes, but with slightly more haemorrhagic strokes. The

international stroke trial reported no benefit from subcutaneous heparin given with or without aspirin.

· FBC, ESR.

· Urine sugar.

· ECG.

· Chest radiography.

· Echocardiography (looking for source of emboli), computed tomography (CT), carotid digital subtraction angiography (DSA) in

selected patients.

· Physiotherapy, speech therapy and occupational therapy.

· Control of risk factors - stop smoking, hypertension, hyperlipidaemia, diabetes, stop oral contraceptives.

Discuss the importance of blood pressure reduction in a patient with acute ischaemic stroke

Randomized clinical trials suggest that acute ischaemic stroke patients treated with

antihypertensive agents may have an adverse clinical outcome and increased mor-tality (BMJ 1988; 296: 73741; Cerebrovasc Dis

1994; 4: 204-10).

ADVANCED-LEVEL QUESTIONS

What are the measures used to determine the outcome after an acute stroke ?

Some of the standard measures include:

* Barthel index is a reliable and valid measure of the ability to perform activities of daily living such as eating, bathing, walking and

using the toilet.

· Modified Rankin Scale is a simplified overall assessment of function in which a score of 0 indicates the absence of symptoms

and a score of 5 shows severe disability.

· Glasgow Outcome Scale is a global assessment of function in which a score of 1 indicates good recovery, a score of 2

moderate disability, a score of 3 severe disability, a score of 4 survival but in a vegetative state, and a score of 5 death.

· NIH Stroke Scale, a serial measure of neurological deficit, is a 42-point scale that quantifies neurological deficits in 11

categories. For example, a mild facial paralysis is given a score of 1 and complete right hemiplegia with aphasia, gaze

deviation, visual field deficit, dysarthria and sensory loss is given a score of 25. Normal function without neurological deficit is

scored as zero.

What is the role of thrombolysis in acute stroke?

Treatment with intravenous tissue plasminogen activator (tPA) when administered within 3 hours after onset of the ischaemic event

(and in the absence of any sign of brain injury on CT) improves clinical outcome at 3 months (N Engl J Med 1995; 333: 1581-7). The

CT scan in these patients must be examined very carefully for evidence of hemispheric brain ischaemia, which may increase the risk

of deterio-ration, with or without cerebral haemorrhage, after thrombolytic treatment. An over-view of previous trials found significant

excesses of early and total deaths, and of symptomatic and fatal intracranial haemorrhages, after acute thrombolysis, but a

significant reduction in death or dependency in patients randomized to treatment within 3 hours of stroke onset (Lancet 1997; 350:

607-14). It remains unclear which patients are most likely to benefit or be harmed.

What is the role of anticoagulants in the immediate treatment of acute ischaemic stroke?

Anticoagulants (including unfractionated heparin, low molecular weight heparin or specific thrombin inhibitors) offer no short- or

long-term benefits in the immediate treatment of acute ischaemic stroke. Although the risks of deep venous thrombosis or pulmonary

embolus are significantly reduced, these benefits are offset by a dose-dependent increased risk of intracranial or extracranial

bleeding.

What is the prognosis in a patient with acute ischaemic stroke?

About 10% of' these patients will die within a month from the onset of the stroke (J Neurol Neurosurg Psych 1990; 53: 824-9). Of

those who survive the acute event, about half will experience some disability after 6 months (J Neurol Neurosurg Psych 1987; 50:

177-82).

What is the significance of carotid artery stenosis?

· Carotid artery stenosis is an important predisposing factor for cerebrovascular ischaemic events, the risk increasing with the

severity of the stenosis and the presence of symptoms.

· For severe (>70% narrowing) symptomatic stenosis, carotid endarterectomy is recommended.

· For severe symptom-free stenosis, optimal management has yet to be defined: one meta-analysis of trials showed only a small

absolute benefit from surgery in reducing the odds of ipsilateral stroke (BMJ 1998; 317: 1477-80). Also, 45% of strokes in

patients with asymptomatic stenosis with 60-99% nan-rowing are attributable to lacunae or cardioembolism (N Eng/J Med

2000; 342: 1693-700). Carotid endarterectomy can not, therefore, be routinely recommended.

· For mild to moderate symptomatic stenosis (<70% narrowing), antiplatelet agents such as aspirin are recommended. Persistent

symptoms may necessitate use of other agents such as ticlopidine, or clopidogrel, which reduces the relative risk for further

ischaemic events slightly more than aspirin (CAPRIE trial, Lancet 1996; 348:1329 39).

How would you manage a patient with a transient ischaemic attack

(TIA)?

· Give advice on stopping smoking.

· Aspirin.

· Duplex ultrasonography of the carotid vessels.

· Carotid artery DSA.

What do you understand by the term 'TIA'?

An acute loss of focal cerebral or ocular function with symptoms lasting less than 24 hours.

Why is it important to differentiate a carotid TIA from a vertebrobasilar TIA ?

Carotid TIAs may be amenable to surgery. Furthermore, a TIA in the anterior circulation is generally of more serious prognostic

significance than a TIA in the posterior circulation.

What are the features of a carotid TIA?

Hemiparesis, aphasia or transient loss of vision in one eye only (amaurosis fugax).

What are the features of a vertebrobasilar TIA?

· Vertigo, dysphagia, ataxia and drop attacks (at least two of these should occur together).

· Bilateral or alternating weakness or sensory symptoms.

· Sudden bilateral blindness in patients aged over 40 years.

What are the clinical features that would interest you for the rehabilitation of a stroke patient?

· Independence in activities of daily living - bathing, dressing, toileting, trans-ferring, continence and feeding.

· Independence in more complex activities such as meal preparation, shopping, financial management, housekeeping,

transportation, medication-taking and laundering.

What are the risk factors for stroke?

Hypertension, ischaemic heart disease, atrial fibrillation, peripheral vascular disease. diabetes, smoking, previous TIA, cervical bruit,

hyperlipidaemia, raised haematocrit, oral contraceptive pill, cardiomyopathy.

Why is it important to treat TIAs?

Prospective studies have shown that within 5 years of a TIA:

· One out of six patients will have suffered a stroke.

· One out of four patients will have died (due either to stroke or heart disease).

What is the role of carotid endarterectomy in patients with a carotid TIA ?

· For patients with severe stenosis (70-99%) the risks of surgery are significantly outweighed by the later benefits.

· For patients with mild stenosis (0-50% of cases) there is little 3-year risk of ipsilateral ischaemic stroke, even in the absence of

surgery, so that any 3-year benefits of surgery are small and outweighed by its early risks (N Engl J Med 2000; 342: 1743-5).

· For patients with moderate stenosis (50-69% of cases) the balance of surgical risk and eventual benefit is still being evaluated.

What is the role of carotid angioplasties in patients with recent carotid artery TIAs who have severe stenosis of the

ipsilateral carotid artery?

This procedure has not been adequately assessed in patients with recent carotid artery TIAs or those with non-disabling ischaemic

stroke who have severe stenosis of the ipsilateral carotid artery, and hence is not recommended. However, registry data suggest

that carotid artery stenting may be useful in carefully selected patients. The CREST trial - a randomized trial funded by the NIH to

examine the role of carotid stenting - is currently ongoing.

What do you understand by the term 'RIND'?

Reversible ischaemic neurological disease, in which symptoms and signs reverse within 1 week but not within 24 hours.

What are lacunar infarcts?

Lacunar infarcts are seen in hypertensive patients and consist of small infarcts in the region of the internal capsule (causing partial

hemiparesis or hemisensory impairment), pons (ataxia of cerebellar type, partial hemiparesis), basal ganglia or thalamus. They are

often multiple. Lacunae are thought to be caused by occlusion of small branch arteries or by rupture of Charcot-Bouchard

microaneurysms producing a small haematoma which resolves, leaving an area of infarction.

What areas of the brain are supplied by the anterior carotid artery?

The anterior carotid artery supplies the frontal lobes and the medial cerebral hemispheres with the exception of the visual cortex of

the occipital lobes. Cortical areas supplied by this artery include the motor and sensory areas of the lower limbs, a 'micturition centre'

and the supplementary motor cortex. Ischaemia in the territory of one anterior carotid artery produces weakness and mild sensory

deficits in the opposite lower limb. Some patients with left anterior carotid artery ischaemia have a mild transient aphasia.

What do you understand by the term 'stroke'?

Stroke is characterized by rapidly progressive clinical symptoms and signs of focal, and at times global, loss of cerebral function

lasting more than 24 hours or leading to death, with no apparent cause other than that of vascular origin (Bull World Health Organ

1976; 54: 541-53).

How do you classify stroke?

Using the Bamford clinical classification of stroke:

Total anterior circulation syndrome

·