Hospital bed mattress overlay / dynamic air / anti-decubitus / tube Multi-mode Mattress Replacement and Mattress Overlay Systems for 24 hour pressure redistribution The Auto Logic® 200 and 175 Mattress Replacement Systems and the Auto Logic® 110 Mattress Overlay System provide automatic, self-setting therapy options with the benefit of a battery-powered active transportation function. The Auto Logic range is recommended for round-the-clock pressure ulcer prevention and management of all stages in combination with a resident/patient specific monitoring, repositioning and wound care programme. The Auto Logic pump uses Self Set Technology (SST) to regularly assess the resident's/patient's body mass distribution and readjusts cell air pressures to meet their specific needs ensuring optimum pressure area management.K Vanderwee, M Grypdonck, and T Defloor.Link to full article: [Journal publisher]CRD summaryThe authors concluded that alternating pressure air mattresses were likely to be more effective than standard hospital mattresses, but no conclusions could be reached about their comfort and further research was required.
The authors’ conclusions appeared to reflect the evidence, but incomplete reporting of review methods and any differences between studies made it difficult to assess their reliability. Authors' objectivesTo examine studies evaluating alternating pressure air mattresses for the prevention of pressure ulcers.SearchingPubMed/MEDLINE, CINAHL, EMBASE and Cochrane Central Register of Controlled Trials were searched from 1980 to September 2006 for studies published in English, German, French or Dutch. Search terms were reported. In addition, reference lists of retrieved articles were screened. Study selectionStudies of any design that compared alternating pressure air mattresses (APAMs) with other mattresses or other types of alternating pressure air mattresses for the prevention of pressure ulcers were eligible for inclusion. In the review, alternating pressure air mattresses were defined as alternating pressure air replacements (APARs) and alternating pressure air overlays (APAOs). The review assessed effectiveness, contact interface pressure and blood perfusion, comfort, mechanical reliability and costs.
Randomised controlled trials in a variety of patients (at-risk, surgical, long-term care elderly, geriatric, chronic medical conditions, orthopaedic and intensive care unit) and experimental laboratory studies in predominantly healthy people were included. Studies compared different types of alternating pressure air mattresses with each other and with a variety of other types of mattresses (including air, water, foam, gel, hollow fibre, constant low-pressure and standard hospital mattresses). Studies used the following methods to assess effectiveness: the incidence of pressure ulcers; contact interface pressure (CIP); and blood perfusion, as measured by transcutaneous oxygen (tcPO2) and transcutaneous carbon dioxide (tcPCO2). Comfort was generally assessed using non-validated questionnaires or visual analogue scales. Where reported, the duration of follow-up among randomised controlled trials assessing effectiveness ranged from one week to three months. Two reviewers independently selected studies.
Assessment of study qualityThe validity of randomised controlled trials was assessed using power calculation, reporting of randomisation method and baseline comparability of treatment groups. Other methodological limitations assessed included drop-outs and unit of analysis. The authors did not state how the validity assessment was performed.Data extractionThe authors stated neither how data were extracted for the review nor how many reviewers performed the data extraction. For each study, results data for the main outcomes were reported with some indication of the level of statistical significance.Methods of synthesisThe studies were grouped by outcome and study design and combined in a narrative synthesis. Data were presented in tables.Results of the reviewThirty-five studies were reported in the review: 20 randomised controlled trials (n= approximately 4,526); 13 experimental studies (n=258); and one retrospective study. Sample size ranged from 10 to 1,971 patients.Study quality: 18 randomised controlled trials either had insufficient power or did not estimate the required sample size;
11 randomised controlled trials had unclear or inadequate randomisation; and four randomised controlled trials did not report baseline comparability of treatment groups. The sample size of laboratory studies was small (10 to 57) and nine such studies involved only healthy people. Randomised controlled trials assessing effectiveness (15 randomised controlled trials, n=4,366)One randomised controlled trial (n=600) reported a significantly lower incidence of pressure ulcers associated with alternating pressure air overlays compared to a standard hospital mattress (4.2 per cent versus 13 per cent, p<0.01). Seven of 10 studies reported no significant difference between alternating pressure air overlays or alternating pressure air replacements and different types of constant low-pressure mattresses; three randomised controlled trials reported that alternating pressure air overlays or alternating pressure air replacements were significantly more effective than constant low-pressure mattresses.
Four randomised controlled trials compared different types of alternating pressure air mattresses (results were reported). One retrospective study reported that alternating pressure air replacements were more effective than standard hospital mattresses in reducing pressure ulcer in burns patients.Experimental studies assessing contact interface pressure and blood perfusion (13 studies, n=258)Two studies compared alternating pressure air mattresses versus standard hospital mattress; one reported significantly lower contact interface pressure with the alternating pressure air overlays and the other reported significantly higher tcPO2 with the alternating pressure air overlays. Four studies compared alternating pressure air mattresses with different constant low-pressure surfaces and seven studies compared different types of alternating pressure air mattresses; Comfort: Four randomised controlled trials compared alternating pressure air mattresses with constant low-pressure mattresses. Studies variously reported problems with hardness and noise (one study), few problems with either mattress (one study), no significant difference in comfort scores (one study) and more problems with alternating pressure air overlays compared to alternating pressure air replacements (one study).
The authors stated that findings on comfort were inconsistent due to different types of mattresses used and outcomes reported. Results from other laboratory studies and randomised controlled trials that compared different types of alternating pressure air overlays were also reported. Mechanical reliability and user errors were also reported in the review. Cost information One cost-effectiveness study reported that alternating pressure air overlays were more cost-effective than standard hospital mattresses for the prevention of pressure sores. Other studies reported increased costs with alternating pressure air overlays compared with hollow fibre mattresses (54 per cent increase in one study) and lower costs with alternating pressure air replacements, mainly due to reduced length of stay and delayed development of pressure sores (one study).Authors' conclusionsAlternating pressure air mattresses were likely to be more effective than standard hospital mattresses, but no conclusions could be reached about their comfort.
Further research was required. Implications of the review for practice and researchPractice: The authors stated that health organisations must ensure that nurses were trained in the correct use of different alternating pressure air mattresses. The authors were unable to make recommendations for clinical practice about the efficacy of different alternating pressure air mattresses or alternating pressure air mattresses compared to constant low-pressure mattresses.Research: The authors stated that large high-quality randomised controlled trials were required to evaluate the effectiveness of alternating pressure air mattresses. There was a need to design and validate more appropriate measures of comfort. Bibliographic detailsVanderwee K, Grypdonck M, Defloor T. Alternating pressure air mattresses as prevention for pressure ulcers: a literature review. International Journal of Nursing Studies 2008; Other publications of related interestCullum N, McInnes E, Beller-Syer SEM, Legood R (2006). Surface support for pressure ulcer prevention (cochrane review).