Chapter 144. Pressure Ulcers

1. What is a pressure ulcer and how do you stage severity?

2. How do you assess individual risk for the development of pressure ulcers?

3. What measures are effective in pressure ulcer prevention?

4. How should pressure ulcers be cleansed, debrided, and dressed?

5. What role do adjunctive therapies have in pressure ulcer treatment?

Pressure ulcers, or “bedsores,” are a key clinical indicator of quality of care in hospitals. Their occurrence is widely seen as a marker for substandard care, triggering anger and sometimes litigation on the part of patients and families. However, they remain common in hospitalized patients. In 1993, pressure ulcers were diagnosed during 280,000 hospital stays in the United States, a number that rose to 455,000 in 2004. Up to 15% of elderly patients develop pressure ulcers within the first week of hospitalization. Mortality may be as high as 60% for older persons with pressure ulcers in the year after hospital discharge.

Pressure ulcers are also expensive, with an average charge per stay of $43,180. In 2007, the Centers for Medicare and Medicaid Services (CMS) made payouts of more than $11 billion for beneficiaries admitted to hospitals who developed stage III and stage IV pressure ulcers. The Centers for Medicare and Medicaid Services subsequently stopped reimbursement for hospital-acquired stage III and stage IV pressure ulcers in October 2008.

Pressure ulcers are focal injuries of skin and subcutaneous tissue resulting from pressure, shear forces, friction, or some combination of these. They most often overlie bony prominences of the pelvis and lower extremities, such as the sacrum, greater trochanter of the hip, and heels, but they may appear in other locations, depending on patient positioning (Figure 144-1).

Tissue ischemia occurs when external pressures exceed perfusion pressures. Normal blood pressure within capillaries ranges from 20 to 40 mm Hg; 32 mm Hg is considered average. An external pressure less than 32 mm Hg usually suffices to prevent pressure ulcers. However, capillary blood pressure may be less than 32 mm Hg in critically ill patients due to hemodynamic instability and comorbid conditions.

Frictional forces, like those generated between the heels and bedsheets, can lead to blisters and skin breakdown, favoring the development of pressure ulcers. Bedbound patients are also prone to shear forces, which occur when bone and soft tissue move relative to the skin, which is held in place by friction.

Older patients are more susceptible to shear forces, as their soft tissues are atrophied and contain less elastin. Moisture, as in urine, stool, and sweat, acts synergistically with pressure, friction, and shear forces to facilitate ...