Caring for Patients with Vascular Problems

Peripheral vascular disease includes disorders that change the natural flow of blood through the blood vessels of peripheral circulation, and includes peripheral artery disease, or PAD, and peripheral venous disease.

PAD is characterized by a partial or total blockage of blood flow through arteries, which are high-pressure vessels that carry oxygen and nutrient-rich blood from the heart to the tissues.

Blockage results in decreased perfusion and impaired delivery of oxygen,
and nutrients to the tissues below the level of obstruction, causing tissue hypoxia and ischemia.

The most common cause of PAD is atherosclerosis, or the build-up of plaque within the artery. Risk factors for atherosclerosis include smoking, uncontrolled hypertension, uncontrolled diabetes mellitus, and hyperlipidemia.

On the other hand, peripheral venous disease is the result of prolonged pressure in the veins, which are low-pressure vessels that return deoxygenated and nutrient-depleted blood back to the heart.

In the legs, the veins have to work against gravity to move blood up to the heart. To do this, they depend on the skeletal muscle pump, or the contraction of surrounding skeletal muscles, to compress the veins and propel blood upwards. These veins also have one-way valves that prevent blood from flowing backwards, away from the heart. If the valves fail to close properly, a condition called venous insufficiency, blood leaks backward and pools in the veins, causing venous hypertension, or high pressure within the veins. Over time, the veins become distended and twisted, as the pressure inside the veins increases. Venous hypertension can also occur when a blood clot, or thrombosis, obstructs blood flow.

Common causes of peripheral venous disease include venous stasis, or slowing of blood through the vascular system; vascular injury; and hypercoagulable states.

Also, people who have occupations that require prolonged standing, like nurses or teachers, or those who have a family history of varicose veins, are more likely to develop peripheral venous disease.

Now, clinical manifestations of PAD include cramping or burning leg pain that worsens with activity and improves with rest, known as intermittent claudication. At rest, patients may feel numbness or sometimes a burning sensation.

The lower extremities are often cool to the touch, and appear hairless, shiny, dry, scaly, and dusky or mottled, with thickened toenails. When elevated, the lower extremities may appear pale, and when dependent, they may become red, called dependent rubor. As the disease progresses, they develop ulcers, that are typically small, painful, with well-defined borders that occur between the toes or on the upper aspect of the foot. Gangrene may also develop if it’s left untreated.

Conversely, those with peripheral venous disease typically have edema, as fluid starts to leak out of the veins and into the surrounding tissues. The stagnant blood in the vessels and the surrounding tissues leads to fibrosis and ulcers, called venous stasis ulcers which are deep pink or red with irregular borders, typically found over the medial malleolus. Other symptoms include hyperpigmentation, pruritus, and pain that usually occurs at rest, unlike PAD.

Diagnosis starts with the patient’s history and physical examination.