Acute and Chronic Limb Ischaemia Flashcards
3 causes of Chronic Limb Ischaemia
Atherosclerosis
Vasculitis
Buerger’s disease
Risk factors for chronic limb ischaemia
Age Hypercholseterolaemia Hypertension Male Smoking Diabetes
Which classification system is used to stage symptoms of chronic limb ischaemia?
Fontaine classification
Describe the stages of the fontaine classification for chronic limb ischaemia
I - Asymptomatic, incomplete blood vessel obstruction
II- Mild claudication A)at distance greater than 200m B)distance less than 200m
III- Pain at rest, mostly in feet
IV- Necrosis and gangrene
What factors are included in history for diagnosis of chronic limb ischaemia?
Caludication - exercise tolerance, effect of incline, change over time, relief by rest, wsite, character, unilateral/bilateral
Rest pain - type, relieving factors
Tissue loss - duration, history of trauma, peripheral sensation
Risk factors - PMH, DH, SH, OH
Signs of chronic limb ischaemia
Ulceration
Pallor
Hair loss
What needs to be examined to diagnose chronic limb ischaemia?
Signs on inspection
Feel for capillary refill, temperature, pulses, peripheral sensation
Auscultate - Doppler - dorsalis pedis, posterior tibial
Special tests for chronic limb ischaemia
Ankle Brachial Index - ABPI
Buergers test
Explain conditions demonstrated by ABPI
Symptom free = ABPI of 1
Intermitent claudication = ABPI 0.5-0.95
Rest pain = ABPI 0.3-0.5
Gangrene and ulceration = ABPI less than 0.2
Explain Buerger’s test
Elevate legs
1)Pallor
2) less than 20 degrees -severe ischaemia
Hang feet over the edge of the bed - slow to regain colour - Hyperaemic sunset foot
Normally 1/3 of capillaries are opne- in CLI autoregulation lost –> all open
Management options for chronic limb ischaemia
Best Medical therapy
Severe - BMT, angioplasty/stent/surgical bypass
Critical -> Above plus endovascular reconstruction
Best Medical Therpay for Chronic limb ischaemia
Antiplatelets Statin BP control Smoking cessation Exercise Diabetic control
Investigations for chronic limb ischaemia
Duplex USS
CTA/MRA
Digital subtraction and angiogram
Surgical bypass complications
Bleeding Infection Pain Scar DVT PE MI CVA LRTI Death Damage to vein/nerve.artery Distal emboli Graft failure
Acute limb ischaemia occurs due to which 3 causes
Thrombus
Emboli
Trauma - compartment syndrome
What elements of history are illicited to diagnose Acute limb ischaemia?
History of chronic limb ischaemia Risk Factors Cardiac hisotry Onset Duration Function Social Hisotry - smoking, diet, exercise,
Presentation of Acute Limb Ischaemia
6 Ps Pallor Pain Paraesthesia Paralysis Pulseless Perishingly Cold
What syndrome can occur in Acute Limb Ischaemia?
Compartment syndrome Muscle ischaemia, inflammation, oedema, venous obstruction Tense tender calf Rise in creatinine kinase Risk of renal failure (myoglobulinaemia)
What are the features of compartment syndrome?
Muscle ischaemia, inflammation, oedema, venous obstruction
Tense tender calf
What risk is associated with compartment syndrome?
Rise in creatinine kinase
Risk of renal failure (myoglobulinaemia)
Management of Acute Limb Ischaemia
Bloods - ECG Nil by mouth Analgesia Anticoagulation
If limb is slavageable Embolectomy
Thrombosis in situ - mechanical thrombectomy/thrombolysis
Open embolectomy +/- bypass
What percentage of diabetic patients will develop foot ulcers?
15%
What needs to be investigated in diabetic foot disease?
Osteomyelitis
Gas gangrene
Necrotising fasciitis
Management of diabetic foot disease
Revascularisation
Amputation
Definition of acute limb ischaemia
Sudden decrease in perfusion of limb that threatens its viability
Causes of potential embolisation leading to acute limb ischaemia
CLI Atrial fibrillation MI Symptomatic AAA Peripheral aneurysms
Differentials for acute limb ischaemia
Critical chronic limb ischaemia
Acute DVT
Spinal cord or peripheral nerve compression
Investigations for acute limb ischaemia
Bloods - including lactate, thrombophilia screen, group and svae ECG Doppler US CT angiography CT arteriogram if limb salvageable
