Acute Limb Ischaemia Flashcards
Clinical 6P’s presentation of PAD
Pain
Pallor
Pulselessness
Paresthesia (pins and needles)
Perishingly cold
Paralysis
Define Ankle-Brachial Pressure Index
the ratio of systolic blood pressure (SBP) in the ankle compared with the systolic blood pressure in the arm
ABPI normal range
1.0 – 1.4
ABPI borderline range
0.9 – 0.99: possible peripheral arterial disease
ABPI abnormal range
< 0.9: suggests peripheral arterial disease
ABPI non-compressible range
- > 1.4
Percutaneous transluminal angioplasty indication
- Thrombotic cause
- Rutherford 2B
Define acute limb ischaemia
the sudden decrease in limb perfusion that threatens the viability of the limb
3 main groups
Acute limb ischaemia causes
- Embolisation: a thrombus from a proximal source travels distally to occlude the artery (most common)
- Thrombosis in situ: an atheroma plaque in the artery ruptures
- Trauma: compartment syndrome
what is the most common cause of acute limb ischaemia
Embolisation - a thrombus from a proximal source travels distally to occlude the artery
Embolisation causes for acute limb ischaemia
- chronic limb ischaemia
- AF
- recent MI (resulting in a mural thrombus)
- AAA
- Peripheral aneurysm
Define limb viability
capacity to survive and function, encompassing both circulation and long-term functionality
Time frame for reversible acute limb ischaemia
within 6 hours
untreated acute limb ischaemia pathological changes
- Cellular oedema / necrosis
- Endothelial Damage
- Paralysis
Acute limb ischaemia surgical Mx
- Embolectomy via a Fogarty catheter; this can be done over a wire using radiological guidance
- ## Local intra-arterial thrombolysis
Acute limb ischaemia anticoagulant Mx
-
initial therapeutic dose or IV heparin
followed by - prolonged heparin course
acute limb ischaemia complications
Reperfusion injury, whereby the sudden increase in capillary permeability can result in:
- Compartment syndrome: following revascularisation
Substances from the damaged muscle cells
- K+ - hyperkalaemia
- H+ - Acidosis
- Myoglobin - AKI (renal tubular obstruction)
