Risk Assessment

Prevention programs should include an initial risk assessment of the individual patient. This assessment should include questioning about previous or preexisting pressure ulcers, a thorough skin inspection, evaluating the patient’s mobility/activity level, continence, nutritional status, and a review of comorbid conditions that may contribute to the development of pressure ulcers. Assessment of these risk factors should be standardized and documented on all patients. Several tools have been developed for pressure ulcer risk assessment. The Braden Scale assesses external pressure forces and skin-related factors in a standardized fashion.⁴ The Norton Scale assesses patient-specific risk factors (age, cognitive impairment, mobility, incontinence) for pressure ulcer development.⁵ The Waterlow Scale assesses both intrinsic and extrinsic risk factors and was initially developed for use in the pediatric population.⁶

Prevention Plan

Once the individual patient risk assessment has been addressed, a plan for pressure ulcer prevention should be implemented. Regardless of the plan utilized, a frequent assessment of its efficacy must be performed and any necessary adjustments made. The key elements of prevention include patient mobilization, patient positioning to prevent/remove pressure, and the use of positioning aides to redistribute pressure. Among critically ill patients, this requires vigilance and team effort, particularly among those patients who are sedated for prolonged periods of time. Prevention also includes avoidance of skin damage by shearing forces and avoidance of maceration of the skin due to moisture from incontinence and heat accumulation. There are a variety of support services available to help decrease the risk of pressure ulcer formation. These pressure-reducing surfaces include static support surfaces (mattresses, mattress overlays) and dynamic support surfaces that mechanically alter the amount of pressure applied to the patient’s skin. Examples of dynamic support surfaces include low-air-loss beds, air-fluidized mattresses, and alternating pressure mattresses. The use of foam mattress overlays can reduce the risk of pressure ulcer development in high-risk populations.⁷ Although associated with higher costs, dynamic mattresses have not consistently been shown to be superior to static support surfaces. However, dynamic mattresses are better than standard hospital mattresses in preventing pressure ulcer formation.

Wound Débridement

Débridement of the wound bed is a critical step in the healing process of pressure ulcers. The purpose of débridement is to remove foreign material and devitalized tissue from the wound. After débridement, a wound bed of healthy tissue should be visible. Débridement of the wound bed reduces the production of inflammatory mediators that inhibit wound healing. There are a variety of techniques utilized for wound débridement. These include surgical débridement, hydrotherapy, larval therapy, and application of topical enzymatic débridement solutions. The choice of débridement techniques utilized depends on multiple factors including the size of the wound, comorbid conditions, and the presence of infection. Surgical débridement is most often required in large-volume wounds when extensive tissue débridement is needed. However, surgical débridement requires the patient be a suitable candidate for general anesthesia. The risk of subjecting a critically ill patient to general anesthesia and a trip to the operating room must be weighed against the benefits of sharp surgical débridement of a pressure ulcer. Hydrotherapy, while commonly practiced, has not been rigorously evaluated in the setting of a large randomized controlled trial. However, some small studies of patients with stage III or IV pressure ulcers have demonstrated faster wound healing among patients receiving hydrotherapy as compared to those who did not receive hydrotherapy.^8,9

Larval therapy, also referred to as biosurgery, has been used for débridement of pressure ulcers. The basic concept of larval therapy is that application of larvae to wounds results in rapid débridement of necrotic tissues, with avoidance of the potential complications of surgical débridement such as pain and bleeding. Currently, there is evidence that compared to topical enzymatics, larval therapy significantly reduces the time to débridement of necrotic tissue. However, the use of larval therapy did not appear to have any effect on time to wound healing.¹⁰

A variety of topical enzymatic débridement products are commercially available. These can be used alone or in conjunction with other débridement techniques. These agents are applied directly to the wound bed once or twice a day. Multiple randomized controlled trials have validated the efficacy of topical enzymatic débridement products for the removal of necrotic tissue from the wound bed.¹¹ Prior to applying these agents, the wound bed should be cleansed with normal saline. The presence of any topical wound products containing metal will diminish the efficacy of topical enzymatics, and removing these agents from the wound bed is critical for the success of the enzymatics. In the event an eschar is overlying the wound bed, it is recommended that the eschar be cross-hatched with a surgical blade to allow for penetration of the topical enzymatic agent. Once applied, the wound bed should be covered with gauze. These agents are a viable and valuable therapy, particularly in those patients who are not candidates for alternative débridement methods.

Hydrocolloids

Hydrocolloid dressings are widely used in the management of pressure ulcers; their purpose is to absorb wound exudates. Typical hydrocolloid dressings contain some type of gel-forming agent placed in contact with the wound bed, and this is covered with a membrane that protects the wound against external contamination but allows for water evaporation.¹² Hydrocolloid dressings are typically applied every 3 to 5 days, depending upon the amount of exudates being produced by the wound. When compared to standard gauze dressings, hydrocolloids have been shown to be more absorptive and less painful.¹²

Negative Pressure Therapy

The use of negative pressure therapy for wound healing has become increasingly common in the past decade. The basic concept behind this therapy is that applying negative pressure to the wound bed both removes edema fluid and increases blood flow to the area. Increased blood flow results in delivery of oxygen and nutrients which promote wound healing. In addition, the application of negative pressure to the wound results in wound contracture. Compared to standard wet-to-dry dressings, another benefit to patients of negative pressure therapy is decreased frequency of dressing changes. The use of negative pressure therapy for pressure ulcers has been associated with improved wound healing and decreased length of hospital stay.¹³ Traditionally, negative pressure therapy has been applied to clean wounds that had very little slough or necrotic tissue. However, there is some evidence that the application of negative pressure therapy to wounds that are covered with soft necrotic tissue is a viable option.¹⁴

Nutritional Support

The presence of malnutrition has a significant impact on wound healing. In fact, its mere presence results in weakening of the skin and increases the risk of pressure ulcer development. Unfortunately, nutritional assessment is often neglected, particularly in chronically institutionalized patients. Establishing nutritional assessment protocols as well as treating malnutrition are essential in preventing and healing pressure ulcers. This is best accomplished by a multidisciplinary team that includes physicians, dieticians, and nursing staff.¹⁵

An initial nutritional assessment should be performed. Any recent weight loss, the current weight, and the patient’s dietary intake should all be evaluated. After the initial assessment is completed, a nutrition plan should be created and implemented to address any issues identified. Weekly monitoring of the patient’s nutritional status should occur to determine if the nutritional intervention is having the desired effect. Monitoring should include the patient’s weight and assessment of functional status. The use of biochemical tests including serum prealbumin, transferrin, and nitrogen balance are also helpful.