Alternating-air and low-air-loss mattresses and overlays have little data to support their use for preventing or treating pressure ulcers, the Clinical Guidelines Committee of the American College of Physicians has concluded.
Many U.S. acute-care hospitals, home caregivers, and long-term nursing facilities use alternating-air and low-air-loss mattresses and overlays, even though the evidence in favor of using these surfaces is sparse and of poor quality, the guideline writers said.
The devices have not been show to actually reduce pressure ulcers. The harms have been poorly reported but could be significant. “Using these support systems is expensive and adds unnecessary burden on the health care system. Based on a review of the current evidence, lower-cost support surfaces should be the preferred approach to care,” Dr. Amir Qaseem, of the ACP, Philadelphia, and his associates wrote.
The committee performed an extensive review of the literature on pressure ulcers and compiled two Clinical Practice Guidelines – one concerning prevention (Ann. Intern. Med. 2015;162 [doi:10.7326/M14-1567]) and the other concerning treatment (Ann. Intern. Med. 2015;162 [doi:10.7326/M14-1568]) – in part because “a growing industry” has developed in recent years and aggressively pitches a wide array of products for this patient population. The guidelines present the available evidence on the comparative effectiveness of tools and strategies but state repeatedly that evidence regarding pressure ulcers is sparse and of poor quality.
The prevention guideline strongly recommends that clinicians choose advanced static mattresses or advanced static overlays rather than standard hospital mattresses for at-risk patients. Static mattresses and advanced static overlays provide a constant level of inflation or support and evenly distribute body weight. These products are among the few actually shown to reduce the incidence of pressure ulcers. They are also preferable to alternating-air mattresses and overlays, which change the distribution of pressure by inflating or deflating cells within the devices, and to low-air-loss mattresses and overlays, which use flowing air to regulate heat and humidity and adjust pressure.
Evidence is similarly poor or lacking concerning the use of other support surfaces such as heel supports or boots and a variety of wheelchair cushions. Also lacking evidence are other preventive interventions that extend beyond “usual care,” such as different types of repositioning schemes, a variety of leg elevations, various nutritional supplements, and a wide variety of skin care strategies and topical treatments.
The prevention guideline advises patient assessments to identify those at risk of developing pressure ulcers. However, there is not enough evidence to demonstrate that any one of the many risk assessment tools for this purpose is superior to the others, nor that any of these tools is superior to simple clinical judgment. Risk factors for pressure ulcers include older age; black race or Hispanic ethnicity; low body weight; cognitive impairment; physical impairments; and comorbid conditions that may affect soft-tissue integrity and healing, such as urinary or fecal incontinence, diabetes, edema, impaired microcirculation, hypoalbuminemia, and malnutrition, Dr. Qaseem and his associates wrote (Ann. Intern. Med. 2015 March 2 [doi:10.7326/M14-1567]).
The treatment guideline for patients who already have pressure ulcers similarly notes that the lack of evidence for advanced support surfaces such as alternating-air and low-air-loss mattresses and overlays. It similarly recommends advanced static mattresses or overlays for these patients.
The treatment guideline recommends protein or amino acid supplements as well as hydrocolloid or foam dressings to reduce wound size, and electrical stimulation to accelerate wound healing. The evidence for these recommendations is “weak” and of low- to moderate-quality, Dr. Qaseem and his associates said (Ann. Intern. Med. 2015 March 2 [doi:10.7326/M14-1568]). The evidence for the safety and efficacy of hyperbaric oxygen therapy, even though it is often used to treat pressure ulcers in hospitals, is similarly inconclusive. Also lacking good-quality evidence are the use of alternating-air chair cushions, three-dimensional polyester overlays, zinc supplements, L-carnosine supplements, wound dressings other than the ones already discussed, debriding enzymes, topical phenytoin, maggot therapy, biological agents other than platelet-derived growth factor, or hydrotherapy in which wounds are cleaned using a whirlpool or pulsed lavage.
