Vascular Flashcards
What is PAD (peripheral arterial disease)
narrowing of arteries supplying the limbs & peripheries, reducing blood supply to these areas
results in symptoms of claudication, most common in the lower legs
define ischaemia
inadequate oxygen supply to the tissues due to reduced blood supply
complications of atherosclerosis
stenosis = reduced blood flow e.g angina
stiffening of the artery walls = hypertension & strain on heart trying to pump against increased SVR
plaque rupture = thrombus & ischaemia
co-morbidities that increase risk of atherosclerosis
diabetes
HTN
CKD
Inflammatory conditions e.g. RA
Atypical antipsychotic medications
risk factors for atherosclerosis
non-modifiable: older age, male, FHx
modifiable: smoking, alcohol, sedentary lifestyle, poor diet, poor sleep, stress
presentation of PAD
intermittent claudication
crampy pain in the calf**, thigh, and buttocks that occurs after walking a certain distance
after stopping & resting, the pain will disappear
end results of atherosclerosis
angina
MI
TIA/stroke
PAD
chronic mesenteric ischaemia
what is critical limb ischaemia
end stage of PAD
inadequate blood supply to the limb to allow it to function normally at rest
Results in pain at rest, non-healing ulcers, and gangrene
significant risk of losing the limb
features of critical limb ischaemia
6 Ps
Pain, pallor, paraesthesia, pulselessness, perishingly cold, paralysis
burning pain, worse at night when the leg is raised as gravity is no longer helping pool blood in the foot
examination findings for PAD
inspection: tar staining on fingers, xanthomata, missing limbs/digits, sternotomy scar or scar on inner calf for CABG, focal weakness suggestive of previous stroke
weak peripheral pulses (might need to use a handheld doppler)
pallor, cyanosis, ulcers, hair loss, poor wound healing, reduced skin temp, prolonged CRT, +ve Buerger’s test
what is Buerger’s test
1st part: lying patient supine, lifting leg to 45 degree angle & hold for 1-2 mins checking for pallor
2nd part: sit patient up with legs hanging over the side of the bed. Blood will flow back into legs assisted by gravity. In a healthy patient, legs will remain a normal pink colour
PAD: blue initially as ischaemic tissue deoxygenates the blood, then dark red due to vasodilation in response to waste products of anaerobic respiration
*** dependant rubor
what causes a leg ulcer
indicates the skin and tissues are struggling to heal due to impaired blood flow
arterial: ischaemia due to inadequate blood supply
venous: impaired drainage & pooling of blood in the legs
difference between arterial and venous ulcers
arterial: smaller, deeper, well-define borders, ‘punched out’ appearance, occur peripherally e.g. on the toes, reduced bleeding, painful
venous: larger, more superficial, irregular gently sloping borders, less painful, affect mid-calf down to the ankle, other signs of venous insufficiency e.g. haemosiderin staining, venous eczema
Investigations for PAD
ABPI
Duplex USS (speed & volume of the blood)
Angiography
how to calculate ABPI
ratio of systolic BP in the ankle compared to systolic BP in the arm
left & right brachial artery pressure: take the highest
tibialis posterior & dorsalis pedis for each foot: take the highest
highest foot pulse on each foot/highest arm pulse overall
ABPI value interpretation
0.9 – 1.3 is normal
0.6 – 0.9 indicates mild peripheral arterial disease
0.3 – 0.6 indicates moderate to severe peripheral arterial disease
Less than 0.3 indicates severe disease to critical ischaemic
> 1.3 can indicate calcification of arteries, making them difficult to compress
more common in diabetic patients
management of intermittent claudication
lifestyle changes - stop smoking!
optimise medical treatments of co-morbidities
exercise training: regularly walking to the point of near-maximal claudication and pain, resting & repeating
atorvastatin 80mg
clopidogrel 75mg
naftidrofuryl oxalate: vasodilator sometimes used for patients with a poor quality of life
surgical:
endovascular angioplasty & stenting (might not be suitable for more extensive disease)
endarterectomy (cutting vessel open & removing the plaque)
bypass surgery
define angioplasty
using a balloon to stretch open a narrowed or blocked artery
management of critical limb ischaemia
require urgent referral to vascular team
urgent revascularisation by:
endovascular angioplasty & stenting
endarterectomy
bypass surgery
amputation if not possible to restore blood supply
what is acute limb ischaemia
rapid onset of ischaemia in a limb
typically due to a thrombus blocking arterial supply in a distal limb
management of acute limb ischaemia
endovascular thrombolysis
endovascular thrombectomy
surgical thrombectomy (cutting vessel open rather than inserting a catheter)
endarterectomy
bypass surgery
amputation
what is Leriche syndrome
occurs with occlusion in the distal aorta/proximal common iliac artery
triad: thigh/buttock claudication, absent femoral pulses, male impotence
what is chronic venous insufficiency
blood does not efficiently drain from the legs back to the heart, usually the result of damage to the valves inside the veins (age, immobility, obesity, prolonged standing)
associated with varicose veins!!
what area of the leg is most commonly affected in chronic venous insufficiency
gaiter area
- between the top of the foot & bottom of the calf muscle
presentation of chronic venous insufficiency
chronic pooling of blood leads to skin changes:
haemosiderin deposition (Hb leaking into skin)
venous eczema (dry, itchy, flaky, red, cracked skin caused by chronic inflammatory response in the skin)
lipodermatosclerosis (tightening of skin & tissue beneath the skin, chronic inflammation causes fat to become fibrotic)
narrowing of legs causes typical inverted champagne bottle appearance
atrophie blanche (patches of smooth porcelain white scar tissue on skin often surrounded by hyperpigmentation - occur after an ulcer heals)
can also lead to:
cellulitis
poor healing after injury
ulcers
pain
management of chronic venous insufficiency
