From the Guidelines
Acute limb ischemia (ALI) is categorized into three main categories: Viable, Threatened, and Irreversible.
Categories of ALI
- Viable: The limb is not immediately threatened, with no sensory loss, no muscle weakness, and audible arterial and venous Doppler signals 1.
- Threatened: This category is further divided into two subcategories:
- IIa (Marginally Threatened): Mild-to-moderate sensory loss, no motor loss, inaudible arterial Doppler, and audible venous Doppler signals 1.
- IIb (Immediately Threatened): Sensory loss involving more than the toes, mild-to-moderate motor weakness, inaudible arterial Doppler, and audible venous Doppler signals 1.
- Irreversible: Major tissue loss or permanent nerve damage is inevitable, with profound sensory loss, profound muscle weakness or paralysis, and inaudible arterial and venous Doppler signals 1. These categories are based on the severity of symptoms, sensory and motor loss, and Doppler signal findings, and are crucial for guiding treatment and management of ALI 1.
From the Research
Categories of Acute Limb Ischemia (ALI)
The categories of acute limb ischemia (ALI) can be classified based on the Rutherford classification, which aids clinicians in selecting appropriate therapy 2, 3. The categories are:
- Threatened but viable limbs
- Irreversibly damaged limbs
Rutherford Classification for Acute Limb Ischemia
The Rutherford classification for ALI includes:
- Category IIa: marginally threatened limbs
- Category IIb: immediately threatened limbs These categories are used to determine the severity of ischemia and limb viability, and to guide treatment decisions 2, 3.
Importance of Classification
The classification of ALI is crucial in determining the appropriate treatment approach, as it helps to identify the severity of ischemia and the viability of the limb 4, 5. Prompt diagnosis and revascularization are essential in reducing the risk of limb loss and mortality 6.