Limb ischemia is a severe blockage in the arteries of the lower extremities, which significantly reduces blood flow. Acute limb ischemia is a sudden and rapid decrease in lower limb blood flow.
There are three main stages of acute limb ischemia:
- Stage 1: Viable
- Limb is not immediately threatened
- No sensory loss
- No muscle weakness
- Doppler signals of arteries and veins are audible
- Stage 2: Threatened
- Stage 2a: Marginally threatened
- Limb is salvageable if promptly treated
- Minimal sensory loss (toes) or no sensory loss
- No muscle weakness
- Doppler signals of arteries are often inaudible; veins are audible
- Stage 2b: Immediately threatened
- Limb is salvageable with immediate revascularization
- Sensory loss is more than toes, associated with rest pain
- Mild to moderate muscle weakness
- Doppler signals of arteries are usually inaudible; veins are audible
- Stage 2a: Marginally threatened
- Stage 3: Irreversible
- Limb has major tissue loss or permanent nerve damage inevitable
- Profound sensory loss, numbness
- Profound weakness, paralysis
- Doppler signals of arteries and veins are inaudible
What Are Symptoms of Acute Limb Ischemia?
Symptoms of acute limb ischemia are often referred to as the “six Ps” and include:
- Pain that is located in the extremity and gradually increases in severity, but may eventually decrease due to progressive ischemic sensory loss
- Pallor: pale or mottled skin
- Poikilothermia: cool skin
- Pulselessness: diminished or absent pulse
- Paresthesia: numbness and tingling
- Paralysis
What Causes Acute Limb Ischemia?
Causes of acute limb ischemia include:
- Blockage in a blood vessel (embolism) by such as by a blood clot, a fat globule, a bubble of air or other gas, or foreign material
- Blood clot (thrombosis)
- Peripheral artery disease due to atherosclerosis
- Tear in the lining of an aortic or peripheral artery (dissection)
- Major trauma
- Conditions that cause vasospasm
- Raynaud phenomenon
- Shock (e.g., meningococcal sepsis, cardiogenic shock)
- Administration of vasoactive drugs
How Is Acute Limb Ischemia Diagnosed?
Acute limb ischemia diagnosed with a patient history and physical examination. The blockages associated with limb ischemia are located using one or more of the following methods:
- Auscultation
- Ankle-brachial index (ABI)
- Doppler ultrasound
- Computerized tomography (CT) angiography
- Magnetic resonance angiography (MR angiography)
- Angiogram
What Is the Treatment for Acute Limb Ischemia?
Immediate treatment is needed for limb ischemia to re-establish blood flow to the affected area and to preserve the limb.
Treatments for acute limb ischemia include:
Reviewed on 11/19/2021
References
Image Source: iStock Images
https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H403210236
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326052/
https://www.uptodate.com/contents/clinical-features-and-diagnosis-of-acute-lower-extremity-ischemia#H403210236
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6326052/