1 - Assessment and Management of Acute Stroke COPY Flashcards
What is the acute stroke pathway from a patient calling 999 to treatment?
- Priority 1 Ambulance sent and they review
- If they think stroke they call RAP phone
- Front door take focused history, exam (inc NIHSS) and investigations (bloods, IV access, ECG)
- Wheel straight to CT
- Decide treatment immediately based on CT and history
- Hyperacute stroke unit
What happens after a patient has recieved their initial stroke treatment/assessments and they are on the hyperacute stroke unit?
- Stay on ward for 24-48 hours or until medically stable then:
What are the initial questions you need to ask when managing an acute stroke?
Does the patient have vascular factors? (e.g HTN)
What is the definition of a stroke?
A clinical syndrome of rapidly developing clinical signs of focal disturbance of cerebral function lasting greater than 24 hours with no apparent cause other than that of vascular origin
Ischaemic 85% and Haemorraghic 10-15%
What is the imaging of choice for a suspected stroke and why is this carried out before treatment?
CT
- Rule out bleeding (white) to confirm it is ischaemic and can start reperfusion therapy without causing more damage
- Also rules out alternative diagnoses of focal neurology
Why is reperfusion therapy only suitable in around 20% of patients?
- Patient may have bleeding tedency (anticoags, genetics, recent trauma or surgery)
- May be over the time frame of >4.5 hours
What is the NIHSS score?
Looks at 11 different areas (e.g dysphasia, gaze palsy, hemianopias, motor and sensory weakness, level of consciousness) to quantify impairment caused by a stroke, not diagnostic
Usually taken on the door and then after treatment to see if improved
How are strokes classified and how does each classification vary with their mortality?
What causes a TACS stroke and how does it present?
Proximal occlusion of a large artery e.g MCA or ICA causing ALL three of:
- Contralateral hemiplegia and/or sensory loss
- Contralateral hemianopia
- New disturbance of higher cerebral function (e.g aphasia, visuospatial problems/neglect)
What causes a LACS (lacunar) stroke and how does it present?
Occlusion of a single deep perforating artery, e.g lenticulostriate arteries. Often missed and high recurrence rate
- Pure motor loss OR
- Pure sensory loss OR
- Ataxic hemiparesis
What causes a PACS stroke and how does it present?
Occlusion of a branch of the MCA and needs 2/3 of the TACS criteria OR
- Higher cerebral dysfunction alone OR
- Monoparesis (weakness in one limb with no sensory loss)
What causes a POCS stroke and how does it present?
Occlusion of a posterior vessel (basilar, vertebral, posterior cerebral) leading to cerebellar, brain stem, occipital signs that presents with complexity due to decussation of tracts but one of:
- Ipsilateral CN palsy with contralateral motor and/or sensory deficit
- Disorders of conjugate eye movement
- Cerebellar dysfunction
- Isolated homonymous hemianopia or cortical blindness
After a patient has recieved their life-saving stroke treatment, what is done for them on the HASU ward?
PROMPT SECONDARY PREVENTION AND
- Swallow assessment in an hour to check for high risk aspiration
- Obs done every 15 mins
- Patient reviewed by OT, SLT, and Physio
- Maintain homeostasis (nutrition, blood presssure, oxygenation, glycemia)
- Treat and prevent complications (e.g secondary stroke)
What are the two methods of reperfusion therapy following an ischaemic stroke?
- Thrombolysis: alteplase (tPa) within less than 4.5 hours but can be safely administered up to 6 hours with ischaemic stroke
- Mechanical thrombectomy: can be used in conjunction with thrombolysis or when tPA is contraindicated. can be used up to 24 hours but better less than 6 hours
What is the most serious risk of reperfusion therapy?
HAEMORRAGHE (mainly intracerebral)
When are patients considered for mechanical thrombectomy?
- NIHSS >4
- Ischaemic stroke onset <6 hours
- Large vessel occlusion seen on CT angiogram
What happens with an ischaemic stroke if you do not treat it?
Black Infarction
What patient’s are considered for intravenous thrombolysis?
Give bolus dose then infusion over the next hour
What early secondary prevention measures are put into place after an acute ischaemic stroke?
- Aspirin or Clopidogrel (if in AF give anticoagulant such as deltaparin not antiplatelet)
- Statin
- Lower BP preferably <130/85
- Carotid surgery if carotid stenosis
How do we manage a haemorraghic stroke?
- Identify and reverse any coagulopathy (take clotting profile)
- Control BP (systolic <150mmHg)
- Consider neurosurgery if haemorraghe with hydrocephalus, lobar haemorraghe with GCS 9-12, cerebellar haemorraghe
What are some complications following a stroke and how do we prevent them from occuring?
- Pneumonia: sit up, safe swallow, early identification and treatment
- Seizures
- Pressure sores: position and turn
- Dehydration/Malnutrition: NG tube, IV fluids, dietician advice
- Conspitation/Incontinence/Retention: laxatives, hydration, enemas
- Depression
- DVT: IPCs
- Spasticity
What do you need to do in a stroke patient to prevent DVTs?
Give them intermittent pneumatic compression as elastic compression stockings do not work
What are the most common causes of ischaemic and haemorraghic strokes?
Ischaemic: cardioembolism (e.g AF and prosthetic heart valves), atherosclerotic thrombus, carotid artery dissection, vasculitis, venous sinus thrombosis
Haemorraghic: hypertension, AV malformation rupture, amyloid angiopathy, secondary ICH e.g from tumours
What are some differential diagnoses for a stroke like presentation?
- Focalseizure
- Space occupying lesion
- Pre-syncope
- Hypoglycaemia
- Migraine
Apart from doing a CT for this lady’s TIA, what other investigations can you do?
Likely to be TIA in left ACA as medial frontal lobe affected
- ECG for AF
- Carotid endarctectomy
- Lipid profile
- Blood pressure
What imaging modality is useful in TIA? What might you find?
MRI with DWI: Excludes alternative diagnoses
- In acute ischaemia - DWI positive lesions (bright white) with corresponding signal drop out (black holes) on the ADC map
What % of those with a TIA go on to have a stroke?
Around 20% within 90 days. Most within the first 48 hours, therefore early diagnosis and treatment is crucial.
What should you be looking for on a CT with an acute stroke patient?
What is the NIHSS used for?
- To assess the severity of a stroke and assess response to treatment
- Done intially, then at 1 hour, then at 24 hours
What are some clues in a patient history that point towards ICH over a ischaemic stroke?
- High BP
- Nausea and Vomiting
- Headache
What causes of stroke should be considered in younger stroke patients?
Same as in the older population (AF, hypertension, cholesterol etc…)
plus rarer causes:carotid/ vertebral dissection, vasculitis, thombophilia’s, genetic conditions, paradoxicalemboli from patent foramen ovale, illicit drugs
Which type of strokes cause headaches and why?
ICH: Blood is irritant to brain/ meninges. Oedema formation around the haematoma causes raised intracranial pressure.
POCS (ischaemic or ICH) – Acute inflammation and swelling within posterior fossa may block 4th ventricle and cause obstructive hydrocephalus
What vessel do most strokes originate from?
What percentage of people will regain full independence after a TACS?
What equipment helps to move patients from one bed to another after a stroke?
Hoist
