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Part II Nutrition Assessment, Consequences, and Implications BOX 15.1 Selected Nutrients That Play a Role in Prevention and Treatment of Pressure Ulcers

Calories Calories provide adequate energy to support body functions, prevent weight loss, and preserve lean body mass. Die- tary carbohydrate, protein, and fat are all sources of calories. Dietary carbohydrates are an important energy source because they are protein-sparing; without adequate carbohydrates, protein stores are used for energy use, resulting in loss of lean body mass and poor wound healing.

Protein

Protein contains nitrogen, which is essential for wound healing. It is responsible for repair and synthesis of enzymes that are involved in wound healing, cell growth and division, and synthesis of collagen and connective tissue needed to heal a wound. Protein is also a component of antibodies needed for the immune system.

Water

Water serves many vital functions in wound healing, including aiding in oxygen perfusion; helping to maintain body temperature; acting as a solvent for vitamins, minerals, amino acids, and glucose; transporting materials to cells; and removing waste from cells.

Micronutrients

The micronutrients hypothesized to be related to pressure ulcer healing include vitamin C, zinc, and copper. Vitamin C may increase the activation of leukocytes and macrophages to the wound site and plays a role in collagen forma- tion. Copper is required for cross-linking of collagen fibers in rebuilding tissue. Zinc is an essential cofactor for for- mation of collagen, protein synthesis, DNA, and RNA, and it assists in immune function. Because excess zinc can affect copper status, if zinc supplements are ordered, they should be limited to 40 mg of elemental zinc per day. Du- ration of supplement is not known, but some experts recommend two to three weeks.

Sources: National Pressure Ulcer Advisory Panel, European Pressure Ulcer Advisory Panel, Pan Pacific Pressure Injury Alliance. Prevention and Treatment of Pressure Ulcers: Clinical Practice Guideline. Washington, DC: National Pressure Ulcer Advisory Panel; 2014, and Posthauer ME, Thomas D. Nutrition and wound care. In: Baranoski S, Ayello E, eds. Wound Care Essentials. 3rd ed. Ambler, PA: Lippincott Williams & Wilkins; 2012:240-264.

NUTRITION ASSESSMENT

AND SKIN INTEGRITY Nutrition-focused physical assessment (see Chapter 6) can help identify potential for skin breakdown. Skin color, texture, dryness, temperature, and the presence of lesions or injuries are all characteristics to note (9). “Hot skin may indicate increased blood flow due to inflammation or infection. Cool or cold skin with a white or pale color is suggestive of decreased blood flow and impaired circulation.” Wrinkled, withered, or dry skin is a sign of dehydration. Taut and shiny skin may indicate edema. A careful nutrition-focused physi- cal examination should include an assessment of the degree of body fat and muscle mass loss and the evalu- ation of any fluid accumulation (6).

AVOIDABLE VERSUS UNAVOIDABLE PRESSURE ULCERS

Pressure ulcers are often considered an indicator of poor quality of care, but most experts agree that in some cases they are unavoidable. According to a 2014 NPUAP Consensus Conference on the subject of unavoidable pressure ulcers, “pressure ulcer

development is a multicausal event. In the vast major- ity of cases, appropriate identification and mitigation of risk factors can prevent pressure ulcer formation. However, in some cases pressure ulcers are unavoid- able because (1) the magnitude and severity of risk is overwhelmingly high and/or (2) preventive measures are either contraindicated or inadequate given the magnitude and severity of risk” (10).

Common disease examples where pressure ulcers may be unavoidable include multiorgan failure, sys- temic inflammatory response syndrome (SIRS), sepsis, and critically ill individuals with poor tissue perfusion or decreased tissue tolerance to pressure (10).

MALNUTRITION AND PRESSURE ULCERS

Malnutrition impacts pressure ulcer healing. Both inad- equate nutritional intake and poor nutritional status (malnutrition) have been shown to correlate to the development of pressure ulcers, pressure ulcer severity, and protracted healing of wounds (11,12). Yamamoto, Fujioka et al (2009) reported a correlation between energy intake and pressure ulcer healing in pressure