Ischaemic Skin Ulcer

arterial ulcer, arterial insufficiency ulcer, ischemic wound

Ischaemic skin ulcers are painful, slow-healing wounds that develop when tissues do not receive enough blood, oxygen, and nutrients due to narrowed or blocked arteries, most commonly affecting the feet and legs.

Table of contents

• What is an ischaemic skin ulcer?
• Where do these ulcers occur?
• What causes ischaemic ulcers?
• Who is at risk?
• Signs and symptoms
• How is it diagnosed?
• Treatment approaches
• Wound care basics
• Prevention strategies
• When to see a doctor

What is an ischaemic skin ulcer?

An ischaemic skin ulcer is a type of wound or sore that develops when the arteries cannot deliver enough blood flow to a specific area of the body^[1]. The term ischaemic (also spelled ischemic) means reduced blood flow to an area of the body. This lack of blood results in a decreased supply of oxygen and nutrients to tissues, causing damage and cell death, which is when cells in the tissue die^[2].

When tissues do not receive enough oxygen and nutrients due to restricted blood flow, they begin to die, damaging the tissue and leading to the formation of painful ulcers that are slow to heal or may not heal at all^[1]. Poor blood flow causes cells to die and damages tissue, and this damaged tissue that does not get enough blood flow tends to heal more slowly than normal wounds^[1].

These types of wounds can be particularly challenging because the very condition that causes them—poor circulation—also makes healing difficult. It is rare for an ischaemic ulcer to heal if nothing can be done to improve the arterial blood supply to the affected area^[3].

Where do these ulcers occur?

Most ischaemic ulcers occur on the feet and legs^[1]. Ischaemic ulcers most commonly affect the lower limbs, particularly the feet and toes^[2]. These areas are the farthest from the heart and are therefore more vulnerable to reduced blood flow due to circulation problems.

More specifically, ischaemic ulcers usually develop on the feet, frequently on the heels, tips of toes, or between the toes in patients with vascular disease^[3]. They can also occur in the nail bed if the toenail cuts into the skin or if the patient has had recent aggressive toe nail trimming or an ingrown toenail removed^[3]. The ulcer is usually found on skin over pressure points such as the tip of the toe, the heel, or the inner side of the ankle bone^[6].

The lower legs are also prone to swelling and pressure, which can further compromise blood flow and contribute to the development of ischaemic ulcers^[2]. While ischaemic ulcers are primarily a skin condition, they can also affect internal organs, such as the colon^[2].

What causes ischaemic ulcers?

Narrowed arteries, a condition called atherosclerosis, are the most common cause of ischaemic ulcers^[1]. Atherosclerosis is when fat, cholesterol, and other substances build up in the walls of arteries, causing them to narrow. Narrowed arteries prevent a healthy supply of blood from flowing to the legs, which means that the tissues in the legs do not get enough nutrients and oxygen^[1].

The lack of nutrients causes cells to die, damaging the tissue^[1]. Damaged tissue that does not get enough blood flow also tends to heal more slowly. Several conditions can lead to narrowed arteries and reduced blood flow, including peripheral artery disease (PAD), which is a condition that can be a complication of diabetes, high blood pressure, and high cholesterol levels^[2].

Other conditions that can lead to ischaemic ulcers include heart disease, cerebrovascular disease (diseases affecting blood vessels in the brain), blood clotting disorders, and venous insufficiency (when veins have trouble sending blood from the limbs back to the heart)^[2].

An injury, even a small one, can become an ulcer if not enough blood can reach it to help it heal^[6]. Often, the ulcer occurs where the skin rubs against clothing or shoes^[6]. It may also happen at the site of an injury, even a small one that would not normally be expected to cause a problem. Sometimes the ulcer can start as a small dark spot that is painful and grows bigger.

Who is at risk?

Anyone with poor circulation is at risk for ischaemic wounds^[1]. Several factors and conditions can increase the chances that a person will develop ischaemic ulcers. These risk factors include:

• Peripheral arterial disease, which affects blood flow to the limbs^[3]
• Smoking or tobacco use^[3]
• Diabetes^[3]
• High blood pressure^[1]
• High cholesterol levels^[1]
• High levels of fats in the blood (hyperlipidemia)^[3]
• Chronic kidney disease^[1]
• Obesity^[3]
• Physical inactivity^[3]
• Family history of vascular disease^[3]
• Joint or skeletal disease in the lower limbs^[2]
• Higher body mass index^[2]
• Diseases that cause blood vessel inflammation, such as lupus^[1]
• Blockage of the lymph vessels, which causes fluid to build up in the legs^[1]
• Older age^[3]

People with poor blood flow often also have nerve damage or foot ulcers from diabetes^[1]. Nerve damage makes it harder to feel an area in the shoe that rubs and causes a sore. Once a sore forms, poor blood flow makes it harder for the sore to heal.

Many of these risk factors cannot be controlled, but many of the most significant risk factors can be affected or improved by changes in lifestyle^[3]. Controllable risk factors include stopping tobacco use, increasing physical activity, losing weight, managing diabetes, treating high cholesterol and high blood fats, managing high blood pressure, and using blood-thinning medications when indicated^[3].

Signs and symptoms

Ischaemic ulcers have several distinctive characteristics that help identify them. Symptoms of ischaemic ulcers include^[1]:

• Wounds may appear on legs, ankles, toes, and between toes
• Dark red, yellow, gray, or black sores
• Raised edges around the wound that look “punched out”^[1]
• No bleeding from the ulcer^[1]
• Deep wound through which tendons may show
• Wounds that may or may not be painful
• Pain and discomfort, especially at night^[2]
• Aching pain in the foot or leg, often at night, which may go away when the leg is dangled down^[1]

The surrounding skin also shows characteristic changes. The skin on the leg appears shiny, tight, dry, and hairless^[1]. The surrounding area may be pale and cool, suggesting poor blood supply^[3]. Dangling the leg down off the side of a bed or chair causes the leg to turn red, and when the leg is raised, it turns pale and cool to the touch^[1].

The ulcers often have a symmetrical shape with well-defined borders and a “punched out” appearance^[2]. The base of the wound can be yellow, brown, gray, or black in color^[3]. Unlike some other wounds, because low blood circulation is the primary cause of these types of ulcers, they typically do not bleed^[3].

Additional warning signs that require immediate medical attention include drainage from the ulcer, redness around the ulcer, swelling, redness extending up the leg, pain on motion of toes, fever over 101 degrees F (39°C), chills, skin blisters and weeping, and gangrene (wet or dry), which is when tissue dies due to lack of blood supply^[3].

How is it diagnosed?

A full medical history of the patient is evaluated^[3]. A wound specialist will examine the wound thoroughly and begin initial therapy. The doctor will look at the ulcer and ask questions about health^[6]. The doctor may press on the skin around the ulcer and check the pulses on the leg and foot.

Laboratory testing and imaging studies may be performed to help diagnose the problems and develop a treatment plan^[3]. These may include noninvasive vascular studies, X-rays, CT scans, and MRI scans. Tests may also be done to show how well blood is flowing through the arteries of the leg^[6].

A multidisciplinary approach involving the staff of the care center, the primary care physician, and specialists increases the likelihood of correct diagnosis, successful wound healing, and prevention of complications or recurrence^[3].

Treatment approaches

To treat an ischaemic ulcer, blood flow to the legs needs to be restored^[1]. This is the core requirement for treating an ischaemic ulcer. Treatment may include taking medicine, and in some cases, surgery may be needed^[1].

Medical procedures to improve blood flow may include a procedure to open a narrowed or blocked blood vessel called angioplasty^[6]. Alternatively, surgery may be done to attach a new artery on both ends of a blockage so blood can go around the part of the blood vessel that is blocked, which is called bypass surgery^[6].

Treatment also includes medicines, such as aspirin, if needed to help prevent more problems with blood vessels or blood flow^[6]. If there is pain, the doctor will help manage it^[6].

Specific treatment measures for ischaemic ulcers include^[3]:

• Removal of dead tissue from the wound (debridement)
• Appropriate dressing of the wound
• Treatment of infection and inflammation
• Protection of the wound
• Sometimes surgery to improve blood supply
• Sometimes hyperbaric oxygen therapy
• Management of wound pain
• Treatment of diabetes and attention to nutrition
• Advanced therapies to stimulate tissue growth

In some cases, the tissue in the toes or the foot is too damaged to be saved^[6]. When that happens, the affected part of the leg or foot may have to be removed (amputated). These difficult to heal foot ulcers frequently require weeks to months to completely heal, and many of the treatment methods used are demanding and time-consuming^[3].

Wound care basics

The healthcare provider will show how to care for the wound^[1]. The basic instructions are:

• Always keep the wound clean and bandaged to prevent infection^[1]
• The provider will tell how often to change the dressing
• Keep the dressing and the skin around it dry
• Try not to get healthy tissue around the wound too wet, as this can soften the healthy tissue, causing the wound to get bigger^[1]
• Before applying a dressing, clean the wound thoroughly according to the provider’s instructions^[1]

Treatment also includes care of the wound using special coverings on the ulcer that will help protect the area and prevent infection^[6]. Taking antibiotics if there is an infection and removing dead tissue from the wound are also important parts of wound care^[6].

The person may be able to change their own dressing, or family members may be able to help^[1]. A visiting nurse may also help. Follow the doctor’s instructions about keeping pressure off the leg or foot ulcer^[6]. It may be necessary to use crutches or a wheelchair, or to wear a cast or a walking boot.

Prevention strategies

If a person is at risk for ischaemic ulcers, taking certain steps may help prevent problems^[1]:

Daily foot and leg care:

• Check feet and legs every day, including the tops and bottoms, ankles, heels, and between toes^[1]
• Look for changes in color and red or sore areas
• Keep the skin of legs and feet moisturized^[6]
• Check the skin of feet daily for small cuts and scrapes^[6]

Proper footwear and protection:

• Wear shoes that fit properly and do not rub or put pressure on feet^[1]
• Wear socks that fit properly; socks that are too big can bunch up in shoes and cause rubbing of the skin, which can lead to a sore^[1]
• Do not walk barefoot; protect feet from injury^[1]
• Protect feet from the cold^[1]

Activity and positioning:

• Try not to sit or stand too long in one position^[1]
• Exercise as much as possible; staying active can help with blood flow^[1]

Important precautions:

• Do not wear compression stockings or wraps unless told to by a provider, as these may restrict blood flow^[1]
• Do not soak feet in hot water^[1]

Certain lifestyle changes can help prevent ischaemic ulcers and, if a wound exists, can improve blood flow and aid healing^[1]:

• Quit smoking, as smoking can lead to narrowed arteries^[1]
• If a person has diabetes, keep blood sugar level under control, as this will help heal faster^[1]
• Exercise as much as possible to improve blood flow^[1]
• Eat healthy foods and get plenty of sleep at night^[1]
• Lose weight if overweight^[1]
• Manage blood pressure and cholesterol levels^[1]

When to see a doctor

Any ulcer on an extremity in a patient with vascular disease that does not heal promptly is a probable ischaemic ulcer that might benefit from specialized care^[3]. A multidisciplinary approach involving the surgeon, the staff of the care center, the primary care physician, and vascular surgeon increases the likelihood of successful wound healing and prevention of complications or recurrence^[3].

Call the healthcare provider if there are any signs of infection, such as^[1]:

• Redness, increased warmth, or swelling around the wound
• More drainage than before or drainage that is yellowish or cloudy
• Bleeding
• Odor
• Fever or chills
• Increased pain

There must be a real commitment by the patient and their caregivers to follow through with the recommendations and treatments as scheduled^[3]. Partial or incomplete therapy almost always results in failure to heal. The ultimate consequence of failure to heal is loss of limb or life^[3].