Acute limb ischaemia

Question 1

You are asked to review a 74-year-old man on the vascular surgical ward. He underwent a right femoral artery angioplasty four hours earlier. He is complaining of severe right foot pain. his pulse rate is 80/min and regular. The right foot is pale and cold, There are no palpable pedal pulses below the groin pulse. There is no paralysis and no paraesthesia of the lower leg. What is the appropriate management?

Answer 1

Impression
salient features of this stem include the cold, pale, painful R foot following vascular surgery four hours earlier. This is concerning for acute lower limb ischaemia, and constitutes a surgical emergency demanding immediate assessment and management. Presently, the limb remains salvageable with reperfusion surgery. Sounds like Rutherford 2B classification of acute limb ischaemia.

This is most likely due to thrombus formation at this site of angioplasty, however could be due to a number of other causes;
- stent thrombosis
- arterial dissection, perforation, aneurysm
- compartment syndrome
- cardiac arrhythmia + thromboembolus
- reperfusion injury

Rule out DVT/PE, ACS.

Question 2

Acute limb ischaemia - initial assessment/management

Answer 2

Initial assessment/management
- escalate care to vascular reg
- keep patient NBM
- pre-operative bloods if appropriate: FBC, coags, G+H, UEC (contrast during surgery)
- initial assessment utilising A to E approach, rule out life-threatening differentials and initiate any temporising measures

Question 3

Acute limb ischaemia - History

Answer 3

History
Read surgical report, other EMR notes to get idea of surgery that was performed, and any pre-operative investigations.

• sx: time (critical time period for repercussion is 6 hrs), 6 P’s of acute limb ischaemia,
• Screen life-threatening: chest pain, dyspnoea, calf pain, haemoptysis, etc
• HPC: chronic limb ischaemia, PVD, CVD, claudication
• RISK: hyperlipidaemia, smoking, alcohol, diabetes, obesity,
• PMHx, PSHx
• Medications: current anti platelet and anticoagulation
• Functional status

Question 4

Acute limb ischaemia - Examination

Answer 4

Examination
- general appearance + vital signs
- Peripheral vascular examination: temperature, cap refill, HR, BP, pulses, abdomen. Buerger’s test.
- Cardiovascular and neurological examination

Question 5

Acute limb ischaemia - Investigations

Answer 5

Investigations
- Diagnostic: Duplex LL US, CT angiography, DSA
- Bedside: handheld doppler US for pulses, Ankle brachial index - calculate Rutherford Classification for acute limb ischaemia (1, 2a, 2b, 3), ECG for cardiac DDx.
- Bloods: Pre-op: FBC, coags, G+H, UEC. cardiac profile for chronic disease management/optimisation (LFT, lipid panel, HbA1C, etc)

Question 6

Acute limb ischaemia - Management

Answer 6

Management
- immediate involvement of vascular surgery team.

Definitive:
- immediate heparin infusion with regular assessment and aPTT monitoring
- surgical management is mandatory for Rutherford 2B; embolectomy/thrombectomy [with fogarty’s catheter], revascularisation surgery +/1 amputation if limb no longer viable.
- Angioplasty: ballooning, stenting, bypass, amputation

Supportive
- analgesia, anti-emetics
- fluids
- o2 supplementation
- NBM for theatres

Ongoing
- optimise cardiovascular risk factors with lifestyle and pharmacological interventions