Vascular Flashcards
What is peripheral arterial disease? What is it caused by?
- Describes narrowing or occlusion of the peripheral arteries, affecting the blood supply to the lower limbs
- Peripheral arterial disease of the lower limbs is most commonly caused by atherosclerosis which narrows the affected arteries limiting blood flow to the affected limb
Risk factors for peripheral arterial disease?
- Same as those for atherosclerosis
- Main ones are smoking and diabetes
- Others: hyperlipidaemia, hypertension, obesity, diet high in fats, age, family history
3 presentation of peripheral arterial disease?
acute limb ischaemia, chronic limb ischaemia, chronic limb threatening ischaemia
What is acute limb ischaemia, what is the cause of most?
- Sudden decrease in limb perfusion that threatens limb viability (develops over less than 2 weeks)
- 80% are due to embolic events
Presentation of acute limb ischaemia? Describe the colours the legs go?
- 6Ps: pain, pallor, paraesthesia, paralysis, perishingly cold and pulselessness
- Legs will first be white, then capillaries fill with stagnant cyanotic blood (mottling) which blanches on pressure, if reperfusion is not achieved arteries thrombose and capillaries rupture so there is fixed blue staining of the skin which does not blanch on pressure
Investigations for acute limb ischaemia?
- Investigations: FBC, UandE, coag screen, ECG, imaging for all patients in which amputation is not inevitable – CTA first line
Management of acute limb ischaemia?
- Management: O2, IV and fluid resus, foot down tilt, unfractionated heparin, revascularisation surgery
Presentation of chronic limb ischaemia?
- This presents as intermittent claudication (diminished circulation leads to pain in the lower limb on walking or exercise that is relieved by rest
- May also have non healing wounds on the lower limb
Diagnosis of chronic limb ischaemia?
- Diagnosis is made on presence of clinical features and ABPI
Management of chronic limb ischaemia?
manage CV risk, advice on smoking cessation, supervised exercise programme, referral for consideration of angioplasty/ bypass, consideration of naftidrofuryl oxalate if not been satisfactory improvement and doesn’t want referral for surgery
What is meant by chronic limb threatening ischaemia?
- Chronic inadequate tissue perfusion at rest, ischaemic rest pain, with or without tissue loss
Management of chronic limb threatening ischaemia?
- These people need urgent referral to vascular MDT
Vascular claudication vs neurogenic claudication?
- Neurogenic claudication can also be relieved by leaning forward
- Vascular pain tends to be more predictable, a patient can walk x distance before the pain comes on, neurogenic is more random
- vascular pain tends to be more of a crampy pain, neuorgenic is more burning/ shooting (not always though)
- vascular pain is more distributed in the calves, neurogenic pain distribution will depend on nerve roots affected
- Vascular claudication will have signs like potential pallor, unhealing wounds
What is naftidrofuryl ?
- This is a vasodilator and also enhances cellular oxidative capacity
What is an aneurysm
- Aneurysm can be defined as focal dilatation of a blood vessel > 1.5x its normal diameter
Explain what is meant by true and false aneurysm
- A true aneurysm involves all three vessel wall layers
- False aneurysms or pseudoaneurysms occur when the intimal and medial layers are disrupted and the dilated segment is surrounded by the adventitia only
Are AAA aneurysms usually true or false
usually true - * AAA is the most common true arterial aneurysm, false aneurysms of the abdominal aorta are usually due to trauma or infection
Risk factors/ what groups get AAA?
- More common in older men
- 1 in 70 men over 65 yrs have a AAA
aetiology is largely unknown - Risk factors include smoking, hypertension, hyperlipidaemia, FH, male gender and increasing age
- Diabetes decreases risk but mechanism is poorly understood
Are AAA usually symptomatic?
- Unruptured aneurysms are generally asymptomatic and may only be an incidental finding or detected on screening
- Small subset present with triad of lower back pain, weight loss and raised ESR
- Most people are symptomatic because they have had a rupture or distal embolisation
Rupture AAA presentation?
- Classic triad of a ruptured aneurysm is abdominal/ back pain, hypovolaemia and pulsatile abdominal mass but this triad is relatively rare
- May be groin pain/ syncope/ paralysis/ flank mass
- Can get rupture into the vena cava or iliac vein, this leads to tachycardia, CHF, leg swelling, abdominal thrill, abdominal bruit, renal failure and peripheral ischaemia
- Can also cause a GI bleed
Embolism AAA presentation?
- AAA can through off embolisms
- These people may develop acute limb ischaemia or “blue toe syndrome”
Explain management of unruptured AAA?
- Any AAA less than 5.5cm can be monitored via Duplex USS as surgery prior to this diameter provides no survival benefit, cardiovascular risk factors should be modified as appropriate
- Surgery in unruptured should be considered in those who are: symptomatic, asymptomatic but it’s larger than 4.0 cm and grown by more than 1cm in 1 year or in those where it is asymptomatic and 5.5cm or larger
- Aneurysms can either be repaired by open repair (cut open and the aneurysm part removed and replaced with a prosthetic graft) or by endovascular repair (introduce a graft via the femoral arteries and fixing the stent across the aneurysm)
- Both have good long term outcomes but endovascular has better hospital stay outcomes, although endovascular repair may need more reinterventions and have more ruptures
Management of ruptured AAA?
- ABCDE
- If patient unstable they get immediate transfer to theatre for open surgical repair
- If they are stable they get a CT angiogram to determine whether the aneurysm is suitable for endovascular repair
Explain screening for AAA?
- Men in their 65th year are invited to be screened by ultrasound of abdomen
- If no aneurysm men are not invited back for further screening
What are 3 acute aortic conditions affecting the thoracic aorta?
- Aortic dissection
- Intramural haematoma (IMH)
- Penetrating aortic ulcer (PAU)
All three conditions may co-exist and IMH and PAU may lead to dissection