Pressure ulcers remain the biggest challenge wound care practitioners face today. Localized sites of cell death, pressure ulcers occur most commonly in areas of compromised circulation secondary to pressure. They may be superficial, caused by local skin irritation with subsequent surface maceration, or deep, originating in underlying tissue. Deep tissue ulcers may go undetected until they penetrate the skin.

In most cases, pressure ulcers develop when soft tissue is compressed between a bony prominence (such as the sacrum) and an external surface (such as a mattress or the seat of a chair) for a prolonged period. Pressure-applied with great force for a short period or with less force over a longer period-disrupts blood supply to the capillary network, impeding blood flow to the surrounding tissues and depriving tissues of oxygen and nutrients. This leads to local ischemia, hypoxia, edema, inflammation, and, ultimately, cell death. The result is a pressure ulcer.

The presence of shear, which separates the skin from underlying tissues, and friction, which abrades the top layer of the skin, also contributes to pressure ulcer development. Contributing systemic factors include infection, malnutrition, edema, obesity, emaciation, multisystem trauma, and certain circulatory and endocrine disorders.

Managing Tissue Loads

Support surfaces (or tissue load-management surfaces) are a major therapeutic means to managing pressure, friction, and shear on tissues. In addition, many support surfaces help control moisture and inhibit bacterial growth. Support surfaces are available in various sizes and shapes for use on beds, chairs, examination tables, and operating department tables. Used with proper topical skin and wound care, turning, and repositioning, the correct support surface enhances healing of pressure ulcers and helps prevent new ones.

The support surface is not the only intervention that should be used to prevent pressure ulcers from occurring. As exemplified by the Agency for Healthcare Research and Quality (formerly the Agency for Health Care Policy and Research), effective turning and positioning schedules are the best way to offset pressure in the immobile patient.

* Repositioning. At-risk patients in bed should be repositioned at least every 2 hours if consistent with overall patient goals. A written schedule for systematically turning and repositioning the individual should be used.

* Positioning devices. For individuals in bed, positioning devices such as pillows or foam wedges should be used to keep bony prominences (eg, knees or ankles) from direct contact with one another, according to a written plan.

* Pressure relief for the heels. Individuals in bed who are immobile should have a care plan that includes the use of devices that totally relieve pressure on the heels, most commonly by raising the heels off the bed. Do not use donut-type devices.

* Side-lying positions. When the patient is in the side-lying position in bed, avoid positioning directly on the trochanter.

* Bed positioning. Maintain the head of the bed at the lowest degree of elevation consistent with medical conditions and other restrictions. Limit the amount of time the head of the bed is elevated.

* Lifting devices. Use lifting devices such as a trapeze or bed linen to move (rather than drag) individuals in bed who cannot assist during transfers and position changes.

* Pressure-reducing devices for beds. Any individual assessed as having a risk for developing pressure ulcers should be placed, when lying on bed, on a pressure-reducing device, such as foam, static air, alternating air, gel, or water mattresses.

* Pressure from sitting. At-risk individuals should avoid uninterrupted sitting on a chair or wheelchair. The individual should be repositioned, shifting the points under pressure at least every hour, or be put back to bed if consistent with overall patient management goals. If they are capable, patients should be taught to shift weight every 15 minutes.

* Pressure-reducing devices for chairs. For chair-bound patients, the use of a pressure-reducing device, such as those made of foam, gel, air, or a combination, is indicated. Do not use donut-type devices.

* Postural alignment. Positioning of chair-bound patients should include consideration of postural alignment, distribution of weight, balance and stability, and pressure relief.

* Plans and scheduling. A written plan for the use of positioning devices and schedules may be helpful for chair- and bed-bound patients.

End Points

Using these strategies in a comprehensive plan of care addresses the first line of defense for patients at risk for skin breakdown. The Wound, Ostomy, and Continence Nurses Society (http://www.wocn.org) has recently published additional strategies.

Pressure ulcers occur in patients in all health care settings. On admission, clinicians should initiate proper procedures and the use of support surfaces to prevent and treat existing pressure ulcers. It is also important to keep in mind that not all products meet the particular criteria for each individual patient. Effective interventions demand a multidisciplinary team approach that coordinates the needs of the patient.

Source: Hess CT. Clinical Guide: Skin & Wound Care; 6th ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008.