A pressure ulcer is an area of skin and tissue damaged by prolonged pressure that cuts off oxygen and nutrients. Depriving oxygen and nutrients from specific areas can cause the death of skin and, eventually, the underlying tissues.

Not all ulcers are pressure ulcers. An ulcer is any open sore or break in the skin that extends beyond the top layer of skin (epidermis) and is accompanied by the sloughing off of dead tissue. Friction or trauma may also result in ulcers by wearing away or cutting past the skin.

Patients who have limited mobility, such as those confined to wheelchairs, and are confined to bed for long periods of time are at risk of developing pressure ulcers. Although pressure ulcers can occur in anyone with limited mobility, paralyzed and comatose people are at higher risk because they are unable to shift and move, which relieves the pressure and restores circulation. People with certain medical conditions, such as diabetes, are also more likely to develop pressure ulcers.

Pressure ulcers are usually painful and may be itchy. They are easily infected, resulting in thick pus, a foul odor, warmth, redness and swelling around the sore. The infection may spread to the underlying muscle and even the bone, leading to serious medical problems.

Pressure ulcers are generally treated by keeping sores clean, covered and free of dead tissue. When infection occurs, antibiotics are used. Severe pressure ulcers, however, may require surgical treatment.

A pressure ulcer (also called pressure sore, decubitus ulcer, bed sore) is damage to the skin and, in more serious cases, the underlying tissue. It is caused by impaired circulation due to pressure on a specific area. The skin begins to die when the supply of blood is stopped. Pressure ulcers most commonly occur in individuals who spend a majority of their time in a bed or chair without repositioning, such as people in hospitals or nursing homes.

Pressure ulcers also may occur from straps, splints, casts or ill-fitting clothes. Ulcers break the protective barrier of the skin and thus are prone to infection. When pressure ulcers become infected (bacteria or viruses come into contact with the ulcer and begin to grow there), they form pus.

Bony areas beneath the skin and areas in contact with a bed or chair are more vulnerable to developing pressure ulcers. These body parts include the elbows, shoulders, back, buttocks, hips, ankles, heels and the back of the head. Sustained pressure can kill skin and tissue in less than 12 hours. If normal circulation is not restored, the damage may be irreversible.

Pressure ulcers frequently become infected. Untreated, the infection can spread throughout the body with serious or even fatal consequences. An infected ulcer may exude thick green or yellow pus, as well as a foul odor. The skin around the ulcer may redden, swell and feel tender.

Not all ulcers are pressure ulcers. The term ulcer refers to any open sore or break in the skin that extends into the middle layer of the skin (dermis) or below and is accompanied by the sloughing off of dead tissue. There are many different types of ulcers depending on the cause (e.g., injury, pressure, sheering forces), duration and progression.

Pressure ulcers often heal on their own when they are detected early and the source of pressure is removed. However, serious cases, such as pressure ulcers that move through the entire thickness of a body part (perforating ulcer), can lead to infection of the underlying muscle and even of the bone. These conditions are dangerous and often require serious medical intervention, such as an amputation of a limb.

Pressure ulcers may surround a body part and destroy tissue to the bone (amputating ulcer). In some cases, ulcers may not heal (atonic ulcers) or they may extend to another area as the previous area heals (serpiginous or creeping ulcer). Ulcers that rapidly spread as tissue deteriorates and dead tissue is discharged are called phagedenic ulcers.

There are six stages of pressure ulcers:

• Stage 1: Skin is red or may appear dusky but remains intact. The area may also feel warmer than the surrounding skin.
  
  
• Stage 2: Skin is swollen and often has blisters (raised areas on the skin surface that contain fluid).
  
  
• Stage 3: The sore has ulcerated, revealing deeper layers of skin.
  
  
• Stage 4: The sore extends into muscle.
  
  
• Stage 5: Muscle is destroyed.
  
  
• Stage 6: Bone is exposed, damaged and possibly infected.

Pressure ulcers may be formed by a number of different processes. The common cause of a pressure ulcer is unrelieved pressure that squeezes the blood vessels and cuts off the supply of oxygen and nutrients to the skin.

When body parts do not receive enough oxygen and nutrients, they begin to die and form ulcers. Pressure is worst in bony areas, where bones cause a great deal of force on the skin and tissue and press them against an outside surface.

Pressure ulcers can also form when tissues shift against each other or in the opposite direction as the bone (e.g., when sliding down in a bed or a chair). The blood vessels may stretch or bend, cutting off circulation. External pressure is generally more likely to cause an ulcer than these shearing forces alone, but the two factors often combine to exacerbate the risk.

Ulcers may also form due to friction that wears away the top layers of the skin. Poorly fitting clothing can cause this friction. Other causes of ulcers include:

• Impaired circulation. If the blood does not circulate properly, certain body parts may be deprived of needed oxygen and nutrients. Ulcers caused by impaired circulation alone are not pressure ulcers. However, impaired circulation can increase the risk of pressure ulcers.
  
  
• Anemia. A reduction in red blood cells that reduces the amount of oxygen delivered to body parts. Ulcers caused by anemia alone are not pressure ulcers. However, anemia can increase the risk of pressure ulcers.

Some people have an increased risk of developing pressure ulcers. Risk factors include:

• Old age or fragile skin. Elderly people tend to have thinner skin. When the skin is thin or fragile, it tears more easily, which may result in pressure ulcers.
  
  
• Immobility. People confined to a bed or wheelchair may be unable to shift their weight, resulting in pressure ulcers.
  
  
• Smoking. Nicotine impairs circulation and slows healing.
  
  
• Malnourishment. Lack of protein, vitamins and other nutrients impairs skin integrity and slows healing.
  
  
• Excessive thinness or weight loss. If there is not enough fat to cushion pressure, pressure ulcers may be more likely to form.
  
  
• Urinary or fecal incontinence (loss of bladder or bowel control). These conditions result in excessive moisture remaining on the skin, making it more fragile and more easily torn. The areas are also not clean, increasing the risk of infection.
  
  
• Contractures (shortening of the muscles, tendons and ligaments around a joint). This condition causes increased friction and shearing forces.

People who cannot feel or recognize discomfort or pain may not be able to shift their weight often enough, resulting in pressure ulcers. People with nerve damage cannot sense discomfort or pain causing the tissue breakdown.

This is why people with diabetes, which often causes nerve damage, are at higher risk for developing pressure ulcers. Other illnesses that may increase the risk of ulcer development include:

• Sickle cell disease (an inherited blood disease)
  
  
• Syphilis (an infectious disease that results in ulcers and rashes)
  
  
• Lupus (a chronic inflammatory disease that can affect the skin, as well as the joints, blood, kidneys and various other body parts)
  
  
• Leprosy (an infectious disease characterized by skin lesions and nerve damage)

Regular self-monitoring and appointments with a physician play important roles in preventing pressure ulcers from becoming worse. Visual inspection is crucial for detecting pressure ulcers in time to prevent complications.

Pressure ulcers are typically diagnosed by physicians during physical examination of the patient. The severity is determined by examining the site and assessing the depth of the ulceration. Blood tests, x-rays and often more sophisticated imaging techniques (like CT scan or MRI) may also be necessary to determine if the ulcer is infected or involves underlying soft tissue or bone. 

Pressure ulcers can cause serious or even fatal complications. If not treated or relieved in time, irreversible skin damage can occur in less than 12 hours. Treatment of pressure ulcers varies with the type and severity of the sore. Common treatment of pressure ulcers includes:

• Relief of pressure.  Removing or at least decreasing pressure from the ulcer is considered the most important aspect of pressure ulcer treatment and is very important in keeping ulcers from getting bigger. Most pressure ulcers in the early stages heal on their own once pressure is relieved. This can be simply accomplished by frequent repositioning so that the body’s weight is dispersed off the injured area. Physicians may also recommend special equipment such as pillows, foam cushions or padding, sheepskin, special mattresses or mattress covers. 
  
  
• Debridement (removal of dead tissue). It is important to keep pressure ulcers clean and free from dead tissue. This is typically accomplished with debridement by scalpel, saline (salt water) rinses, chemicals, or whirlpool treatments.
  
  
• Proper dressing. Dressings range from ordinary bandages to antibiotic (combat bacteria) and antiviral (combat viruses) coverings. Particularly useful forms of dressings for pressure ulcers include:
  
  
• • Transparent adhesive dressings. These allow the air to reach the pressure ulcer and prevent it from increasing in size as well as reducing the risk of infection. However, because they are not absorbent, they are not typically recommended for pressure ulcers that have significant discharge.
    
    
  • Hydrocolloid dressing. A bandage with particles that interact with the pressure ulcer to form a gel. These dressings absorb some of the drainage from pressure ulcers, keep the affected areas moist and have properties that enhance healing and protect against infection.
    
    
  • Gel dressings. Available in sheet form or as granules or liquid gel. As long as gel dressings are not allowed to dehydrate, they keep the affected area moist to encourage healing. Some forms absorb moderate amounts of discharge, and can provide insulation or protection against infection.
    
    
  • Calcium alginate dressings. Derived from brown seaweed, these dressings are highly absorbent and easy to use. They are extremely effective in treating pressure ulcers with large amounts of discharge and infection.
    
    
• Antibiotics. Infections must be controlled at the early stage to prevent worsening of the condition and spreading in the body. If the infection is present only in the ulcer, topical (applied to the skin) antibiotics are typically sufficient. However, if the infection has spread, oral or intravenous antibiotics may be necessary.
  
  
• Skin substitutes. A dissolvable mesh containing a product made from the human cells that make connective tissue is placed on the sore. The skin substitute is absorbed, replaces the damaged area and closes the lesion.
  
  
• Topical human growth factor. Gel containing a genetically engineered platelet-derived growth factor is applied to the pressure ulcer. The gel attracts and fosters the spread of the cells that repair sores and create tissue.
  
  
• Diet. When the body is healing damaged tissue, it expends more energy and increased calories are required. In particular, meals high in protein are essential for repair.  A diet that also includes adequate fluids and foods rich in vitamins and other nutrients can speed repair of damaged tissues.
  
  
• Exercise. Walking, building muscle strength and physical therapy can help resolve pressure ulcers.
  
  
• Skin grafting or tissue flaps. Tissue transplants may be necessary in severe cases. Depending on the depth of the pressure ulcer, skin alone or a flap of muscle, skin and other tissue may be used to cover the sore.
  
  
• Vascular surgery. Surgery on the blood vessels to improve circulation to the legs might be necessary if blockage is severe and unresolved by noninvasive procedures.

A pressure ulcer will begin to decrease in size and become less moist as it begins to heal. Over time, healthy replacement tissue (called granulation tissue) develops at the base of the sore that is pink-to-light red in color and often has a cobble-stone appearance. 

Depending on the severity of the sore, a pressure ulcer can take anywhere from a few days to an entire year before it is completely healed. In some people, particularly those with certain underlying chronic conditions (e.g., diabetes), a pressure ulcer may never heal completely.  

Prevention is important with pressure ulcers. Steps to prevent pressure ulcers and further complications include:

• Daily skin inspection. Routinely check for any sign of breakdown in the skin barrier like cuts, blisters (raised areas on the skin surface that contain fluid), sores, or cracks. It is especially important to examine bony areas of the body (e.g., elbow, heels, hips, ankles, shoulders, back, back of the head). A mirror can help. Patients should immediately notify their physician if a problem is present.
  
  
• Daily hygiene. The skin should be gently but thoroughly washed and patted dry. A physician can recommend whether to use balms, lotions or powders to protect the skin. Generally, creams and oils should not be used in certain areas (e.g., between the toes) because the moisture can result in infection and skin breakdown. Nails should be trimmed along the contour of the finger or toe and any sharp edges filed. When bathing, warm (not hot) water and mild soaps are generally recommended.
  
  
• Properly fitting clothing. Correct fit of clothing is an important factor in pressure ulcer prevention. Thick seams or buckles and other fixtures may increase friction on the skin. Buying shoes late in the day can ensure a better fit because the feet tend to be less swollen in the morning. Having at least two pairs of shoes and alternating them every other day reduces the risk of pressure in the same location on the foot.
  
  
• Prevention or cessation of smoking. Smoking increases the risk of pressure ulcers because it impedes circulation.
  
  
• Control of high cholesterol (a fatty substance found in foods and produced by the body). High levels of cholesterol and other fats in the blood increase the risk of atherosclerosis, the hardening of the arteries that is a risk factor for pressure ulcers.
  
  
• Diabetes control. Close control of blood sugar results in better skin condition and a reduced risk of medical complications.
  
  
• Proper nutrition. Healthy skin is less likely to be damaged. It is important to eat a balanced diet with plenty of protein and calories.

Prevention of pressure ulcers also includes:

• Teaching patients how to shift weight in a wheelchair or bed
  
  
• Repositioning frequently, generally every two hours, by lifting rather than sliding the patient
  
  
• Avoiding donut-shape (ring) cushions, which may block circulation
  
  
• Using special mattresses or wheelchair cushions
  
  
• Protection of prominent bony areas with padding
  
  
• Avoiding massage over bony parts of the body

Preparing questions in advance can help patients to have more meaningful discussions with their physicians regarding their conditions. Patients may wish to ask their doctors the following questions about pressure ulcers:

1. Am I at risk for pressure ulcers?
   
   
2. Do my symptoms indicate a pressure ulcer?
   
   
3. What specifically caused my pressure ulcer?
   
   
4. Could my pressure ulcer be related to an underlying systemic condition?
   
   
5. How severe is my pressure ulcer?
   
   
6. Does my pressure ulcer pose a danger to my overall health?
   
   
7. When can I expect my symptoms to subside?
   
   
8. What are my treatment options?
   
   
9. Am I likely to develop pressure ulcers again in the future?
   
   
10. How can I prevent further pressure ulcers?