11. Peripheral arterial and venous disease

Question 1

what is the relationship between superficial and deep peripheral veins

Answer 1

superficial veins (within subcutaneous tissue) drain into deep veins (within muscle) via perforating veins which pierce deep fascia

Question 2

what is the one constant vein in the body

Answer 2

the long saphenous vein anterior to the medial malleolus

Question 3

how is blood in peripheral venous system moved against gravity to heart

Answer 3

1. muscular contractions within tight deep fascial compartment compress veins - i.e. calf pump
2. valves to prevent back flow

Question 4

what is the pathophysiology behind varicose veins

Answer 4

vein wall weakness… vein dilation and separation of valve cusps… valves become incompetent.

Question 5

what are the symptoms of varicose veins

Answer 5

• heaviness and tension
• aching
• itching (histamine release)
  Along the vein itself

Question 6

what are the possible direct and indirect complications of varicose veins

Answer 6

Direct from vein itself:

• haemorrhage
• thrombophlebitis

Indirect due to venous hypertension:

• peripheral oedema
• venous ulceration
• skin pigmentation
• varicose eczema
• lipodermatosclerosis (hardening of fat)

Question 7

what is thrombophlebitis

Answer 7

inflammatory process causing blood clot formation and obstruction of a vein - can be superficial or deep, i.e. deep vein thrombosis

Question 8

explain the causes of venous hypertension

Answer 8

Is a result of calf muscle pump failure, itself due to:

1. failure of calf muscle contraction - immobility, obesity, reduced hip, knee or ankle movement
2. deep vein incompetence (congenital)
3. volume overload - superficial vein incompetence (causes increased blood flow into calf muscle pump via perforating veins rather than blood entering deep veins higher up)

Question 9

name the 3 components of Virchow’s triad. which is most important in venous thrombosis or in arterial thrombosis

Answer 9

1. hypercoagulability
2. change in blood flow, i.e. stasis - most important in venous thrombosis
3. change in vessel lining, i.e. blood vessel damage - most important in arterial thrombosis

Question 10

where does DVT most commonly develop

Answer 10

deep calf veins

Question 11

what are the signs and symptoms of DVT

Answer 11

symptoms (not always present!):

i. pain (can’t walk)
ii. swelling

signs:

i. calf tenderness
ii. muscle induration
iii. blue-red skin discoloration, warmth, distended superficial veins
iv. oedema
v. pyrexia

Question 12

what is acute limb ischaemia and when does it become irreversible

Answer 12

• Sudden onset obstruction of blood supply to a limb - no chance for collateral vessel development (takes weeks/months).
• If not reversed within 6 hrs, limb cannot be recovered and if not amputated, P will die.

Question 13

why can a P die of acute limb ischaemia

Answer 13

hyperkalaemia due to intracellular K+ release from necrotic tissue

Question 14

what are the symptoms/signs of acute ischaemia

Answer 14

1. pain
2. paralysis
3. paraesthesia
4. pallor
5. perishing cold
6. pulselessness

Question 15

what are the colour changes in an acutely ischaemic limb

Answer 15

1. white initially

2. fixed mottling (doesn’t blanch when pressed) due to patchy cyanosis from lack of O2

Question 16

what is intermittent claudication

Answer 16

pain in muscles of lower limb elicited by walking/exercise (calf muscles most frequently affected as commonly involves superficial femoral artery supplying calf) and rapidly relieved by rest

Question 17

what are the important pulses to feel in the lower limb and where are these found

Answer 17

1. femoral pulse - mid-inguinal point
2. dorsalis pedis pulse - lateral to extensor hallucis longus
3. posterior tibial pulse - behind medial malleolus

Question 18

what are the signs/symptoms of critical chronic limb ischaemia

Answer 18

1. rest pain: pain in the foot occuring when P goes to bed (no gravity, warmer so increased metabolic activity) and relieved by hanging foot out of bed
2. ulceration/gangrene