Peripheral Arterial Disease Flashcards
(28 cards)
What is the underlying process that causes PAD?
Atherosclerotic disease- 65% have co-existing cerebral and coronary artery disease
What are some of the symptoms of PAD?
Intermittent claudication- there is pain on exertion in the area supplied by the diseased vessel
Ulceration
Hair loss
Pain on elevation of the leg
Describe the nature of intermittent claudication and the processes underlying it
Pain is brought on by exertion as the diseased vessel lumen is not large enough to meet the demands during exercise. This results in ischaemia distally which causes pain.
Which area of the body is most commonly affected by PAD?
The lower legs
What is the biggest risk factor for PAD?
Smoking
What is the difference between thrombosis and embolisms?
A thrombosis is when a clot formed in the vessel obstructs that vessel
An embolus is when a clot is formed that travels to obstruct a vessel elsewhere- clots form on atherosclerotic plaques
What do muscle cells release in ischaemia that causes pain to be felt?
Adenosine
What is meant by critical ischaemia in PAD?
Critical ischaemia occurs when pain is felt at rest, often during the night time and patients describe having to hang their legs over the side of the bed to reduce the pain
Why might people with significant PAD be asymptomatic at rest?
Due to the recruitment of collateral vessels that provide alternative routes of blood flow meaning ischaemia is not experienced
Where would pain be felt in PAD affecting the lower aorta/iliac arteries?
Hips or buttocks
Where would pain be felt in PAD affecting the iliac or common femoral?
Thigh
Where would pain be felt in PAD affecting the superficial femoral artery?
Upper 2/3 of the calf
Where would pain be felt in PAD affecting the popliteal artery?
Lower 1/3
Where would pain be felt in PAD affecting the tibial or peroneal artery?
Foot
Describe the blood supply to the lower limb?
Abdominal Aorta
Common Iliac
External Iliac—> Common Femoral Artery
Internal Iliac —> Pelvic blood vessels
Common Femoral Artery
Gives of Profunda Femoris (Supply to Thigh)
Continues as Superficial Femoral (travels through adductor canal)
Enters popliteal artery when entering the popliteal fossa
Divides into anterior and posterior tibial arteries
Posterior tibial descends and gives of peroneal/fibular artery (supplies lateral compartment of leg).
Posterior tibial passes posteriorly to the medial malleolus and then becomes the lateral and medial plantar arteries
Anterior tibial descends down and at the foot becomes the dorsalis pedis artery
Note- Dorsalis pedis gives off deep plantar artery which anastomoses with the lateral plantar artery to form the deep plantar arch
https://www.youtube.com/watch?v=JNczJx2ju3I
When does the internal iliac become the common femoral?
When it crosses the inguinal ligament
Where can the femoral artery be palpated?
At the mid inguinal point- halfway between the asis and the pubic symphysis
Note- midpoint of the inguinal ligament is the location of the deep ring- this is halfway between the pubic tubercle and the ASIS
Describe the ulcers seen in PAD?
Painful
Sharp punched out lesions
Often over pressure points
Note- Neuropathic ulcers can also have a punched out appearance but sensation will be reduced whereas arterial ulcers are painful
What are some of the risk factors for PAD?
As for atherosclerotic disease
Smoking HTN Diabetes Hyperlipidaemia Age Male Gender Family History
What are some signs of PAD?
Absent foot pulses Hair loss Arterial ulcers- sharp boundaries and punched out appearance Bruit heard in the diseases artery Cold and pale legs Atrophic skin Buerger's angle <20 degrees Decreased CRT in the toes
What is buerger’s angle?
Angle at which the leg goes pale when raised up off the bed
What investigations should be done for PAD?
ABPI
Duplex- Ultrasound with a picture generated
CT/MR Angiogram
Describe the values for ABPI that indicate PAD is present?
Normal is 1-1.2
PAD= 0.5-0.9
Critical limb ischaemia <0.5 or ankle systolic <50 mmHg
What would cause falsely high values for ABPI?
Atheroscelrotic vessels- the calcification process makes them difficult to compress meaning that artificially high pressures are needed to compress them (this is greater than the actual systolic pressure)
