Vascular Flashcards
Define acute limb ischaemia
a sudden decrease in arterial perfusion in a limb which threatens the viability of the limbs
Define Chronic limb ischaemia
Peripheral arterial disease resulting in a symptomatic reduced blood supply to the limbs
Intermittent claudication –> critical limb ischaemia
Causes of acute limb ischaemia?
Thrombus
Emboli - AF, post-MI mural thrombus, abdominal aortic aneurysm, or prosthetic heart valves
Trauma - also compartment syndrome
Causes of chronic limb ischaemia?
Atherosclerosis
Vasculitis
RFs for chronic limb ischaemia?
Smoking Diabetes mellitus Hypertension Hyperlipidaemia Increasing age Family history Obesity and physical inactivity Renal failure
6 Ps of acute limb ichaemia in order of when they usually occur?
Pain
Pallor
Pulselessness
Perishingly cold
Paraesthesia - indication for immediate revascularisation
Paralysis - indication for immediate revascularisation
Explain the Rutherford classification of acute limb ischaemia
I: Viable, No immediate threat, No sensory or motor loss, audible arterial and venous doppler
IIA: Marginally threatened, salvageable if prompt tx, minimal sensory loss, no motor deficit, inaudible arterial and audible venous doppler
IIB: Immediately threatened, salvageable if immediate revascularisation, sensory loss in toes or more with rest pain, mild/moderate motor deficit, inaudible arterial and audible venous doppler
III: Irreversible, major tissue loss + permanent damage, profound sensory loss, profound paralysis, inaudible arterial and inaudible venous doppler
Explain the Fontaine classification of chronic limb ischaemia
Stage 1: Asymptomatic
Stage 2: Intermittent claudication
Stage 3: Ischaemic rest pain
Stage 4: Ulceration/gangrene
Where is the disease in calf claudication?
Superficial femoral artery
Where is the disease in buttock claudication?
Iliac artery
Define critical limb ischaemia (3 points)
Ischaemic rest pain for >2 weeks
Ulcers or gangrene
ABPI <0.5 or ankle pressure <40mmHg
Leriche Syndrome pathophysiology and triad of symptoms?
aortoiliac occlusive disease
buttock claudication
erectile dysfunction
absent/weak distal pulses
What Buerger’s angle indicates severe ischaemia
<20 degrees
What bloods to do in acute limb ischaemia?
FBC Serum lactate: to assess level of ischaemia Thrombophilia screen Clotting profile Group and save
Gold standard ix for chronic limb ischaemia?
MRI/CT angiogram
Acute limb ischaemia Mx?
Surgical emergency (Rutherford IIB)
o High-flow oxygen
o Gain IV access
o Initiate heparin
If embolic cause, options are:
• Embolectomy via a Fogarty catheter
• Local intra-arterial thrombolysis
• Bypass surgery, if there is insufficient flow back
If thrombotic cause, options are:
• Local intra-arterial thrombolysis
• Angioplasty
• Bypass surgery
If irreversible - amputation
Long term mx of acute limb ischaemia?
Reduce cardiovascular mortality risk
Lifestyle: regular exercise, smoking cessation, weight loss
Anti-platelet agent: low-dose aspirin or clopidogrel
Chronic limb ischaemia mx?
Lifestyle: smoking cessation, regular exercise (programme), weight loss
Statin therapy: atorvastatin 80mg OD
Anti-platelet: clopidogrel 75mg OD
Optimise diabetes control
Praxilene: if not fit for surgery
Surgery: angioplasty +/- stenting or bypass graft
Complications of acute limb ischaemia tx?
Reperfusion injury - can cause compartment syndrome and AKI
Complications of chronic limb ischaemia?
Sepsis secondary to infected gangrene
Acute-on-chronic ischaemia
Amputation
Characteristics of venous eczema?
Itchy red, blistered and crusted plaques; or dry fissured and scaly plaques on one or both lower legs (commonly mistaken for cellulitis).
Atrophie blanche: star-shaped ivory-white depressed atrophic plaques with red dots within the scar (dilated capillaries) and surrounding hyperpigmentation (due to haemosiderin deposition)
Orange-brown patches of pigmentation caused by haemosiderin deposition
Lipodermatosclerosis
Characteristics of Lipodermatosclerosis?
Skin hardening (often referred to as induration) Hyperpigmentation Erythema Swelling Inverted champagne bottle appearance
Characteristics of venous ulcers?
Large, irregular border with sloping edges
Shallow depth
Often located over the medial aspect of the ankle (referred to as the gaiter region).
Associated with mild pain
Characteristics of arterial ulcers?
Small, clearly defined border, irregular edge
Dry necrotic base
Deep
Often in between toes/dorsum of feet over bony prominences
Painful
How does a saphena varix present?
Lump 2-4cm inferior-lateral to the pubic tubercle
Blue tinge
Soft to palpate
Vanishes on lying down (differentiates from inguinal hernia)
RFs for varicose veins?
Prolonged standing Obesity Pregnancy Family history Valve damage: post DVT High flow: AV fistula Venous outflow obstruction: DVT, pelvic masses (pregnancy), ascites, lymphadenopathy
Where do the great and lesser saphenous veins run?
Great saphenous vein: medial side of leg
Lesser saphenous vein: lateral side of lower leg