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					DIAGNOSIS AND INITIAL MANAGEMENT OF ACUTE STROKE AND
           TRANSIENT ISCHAEMIC ATTACK (TIA)



CONTENTS                                                                          PAGE



DEFINITIONS                                                                         1

RAPID RECOGNITION OF SYMPTOMS AND DIAGNOSIS                                         2

EMERGENCY MANAGEMENT OF TIA                                                         3-5

EMERGENCY MANAGEMENT OF ACUTE STROKE                                                6

       THROMBOLYSIS                                                                 7

       MEDICAL TREATMENT OF ACUTE ISCHAEMIC STROKE                                  8-10

       SURGERY FOR ACUTE STROKE                                                     11

SECONDARY PREVENTION OF STROKE AND TIA                                              12-14

DISCHARGE AND FOLLOW UP                                                             15




DEFINITIONS
STROKE is defined as a clinical syndrome consisting of rapidly developing clinical signs of focal (at
times global) disturbance of cerebral function, lasting more than 24 h or leading to death with no
apparent cause other than that of vascular origin.

TIA is defined as stroke symptoms and signs that resolve within 24 hours. Most TIAs resolve in
minutes or a few hours at most and anyone with persistent symptoms should be assumed to be
having a stroke.


                                                  1
RAPID RECOGNITION OF SYMPTOMS AND DIAGNOSIS
In patients with sudden onset of neurological symptoms:

      a validated tool, such as FAST (Face Arm Speech Test), should be used outside hospital to
       screen for a diagnosis of stroke or TIA.
      hypoglycaemia should be excluded as the cause of these symptoms.

Patients who are admitted to the emergency department with a suspected stroke or TIA should
have the diagnosis established rapidly using a validated tool, such as ROSIER (Recognition of
Stroke in the Emergency Room).




                        Score NEW symptoms only          YES      Score      NO      Score

                       Unilateral facial weakness?                 1                 0
                        Unilateral arm weakness?                   1                 0
                          Unilateral leg weakness?                 1                 0
                              Speech disturbance?                  1                 0
                                Visual field defect?               1                 0

                Loss of consciousness or syncope?                  -1                0
                                      Any seizures?                -1                0

                                    ROSIER SCORE:                  ___




ROSIER scores of >0 strongly suggest acute stroke / TIA as a diagnosis; thrombolysis, direct
admission to the stroke unit on 411 and other neuroradiological interventions may be urgently
required.



ROSIER scores of -2 to 0 are less likely to be acute stroke / TIA; unless clinical suspicion of stroke
high, consider other diagnoses and/or referral to RMO

It is rare for a stroke to cause a significantly decreased conscious level (GCS <9) in the absence of
any focal neurology. Acute confusion in the absence of more focal symptoms or a true dysphasia
is also likely to have a different aetiology.




                                                   2
EMERGENCY MANAGEMENT OF TIA
Patients who have had a suspected TIA (that is, they have no neurological symptoms at the time
of assessment should be assessed as soon as possible for their risk of subsequent stroke using a
validated scoring system, such as ABCD2.



                         ABCD2 SCORE                                            SCORE
                  A      Age >60 years                                             1
                  B      BP >140 mmHg systolic or >90 mmHg diastolic               1
                  C      Unilateral weakness (motor)                               2
                         Speech disturbance without any weakness                   1
                         Other                                                     0
                  D      Duration > 60 minutes                                     2
                         10-59 minutes                                             1
                         < 10 minutes                                              0
                  D      Diabetes                                                  1


High Risk TIAs (ABCD2 ≥ 4)

Patients who have had a suspected TIA who are at high risk of stroke (that is, with an ABCD 2 score
of 4 or above) should have:

      Aspirin (300 mg daily) started immediately
      Specialist assessments and investigation within 24 hours of onset of symptoms
      Advise the patient not to drive until seen by a specialist
      Fax the TIA referral form to the rapid access TIA clinic via an internal fax on 0121 460 5832
      If clinical concerns remain then admission via the CDU can be arranged and assessments
       and investigations should proceed as an in-patient.
      Advice is available via the Stroke Co-ordinator (07769 932 342) or from the on-call stroke
       consultant via switch.

If the patient has to be admitted to CDU / Acute Stroke Unit due to clinical concerns and in order
to facilitate rapid treatment then these should all occur as an in-patient. The risk of early stroke in
high risk patients is substantial.

NB: Patients with crescendo TIA (i.e. two or more TIAs in a week) should be treated as being at high
risk of stroke, even though they may have an ABCD2 score of 3 or below.




                                                   3
Examples of situations that may also be considered high risk and warrant attention within 24
hours and / or admission include but is not restricted to:

      Persistent symptoms
      Fluctuating symptoms
      Failed swallow
      Paroxysmal atrial fibrillation
      BP > 180/100
      Abnormal CT / bloods / ECG
      Recurrent TIAs ( >2 events in a week)
      TIA / Stroke and AF
      TIA / Stroke and on warfarin
      Young patients with TIA and neck pain( <50 years)
      TIA / Stroke and prosthetic valve



Low Risk TIAs (ABCD2 ≤ 3)

People who have had a suspected TIA who are at lower risk of stroke (that is, an ABCD 2 score of 3
or below) should have:

      Aspirin (300 mg daily) started immediately
      Specialist assessment and investigation within 1 week of onset of symptom
      Advise the patient not to drive
      Fax the TIA referral form to the rapid access TIA clinic via an internal fax on 0121 460 5832
      Advice is available via the Stroke Co-ordinator (07769 932 342) or from the on-call stroke
       consultant via switch.

People who have had a TIA but who present late (more than 1 week after their last symptom has
resolved) should be treated as though they are at lower risk of stroke even if their ABCD 2 score is 4
or above.

Unless cerebral haemorrhage is strongly suspected (severe headache / severe hypertension) then
commence antiplatelets in high and low risk patients immediately.

If there is any doubt about the safety of antiplatelets and / or the safety of discharge to a
outpatient rapid access service then is advice as always is available via the Stroke Co-ordinator
(07769 932 342) or from the on-call stroke consultant via switch.




                                                   4
Brain imaging in TIA

People who have had a suspected TIA (that is, whose symptoms and signs have completely
resolved within 24 hours) should be assessed by a specialist before a decision on brain imaging is
made.

People who have had a suspected TIA in whom the vascular territory or pathology is uncertain
should undergo urgent brain imaging (preferably a diffusion-weighted MRI).

CT scanning in TIA patients should be reserved for those in whom MRI is contraindicated.

Examples where brain imaging is helpful in TIA include patients being considered for carotid
endarterectomy in whom it is uncertain if the event was in the anterior or posterior circulation;
patients in which there is clinical doubt about the diagnosis (such as epilepsy, migraine or tumour);
or situations where haemorrhage needs excluding such as with persistence of symptoms or the
presence of anticoagulants.



Carotid imaging in TIA patients

All patients with a carotid territory TIA who are candidates for carotid endarterectomy after
specialist assessment should have a carotid imaging within 1 week of onset of symptoms (if
presenting within 1 week).

This should ideally always be requested via the vascular technicians (in outpatients or in CDU) on
extension: and not through general radiology.

Patients with a symptomatic carotid stenosis of 70% - 99% by ECST criteria (50%-99% by NASCET
criteria) should be referred for carotid endarterectomy within 2 weeks from onset of symptoms
and receive best medical therapy (see below) in the meantime.

The evidence for surgery in asymptomatic carotid disease and stenosis below 70% (ECST) remains
limited though can be discussed on a case by case basis. Best medical therapy is usually the
recommended action in most instances.




                                                  5
EMERGENCY MANAGEMENT OF ACUTE STROKE
Specialist stroke units

All people with suspected stroke should be admitted directly to a specialist acute stroke unit
following initial assessment, either from the community or from the A&E department.

This may necessitate that a medical clerking occurs in the ED or on the acute stroke ward itself.
Patients should not wait in the ED for clerking and timely admission to the stroke unit should be
the priority after confirmation of the diagnosis and completion of necessary imaging.

Confirmed stroke patients should ideally be on the acute stroke unit within 4 hours of admission.
Access the acute stroke unit by calling the Stroke Co-ordinator (07769 932 342) or ringing the
nurse in charge of the acute stroke unit.



Brain imaging for the early assessment of people with acute stroke

Brain imaging should be performed immediately for people with acute stroke if any of the
following apply:


                   Indication for thrombolysis or early anticoagulation treatment
                   On anticoagulant treatment
                   A known bleeding tendency
                   A depressed level of consciousness (Glasgow Coma Score below 13)
                   Unexplained progressive or fluctuating symptoms
                   Papilloedema, neck stiffness or fever
                   Severe headache at onset of stroke symptoms


For all other patients with acute stroke without an indication for immediate brain imaging,
scanning should still be performed as soon as possible and certainly within 24 hours of onset of
symptoms.

CT angiography / CT perfusion scanning may be useful to determine whether intra arterial lysis or
mechanical lysis would be warranted and should remain at the discretion of the specialist stroke
team and neuroradiology.

MRI with DWI should be considered particularly in patients being considered for carotid
endarterectomy in whom it is uncertain if the event was in the anterior or posterior circulation;
patients in which there is clinical doubt about the diagnosis (such as epilepsy, migraine or tumour);
or in patients who present > 2 weeks after stroke where CT is then less effective in determining
the type of stroke.

                                                 6
THROMBOLYSIS
IV thrombolysis with alteplase

Intravenous alteplase is currently recommended for the acute treatment of ischaemic stroke up to
4.5 hours after symptom onset. It should be delivered only by physicians trained and experienced
in the management of acute stroke. Contact the on-call Specialist Registrar for Stroke or the
Stroke Consultant via switchboard immediately.

Thrombolysis protocols including exclusion criteria and dosing charts are available in the
Emergency Department and on the intranet (link)

If a potential thrombolysis case is admitted delays should be minimised with the aim to achieve a
door-to-needle time below 60 minutes.


   Immediately call the Stroke Co-ordinator (07769 932 342)
   After 8pm contact the Specialist Registrar on-call for Stroke or the Stroke Consultant directly
   via switchboard
   Contact the on-call Radiology Specialist Registrar to request an immediate CT head scan
   Obtain as much collateral history as is available and insert a peripheral cannula in each arm


Please be aware that the indications for thrombolysis and newer interventional therapies are
frequently revised. If in any doubt as to whether thrombolysis or any other intervention is
needed please speak to the stroke team for clarification.



IA thrombolysis and mechanical clot retrieval

In some situations for example where peripheral intravenous lysis is contraindicated; > 4.5 hours
has elapsed since onset of symptoms; or if there is a failure of conventional treatment; intra-
arterial lysis may be indicated +/- mechanical clot retrieval.

This is always done via the on-call stroke consultant in discussion with the interventional
neuroradiology department on a case by case basis and may involve CTA or perfusion studies.



Research and newer treatments

Research trials are underway to assess lysis up to 6 hours (9 hours in some areas) and mechanical
clot retrieval has sometimes been performed up to 8 hours and beyond so please consider each
case on its own merits and call the stroke team for advice if in doubt.



                                                 7
MEDICAL TREATMENT OF ACUTE ISCHAEMIC STROKE
Aspirin and anticoagulants

All people presenting with acute stroke who have had a diagnosis of primary intracerebral
haemorrhage excluded by brain imaging should, as soon as possible and certainly within 24 hours,
be given:

      Aspirin 300 mg orally if they are not dysphagic or
      Aspirin 300 mg rectally or by enteral tube if they are dysphagic

Aspirin should be continued for 2 weeks or until discharge when long-term treatment can be
commenced. (See Secondary prevention of Stroke and TIA)

Any patient genuinely intolerant of aspirin should be prescribed an alternative antiplatelet such as
clopidogrel 75mg once daily.

Patients with cerebral sinus thrombosis (even in the presence of secondary intracerebral
haemorrhage) should be fully anticoagulated with treatment dose enoxaparin followed by
warfarin to maintain an INR of between 2.0 and 3.0.

Patients with stroke secondary to acute arterial dissection should be treated with either
antiplatelets or anticoagulants or recruited into a randomised controlled trial when available.



Anticoagulation treatment for other conditions

Patients with disabling ischaemic stroke who are in atrial fibrillation should be treated with
aspirin 300 mg for the first 2 weeks before considering formal anticoagulation.

Patients with prosthetic valves who have disabling cerebral infarction and who are at significant
risk of haemorrhagic transformation, should have their anticoagulation treatment should be
stopped for 1 week and aspirin 300 mg substituted.

Patients with ischaemic stroke and a symptomatic proximal deep venous thrombosis or a
pulmonary embolus should receive anticoagulation instead of aspirin. Patients with a
haemorrhagic stroke may require anticoagulation treatment +/- a caval filter.



Statin therapy

There is no evidence of benefit for immediate initiation of statins in stroke. Statins for secondary
prevention can usually be safely commenced after 48 hours. (See Secondary prevention of Stroke
and TIA)

Patients already taking statin therapy do not need to have their treatment paused.

                                                 8
Oxygen therapy

Supplemental oxygen should be used only if saturations drop below 95%. Routine use of oxygen
in acute stroke is not recommended if patient is not hypoxic.



Blood sugar control

Patients with acute stroke should have the blood sugar maintained between 4mmol/L and
11mmol/L where possible. This may require the use of intravenous insulin in selected cases but
with caution as hypoglycaemia is potentially hazardous.



Blood pressure control

Anti-hypertensive treatment in people with acute stroke is recommended only if there is a
hypertensive emergency with one or more of the following serious concomitant medical issues:


            Intracerebral haemorrhage with systolic blood pressure over 200 mmHg
                 Post-thrombolysis with a blood pressure over 185/105 mmHg
                                   Hypertensive encephalopathy
                                    Hypertensive nephropathy
                         Hypertensive cardiac failure/myocardial infarction
                                         Aortic dissection
                                     Pre-eclampsia/eclampsia


Blood pressure reduction to below 185/105 mmHg can be considered in hypertensive patients to
allow thrombolysis but only with the involvement of the stroke team and then with caution.



Treatment options (parenteral)

      Labetalol 10 mg IV over 1-2 minutes
      GTN infusion 20mg in 50mls to run at between 2-10ml/hr
      Labetalol infusion at 2 - 8 mg/min




                                                 9
Nutrition and hydration

Many people with acute stroke are unable to swallow safely, and may require supplemental
hydration and nutrition.

Assessment of swallowing function

On admission, people with acute stroke should have their swallowing screened by an
appropriately trained healthcare professional before being given any oral food, fluid or medication
within 4 hours of admission. (link to: Dysphagia Screening Guidelines)

If the admission screen indicates problems with swallowing, the person should have a specialist
assessment of swallowing, preferably within 24 hours of admission and not more than 72 hours
afterwards.

Patients with acute stroke expected to survive who are unable to take adequate nutrition and
fluids orally should:

      receive tube feeding with a nasogastric tube within 24 hours of admission
      be considered for a gastrostomy if they are unable to tolerate a nasogastric tube or if there
       is no improvement in swallowing after 3 weeks
      be referred to an appropriately trained healthcare professional for detailed nutritional
       assessment, individualised advice and monitoring

Patients with acute stroke should be screened for malnutrition on admission and weekly
thereafter using a validated tool such as the Malnutrition Universal Screening Tool (MUST).

Patients at risk of malnutrition may require oral supplementation, dietary advice and/or
nasogastric feeding.

Well nourished patients do not need routine oral supplements.

Patients should have their hydration assessed on admission and regularly thereafter so that
normal hydration is maintained.




                                                10
SURGERY FOR ACUTE STROKE
Surgical referral for acute intracerebral haemorrhage

Patients with intracranial haemorrhage should be monitored by specialists in neurosurgical or
stroke care for deterioration in function and referred immediately for brain imaging when
necessary.

Previously fit people should be considered for surgical intervention following primary intracranial
haemorrhage if they have hydrocephalus. This is particular likely in patients with cerebellar
haemorrhages (and also infarctions) which can cause 4th ventricle compression.

Patients with any of the following rarely require surgical intervention and should receive medical
treatment initially:

      small deep haemorrhages
      lobar haemorrhage without either hydrocephalus or rapid neurological deterioration
      a large haemorrhage and significant co-morbidities before the stroke
      a score on the Glasgow Coma Scale of below 8 unless this is because of hydrocephalus
      posterior fossa haemorrhage



Surgical referral for acute ischaemic stroke

Decompressive hemicraniectomy

Patients with middle cerebral artery infarction who meet all of the criteria below should be
considered for decompressive hemicraniectomy. They should be referred within 24 hours of onset
of symptoms and treated within a maximum of 48 hours.

      Aged 60 years or under.
      Clinical deficits suggestive of infarction in the territory of the middle cerebral artery, with a
       score on the National Institutes of Health Stroke Scale (NIHSS) of above 15.
      Decrease in the level of consciousness to give a score of 1 or more on item 1a of the NIHSS.
      Signs on CT of an infarct of at least 50% of the middle cerebral artery territory, with or
       without additional infarction in the territory of the anterior or posterior cerebral artery on
       the same side, or infarct volume greater than 145cm3 as shown on diffusion-weighted MRI.

Posterior fossa decompression

Patients with cerebellar infarction and effacement of the 4 th ventricle as with cerebellar
haemorrhage are at risk of hydrocephalus and should be discussed with the neurosurgical team
for consideration of decompression.




                                                  11
SECONDARY PREVENTION OF STROKE AND TIA
There is little or no distinction made between the secondary prevention of acute ischaemic stroke
and transient ischaemic attacks (TIA). This section details the interventions taken to prevent
recurrent strokes and TIAs following the initial treatment of the acute phase as detailed above.

Antiplatelet therapy

Patients with an acute ischaemic stroke should be commenced on lifelong antiplatelets therapy for
the long term prevention of further strokes. Clopidogrel is likely at least as efficacious as
aspirin/dipyridamole combination therapy.

The following combination is recommended in order of cost effectiveness (NICE: December 2011)


            1. Clopidogrel 75 mg daily
            2. Aspirin 75 mg daily + Dipyridamole MR 200mg twice daily
            3. Aspirin 75mg daily
            4. Dipyridamole MR 200mg twice daily



Clopidogrel currently lacks a specific license for use in TIA though there is no compelling reason
why it should not be effective and it is widely used, especially in aspirin intolerant patients.

Aspirin in combination with clopidogrel is not recommended in patients with acute ischaemic
stroke as their sole pathology but has a potential indication in those with cardiac disease.



Anticoagulants

Anticoagulation with warfarin (or newer oral anticoagulants such as dabigatran) should be
considered in all patients with acute ischaemic stroke and atrial fibrillation (paroxysmal or
chronic). Warfarin reduces the relative risk of recurrent stroke by as much as two thirds.

Anticoagulation is usually started two weeks after acute ischaemic stroke and continued for life
unless there are compelling contraindications. A solitary fall would not normally be considered a
compelling contraindication.

Patients with an acute stroke from another embolic focus other than atrial fibrillation may also
require anticoagulation.




                                                 12
Antihypertensives

Blood pressure should be maintained below 140/85 mmHg (and below 130/80 mmHg in diabetic
patients) to reduce the risk of recurrent stroke. Blood pressure reduction is probably more
important than using any specific agent though thiazide diuretics and ACE inhibitors are usually
considered first line.

Calcium channel blockers are also effective especially in older patients and also reduce blood
pressure variability which looks increasingly important in reducing the risk of stroke

Beta-blockers are generally not recommended unless there is another compelling indication (such
as rate control of AF)



Statin therapy

Statin therapy should be considered for all acute ischaemic stroke patients with a total random
cholesterol above 3.5 mmol/L. Treatment is not usually newly started for at least 48 hours post
stroke. Simvastatin 40mg daily or equivalent dose of an effective statin (such as atorvastatin
20mg daily) is recommended. There is currently no direct evidence to support the use of fibrates
or ezetimibe in stroke patients.

The benefit of lowering cholesterol in acute haemorrhagic stroke remains unclear and is not
currently recommended.



Other investigations and treatments

Carotid artery disease

In stroke patients with carotid territory strokes who have made a good or complete recovery and
are candidates for carotid endarterectomy should have carotid imaging.

This should ideally always be requested via the vascular technicians (in outpatients or in CDU) on
extension: and not through general radiology.

Patients with a symptomatic carotid stenosis of 70% - 99% by ECST criteria (50%-99% by NASCET
criteria) should be referred for carotid endarterectomy within 2 weeks from onset of symptoms
and receive best medical therapy in the meantime.




                                                13
Echocardiography (+/- contrast)

Transthoracic echocardiography should be considered in patients with acute ischaemic stroke if a
cardio embolic focus is suspected. This may include patients with the following:

      Abnormal ECG
      Abnormal heart sounds / murmurs on auscultation
      Clinically or radiological evidence of an enlarged heart
      Multiple cerebral infarctions of similar age

In patients with no clear cause or risk factors for acute ischaemic stroke and who are under the
age of 50 years should be considered for a contrast echocardiogram following discussion with the
stroke team and/or the cardiologists.

The presence of a patent foramen ovale (PFO) on contrast echocardiography in these patients may
require device closure in addition to normal best medical treatment especially in the presence of
recurrent stroke or TIA despite best medical therapy.



Young stroke

Young patients (under 50 years old) especially those with few or limited risk factors for stroke may
require further additional investigations to determine the underlying aetiology. These should be
undertaken in conjunction with the stroke team.

Examples of additional investigations that may be required include but are not restricted to:

      Vascular brain imaging modalities (CTA / MRA head and or neck)
      Cerebral angiography
      Thrombophilia screen (+/- sickle screen if appropriate ethnicity)
      Vasculitic and antiphospholipid screen
      Genetic investigations (e.g. MELAS, CADASIL, Fabry’s disease)




                                                 14
DISCHARGE AND FOLLOW UP
Stroke patients discharged from the acute hospital usually require ongoing support and follow up
from a number of specialties and support agencies.

Patients may be discharged home directly, with or without the support of a stroke specific
rehabilitation community team or via Moseley Hall Hospital (Ward 8) following a further period of
in-patient rehabilitation if this is required.



Stroke clinic follow-up

Out-patient follow up may consist of a number of ongoing therapy appointments but will usually
at least include a 6 week appointment with a stroke consultant on the acute site and a 12 week
appointment in the community stroke clinic.

Please access through the Stroke Co-ordinator (07769 932 342) or alternatively fax the PICS
discharge letter to the rapid access TIA clinic on 0121 460 5832 marking it for ‘stroke follow-up’.

Depending on their requirements patients may also be followed up by vascular surgery,
neurosurgery and / or neuro-opthalmology.

The latter is relevant in those patients with persistent field defects and / or diplopia especially if
they are drivers.

All stroke patients should also receive a Stroke Association pack with contact details for a local
support worker who also has access to contacts in housing, social services and in the voluntary
sector.




                                                   15

				
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