Chronic Arterial Insufficiency

Question 1

Assessment of vascular system

Answer 1

• Golden 5 - consent, chaperone, privacy, exposure, confidentiality
• Observations - calculate NEWS score
• Radial pulse - peripheral pulse, rate rhythm, volume, character, delay + capillary refill
• Carotid pulse - central pulse, not at same time, check peripheral and central at same time
• CVS exam - listen to heart sounds
• Lower limbs - inspection (standing) and palpation
• Inspect - hair changes, swelling, assymetry, skin changes
• Palpation - examine normal side first
• Pulses - distal to proximal (dorsalis pedis first)

Question 2

What happens in CAI?

Answer 2

• Collateral vessels form
• Allow blood supply to go past blockage
• Body does not have time to do this in acute cases

Question 3

What is AI?

Answer 3

• Anything that hinders blood flow in arteries
• More common in men than women
• Increased prevalace with age
• Presents with intermittent claudication usually
• Atherosclerosis common cause

Question 4

Composition of arteries vessels

Answer 4

• Tunica adventitia
• Tunica media
• Tunica intima (inside) - this is what atherosclerosis affects

Large plaques can affect nutrition to tunica media from tunica intima = apoptosis = damage to wall = aneurysms

Question 5

Lower limb vasculature

Answer 5

• L4 = level of common iliac
• Then external and internal iliac
• As external iliac crosses inguinal ligament = femoral artery
• Femoral triangle
• Profunda femoris and superficial femoral artery branch
• Knee - superficial artery –> Popliteal artery
• –> anterior and posterior tibial artery (posterior) and peroneal artery (lateral)

Question 6

Arteriosclerosis

Answer 6

• Hardening of arteries due to thickening of BV wall, medium and large arteries
• Can be split into atherosclerosis (intima), arteriolosclerosis (small arteries hyaline) Monkeberg medial calcific sclerosis (calcium in media)

Question 7

What is atherosclerosis and atheromatous plaques

Answer 7

• Hardening of arteries due to intimal atheromatous plaque
• Has necrotic lipid core (cholesterol) with fibromuscular cap - can rupture
• Damage endothelium = lipid moves into intima
• Lipids oxidised and consumed by macrophages = foam cells
• = inflammation, SM proliferation, deposition of ECM
• = turbulant blood flow

Question 8

Consequence of turbulant blood flow in arteries

Answer 8

• Arterial thrombus
• As can cause endothelial injury and stasis of blood

Question 9

RF for CAI

Answer 9

Same as CVS
* Age
* Smoking
* Hypertension
* Smoking etc etc

Question 10

Classification of PAD

Answer 10

• Fontaine classification

Question 11

Fontaine classification

Answer 11

1 - Asymptomatic
2 - intermittent claudication (2a is more than 200m, 2b is within 200m)
3 - rest pain
4 - ulceration, gangrene or both

Question 12

What is intermittent claudication?

Answer 12

• Cramp like pain felt in muscles
• Commonest site = calf
• As superficial femoral artery most commonly affected
• Brought on by walking, relieved by standing still (unlike neuropathy) not present on first step (like OA)

Question 13

Classifcation of IC

Answer 13

• Boyds Classification
• I-IV

Question 14

Claudication distance?

Answer 14

• Relative - Distance a person can walk before the onset of pain
• Absolute - distance person can walk before they cannot walk anymore

Question 15

What is rest pain?

Answer 15

• Pain in limb at rest
• Classically at night time - felt in foot most common
• Exacerbated by lying down/elevating foot
• May improve by hanging foot out of bed
• Due to involvement of vasa nervorum (nerves in tunica adventitia)
• Pressure of enviroment on foot makes it worse - even touching can hurt with duvet

Question 16

Management of rest pain

Answer 16

• Analgesia - need to help sleep

Question 17

What is critial stenosis / critical limb ischaemia?

Answer 17

• Critical stenosis is occlusion of greater than 70%
• Imminent threat to limb
• Can cause tissue loss

Question 18

Tissue loss in PAD

Answer 18

• Ulceration or gangrene
• Gangrene can be wet or dry
• Divide foot into forefoot, midfoot and hindfoot
• Zone of demarcation - clear between devitalised and healthy tissue?
• Sometimes associated erythema

Question 19

Wet vs dry gangrene

Answer 19

• Wet has additional infection on top of necrosis

Question 20

Types of gangrene

Answer 20

1. Dry
2. Wet
3. Gas - clostridium perfringens

Question 21

Investigations for gangrene

Answer 21

• X-ray to check for osteomyelitis

Question 22

Management PAD 4 meds and lifestyle

Answer 22

• DATES - Diet, alcohol, tabacco, exercise, stress
• Antiplatelets (Clopidogrel, if not aspirin)
• Statins (high intensity)
• PPI? - Lansoprazole if high risk
• Naftidrofuryl oxalate (5-HT2 receptor antagonist that acts as a peripheral vasodilator)

Question 23

Antiplatelets for PAD

Answer 23

• Aspirin - COX (cyclooxygenase) inhibitor, prevents formation of thromboxane from arachidonic acid
• Clopidogrel - binds to ADP and inhibits

Question 24

MOA of statins

Answer 24

• Inhibit HMG Co-A reductase
• = decreased liver cholesterol increased LDL receptor expression

Question 25

What NOT to give someone with PAD in hospital and why?

Answer 25

* TED stockings - thromboembolic deterrent stockings * Further impede blood flow in arteries that are already compromised * Use LMWH if need instead

Question 26

Investigation for PAD - of choice

Answer 26

* Often clinical, can use ABPI too * USS doppler * CT angiogram if needed before surgery sometimes or if higher up as bowel gas can get in way of USS - contrast needed

Question 27

Things to check before CT with contrast

Answer 27

* Allergies * Kidney function * Pregnancy

Question 28

Surgical options for PAD

Answer 28

* Angioplasty * Bypass * Amputation if not suitable for revascularisation

Question 29

Whats angioplasty?

Answer 29

* Minimally invasive * Through groin vessel usually * Go in with catheter * Inflate balloon and can leave stent in place if needed * Sometimes have antiplatelet drugs on stent?

Question 30

What is bypass?

Answer 30

* Use graft to bypass blockage in artery * Bypass sometimes needed if vessel is too narrow for angioplasty * Can use long saphenous vein for this or omniflow (biosynthetic graft)

Question 31

How can veins be used for arterial replacement in bypass?

Answer 31

* Remove valve function - reverse * Need at least 3mm calibre to be suitable * Assess intraoperatively to check for leaks * Superficial vein used - long saphenous vein, allows deep system to take over if it needs t

Question 32

Which vessels most least likely to be involved in PAD?

Answer 32

* Upper limb arteries eg Brachial artery is uncommon

Question 33

What symptoms are associated with PAD?

Answer 33

* Intermittent claudication * Rest pain * Dry or wet gangrene * Sexual dysfunction * Cold peripheries

Question 34

BMT for PAD

Answer 34

* Antiplatelets (NOT anticoags) * Statins * PPIs * + DATEs

Question 35

Test for PAD severe ischaemia

Answer 35

* Buergers test * Patient lie supine and raise legs until they go pale * Lower them until colour returns * Angle at which limbs go pale = Buergers angle * Less 20 degrees = severe ischaemia

Question 36

What is Leriche syndrome?

Answer 36

* Type of PAD affecting aortic bifurcation Presents with: * Buttock pai or thigh pain * Erectile dysfunction

Question 37

How can critical limb threatening ischaemia be defined?

Answer 37

* Ischaemic rest pain greater than 2 weeks * Presence of ischaemic legions/gangrene * ABPI less than 0.5 Can see gangrene, hair loss and thickened nails on exam

Question 38

Differentials for claudication presentation

Answer 38

* Spinal stenosis - symptoms relieved by sitting rather than standing still * Acute limb ischaemia - present within hours, less than 14 days duration of symptoms

Question 39

ABPI and severity of PAD

Answer 39