Acute limb ischaemia occurs when there is blockage of a peripheral artery, either from a thromboembolism, or sometimes from an embolic plaque. It frequently occurs on a background of peripheral vascular disease.
- Thrombus in situ – 40%
- Emboli – 38%
- Angioplasty occlusion – 15%
- Compartment syndrome – rare
Signs and Symptoms
- Pain – muscles also become tender to palpation after about 6-8hours
- Perishing cold
- Fixed mottling of the skin implies irreversibility
- BEWARE – hot red leg may sometimes be present, which can result in misdiagnosis of gout or cellulitis
- It is an EMERGENCY!
- 22% of cases are fatal
- 16% of cases result in amputation
- Thrombolytic agent e.g. tissue plasminogen activator (tPA)– most effective when given via local arterial catheter (Fogarty Catheter), particularly for occlusions <2 weeks. Therapy is usually given via the catheter for 8-24hr
- Open surgery / angioplasty – DON’T BE AFRAID TO DO THESE! – equally, don’t be afraid to do angiography in cases of an unsure diagnosis.
- The decision to opt for thrombolysis over surgery depends on risk assessment on an individual patient basis (i.e. risks of surgery vs risks of thrombolysis)
- You should use heparin anticoagulation after both surgery and thrombolysis!
- Look for a source of emboli – e.g. ultrasounds of aorta, popliteal and femoral arteries for signs of aneurysm
- Watch out for reperfusion injury – which can lead to compartment syndrome
- 92 year old nursing home patient
- Painful left leg, sudden onset
- Deaf and dementia
- Comfortable after 5mg morphine (relatively small dose)
- BP 110/40 – probably slightly low
- HR 80 irregular
- RR 16
- Heart sounds normal
- Whole left leg is white and cold
- Some mottling from foot to just above knee
- Calf is very tender
- Can barely move right leg, but can wiggle toes. Cannot move left leg at all.
- Pulses on the right are normal.
- No palpable aortic aneurysm
- No obvious swelling of the leg