Acute limb ischemia (ALI) occurs when there is a sudden lack of blood flow to a limb, typically an arm or leg. This can be due to a blood clot or a build-up of fatty deposits inside the arteries, causing them to narrow —like what occurs in heart disease. Without prompt treatment, this condition can lead to tissue damage, organ dysfunction, and loss of the affected limb. ALI is a medical emergency and requires immediate care.

ALI symptoms are often severe and sudden. They can be remembered with the "six Ps": 

• Pain: sudden severe pain in the limb, even when at rest 
• Pallor: the limb may appear pale 
• Pulselessness: absent or diminished pulse in the limb 
• Paresthesia: a tingling or prickling sensation, or numbness 
• Paralysis: loss of movement in the limb, which is a late and grave sign 
• Poikilothermia: the limb feels colder than the rest of the body 

ALI can be caused by the following: 

• Embolism: A blood clot from elsewhere in the body blocks a limb artery. 
• Thrombosis: A clot forms inside an artery that is already narrowed by plaque. 
• Trauma: Injury to an artery.

ALI risk factors include heart conditions, irregular heartbeat, atherosclerosis, previous clots, and smoking.

Talking to a Doctor 

If a patient experiences any of the previously described symptoms, they should seek medical attention immediately. ALI is an emergency condition. Patients should discuss any risk factors with their doctors and seek a referral to a vascular surgeon if concerned about ALI. 

Role of Vascular Surgeon 

Vascular surgeons are experts in diagnosing and treating vascular conditions such as ALI. Vascular surgeons are trained to perform emergency procedures that can restore blood flow and save the affected limb. 

Diagnosis 

Diagnosis usually involves urgent assessment by a vascular surgeon and may include: 

• During physical examination, checking for the presence of pulses in the limb. 
• Conducting Doppler ultrasound to assess blood flow and locate any blockages. 
• Angiography, which involves injecting a contrast dye into the arteries to visualize blockages on X-ray images. 
• Using CT scan to identify blockages of the blood vessels. 

Treatment aims to restore blood flow quickly. It may include: 

• Medications to dissolve clots or prevent new ones 
• Catheter-directed thrombolysis to deliver clot-dissolving drugs directly to the site of the clot 
• Catheter-based thrombectomy, which uses a tube inserted into the artery to remove the blood clot  
• Surgical procedures to remove the clot or bypass the blocked artery 
• Angioplasty or stenting to open the narrowed arteries and maintain blood flow 

Time is critical in treating ALI to prevent permanent damage. If a patient suspects they are experiencing ALI, they should seek immediate emergency care.