Acutely Painful Limb

Question 1

What is the most common diagnosis of a cold and pale limb?

Answer 1

Acute limb ischemia

Question 2

What are the clinical features of acute limb ischemia?

Answer 2

Pain

Pallor

Pulselessness

Paresthesia

Perishingly cold

Paralysis

Question 3

Give examples of risk factors for acute limb ischemia

Answer 3

• Atrial fibrillation
• Hypertension
• Smoking
• Diabetes mellitus
• Recent myocardial infarction

Question 4

What are the causes of acute limb ischemia?

Answer 4

• Thrombosis in situ (40%)
• Emboli (38%)
• Graft and angioplasty occlusion (15%)
• Trauma

Question 5

How many hours does take before acute limb ischemia causes irreversible tissue damage?

Answer 5

4-6 hours to save the limb.

Question 6

How is acute limb ischemia diagnosed?

Answer 6

If acute limb ischaemia is suspected, a CT angiogram should be arranged if feasible for confirmation and anatomical delineation, along with an urgent vascular review.

Question 7

Briefly describe the treatment for acute limb ischemia

Answer 7

This is a medical emergency and may require open surgery or angioplasty.

If the occlusion is embolic, the options are surgical embolectomy (Fogarty catheter) or local thrombolysis, e.g. tissue plasminogen activator (t-PA), balancing the risk of surgery with haemorrhagic complications of thrombolysis.

Anticoagulate with heparin.

Question 8

What risks are associated with treating acute limb ischemia?

Answer 8

Post-operation reperfusion injury and subsequent compartment syndrome.

Question 9

What is the most common diagnosis of a hot and swollen limb?

Answer 9

Deep Vein Thrombosis (DVT)

Question 10

What are the clinical features of DVT?

Answer 10

• Calf warmth, tenderness, swelling and erythema
• Mild fever
• Pitting oedema may be present

Question 11

Briefly describe the Well’s Score

Answer 11

All 1 point:

• Active cancer (treatment within last six months or palliative)
• Calf swelling ≥3 cm compared to asymptomatic calf (measured 10 cm below tibial tuberosity)
• Collateral superficial veins (non-varicose)
• Pitting oedema (confined to symptomatic leg)
• Swelling of entire leg
• Localised tenderness along distribution of deep venous system
• Paralysis, paresis, or recent cast immobilisation of lower extremities
• Recently bedridden ≥3 days, or major surgery requiring regional or general anesthetic in the previous 12 weeks
• Peviously documented deep-vein thrombosis

Minus 2 points:

• Alternative diagnosis at least as likely as DVT

Question 12

Briefly describe the interpretation of the Well’s score

Answer 12

<1 point= DVT unlikely

• Perform D-dimer
• If negative, DVT is excluded
• If positive, proceed to ultrasound Doppler scan

>2 points= DVT likely

• Do D-dimer and ultrasound Doppler scan
• If both negative, DVT excluded
• If ultrasound Doppler positive, treat as DVT
• If D-dimer is positive and ultrasound Doppler is positive, repeat ultrasound Doppler in 1 week

Question 13

Briefly describe the treatment for DVT

Answer 13

If confirmed, they can be treated initially with therapeutic doses of Low-Molecular Weight Heparin (LMWH), before being swapped to a Direct Oral Anticoagulant (DOAC) if suitable, typically for 3-6 months. Those with an iliofemoral DVT with severe symptoms require urgent vascular review.

Question 14

Give examples of other causes that increase D-dimer

Answer 14

• Infection
• Pregnancy
• Malignancy
• Post-operative