Peripheral Arterial and Venous Disease Flashcards
What is the role of the deep fascia in the leg?
The deep fascia surounds the calf muscle. This means that when the muscles contract, the pressure rises which allows venous flow to go up.
What are the key deep veins in the leg?
- External iliac vein
- Femoral vein
- Popliteal vein
What are the key superficial veins in the leg?
Long saphenous vein (drains into femoral triangle)
Short saphenous vein (drains into popliteal fossa)
Where is the long saphenous vein?
This is the one constant vein.
ALWAYS infront of the medial malleolus.
It is important as can use it to get fluid into venous system.
What are the roles of valves?
Prevent backflow.
How is venous blood returned to heart?
Blood flows from superficial to deep.
Deep via calf muscle pump pushes blood back to the heart
What are varicose veins?
Varicose veins are tortuous, twisted or lengthened veins.
Where are common sites of varicose veins?
Long saphenous
Short saphenous
What causes varicose veins?
The vein wall is inherently weak in varicose veins,
which leads to dilatation and separation of valve
cusps**so that they become**incompetent
What are the symptoms of varicose veins?
- Heaviness
- Tenson
- Aching
- Itching
Only attribute it if along the vein itself.
What are the complications if a patient has venous hypertension in the lower limb?
From the vein itself
- Haemorrhage
- Thrombophlebitis
From venous hypertension
- Oedema
- Skin pigmentation
- Varicose eczema
- Lipodermatosclerosis
- Venous ulceration
How do you stop bleeding from varicose veins?
Lie the patient down and elivate the leg.
(Bleeding from varicose veins usually occurs in the shows as the patient is standing (gravity) and hot (venodilation)
What is thrombophlebitis?
Low blood velosity which results in thrombosis.
Venous thrombosis produces an inflammatory response, including PAIN (bad pain)
What is haemosiderin staining?
Oxidising iron in blood from ferrous to ferric.
So, see rust under the skin.
Varicose eczema
- Lower limb
- Very itchy
What is Lipodermatosclerosis?
Thickening of the fat in the skin,
Can lead to venous ulceration
Venous ulceration
It is venous hypertension that leads to venous ulceration.
Venous hypertension is a result of calf muscle pump failure.
What are the causes of calf muscle pump failure?
- ‘Failure; of calf muscle contraction - immobility, obesity, reduced hip, knee and/or ankle movement
- Deep vein incompetence
- Volume overload - superficial vein incompetence (as blood goes through the valve the wrong way and into calf muscle pump. So, overfilling of calf muscle pump)
What is Virchow’s triad?
Thrombosis occurs when there is:
- Changes in the lining of the vessel wall
- Changes in the flow of blood
- Changes in the constituents of blood
What is the most common cause of arterial thrombosis?
Changing in the lining of the vessel wall
What is the most common cause of venous thrombosis?
Changes in blood flow - Stasis leads to venous thrombosis
Why does stasis lead to venous thrombosis?
In reality it is usually stasis plus another ‘provocateur’ – surgery
(trauma), oral contraceptive pill, dehydration, cancer.
Arterial thrombosis in response to bleeding involves platelets, extrinsic and then intrinsic pathways. Arterial thrombi are platelet rich
Venous bleeding
Venous thrombosis does not involve platelets in
a major way, initially the intrinsic pathway is
involved and then the extrinsic. Venous thrombi
are fibrin rich.
Low flow initiates Venous thrombosis
What does DVT produce?
Most commonly begins in the deep calf veins.
Produced an inflammatory response.
- Calor
- Dolor
- Functio laesa
- Rubor
- Tumor
What are the clinical features (signs and symptoms) of a DVT?
Symptoms
- Pain, cannot walk
- Swelling
- Blue-red skin discolouration
Signs
- Calf tenderness
- Muscle induration
- Skin warmth
- Skin discolouration
- Distended, warm superficial veins
- Oedema
- Pyrexia
Why is there an association between surgery and DVT?
- Immobility prior to surgery
- No calf muscle pump during surgery
- Immobility after surgery
- Surgery is trauma. The body’s response trauma includes a ‘prothrombotic state’
The dreaded, often fatal consequence of DVT is pulmonary embolism.
Where in the body is collateral circulation common?
Particularly common across joints
- Elbow
- Knee
- Shoulder
- Hip
- ect…
When does collateral circulation develop?
Collateral circulation develops in response to a stenosis.
This can take weeks or months but, it means if the vessel gets blocked, the patient may not notice anything.
How does acute limb ischaemia occur?
- The limb goes from a normal blood supply to greatly impaired blood supply over a period of minutes. No chance for for collateral vessel development (takes weeks / months)
- Commonest cause are embolism (from heart or abdominal aortic aneurysm) and trauma
- Sudden onset
- If not reversed within 6 hours the limb cannot be recovered and if not amputated the patient will die (hyperkalaemia due to dead tissue releasing intracellular potassium)
What are the signs / symptoms of acute ischaemia?
6 P’s
- Pain
- Paralysis
- Paraesthesia
- Pallor
- Perishingly cold
- Pulseless
What is the colour of a leg in acute peripheral ischaemia?
- White
- Blue
- Fixed mottled
What are the types of peripheral arterial disease?
- Intermittent claudication (equivalent to stable angina)
- Critical ischaemia
- Rest pain (equivalent to unstable angina)
- Ulceration/gangrene (equivalent to myocardial infarction)
What is the definition of claudication?
Pain in the muscles of the lower limb excited by walking / exercise.
The calf muscle are most frequently affected, although more proximal muscles may be affected.
Pain relieved rapidly by stopping exercise for a few mitures even whilst standing up.
What are the relevent arterials in leg?
Aortoiliac occlusion
- Bilateral buttock, thigh and calf claudication
- Absent lower limb pulses
- Rare
Common Illiac occlusion
- Right buttock, thigh and calf claudication
- Absent right lower limb pulses
- Not so common
Common femoral (or external iliac) occlusion)
- Right thigh and calf claudication
- Absent right lower limb pulses
- Not so common
Suoerficial femoral artery occlusion
MOST COMMON
- Right calf claudication
- Femoral pulse present, absent popliteal and pedal pulss
- By far the most common finding in patients with claudication
Critical ischaemia
Limb viabiltiy is threatened
- Rest pain (Equivalent to unstable angina)
- Ulceration / gangrene (Equivalent to MI)
What is rest pain?
- Pain in the FOOT that comes on when the patient goes to bed and is relieved by hanging the foot out of the bed
- The ischaemia is so severe that at rest the foot skin, muscles, bones are ischaemic at rest. This means that there is not enough oxygen to provide for the cells basic metabolic requirements.
- If left untreated will lead to:
- Dry gangrene (mummification)
- Wet gangrene
- Ulceration
Can save the leg in 95% of patients that present with rest pain.
