Management of Vascular Disorders Flashcards
What is the pathophysiology causing peripheral vascular diseases/problems?
Atherosclerosis
What is the definition of atherosclerosis?
Hardening of the arteries
What other systemic diseases often overlap in patients with peripheral arterial disease?
Coronary disease
Cerebrovascular disease
Diabetes
Kidney disease
What is claudication?
Pain in the leg on walking due to blocked or narrowed arteries
What is the physiology of claudication?
When the arteries are narrowed, less oxygen is delivered to muscles, which then undergo anaerobic metabolism leading to an abnormally rapid build-up of lactic acid in the muscles causing local pain in that muscle group (particularly the calf muscles)
What are some key questions to ask that can help make the clinical diagnosis of claudication?
Does the pain ever occur standing still or sitting? (No because not using muscles)
Is it worse if you walk uphill or hurry? (Yes because more lactic acid is produced)
What happens to it if you stop and stand still? (It goes away within a few minutes as lactic acid gets washed away and oxygen debt is repleted)
Where do you feel the pain or discomfort? (Typically calf muscles, atypically thigh or buttock muscles, definitely not in foot or toes)
How to diagnose claudication?
Typical history
Examination for absent pulses
Exclusion of other conditions (eg arthritis in hip or knee)
Measure blood pressure in the legs using hand-held doppler (Ankle-brachial pressure index <0.9 is diagnostic for presence of PAD)
Vascular imaging with CT or MR (magnetic resonance) angiography or Duplex Doppler scanning
What to ask when assessing vascular history?
Myocardial infarction/angina/heart failure
Stroke/TIA
Diabetes
Smoking and other risk factors
Social circumstance/quality of life
Medications
What is the 5-year fate of untreated claudication (MI, other causes, amputation)?
20% die of MI
10% die of other causes
3% amputation
What are the medical therapy options available to manage patients with peripheral arterial disease?
Blood pressure control
Lipids control
Antiplatelet (Clopidogrel/aspirin)
Angiotensin-converting enzyme inhibitor (ACEI)
Diabetes control
What lifestyle changes can be made to help reduce the symptoms of the peripheral arterial disease?
Stop smoking
Exercise - walking
Weight reduction
Improved diet
What is critical ischaemia?
Ischemia that is severe enough to threaten the loss of the limb or part of the limb (amputation)
What are the clinical features of critical ischaemia?
Rest pain (not just when walking)
+/- gangrene or ulcers
Doppler pressures in foot <50mmHg
What are the symptoms of vascular rest pain due to critical ischaemia (different from pain in claudication)?
Felt in toes/foot
Often severe
Worse at night
Hang foot out of bed or sleeps in a chair (gravity)
What is most likely to happen to patients with critical ischaemia if nothing is done?
Amputation
What is the priority for patients with critical ischaemia?
Revascularisation to unblock or bypass diseased vessels
What can be done to investigate the sites of blockage?
Duplex scan (non-invasive)
Angiogram
Computed tomography angiography (CTA) or magnetic resonance angiography (MRA)
What are the two urgent revascularisation procedures that patients with critical ischaemia can undergo?
Balloon angioplasty
Bypass surgery (FemPopliteal/Aortofemoral/Axillo-femoral)
What does acute mean in acute ischaemia of the leg?
Sudden onset
What are the major causes of acute ischaemia of the leg?
Thrombosis
Embolism
What are some rare causes of acute ischaemia of the leg?
Trauma
Extrinsic compression
Severe venous obstruction
Low flow states/vasospasm
Vasoconstrictor drugs
What are the sources of emboli?
Heart
Arteries
Veins
Tumours
Foreign bodies
What causes a thrombus to form in the heart?
Atrial fibrillation
Myocardial infarction
Valve disease
What causes an embolus to appear in the arteries?
Aneurysms (aorta/popliteal/thoracic)
Stenoses
Which group of cells are more sensitive (start to die off) to acute leg ischaemia - nerves/muscle or skin/subcutaneous tissue?
Nerves/muscle
Because of the relatively poor ability of the muscle and nerve cells to cope with prolonged ischaemia, acute leg ischaemia needs to be treated as _________ ___________, and blood flow needs to be restored within __ to __ hours if the limb is to be saved.
Surgical emergency
4 to 6
What should be given immediately to patients with acute leg ischaemia?
Heparin
What is the surgical procedure of removing an embolus called?
Embolectomy
What are the clinical features (5Ps) of acute leg ischaemia?
Pain in leg - severe initially then decreases as nerves stop working
Pale/cold leg
Pulseless
Paralysis - can’t stand/walk
Paraesthesia/numbness - can’t feel leg
How to manage patients with acute leg ischaemia?
Give heparin/analgesia immediately
Resuscitate - ABC
Catheter/central venous pressure (CVP) line
Surgery as emergency - embolectomy or bypass
Amputation if too late
Why is heparin given to patients with acute leg ischaemia?
To stop the propagation of any thrombus that will make the situation worse
What does aneurysm (from the Greek word aneurysma) mean?
Widening (of the aorta)
What is the diameter of the aorta to be classified as (AAA) abdominal aortic aneurysm?
3cm and above
What is the best screening test for abdominal aortic aneurysm?
Ultrasound scan (or sometimes CT scan)
Aortic aneurysms are most common in ____ over ______ years old.
Men, 65
What causes an increased risk of aortic aneurysms?
Smoking
Hypertension (high blood pressure)
Are aortic aneurysms common in women?
No
Abdominal aortic aneurysms of <___cm in diameter are usually managed conservatively (regular ultrasound scans) as the risk of _________ is low.
5.5, rupture
How are abdominal aortic aneurysms of >5.5cm diameter usually treated?
Open repair surgery or stenting
What will happen to patients with ruptured aneurysms if not taken to theatre for surgery immediately?
Die
How is the open surgery for abdominal aortic aneurysm traditionally done?
Through laparotomy (abdominal incision)
What does the less invasive radiological technique that can be used to repair aneurysms (endovascular aortic aneurysm repair) involve?
A stent graft is inserted from the femoral arteries at the top of the legs and the groins up to the inside of the aneurysm to seal the blood vessel so blood can flow through the stent graft as normal.
All men at ___ years old in England are offered _________ scan screening for abdominal aortic aneurysm. AAA can be _____, but can be ______ if detected early.
65, ultrasound, fatal, repaired
Why is ultrasound technique used to screen AAA?
Simple and safe
No radiation exposure
Sensitivity and specificity are nearly 100%
Cost-effective
Has reduced ruptured AAAs
1 in __ strokes are due to carotid disease
6
Carotid disease usually causes TIA and strokes by:
Mainly embolisation of atherosclerotic debris from plaques or thrombus
And occasionally by restriction of flow when the stenosis gets very tight or when the internal carotid artery gets blocked
We intervene in patients with strokes or TIAs associated with internal carotid _________ around 70% or more
Stenosis
TIA = a ____ stroke. Resolves within ____ hours. Can affect ______, ______ or ______ commonly.
Mini, 24, vision, speech, limbs
What is the main danger of aortic aneurysms?
Rupture
What is the typical first line of investigation for carotid disease?
Ultrasound
Why is stenting of carotid artery stenosis, which has been proven to reduce stroke and death rates, not the preferred treatment usually?
Has a higher incidence of causing embolic problems
What is the best operation for preventing strokes caused by carotid artery stenosis?
Carotid endarterectomy
When would stenting be the better option than carotid endarterectomy (involves making an incision of the side of the neck over the affected carotid artery) for treating carotid artery stenosis?
Previous major head and neck surgery
Neck irradiation
