Vascular- Acute Arterial Occlusion

Question 1

Etiology of Acute Arterial Occlusion

Answer 1

1. Embolization: From heart or proximal artery.
2. Trauma: Posterior knee dislocation, long-bone fracture, penetrating trauma.
3. Iatrogenic: Catheter-related.
4. Thrombosis: Atherosclerosis, aneurysm.

Question 2

Acute Arterial Insufficiency sign and symptoms

Answer 2

1. Pain: Earliest sign, often in peroneal nerve distribution.
2. Pulselessness: Absent distal pulses.
3. Pallor: Pale, ashen skin.
4. Paresthesia: Numbness/tingling.
5. Paralysis: Loss of motor function.
6. Poikilothermia: Cold limb.

Question 3

Most Important Signs of Acute Arterial Insufficiency

Answer 3

Paresthesia and paralysis are the most critical signs as nerves are highly sensitive to ischemia.

Question 4

Muscle Damage Progression

Answer 4

Soft -> Doughy -> Stiff/Hard. Irreversible ischemia when skin is mottled and no longer blanches.

Question 5

Differential Diagnosis of Acute Arterial Insufficiency

Answer 5

1. Nerve root compression.
2. Deep venous thrombosis (DVT).
3. Infection.

Question 6

Diagnosis of Acute Arterial Occlusion

Answer 6

If certain (cold, pulseless, painful extremity), no further workup needed.
ABI or angiography to confirm site.
On-table angiography in some centers.

Question 7

Embolism Source Identification

Answer 7

Identify the source of embolism and the reason (e.g., AFib, MI, valvular disease).

Question 8

Atheroembolism

Answer 8

Occurs from aorta, iliac, or femoral vessels to distal vessels.
‘Blue toe’ syndrome may occur.

Question 9

Thrombosis Etiology

Answer 9

Usually from atherosclerosis or hypercoagulable states. Effect varies with collateral circulation.

Question 10

Thrombosis Diagnosis

Answer 10

Angiogram required unless severe, rapidly progressing ischemia.
History of PVD or aneurysm may be present.

Question 11

Treatment Options for Acute Arterial Occlusion

Answer 11

1. Thrombectomy or grafting (most common).
2. Thrombolytic therapy (success rate 60-80%).

Question 12

Thrombolytic Agents

Answer 12

1. Streptokinase: Antigenic, bacterial origin.
2. Urokinase: From renal parenchyma (not available in the US).
3. tPA: From vascular endothelium.
4. Reteplase: Recombinant tPA.

Question 13

Thrombolytic Therapy Indications and Contraindications

Answer 13

Indications: Acute occlusion of native vessel or graft.
Contraindications: GI/cerebral lesion, pregnancy, angiography contraindications.

Question 14

Complications of Thrombolytic Therapy

Answer 14

Intracerebral or catheter site bleeding. May require surgical intervention.