Acute Limb Ischemia

As an advanced form of peripheral artery disease (PAD), acute limb ischemia (ALI) is typically a leg condition occurring due to a sudden decrease in the amount of blood flow to a limb. While the viability of the limb is at risk, the individual is also at risk for death. The location of the blockage or closure plays a critical role. For instance, an occlusion located in the popliteal artery will result in extreme limb ischemia, because the popliteal artery is the only artery that crosses at the knee level. Yet, if a blockage is noted in the anterior tibial artery, for example, limb ischemia is less threatening, because there are two additional channels (posterior tibial and peroneal arteries) that can provide blood to the foot.

To better understand the risk factors for developing acute limb ischemia, it’s wise to recall the number of Americans that have peripheral artery disease (PAD), which is nearly 8 million. Although age (those over 65), race (African Americans have twice the risk of developing PAD than Caucasians) and gender (women face a greater risk of limb loss when compared to men) play a role in one’s risk of developing some form of PAD, the numbers worldwide are increasing due to other factors such as smoking, hypertension, high cholesterol, diabetes and obesity. In cases of severe limb ischemia, arteries become blocked enough to produce pain, even while resting. Other symptoms may include:

• Pain and tingling in the feet or toes (causing legs and feet to become ultrasensitive, even to the weight of clothes or bed sheets)
• Increasing pain when leg(s) are elevated. In turn, pain may decrease when the leg is allowed to dangle over the side of the bed.
• Skin ulcers (mostly on feet and toes; may appear black)
• Muscle atrophy in calves (muscle shrinking)
• Hair loss on toes and feet
• Thickened toenails
• Skin that appears tight and shiny

When a blood clot forms within the arteries in the legs, symptoms may be abrupt. This is an example of acute limb ischemia and immediate intervention is necessary to avoid limb amputation.

Diagnosis and treatment options for acute limb ischemia

While peripheral artery disease (PAD) is greatly under-diagnosed, the onset of symptoms associated with acute limb ischemia (ALI) tend to set this condition apart. Even so, doctors may use the following P’s as a way to classify acute limb ischemia:

• Pain
• Pallor (paleness)
• Paralysis
• Pulse
• Paresthesia (pins and needles sensation, tingling)
• Poikilothermia (feeling of coldness when compared to other extremities)

In addition, most patients will have experienced claudication in the past or some type of vascular condition (poor circulation) or previous vascular procedure. They will likely report other general factors as well including hypertension, diabetes, smoking and a family history of cardiac conditions.

While the above-mentioned P’s help doctors in diagnosing acute limb ischemia, they also aid in determining the most appropriate type of therapy and treatment needed. For example, pallor and poikilothermia give insight to the progression of the ischemia. The pulse helps doctors determine the site of the blockage, while severe paralysis with an extreme lack of sensation may indicate that the patient’s ischemia is irreversible. While vascular specialists will always work to salvage a patient’s limb with some method of revascularization, there are instances where a complete blockage of an artery has caused severe tissue destruction and amputation of the limb remains the only option.

If the degree of a patient’s ischemia allows for time, and the limb is not immediately threatened, initial treatment includes anticoagulation (Heparin). In turn, endovascular procedures such as catheter-directed thrombolytic (CDT) therapy provides a less complex option that reduces the risk of reperfusion when compared with open surgical procedures. Other non-surgical alternatives may include percutaneous aspiration thrombectomy (PAT) or percutaneous mechanical thrombectomy (PMT). In fact, when used in combination, PAT and PMT may speed up the disintegration of a blood clot, which is important in cases of advanced or critical limb ischemia. Even so, in some cases, fasciotomy (limb saving procedure) is performed, which involves cutting the fascia to treat the loss of circulation to a specific area.

Without question, successful diagnosis, treatment and management of acute limb ischemia involves a complete understanding of the anatomy of the arterial blockage, as well as knowledge of a patient’s present and past health, their family history, lifestyle and consideration of the extent of ischemia they’re experiencing.

With a comprehensive and patient-centered approach, Dr. Alan I. Benvenisty is a highly respected vascular and endovascular surgeon in New York City with extensive experience in the diagnosis and treatment of vascular conditions. His understanding of the ever-changing nature of vascular pathology and the complexity involved in treating conditions such as acute limb ischemia, help patients feel at ease with the moment-to-moment care that Dr. Benvenisty provides. To schedule an appointment with Dr. Benvenisty, contact our office on Amsterdam Avenue today.