Vascular & Stroke Flashcards
Give three examples of antiplatelet drugs and their normal doses
Aspirin (75mg OD or 300mg acutely)
Clopidogrel (75mg OD or 300mg acutely)
Ticagrelor (90 or 60mg BD)
Dipyridamole
Give three examples of anticoagulants
Warfarin
Heparin
Enoxaparin / Dalteparin
DOACs - What clotting factors do
- rivaroxaban
- dabigatran
work on?
RivaroXaban - Xa
Dabigatran - IIa
What is the drug class and method of action of Aspirin?
Antiplatelet, and also analgesic and anti inflammatory (NSAID)
Irreversibly inactivates COX1. (Also affects COX 2).
What type of drug is alteplase?
How does it work? What is it used for?
Fibrinolytic agent - tissue plasminogen activator (TPA)
How does it work?
- activates plasminogen to form plasmin,
- which digests fibrin and fibrinogen,
- dissolving the clot.
Indications?
Thrombolysis :
- Acute ischaemic stroke
- MI if PCI not suitable/ unavailable
Future drug replacement - tenecteplase
What class of drug is tranexamic acid? Opposite of what drug?
Mode of action?
Do not give to what patient?
Antifibrinolytic agent (opposite to alteplase)
Inhibits plasminogen activation and this prevents fibrinolysis
Reduces haemorrhage
Don’t give to patients with massive haematuria as this may result in ureteric obstruction
Heparin - drug class? What factors? Indications? How is dosage decided?
Anticoagulant. Inhibits blood coagulation - primarily factors Xa and IIa (thrombin)
Indications - treats DVT, PE, unstable angina, acute peripheral arterial occlusion.
Dosage is adjusted according to the activated partial thromboplastin time (aptt).
Low molecular weight heparin - examples? Drug class? What factor? Advantages over normal heparin?
*I forget - no monitoring needed, less side effects.
Dalteparin, enoxaparin
Anticoagulant - inhibits blood coagulation. Inhibits factor Xa.
Advantages over heparin - longer half life, less side effects, no monitoring needed
Warfarin - class of drug? Mode of action? What clotting factors? Indications? Antidote?
Anticoagulant - inhibits blood coagulation
Vitamin K antagonist. Inhibits vitamin K epoxide reductase.
Affects clotting factors II, VII, IX and X.
Indications - AF, mechanical heart valves, PE/DVT.
Antidote - vitamin k, fresh frozen plasma (FFP), prothrombin complex concentrates (PCC).
Needs INR (prothrombin time) monitoring
DOACs - drug class? Which factors? Examples? Advantages?
Anticoagulants. Reduce clot formation. Dabigatran inhibits thrombin (factor IIa). Apixaban and rivaroxaban are direct inhibitors of factor Xa.
Advantages - easier to give (oral), no monitoring needed
Disadvantage - harder to reverse than warfarin, is possible but very expensive.
Drug options for prevention of DVT?
1st line
2nd line
LMWH Low molecular weight heparin eg Dalteparin
Or Fondaparinux - synthetic inhibitor of Xa. Anticoagulant. Similar to heparin.
Drug treatments for DVT?
LMWH
Or DOAC
Or LMWH + warfarin
What is the medicine prescribed for ischaemic stroke?
What about if allergic to primary treatment?
What if already on primary treatment?
Aspirin 300mg daily for 2 weeks. Then switch to clopidogrel 75mg daily.
Or clopidogrel 300mg loading if aspirin allergic
Or dual antiplatelet eg aspirin and clopidogrel/ticagrelor, if already on aspirin
What is the medical treatment for a cardioembolic stroke? (AF is the cause)
DOAC eg apixaban
Or warfarin - if mechanical heart valve, renal failure.
Name some functions of the brain stem (5) and cerebellum (2)?
Name the four cerebral cortices and their functions (2,1,5,1)
Frontal
- movement
- executive function
Parietal
- sensory info
Temporal
- hearing
- smell
- memory
- languages
- facial recognition
Occipital
- vision
The left and right vertebral arteries join together to form the ________ artery which supplies the __________ and _________. The _______ artery then gives off the ________ _________ arteries which mainly supply the _________ lobe.
Basilar
Cerebellum, brain stem
Basilar
Posterior cerebral
Occipital lobe
The internal carotid arteries turn into the left and right ______ ______ arteries which serve the _______ portions of the ______, ______ and ______ lobes of the brain.
The internal carotid arteries also give off branches called the _______ _______ arteries which serve the ______ portion of the ______ and _______ lobes, and connect with each other via the _______ _______ artery.
Middle cerebral
Lateral
Frontal, parietal and temporal
Anterior cerebral
Medial
Frontal and parietal lobes
Anterior communicating artery
Causes of intracerebral haemorrhage? (6) which most common?
Hypertension (most common)
Arteriovenous malformations *
Vasculitis
Vascular tumours
Cerebral amyloid angiopathy
Can be secondary to ischaemic stroke (bleeding into dead tissue - haemorrhagic conversion)
*A tangle of blood vessels that directly connect an artery to a vein
What are the 6 P’s of acute limb ischaemia?
Commonly caused by?
What scan to diagnose?
Treatment?
Pain
Pulselessness
Pallor
Paraesthesia
Paralysis
Perishingly cold
(If movement and sensation are lost these are signs leg is unsalvaeable - very late signs)
Thromboembolism
CT angiography
Treatment: Heparin bolus/infusion, surgery to revascularise the limb within 4/6 hours. If too late - amputation.
Surgical options:
- Angioplasty (balloon +- stenting)
- Embolectomy with Fogarty catheter
- Local intra-arterial thrombolysis
- Bypass graft
- Amputation
What are the clinical features of TACS - total anterior circulation syndrome?
What artery is usually affected?
See below
Middle cerebral artery
What are the clinical features of PACS?
What artery usually affected?
Branch of Middle cerebral artery
What are the clinical features of POCS?
Usual artery affected?
(4)
See below
Occlusion of one of
- vertebral
- basilar
- cerebellar
- posterior cerebral artery
What are the clinical features of a lacunar stroke?
What artery could be affected?
Usually cause?
See below
Small penetrating artery such as a branch of MCA or supply to brain stem or deep white matter
Usual cause is hypertension - small vessel disease
In which hemisphere is the language centre normally located?
Names of the two locations?
Left hemisphere (but sometimes left handed people have it on the right)
Broca’s area
Wernicke’s area
Damage can cause
- acquired dyslexia (reading)
- acquired dysgraphia (writing)
- expressive aphasia (speaking)
- receptive aphasia (auditory comprehension)
What difficulty is associated with Wernicke’s area?
What lobe is Wernicke’s area?
Receptive aphasia. Aka fluent aphasia. Difficulty understanding, and may be fluent but not make sense (case study - Byron)
Parietal lobe
What difficulty is associated with Broca’s area?
What lobe is Broca’s area in?
Expressive aphasia. Aka non-fluent aphasia. Difficulties with producing language. Case study - Sarah Scott.
Frontal lobe
What is dysarthria?
A problem producing and forming the words because of weakness.
Causes by weakness of the muscles of the face, mouth and breathing. May also have problems with drooling and food pocketing in the side of the mouth.
Not a problem with understanding speech or finding speech.
Case study - Jim and Christine (locked in syndrome).
What is apraxia of speech (AOS)?
Apraxia - brain knows the words, but has problems communicating them to the mouth. No word finding difficulty but just a delay from brain to mouth. Speech is slow.
Pathways between motor cortex and facial muscles have been disrupted resulting in difficulties with motor speech planning.
Case study: Gina
What drugs can be used for spasticity after stroke?
Baclofen
Tizanidine
Gabapentin
Botulinum toxin
When does a AAA need surgery? (3)
5.5cm or larger.
> 1cm growth in last year
Or smaller but symptomatic eg. Rupture, pain, embolisation (6 P’s, blue toe syndrome)
AAA - open repair vs EVAR. List a couple of pro’s for each method.
Which is better for younger, fitter patients?
Pros of Open repair (better for younger, fitter patients as it lasts better )
- lower late mortality
- less expensive
- less exposure to X-rays and contrast than EVAR
Con - worse immediate mortality 2% vs EVAR <1%
Pros of EVAR (better for older, less fit patients)
- lower early mortality
- doesn’t need HDU
- shorter hospital stay
- shorter recovery, due to keyhole groin method.
Con - lifelong surveillance required
What is the difference between true and false aneurysms?
How does an epidural haematoma look on a CT scan?
Biconvex shape (both sides curved)
Hyperdense region (white)
Does not cross suture lines
What is the diagnosis?
Skull fracture with epidural haematoma
What are the differences between epidural and subdural haemorrhages?
What is the location of an epidural haematoma?
Commonest cause?
Commonest site?
Above the dura mater - between the dura mater and the skull
Head trauma
Above meningeal artery at the pterion
What are the three layers of the meninges? From outermost to innermost.
Dura mater
Arachnoid mater
Pia mater
What are the symptoms of an epidural haematoma?
What are the features of an arterial ulcer?
Small
Deep
Punched out margin
Do not bleed / ooze (dry)
Occur distally eg. toe tips, lateral malleolus
Painful
Loss of hair on skin surface
Pale and shiny skin
Might have intermittent claudication
Peripheral pulses may be absent
Pain at night when legs elevated, relieved by hanging feet off the bed
What are the features of a venous ulcer?
Large
Shallow
Sloping edges
Bleed/ ooze (wet)
Gaiter area - often medial side
Not painful
Occur with haemosiderin deposition
Lipodermatosclerosis - fibrosis of subcutaneous fat results in fibrosed and thickened skin
Erythematous
What are the three features of critical limb ischaemia?
Typical ABPI reading?
Ischaemic pain at rest
Arterial ulcers
Gangrene
ABPI < 0.5
What type of stroke does a patient have if their only symptom is isolated higher cortical dysfunction eg aphasia?
What artery is likely affected?
PACS - partial anterior circulation syndrome
Middle cerebral artery
What is the ROSIER score for and what are the criteria to score positive points (5) and negative points (2)?
ROSIER = Recognition Of Stroke In the Emergency Room
ROSIER helps calculate likelihood patient has had a stroke.
What does the ABCD2 score measure? What are the criteria? What score is low/medium/high risk?
ABCD2 score is used with TIA patients - to assess the risk of stroke after TIA.
1-3 low risk
4-5 medium risk
5-7 high risk
A high score would be referred to a specialist sooner.
Type of scan?
What does it show?
Associated symptoms?
CT Brain
Subarachnoid haemorrhage (SAH) ‘star sign’ of white star in the middle
Can also show as blood in the ventricles which will gather at the posterior of the head due to gravity / supine position
Thunderclap headache
What does this CT brain show?
Symptoms?
ICH - intracerebral haemorrhage
Description - large Hyperdense (white) region in right hemisphere, with effacement of sulci and ventricles and midline shift
Likely associated symptoms - headache and hemiparesis, worsening level of consciousness. Probable history of hypertension
What does this scan show?
What are the likely associated symptoms?
CT brain - right sided infarct with haemorrhagic transformation
What does this CT brain show?
LEFT acute infarct with dense MCA sign
Dense MCA sign is where the middle cerebral artery appears white - Hyperdense - due to a thrombus.
Infarcted area appears as hypodense.
What does this scan show?
What artery supplies this region?
Hypodense region on the right side indicating old infarct
MCA - middle cerebral artery
What does this CT brain show?
Left sided old lacunar infarcts
from radiologymasterclass.co.uk CT brain gallery
What does this CT brain show?
Left sided extradural haematoma (EDH) also called epidural haematoma / haemorrhage, with contracoup injury
What does this scan show?
Bilateral SDH - subdural haematoma. (Crescent shaped) with re bleeding
What area of the brain does a lacunar stroke usually occur in?
Usually in a deep area of the brain rather than the outer cerebrum (eg. thalamus, basal ganglia, pons, deep areas of white matter).
In the Rutherford classification for acute limb ischaemia, name and describe types I, IIa, IIb and III. How treatable are they?
https://teachmesurgery.com/vascular/peripheral/acute-ischaemia/
Which area of the brain is supplied by the anterior cerebral artery?
And the middle cerebral artery?
and the posterior cerebral artery?
The anterior cerebral artery (ACA) supplies the MEDIAL areas of the FRONTAL and PARIETAL lobes
The middle cerebral artery (MCA) supplies the lateral areas of the frontal, parietal and temporal lobes.
The posterior cerebral artery (PCA) supplies the occipital lobe.
Which vascular territory of the brain do lacunar strokes usually occur in?
The MCA perforator territory
Lacunar strokes often occur quite deep in the brain, in a perforating branch of the middle cerebral artery.
What level of the brain is this head CT taken at?
Name the vascular territories involved.
What does VBA supply?
At the level of the cerebellum.
What are the names of the meningeal layers of the brain? What order are they from outer to inner brain?
At what level do these bleeds occur:
- Extradural haemorrhage (EDH)
- Subdural haemorrhage (SDH)
- Subarachnoid haemorrhage (SAH)
- Intracerebral haemorrhage (ICH)
Dura mater
Arachnoid mater
Pia mater
EDH aka. epidural haematoma - outside the dura, between the dura mater and the skull (usually results from tears in arteries)
SDH - Underneath the dura, between the dura mater and arachnoid mater (usually results from tears in bridging veins)
SAH - Bleeding into the subarachnoid space, between the arachnoid mater and pia mater
ICH - Bleeding into the cerebrum (haemorrhagic stroke)
CT brain, superior slice - where are the borders between the lobes?
What are the classifications of aortic dissection?
How are the different types generally managed?
STANFORD and DEBAKEY classification systems are used for lassification of aortic dissections
Stanford Type A: Involves the ascending aorta, arch of the aorta. Proximal to left subclavian artery. (A Affects Ascending Aorta!)
Stanford Type B: Involves the descending aorta.Distal to left subclavian artery origin.
___________________________
Type A dissections are generally managed SURGICALLY as they may result in coronary artery occlusion, aortic incompetence, or rupture into the pericardial sac with resulting cardiac tamponade.
Type B dissections are generally managed MEDICALLY with blood pressure control.
____________________________
The DeBakey classification divides dissections into three types:
type I: involves ascending and descending aorta (= Stanford A)
type II: involves ascending aorta only (= Stanford A)
type III: involves descending aorta only, commencing after the origin of the left subclavian artery (= Stanford B)
https://doctorguidelines.com/2017/06/28/acute-aortic-dissection/
What are the 4 H’s and 4 T’s that cause cardiac arrest?
Ones I forget - hypothermia, hypovolaemia, thrombosis, tension pneumothorax
Name the vessels
Name the vessels
Is this left or right leg?
Right leg
