peripheral arterial disease

Question 1

what is peripheral vascular disease?

Answer 1

branching term that refers to any disease of the vasculature and circulation, including arteries and veins.

Question 2

what is peripheral arterial disease?

Answer 2

disease of arterial supply, usually narrowing or blockage of arteries -sometimes people say PVD when they really mean PAD.

Question 3

what is the pathophysiology of PAD?

Answer 3

progressive narrowing of the peripheral arteries of the limbs
most commonly caused by atherosclerosis
can cause claudication or ischaemia, increases risk of thrombus formation in arteries increasing risk of acute limb ischaemia.

Question 4

what are the main blood vessels supplying the leg (starting with the aorta)?

Answer 4

aorta -common iliac arteries -internal (supplies pelvic structures) and external iliac arteries -external becomes femoral (muscles in thigh and groin) -becomes popliteal -splits into anterior and posterior tibial arteries -posterior can feel as posterior tibial pulse -anterior continues as dorsalis pedis

Question 5

what are the risk factors for PAD?

Answer 5

atherosclerosis risk factors: smoking, HTN, diabetes, hyperlipidaemia, sedentary, obesity, age, family history

Question 6

what are the symptoms and signs of PAD?

Answer 6

intermittent claudication
reduced pulses
coolness
paleness
dry itchy skin
poor nail growth
poor/absent hair growth
increased CRT

Question 7

what is intermittent claudication and its presentation?

Answer 7

claudication =pain from tissues caused by insufficient blood supply to reach tissues’ needs
typical early sx =aching/cramping in buttocks, thigh, calf, or foot
pain ends to be induced by exertion and typically has a ‘claudication distance’ where walking a specific distance induces the pain.
pain doesn’t improve when trying to ‘power through’ but quickly relieved by rest

Question 8

what are 2 ways to stage severity of PAD?

Answer 8

fontaine classification
rutherford classification

Question 9

what is the fontaine classification of PAD?

Answer 9

1-asymptomatic
2-intermittent claudication
3-ischaemic rest pain
4-ulceration +/- gangrene -this is progression to critical limb ischaemia

Question 10

what is the rutherford classification of PAD?

Answer 10

stage 0-asx
stage 1-mild claudication
stage 2-moderate claudication
stage 3-severe claudication
stage 4-rest pain
stage 5-ischaemic ulceration not exceeding digits of the foot
stage 6-severe ischaemic ulcers/frank gangrene

Question 11

what is a bedside test you can do to determine whether someone has PAD?

Answer 11

buerger’s test
lift leg up (obvi check if hip/leg pain first) up to 90 degrees and leg should stay pink and perfused. angle at which leg starts to go pale =buerger’s angle. <20 degrees=severe ischaemia. patient is then asked to sit up and swing legs over edge of bed-in patients with ischaemia the leg will turn a red colour due to reactive hyperaemia (reperfusion after a short period of ischaemia)

Question 12

what test confirms diagnosis of PAD?

Answer 12

ABPI (ankle brachial pressure index)

Question 13

how do you do ABPI ?

Answer 13

Bp of lower limb (posterior tibial or dorsalis pedis-highest one)/BP of brachial
use doppler and put it over pulses instead of listening with stethoscope

Question 14

what do ABPI measurements mean?

Answer 14

• <0.5=severe arterial disease -critical limb ischaemia
• 0.5-0.8=moderate arterial disease
• 0.8-0.9=mild PAD
• 0.9-1.2=no evidence of significant PAD
• > 1.2=calcified vessels causing unusually high ABPI results -needs further assessment -usually due to diabetes

Question 15

bloods for PAD?

Answer 15

FBC
U+E
coag
lipid profile
hba1c
fasting BM

Question 16

bedside tests for PAD?

Answer 16

pulses
buerger’s test
BM
ECG
BP
ABPI

Question 17

what is a duplex scan?

Answer 17

combination of doppler and traditional USS which produces dynamic image of blood flow through arteries or veins. can show sites of occlusion/stenosis.

Question 18

what is the gold standard imaging for assessing arteries in PAD?

Answer 18

digital subtraction angiography (DSA)
pre-contrast image acquired then subtracted from subsequent post-contrast images, using fluoroscopy. produces images of blood vessels without interfering shadows from overlapping tissues and allows for lower dose of contrast medium. done through femoral catheter insertion and can be used for treatment as well (diagnostic and therapeutic)

Question 19

what are the types of management options for PAD?

Answer 19

conservative
medical
surgical

Question 20

what are the conservative managements for PAD and when would you do conservative management?

Answer 20

mild to moderate disease
supervised exercise programme: everyone with PAD needs to be offered this
secondary prevention of CVD: smoking, drinking, diet, physical activity, control diabetes
education and safety netted

Question 21

what is the NICE management pathway of PAD?

Answer 21

-conservative -above
-modification of CV risk: clopidogrel recommended for all patients with PAD, QRISK and statins
-refer for angioplasty or bypass surgery when exercise hasn’t improved it enough and all risk factors have been modified.
-if person doesn’t want surgery -naftidrofuryl oxalate (vasodilator) for 3-6 months and discontinue if no benefit

Question 22

what happens in an angioplasty for PAD?

Answer 22

balloon catheter passed into stenosed artery with help of guide wire, usually through femoral artery. balloon blows up and pushes occlusion out. sometimes stents are inserted.

Question 23

what happens in a bypass surgery for pad?

Answer 23

grafts are made using either patient’s own vein or PTFE (organic compound) graft
grafts are anastomosed to bypass the blocked artery.

Question 24

what situations are bypasses used in pad?

Answer 24

more invasive -prefer angioplasty
reserved for patients with diffuse disease able to undergo general anaesthetic

Question 25

when is amputation used for pad?

Answer 25

when there are no options for revascularisation and the extent of the ischaemia is causing incurable sx or gangrene causing sepsis.

Question 26

what is critical limb ischaemia defined as?

Answer 26

severe rest pain for >2 weeks or development of ulcers/gangrene.

Question 27

what is acute limb ischaemia?

Answer 27

new event (usually plaque rupture or embolus) that cuts off arterial supply acutely, symptoms are sudden onset and present for <2 weeks.

Question 28

what are the clinical features of acute limb ischaemia?

Answer 28

6Ps: pallor, pulseless, painful (earlier signs), paraesthesia, perishingly cold, paralysis

Question 29

what is the management of acute limb ischaemia?

Answer 29

immediate referral to vascular team for potential intervention

Question 30

what are the signs that a limb is not salvageable during acute limb ischaemia?

Answer 30

fixed mottling
cyanosis
fixed plantar flexion
no sensation

Question 31

what are the characteristics of arterial ulcers and where are they found?

Answer 31

punched out and deep, irregular shape, presence of necrotic tissue, minimal exudate, clear borders. like a black hole
found in lateral malleolus, tibial areas, pressure points, toes, and feet