Beds, mattresses and cushions for pressure sore prevention and treatment

Abstract

Background Pressure sores affect people who are unable to change position regularly. Sustained pressure on those areas which support the body leads to reduced blood supply and eventually death of the skin and underlying muscles (a pressure sore). There are two main approaches to preventing these sores; (1) use of a conforming support surface to distribute the body weight over a large area; (2) use of an alternating support surface where inflatable cells alternately inflate and deflate. Treatment of pressure sores also requires reduction of pressures at the damaged area of skin. Special support surfaces, aimed at pressure redistribution, including beds, mattresses and cushions, are widely used and range. It is unclear to what extent these surfaces can prevent or treat pressure sores and whether any system is better than any other. Objectives To assess the effectiveness of pressure relieving beds, mattresses and cushions (support surfaces) in the prevention and treatment of pressure sores. Search strategy Searches of 19 databases, hand searching of journals, conference proceedings, and bibliographies. Selection criteria Randomised controlled trials evaluating support surfaces for the prevention or treatment of pressure sores. There was no restriction on articles based on language or publication status. Data collection and analysis Data extraction and assessment of study quality were undertaken by two reviewers independently. Trials with similar patients, comparisons, and outcomes were pooled. Where pooling was inappropriate, trials are discussed in a narrative review. Main results Prevention: Twenty nine RCTs of support surfaces for pressure sore prevention were identified. Some high specification foam mattresses were more effective than 'standard' hospital foam mattresses in moderate-high risk patients. Pressure relieving mattresses in the operating theatre reduced the incidence of pressure sores post-operatively. The relative merits of alternating and constant low pressure, and of the different alternating pressure devices are unclear. Seat cushions and simple, constant low-pressure devices have not been adequately evaluated. Limited evidence suggests that low air loss beds reduce the incidence of pressure sores in intensive care. Treatment: Six RCTs of support surfaces for pressure sore treatment were identified. There is good evidence that air-fluidised and low air loss beds improve healing rates. Seat cushions have not been adequately evaluated. Two RCTs evaluated surfaces for both prevention and treatment in the same trial. Reviewers' conclusions Prevention - There is good evidence of the effectiveness of high specification foam over standard hospital foam, and pressure relief in the operating theatre. Treatment - There is good evidence of the effectiveness of air-fluidised and low air loss devices as treatments. Overall, however, it is impossible to determine the most effective surface for either prevention or treatment.