19 - Peripheral Arterial and Venous Disease Flashcards
Label the following deep and superficial veins.
Circles are where perforators are
Where can you view the long saphenous vein?
- In front of the medial malleolus
- Can put emergency IV in here
What veins do the superficial veins drain into?
How does the calf muscle pump work?
- Soleus and gastrocnemius muscles push blood against gravity when they contract
- Valves open and blood pushed through deep veins
- Muscles relax and perforating valves open to allow filling of deep veins from superficial
Where are the superficial and deep veins located in the lower limb and how does blood travel between them?
What happens in varicose veins?
- Walls of the veins become weakened and thin, veins swell and valve cusps separate and become incompetent
- Veins becomes twisted, can be asymptomatic
If there are symptoms with varicose veins, what are they?
- Heaviness
- Aching
- Muscle cramps
- Throbbing
- Thin itchy skin along affected vein
What are some complications with varicose veins?
Complications due to venous hypertension
- Varicose eczema
- Skin pigmentation (haemosiderin)
- Lipodermatosclerosis (inflammation of fat layer under skin) - Venous ulceration
- Oedema
- Haemorrhage (after shower)
- Thrombophlebitis
- Pain
Why do you get hyper skin pigmentation with venous hypertension?
- Haemosiderin staining
- Leakage of RBC from venues and the Fe3+ and this gets oxidised causing staining
What is lipodermatosclerosis?
Inflammation of the fat layer under the skin of the lower limb. Linked with venous eczema and therefore venous hypertension
- Pain
- Hardening of the skin
- Redness
- Swelling
- Tapering of skin above ankles
Where does venous ulceration usually occur?
Around hard nodular areas, usually medial malleolus due to venous hypertension
(chronic, painful)
What causes the calf muscle pump to fail?
Disuse of calf muscles or not using them properly e.g immobility, obesity, weak plantarflexion
What happens if there is incompetence of a deep vein and what happens if this is in a superficial vein of the lower limb?
- Deep vein —> retrograde flow
- Superficial vein —> blood flow will reverse and go from deep vein to superficial vein so will overflow
How can you treat varicose and incompetent veins?
- Ligation and stripping
- Can help ulceration
What are the differences between thrombi in the arterial and venous system?
Arterial: most common cause is atheroma and they are platelet rich
Venous: most common cause is stasis and one other factor e.g pill, dehydration, pregnancy. Fibrin rich
What is the most common site of varicose veins?
Saphenous veins
What are some signs of a DVT and some differential diagnoses?
- Calf tenderness
- Warmth
- Distended and visible superficial veins
- Oedema
- Pyrexia with no other obvious cause
- Asymmetry
- Diagnoses: soft tissue trauma, cellulitis, lymph obstruction
What is economy class syndrome?
No calf muscle pump so blood stasis
How do you prevent DVT after surgery?
- Anticoagulant prophylaxis
- Promote mobility straight after surgery
DONE TO TRY AND AVOID PE
How do joints not go into acute ischaemia during bending of the joints?
- Collateral blood supply
- This can also develop in the coronary arteries when there is stenosis for example. Adaptive compensatory response
What is acute limb ischaemia and the signs of leg ischaemia?
Occlusion of blood supply occurs acutely so no time to develop collateral ligament. Usually due to AF or AAA forming a thrombus
If you suspect acute limb ischaemia what should you do?
Refer to vascular surgical unit immediately and extent of threat to limb willl guide treatment e.g imaging, angioplasty, thromboextomy, intra arterial thrombolysis, amputation
What is chronic peripheral arterial disease?
- Intermittent claudication of the lower or upper limb caused by atherosclerosis and ischaemia. It is exercise induced and pain goes away at rest
- When rest pain (e.g hanging foot out of bed at night to restore gravity) need to be referred immediately otherwise gangrene, ulceration or loss of limb
When you have peripheral arterial disease, what determines where the claudication is?
- Where the stenoses are present will show where claudication present and determine which pulse can be palpated
- Most common is atherosclerosis of superficial femoral artery that presents with calf claudication
Where can you palpate the following pulses?
- Femoral
- Popliteal
- Dorsalis pedis
- Posterior tibial
How can you look at blood flow and velocity in arteries and veins with no invasive techniques?
- Sonogram using ultrasounds and doppler effect
- Flow in veins blue and artery flow red
- Colour bar mapped to velocity and direction
- Red flow towards transducer, blue away
- Brightness of colour shows velocity
How does the doppler effect produce an image mathematically?
- Echoes from moving blood are detected and computed into direction of flow and velocity. Echoes from stationary tissues are the same so not converted
- Size of signal depends on blood velocity, ultrasound frequency and angle of insonation
How can you view a stenoses of a blood vessel using the Doppler effect?
- Increase in velocity at stenosis and turbulent flow following the occlusion
