Beds, overlays and mattresses for preventing and treating pressure ulcers: an overview of Cochrane reviews and network meta-analysis

Dressings and topical agents for preventing pressure ulcers

BACKGROUND

Pressure ulcers occur when people cannot reposition themselves to relieve pressure over bony prominences. They are difficult to heal, costly, and reduce quality of life. Dressings and topical agents (lotions, creams, and oils) for pressure ulcer prevention are widely used. However, their effectiveness is unclear. This is the third update of this review.

OBJECTIVES

To evaluate the effects of dressings and topical agents on pressure ulcer prevention, in people of any age without existing pressure ulcers, but at risk of developing one, in any healthcare setting.

SEARCH METHODS

We used the Cochrane Wounds Specialised Register, CENTRAL, MEDLINE, two other databases, and two trial registers, together with reference checking, citation searching, and contact with study authors to identify the studies that are included in the review. The latest search date was November 2022. We imposed no restrictions on language, publication date, or setting.

SELECTION CRITERIA

We included randomised controlled trials that enroled people at risk of developing a pressure ulcer.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodological procedures.

MAIN RESULTS

In this update, we added 33 new studies, resulting in a total of 51 trials (13,303 participants). Of these, 31 studies involved dressings, 16 topical agents, and four included both dressings and topical agents. All trials reported the primary outcome of pressure ulcer incidence. Dressings Pressure ulcer incidence We made a total of 13 comparisons with 9027 participants. We present seven prioritised comparisons in the summary of findings (SoF) tables, as follows: silicone foam dressing versus no dressing (18 trials, 5903 participants; risk ratio (RR) 0.50, 95% confidence interval (CI) 0.33 to 0.77); foam dressing versus film dressing (3 trials, 569 participants; RR 0.72, 95% CI 0.20 to 2.67); hydrocellular foam dressing versus hydrocolloid dressing (1 trial, 80 participants; RR not estimable); silicone foam dressing type 1 versus silicone foam dressing type 2 (2 trials, 376 participants; RR 0.80, 95% CI 0.56 to 1.15); foam dressing versus fatty acid (2 trials, 300 participants; RR 1.67, 95% CI 0.49 to 5.72); polyurethane film versus hydrocolloid dressing (1 trial, 160 participants; RR 0.58, 95% CI 0.24 to 1.41); and hydrocolloid dressing versus no dressing (2 trials, 230 participants; RR 0.60, 95% CI 0.46 to 0.78). All low or very low-certainty evidence. The evidence is very uncertain about the effect of dressings on pressure ulcer development. Pressure ulcer stage Three comparisons reported pressure ulcer (PU) stage. Silicone foam dressing versus no dressing: PU stage 1 (8 trials, 1823 participants; RR 0.32, 95% CI 0.13 to 0.79); PU stage 2 (10 trials, 2873 participants; RR 0.47, 95% CI 0.30 to 0.73); PU stage 3 (3 trials, 718 participants; RR 0.45, 95% CI 0.06 to 3.21); PU stage 4 (2 trials, 610 participants; RR 0.21, 95% CI 0.02 to 1.77); unstageable PU (1 trial, 366 participants; RR 0.20, 95% CI 0.01 to 4.09); deep tissue injury (3 trials, 840 participants; RR 0.32, 95% CI 0.09 to 1.08). Foam dressing versus film dressing: PU stage 1 (1 trial, 270 participants; RR 0.56, 95% CI 0.39 to 0.80); PU stage 2 (1 trial, 270 participants; RR 1.00, 95% CI 0.06 to 15.82); deep tissue injury (1 trial, 270 participants; RR 0.67, 95% CI 0.11 to 3.93). Hydrocolloid dressing versus no dressing: PU stage 1 (1 trial, 108 participants; RR 0.54, 95% CI 0.31 to 0.94); PU stage 2 (1 trial, 108 participants; RR 0.86, 95% CI 0.28 to 2.66). All low or very low-certainty evidence. The evidence is very uncertain about the effect of dressings on different stages of pressure ulcer development. Adverse events One comparison reported adverse events: silicone foam dressing versus no dressing (3 trials, 2317 participants; RR not estimable; very low-certainty evidence). Silicone foam dressings may have little to no effect on the incidence of adverse events, but the evidence is very uncertain. Topical agents Pressure ulcer incidence We evaluated seven comparisons with 4276 participants. We present five prioritised comparisons in the SoF tables as follows: fatty acid versus placebo (6 trials, 2201 participants; RR 0.86, 95% CI 0.54 to 1.36); fatty acid versus usual care (7 trials, 1058 participants; RR 0.64, 95% CI 0.46 to 0.84); cream versus fatty acid (1 trial, 120 participants; RR 3.00, 95% CI 0.32 to 28.03); cream versus placebo (3 trials, 513 participants; RR 1.18, 95% CI 0.59 to 2.36); and cream versus usual care (1 trial, 47 participants; RR 1.60, 95% CI 0.84 to 3.04). All very low-certainty evidence. It is very uncertain whether they make any difference to PU development. Pressure ulcer stage Two comparisons reported PU stage. Fatty acid versus usual care: PU stage 1 (2 trials, 180 participants; RR 1.00, 95% CI 0.49 to 2.03); PU stage 2 (2 trials, 180 participants; RR 0.19, 95% CI 0.07 to 0.53). Cream versus placebo: PU stage 3 (1 trial, 258 participants; RR 1.25, 95% CI 0.34 to 4.55); PU stage 4 (1 trial, 258 participants; RR 0.33, 95% CI 0.01 to 8.11). Both low or very low-certainty evidence. It is uncertain whether they make any difference to the stage of PU development. Adverse events One comparison reported adverse events: fatty acid versus placebo (3 trials, 967 participants; RR 4.38, 95% CI 0.50 to 38.30; very low-certainty evidence). Fatty acid may have little to no effect on the incidence of adverse events compared to placebo, but the evidence is very uncertain. Risk of bias and imprecision were the main reasons for downgrading the certainty of the evidence.

AUTHORS' CONCLUSIONS

The included studies tested a wide variety of dressings and topical agents. The evidence for all interventions is uncertain or very uncertain; thus, it is unclear whether any of the dressings or topical agents studied make any difference to pressure ulcer development. Future studies should engage with stakeholders to determine priority interventions.

Beds, overlays and mattresses for preventing and treating pressure ulcers: an overview of Cochrane Reviews and network meta-analysis

BACKGROUND

Pressure ulcers (also known as pressure injuries, pressure sores and bed sores) are localised injuries to the skin or underlying soft tissue, or both, caused by unrelieved pressure, shear or friction. Specific kinds of beds, overlays and mattresses are widely used with the aim of preventing and treating pressure ulcers.

OBJECTIVES

To summarise evidence from Cochrane Reviews that assess the effects of beds, overlays and mattresses on reducing the incidence of pressure ulcers and on increasing pressure ulcer healing in any setting and population. To assess the relative effects of different types of beds, overlays and mattresses for reducing the incidence of pressure ulcers and increasing pressure ulcer healing in any setting and population. To cumulatively rank the different treatment options of beds, overlays and mattresses in order of their effectiveness in pressure ulcer prevention and treatment.

METHODS

In July 2020, we searched the Cochrane Library. Cochrane Reviews reporting the effectiveness of beds, mattresses or overlays for preventing or treating pressure ulcers were eligible for inclusion in this overview. Two review authors independently screened search results and undertook data extraction and risk of bias assessment using the ROBIS tool. We summarised the reported evidence in an overview of reviews. Where possible, we included the randomised controlled trials from each included review in network meta-analyses. We assessed the relative effectiveness of beds, overlays and mattresses for preventing or treating pressure ulcers and their probabilities of being, comparably, the most effective treatment. We assessed the certainty of the evidence using the GRADE approach.

MAIN RESULTS

We include six Cochrane Reviews in this overview of reviews, all at low or unclear risk of bias. Pressure ulcer prevention: four reviews (of 68 studies with 18,174 participants) report direct evidence for 27 pairwise comparisons between 12 types of support surface on the following outcomes: pressure ulcer incidence, time to pressure ulcer incidence, patient comfort response, adverse event rates, health-related quality of life, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Pressure ulcer incidence: our overview includes direct evidence for 27 comparisons that mostly (19/27) have very low-certainty evidence concerning reduction of pressure ulcer risk. We included 40 studies (12,517 participants; 1298 participants with new ulcers) in a network meta-analysis involving 13 types of intervention. Data informing the network are sparse and this, together with the high risk of bias in most studies informing the network, means most network contrasts (64/78) yield evidence of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces (e.g. static air overlays) (risk ratio (RR) 0.46, 95% confidence interval (CI) 0.29 to 0.75), alternating pressure (active) air surfaces (e.g. alternating pressure air mattresses, large-celled ripple mattresses) (RR 0.63, 95% CI 0.42 to 0.93), and reactive gel surfaces (e.g. gel pads used on operating tables) (RR 0.47, 95% CI 0.22 to 1.01) may reduce pressure ulcer incidence. The ranking of treatments in terms of effectiveness is also of very low certainty for all interventions. It is unclear which treatment is best for preventing ulceration. (2) Time to pressure ulcer incidence: four reviews had direct evidence on this outcome for seven comparisons. We included 10 studies (7211 participants; 699 participants with new ulcers) evaluating six interventions in a network meta-analysis. Again, data from most network contrasts (13/15) are of very low certainty. There is low-certainty evidence that, compared with foam surfaces (reference treatment), reactive air surfaces may reduce the hazard of developing new pressure ulcers (hazard ratio (HR) 0.20, 95% CI 0.04 to 1.05). The ranking of all support surfaces for preventing pressure ulcers in terms of time to healing is uncertain. (3) Cost-effectiveness: this overview includes direct evidence for three comparisons. For preventing pressure ulcers, alternating pressure air surfaces are probably more cost-effective than foam surfaces (moderate-certainty evidence). Pressure ulcer treatment: two reviews (of 12 studies with 972 participants) report direct evidence for five comparisons on: complete pressure ulcer healing, time to complete pressure ulcer healing, patient comfort response, adverse event rates, and cost-effectiveness. Here we focus on outcomes with some evidence at a minimum of low certainty. (1) Complete pressure ulcer healing: our overview includes direct evidence for five comparisons. There is uncertainty about the relative effects of beds, overlays and mattresses on ulcer healing. The corresponding network meta-analysis (with four studies, 397 participants) had only three direct contrasts and a total of six network contrasts. Again, most network contrasts (5/6) have very low-certainty evidence. There was low-certainty evidence that more people with pressure ulcers may heal completely using reactive air surfaces than using foam surfaces (RR 1.32, 95% CI 0.96 to 1.80). We are uncertain which surfaces have the highest probability of being the most effective (all very low-certainty evidence). (2) Time to complete pressure ulcer healing: this overview includes direct evidence for one comparison: people using reactive air surfaces may be more likely to have healed pressure ulcers compared with those using foam surfaces in long-term care settings (HR 2.66, 95% CI 1.34 to 5.17; low-certainty evidence). (3) Cost-effectiveness: this overview includes direct evidence for one comparison: compared with foam surfaces, reactive air surfaces may cost an extra 26 US dollars for every ulcer-free day in the first year of use in long-term care settings (low-certainty evidence).

AUTHORS' CONCLUSIONS

Compared with foam surfaces, reactive air surfaces may reduce pressure ulcer risk and may increase complete ulcer healing. Compared with foam surfaces, alternating pressure air surfaces may reduce pressure ulcer risk and are probably more cost-effective in preventing pressure ulcers. Compared with foam surfaces, reactive gel surfaces may reduce pressure ulcer risk, particularly for people in operating rooms and long-term care settings. There are uncertainties for the relative effectiveness of other support surfaces for preventing and treating pressure ulcers, and their efficacy ranking. More high-quality research is required; for example, for the comparison of reactive air surfaces with alternating pressure air surfaces. Future studies should consider time-to-event outcomes and be designed to minimise any risk of bias.