Pressure-relieving Mattress Research Articles

Effectiveness of a grid mattress on adults' sleep quality and health: A quasi-experimental intervention study.

Despite that 93% of people indicate that a mattress plays a pivotal role in achieving high-quality sleep, there is a scarcity of research investigating the influence of mattresses on sleep quality, pain, and mood in nonclinical poor sleepers. The purpose was to examine the effectiveness of a pressure-releasing medium-firm grid mattress on sleep and health outcomes (e.g., mood, pain, daytime fatigue) of adults with nonclinical insomnia symptoms using a quasi-experimental design. Participants were 39 adults (mean age = 45.29) with nonclinical insomnia (i.e., occasional sleeplessness). Following 1 week of baseline assessments on their current mattress, they slept on a pressure-relieving grid mattress for 8 weeks. Participants completed self-report assessments of the Pittsburgh Sleep Quality Index, Berlin Questionnaire, Insomnia Severity Index, Restorative Sleep Questionnaire, Perceived Stress Scale, Profile of Mood States, Daytime Fatigue Scale, Pain and Sleep Questionnaire, and Brief Pain Inventory at Baseline and Weeks 1, 2, 3, 4, and 8. Participants continually wore an Oura Ring to objectively assess sleep and daytime activity. The data were collected from January 2022 to April 2022 and were stored electronically. Repeated-measures analyses of variance were used to analyze mean time differences. Self-reported sleep quality, perceived pain, perceived stress, mood, and daytime fatigue improved significantly from Baseline to Week 8, p's < 0.05. Objective Oura Ring validated the self-reported sleep and daytime activity outcomes with improvements in sleep duration, time awake during the night, light sleep, deep sleep, and total sleep time, p's < 0.05. No significant time effects were evidenced for rapid eye movement sleep. No adverse events were reported. The grid mattress is a simple, noninvasive, and nonpharmacological intervention that improved adults sleep quality and health. Controlled trials are encouraged to examine the effects of this mattress in a variety of populations and environments.

Novel Support Surface To Alleviate Pressure Ulcer Formation During The Rehabilitation Of Immobile Patients: A Preliminary Investigation

<h3>Research Objectives</h3> To investigate the effectiveness and tolerability of a novel support surface on immobile patients during rehabilitation. <h3>Design</h3> Before-after trial. <h3>Setting</h3> Inpatient tertiary rehabilitation. <h3>Participants</h3> 5 patients with spinal cord injuries and very limited mobility participated in the study. <h3>Interventions</h3> A novel support surface was fabricated. It can dynamically redistribute pressures to less that the critical closing pressure of 10kPa, above which the risk of development of pressure ulcers is high. Each trial lasts 10 days and comprises of 5 phases. Phases 1 and 2A last 2 hours each and the rest of the phases last 3 days each. 1: Use of standard care pressure-relieving mattress and 2-hourly turning 2A: Familiarisation with the the prototype 2B: 2-hourly turning on the prototype 3: 3-hourly turning on the prototype 4: 4-hourly turning on the prototype The pressures over bony prominences (sacrum) was recorded in real time and the pressure-time area under curve (PTAUC) calculated. <h3>Main Outcome Measures</h3> Comfort level (11-point visual analogue scale) Presence of pressure injury Maximum pressure exerted PTAUC. <h3>Results</h3> The average age of these patients is 51.6 years. 1 patient did not complete the study as he developed a skin tear which, after investigation, was deemed un-related to the support surface as it was not a typical area for pressure injury. The average comfort level was 8.3. None of the patients developed pressure injuries. The maximum pressures exerted was than 10kPa and PTAUC was kept less than 20kPa-hour even when the turning frequency is stretched to every 4 hours. <h3>Conclusions</h3> This novel support surface can potentially be used during the rehabilitation phase of immobile patients to allow 4-hourly turning so as to reduce the patient disturbance and the manpower required for regular turning. <h3>Author(s) Disclosures</h3> Nil.

Effects of posture and firmness on cough strength in a pressure-relieving air mattress

Effects of posture and firmness on cough strength in a pressure-relieving air mattress

Posture and firmness changes in a pressure-relieving air mattress affect cough strength in elderly people with dysphagia.

Dysphagia is the major pathophysiologic mechanism leading to aspiration pneumonia in the elderly. Elderly people with dysphagia who show low levels of the cough peak flow (CPF) are at greater risk for aspiration pneumonia. It has been reported that CPF values were significantly lower in the “soft” versus “hard” mode of a pressure-relieving air mattress in healthy volunteers in a supine position. Parameters such as spinal curvature, however, were not evaluated in detail. In this study, we clarified whether the changes in posture associated with two different firmness levels of a pressure-relieving air mattress were associated with cough production and related factors in the elderly with dysphagia. The body sinking distance, pelvic tilt angle, and immersion of the lumbar spine were measured to evaluate changes in posture. Forty subjects met the study criteria for dysphagia. The “soft” mode showed significantly lower CPF values than the “hard” mode (soft 274.9 ± 107.2 L/min vs. hard 325.0 ± 99.5 L/min, MD 50.0 95%CI 33.1–66.9 P < 0.001). Values of forced vital capacity (FVC) and maximal inspiratory pressure (PImax) were significantly lower in the “soft” mode than in the “hard” mode (MD 0.10 95%CI 0.04–0.17, P = 0.002, MD 3.2 95%CI 0.9–5.5, P = 0.007, respectively). Although there was no significant difference between the two firmness levels, maximal expiratory pressure (PEmax) values also tended to be lower in the “soft” than in the “hard” mode, (MD 2.9 95%CI -0.6–6.3 P = 0.1). At both firmness levels, CPF values were significantly correlated with FVC, PImax, and PEmax. The difference in sinking distance in the anterior superior iliac spine was significantly larger than that in the lesser tubercle of the humerus and patella. Additionally, in the soft mode, the pelvic tilt angle and contact area around the lumbar spine were significantly larger than those observed in the “hard” mode. Parameters associated with the production of cough, including inspiratory muscle strength, lung volume, and ultimately CPF, may be affected by immersion of the lumbar spine and curvature of the spine that results from the “soft” mode in elderly patients with dysphagia.

Under pressure: relieving ulcers with mattresses

Pressure ulcers are a common occurence in the care home population, but much can be done to prevent and treat these. Drew Payne discusses the most efficient ways of selecting and using pressure-relieving mattresses and cushions

Effectiveness of a pressure-relieving mattress in an acute stroke ward.

Between the 10 May and 18 July 2016, St Helens and Knowsley Teaching Hospitals NHS Trust conducted a small, non-controlled evaluation set out to assess the performance of the Apex Pro-care Auto pressure-relieving mattress in an acute stroke ward. Seven patients, assessed as being at medium-to-high risk of developing a pressure ulcer (PU), were recruited into the evaluation; the mean age was 73.1 years. Three patients were bed bound and four had restricted mobility. The average length of time spent on the mattress was 31 days. At the end of the evaluation, none of the patients had developed a PU while using the mattress. These results indicate that, when combined with a robust PU prevention plan inclusive of repositioning, this pressure-relieving mattress is effective in preventing pressure ulceration.

Strategies to support prevention, identification and management of pressure ulcers in the community.

Pressure ulcers are classified as serious incidents, cause pain and distress, and are a source of infection. Unlike patients in hospital, those in the community spend only a small amount of time with healthcare practitioners, so strategies are required to ensure they remain protected against pressure damage when community nurses are not with them. A risk assessment should be carried out to outline a patient's risks and used to develop a strategy for that person. Patients have different risks so prevention strategies need to be tailored individually. Strategies, which cover issues such as pressure-relieving equipment, mattress type, mobility aids and nutrition, should be monitored to ensure they continue to meet patients' needs, as their health, carers and other matters may change. Patients and their carers may need education on ulcers, including on myths, as it is essential they are involved.

Predictors of pressure injury prevention strategies in at-risk medical patients: An Australian multi-centre study

Summary Background Pressure injuries impact both patients and healthcare organisations. Implementing pressure injury prevention strategies reflects current clinical practice guidelines, but in Australia, evidence on the factors that predict the implementation of these strategies is lacking. Aim To determine the patient, clinical and contextual factors that predict the implementation of pressure injury prevention strategies among acute medical patients with reduced mobility at two Australian hospitals. Method An observational study using chart audits and semi-structured observations. A consecutive sample of 241 participants (patients) was recruited from four medical units at two large Australian hospitals. Multiple logistic regression and multiple regression analyses were performed to identify predictors of support surfaces, regular repositioning, patient education and the number of pressure injury prevention strategies. Results Only 113 (46.9%) participants had a pressure injury risk assessment undertaken on admission. Regular repositioning was the most frequent, and often the only implemented strategy. Two factors predicted the implementation of support surfaces: participants identified at pressure injury risk during hospitalisation, and their 24-h activity. As a participant's mobility decreased, there was a 6% increase in the implementation of support surfaces ( p =0.001) such as pressure-relieving mattresses. Participants identified at pressure injury risk were more likely to receive prevention education. Conclusion Participants identified at pressure injury risk were most likely to receive prevention strategies. The low-pressure injury risk assessment rates mean some patients may not receive the recommended preventive care. There seems to be a reliance on a single prevention strategy, rather than a suite of them.

Effects of different heel angles in sleep mode on heel interface pressure in the elderly

BackgroundThe heels are one of the most common sites of pressure ulcers, and the incidence rate in the elderly aged 70years or older is high. Although there is literature on heel interface pressure, the heel interface pressure of the elderly in different postures has not yet been explored, which will be investigated in this study, as well as the effects of different foot positions. Their skin conditions will also be examined. MethodsTwenty-five females and twenty-six males, 70years old or older, are evaluated while lying down, with only their naked foot in its natural position on a mattress, as well as placed on a standard or pressure-relieving mattress in different positions. The moisture, sebum content, and elasticity of the skin of the heel are tested. FindingsThe heel of most of the participants is positioned at a 60°–69° or 90°–99° angle to the support surface. The heel interface pressure is the greatest when the foot is upright. The age, weight, and body mass index have no significant impacts. The moisture and sebum content are extremely low while elasticity is normal. InterpretationThe relaxed position of the foot is in neutral external rotation and upright positions. A greater amount of pressure is experienced when the foot is upright. The pressure-relieving mattress is more effective for reducing heel pressure but may not apply to all cases. Finally, the skin of the heel is dry and lacks sebum, which implies greater risk of developing heel sores.

Manual versus Mechanical Chest Compressions on Surfaces of Varying Softness with or without Backboards: A Randomized, Crossover Manikin Study

BackgroundChest compression quality is decisive for overall outcome after cardiac arrest. Chest compression depth may decrease when cardiopulmonary resuscitation (CPR) is performed on a mattress, and the use of a backboard does not necessarily improve compression depth. Mechanical chest compression devices may overcome this problem. ObjectivesWe sought to investigate the effectiveness of manual chest compressions both with and without a backboard compared to mechanical CPR performed on surfaces of different softness. MethodsTwenty-four advanced life support (ALS)–certified rescuers were enrolled. LUCAS2 (Physio-Control, Redmond, WA) delivers 52 ± 2 mm deep chest compressions and active decompressions back to the neutral position (frequency 102 min−1; duty cycle, 50%). This simulated CPR scenario was performed on a Resusci-Anne manikin (Laerdal, Stavanger, Norway) that was lying on 3 different surfaces: 1) a concrete floor, 2) a firm standard mattress, and 3) a pressure-relieving mattress. Data were recorded by the Laerdal Skill Reporting System. ResultsManual chest compression with or without a backboard were performed correctly less often than mechanical chest compressions (floor: 33% [interquartile range {IQR}, 27–48%] vs. 90% [IQR, 86–94%], p < 0.001; standard mattress: 32% [IQR, 20–45%] vs. 27% [IQR, 14–46%] vs. 91% [IQR, 51–94%], p < 0.001; and pressure-relieving mattress 29% [IQR, 17–49%] vs. 30% [IQR, 17–52%] vs. 91% [IQR, 87–95%], p < 0.001). The mean compression depth on both mattresses was deeper with mechanical chest compressions (floor: 53 mm [range, 47–57 mm] vs. 56 mm [range, 54–57 mm], p = 0.003; standard mattress: 50 mm [range, 44–55 mm] vs. 51 mm [range, 47–55 mm] vs. 55 mm [range, 54–58 mm], p < 0.001; and pressure-relieving mattress: 49 mm [range, 44–55 mm] vs. 50 mm [range, 44–53 mm] vs. 55 mm [range, 55–56 mm], p < 0.001). In this ∼6-min scenario, the mean hands-off time was ∼15 to 20 s shorter in the manual CPR scenarios. ConclusionsIn this experimental study, only ∼30% of manual chest compressions were performed correctly compared to ∼90% of mechanical chest compressions, regardless of the underlying surface. Backboard use did not influence the mean compression depth during manual CPR. Chest compressions were deeper with mechanical CPR. The mean hands-off time was shorter with manual CPR.

Support surfaces for pressure ulcer prevention.

Pressure ulcers (i.e. bedsores, pressure sores, pressure injuries, decubitus ulcers) are areas of localised damage to the skin and underlying tissue.They are common in the elderly and immobile, and costly in financial and human terms. Pressure-relieving support surfaces (i.e. beds, mattresses, seat cushions etc) are used to help prevent ulcer development. This systematic review seeks to establish:(1) the extent to which pressure-relieving support surfaces reduce the incidence of pressure ulcers compared with standard support surfaces, and,(2) their comparative effectiveness in ulcer prevention. In April 2015, for this fourth update we searched The Cochrane Wounds Group Specialised Register (searched 15 April 2015) which includes the results of regular searches of MEDLINE, EMBASE and CINAHL and The Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 3). Randomised controlled trials (RCTs) and quasi-randomised trials, published or unpublished, that assessed the effects of any support surface for prevention of pressure ulcers, in any patient group or setting which measured pressure ulcer incidence. Trials reporting only proxy outcomes (e.g. interface pressure) were excluded. Two review authors independently selected trials. Data were extracted by one review author and checked by another.Where appropriate, estimates from similar trials were pooled for meta-analysis. For this fourth update six new trials were included, bringing the total of included trials to 59.Foam alternatives to standard hospital foam mattresses reduce the incidence of pressure ulcers in people at risk (RR 0.40 95% CI 0.21 to 0.74).The relative merits of alternating- and constant low-pressure devices are unclear. One high-quality trial suggested that alternating-pressure mattresses may be more cost effective than alternating-pressure overlays in a UK context.Pressure-relieving overlays on the operating table reduce postoperative pressure ulcer incidence, although two trials indicated that foam overlays caused adverse skin changes. Meta-analysis of three trials suggest that Australian standard medical sheepskins prevent pressure ulcers (RR 0.56 95% CI 0.32 to 0.97). People at high risk of developing pressure ulcers should use higher-specification foam mattresses rather than standard hospital foam mattresses. The relative merits of higher-specification constant low-pressure and alternating-pressure support surfaces for preventing pressure ulcers are unclear, but alternating-pressure mattresses may be more cost effective than alternating-pressure overlays in a UK context. Medical grade sheepskins are associated with a decrease in pressure ulcer development. Organisations might consider the use of some forms of pressure relief for high risk patients in the operating theatre.

Evaluating an alternating mattress on an elderly rehabilitation ward.

Pressure ulcer prevention is a primary requirement for the NHS. Robust nursing procedures and the provision of pressure-relieving equipment is vital in meeting this requirement. However, the Department of Health also regards making considerable financial savings as a fundamental requirement. There is a firm clinical consensus among national and international bodies that patients at a high risk of developing pressure ulcers, or with existing tissue damage, should be cared for on an alternating (pressure-relieving) mattress system. This evaluation process looks at the performance of the lower cost Air-Flo(®) 8 Acute alternating (pressure-relieving) mattress system to see if it is effective in meeting the needs of patients. The outcomes suggest that when combined with a pressure ulcer management plan and turning schedule the Air-Flo(®) 8 Acute performed well, giving an option to continue to care for high-risk patients with an empirically proven effective therapy, while making considerable financial savings.

Improving outcomes for patients with proximal femoral fractures.

A peri-operative bay was created to treat all patients with proximal femoral fractures admitted to one trauma ward at the Queen's Medical Centre, Nottingham. All patients had urinary catheterisation and their fluid intake and output was recorded; patients had daily blood tests and were cared for on pressure-relieving mattresses. In addition, a study day was provided for all nursing staff on the management of patients with proximal femoral fractures. These measures resulted in a significant decrease in the incidence of acute kidney injury, reduced the length of hospital stay for patients on this ward and reduced the numbers of falls and pressure-related injuries for these patients.

Evaluation of an individual sleep intervention programme in people undergoing peritoneal dialysis treatment

This study aimed to evaluate effects of a non-pharmacological intervention on sleep, activity and fatigue in patients receiving peritoneal dialysis by the use of both actigraphy registration and self-assessed questionnaires. Insomnia is estimated to affect up to 60% of haemo- and peritoneal dialysis patients. It is associated with two common uremic symptoms, pruritus and restless legs syndrome. To our knowledge, no interventions have been evaluated by actigraphy. A prospective multiple baseline single-case experimental design. Two women and seven men with sleep problems, 48-77 years, treated with PD participated in a 17-week study from January 2009 to February 2011. Two interventions were separately implemented. First, a pressure-relieving mattress and second, a four week individual sleep hygiene and sleep scheduling intervention. The two interventions were evaluated both objectively by actigraphy and subjectively by questionnaires. A total of 315 sleep-wake cycles from nine individuals were evaluated. Three patients improved clinically significantly in five or more of the nine outcomes, i.e. sleep onset latency, nocturnal sleep duration, numbers and duration of napping, movement and fragmentation index, number of steps, metabolic equivalent unit, sleep efficiency and fatigue. The other six patients also showed improvements but to a lesser degree. Physical activity advice was the intervention that yielded most sleep improvements. This study illuminates the need for regular assessment of sleep and tiredness. It also demonstrates how a non-pharmacological treatment and self-management can be applied with renal supportive care to improve sleep quality. This study is a clinical example of a non-pharmacological intervention with supportive care and self-management. This model can improve health and reduce the pharmacological burden because hypnotics can be replaced by sleep hygiene self-care activities.

Prevalence and incidence of pressure ulcers in Japanese long-term-care hospitals

In Japan, long-term-care hospitals and facilities face the problem of quality of care, and providing adequate pressure ulcer care is one of the most urgent quality issues. Purpose of the present study was to explore the prevalence and incidence of pressure ulcers in long-term-care hospitals in Japan, and to identify factors associated with them. An anonymous questionnaire was sent to 720 randomly sampled, long-term-care hospitals all over Japan. The prevalence and incidence of pressure ulcers and their factors, including organizational strategies for pressure ulcer prevention and management, were examined. The mean prevalence and incidence of pressure ulcers was 9.6 and 1.9% per month, respectively. Almost all hospitals had established an interdisciplinary team for pressure ulcer prevention, developed a clinical protocol for pressure ulcers, and implemented education for staff. However, 35% of the interdisciplinary teams were not useful, more than half of the clinical protocols were not used frequently, and about half of the wards did not have sufficient pressure-relieving mattresses. In multiple regression analyses, a low prevalence of pressure ulcers was associated with a lower ratio of clients with a high medical severity level (p=0.034), the use of a clinical protocol including the management of preventive devices (p=0.023), the standardized pressure ulcer assessment tool (DESIGN-R; p=0.017), and staff education (p=0.003). This study demonstrated a higher prevalence and incidence of pressure ulcers in long-term-care hospitals in Japan as compared to regular acute-care hospitals, as well as poor organizational strategies for managing pressure ulcers.

Achieving effective outcomes: monitoring the effectiveness of the Softform Premier Active (TM) mattress

The identification of pressure-relieving mattresses to achieve positive clinical outcomes for patients and financial considerations for organizations is a challenge for health-care staff. This article reports on an audit undertaken within a primary care trust to determine the clinical and cost effectiveness of the Softform® Premier Active mattress. Preliminary results have been previously published (Stephen-Haynes, 2009) and are presented here in full.

Pressure sores in spinal cord injury: Active intervention saves costs

�ARTICLE Summary. Pressure sores are a predictable consequence of poorly managed spinal cord-injured patients. Not only do pressure sores contribute to the morbidity, but also add significantly to the medical/nursing management, cost and admission stay, limiting optimal bed utilisation. This intervention study assesses the impact of active intervention in terms of pressure-relief mattresses, establishment of a ‘turning team’ and medical/nursing staff education on pressure sore incidence, extended stay and associated costs. Results. The de novo incidence reduced from 16% to nil once the interventions were in place, with an annualised estimated saving of R738 239, or R4 732 per cervical spine-injured patient admitted. Conclusion. Active intervention costs are well justified by the cost saving in terms of reduced extended stay days. The routine use of pressure-relieving mattresses and a turning team in the management of spinal cord injuries is recommended.

Best practices for elderly hip fracture patients

To determine evidence-based best practices for elderly hip fracture patients from the time of hospital admission to 6 months postfracture. MEDLINE, Cochrane Library, CINAHL, Embase, PEDro, Ageline, NARIC, and CIRRIE databases were searched for potentially eligible articles published between 1985 and 2004. Two independent reviewers determined studies appropriate for inclusion using standardized selection criteria, extracted data, evaluated internal validity, and then rated studies according to levels of evidence. Only Level 1 or 2 evidence was included in our summary of clinical recommendations. Spinal anesthesia, pressure-relieving mattresses, perioperative antibiotics, and deep vein thromboses prophylaxes had consistent evidence of benefit. Routine preoperative traction was not associated with any benefits and should be abandoned. Types of surgical management, postoperative wound drainage, and even "multidisciplinary" care, lacked sufficient evidence to determine either benefit or harm. There was little evidence to either determine best subacute rehabilitation practices or to direct ongoing medical issues (e.g., nutrition). Studies conducted during the subacute recovery period were heterogeneous in terms of treatment settings, interventions, and outcomes studied and had no clear evidence for best treatment practices. The evidence for perioperative practices is relatively robust and evidence-based perioperative treatment guidelines can be easily established. Conversely, more evidence is required to better guide the care of elderly patients with hip fracture during the subacute recovery period and convalescence.

Cost-effectiveness of pressure-relieving devices for the prevention and treatment of pressure ulcers

The cost-effectiveness of alternating pressure-relieving devices, mattress replacements, and mattress overlays compared with a standard hospital (high-specification foam mattress) for the prevention and treatment of pressure ulcers in hospital patients in the United Kingdom was investigated. A decision-analytic model was constructed to evaluate different strategies to prevent or treat pressure ulcers. Three scenarios were evaluated: the prevention of pressure ulcers, the treatment of superficial ulcers, and the treatment of severe ulcers. Epidemiological and effectiveness data were obtained from the clinical literature. Expert opinion using a rating scale technique was used to obtain quality of life data. Costs of the devices were obtained from manufacturers, whereas costs of treatment were obtained from the literature. Uncertainty was explored through probabilistic sensitivity analysis. Using 30,000 pounds sterling/QALY (quality-adjusted life year) as the decision-maker's cut off point (the current UK standard), in scenario 1 (prevention), the cost-effective strategy was the mattress overlay at 1, 4, and 12 weeks. In scenarios 2 and 3, the cost-effective strategy was the mattress replacement at 1, 4, and 12 weeks. Standard care was a dominated intervention in all scenarios for values of the decision-maker's ceiling ratio ranging from 5,000 pounds sterling to 100,000 pounds sterling/QALY. However, the probabilistic sensitivity analysis results reflected the high uncertainty surrounding the choice of devices. Current information suggests that alternating pressure mattress overlays may be cost-effective for the prevention of pressure ulcers, whereas alternating pressure mattress replacements appears to be cost-effective for the treatment of superficial and severe pressure ulcers.

Support surfaces for pressure ulcer prevention.

Pressure ulcers (also known as bedsores, pressure sores, decubitus ulcers) are areas of localised damage to the skin and underlying tissue due to pressure, shear or friction. They are common in the elderly and immobile and costly in financial and human terms. Pressure-relieving beds, mattresses and seat cushions are widely used as aids to prevention in both institutional and non-institutional settings. This systematic review seeks to answer the following questions: to what extent do pressure-relieving cushions, beds, mattress overlays and mattress replacements reduce the incidence of pressure ulcers compared with standard support surfaces? how effective are different pressure-relieving surfaces in preventing pressure ulcers, compared to one another? The Specialised Trials Register of the Cochrane Wounds Group (compiled from regular searches of many electronic databases including MEDLINE, CINAHL and EMBASE plus handsearching of specialist journals and conference proceedings) was searched up to January 2004, Issue 3, 2004 of the Cochrane Central Register of Controlled Trials was also searched. The reference sections of included studies were searched for further trials. Randomised controlled trials (RCTs), published or unpublished, which assessed the effectiveness of beds, mattresses, mattress overlays, and seating cushions for the prevention of pressure ulcers, in any patient group, in any setting. RCTs were eligible for inclusion if they reported an objective, clinical outcome measure such as incidence and severity of new of pressure ulcers developed. Studies which only reported proxy outcome measures such as interface pressure were excluded. Trial data were extracted by one researcher and checked by a second. The results from each study are presented as relative risk for dichotomous variables. Where deemed appropriate, similar studies were pooled in a meta analysis. 41 RCTs were included in the review. Foam alternatives to the standard hospital foam mattress can reduce the incidence of pressure ulcers in people at risk. The relative merits of alternating and constant low pressure devices, and of the different alternating pressure devices for pressure ulcer prevention are unclear.Pressure-relieving overlays on the operating table have been shown to reduce postoperative pressure ulcer incidence, although one study indicated that an overlay resulted in adverse skin changes. One trial indicated that Australian standard medical sheepskins prevented pressure ulcers. There is insufficient evidence to draw conclusions on the value of seat cushions, limb protectors and various constant low pressure devices as pressure ulcer prevention strategies.A study of Accident & Emergency trolley overlays did not identify a reduction in pressure ulcer incidence. There are tentative indications that foot waffle heel elevators, a particular low air loss hydrotherapy mattress and an operating theatre overlay are harmful. In people at high risk of pressure ulcer development, consideration should be given to the use of higher specification foam mattresses rather than standard hospital foam mattresses. The relative merits of higher-tech constant low pressure and alternating pressure for prevention are unclear. Organisations might consider the use of pressure relief for high risk patients in the operating theatre, as this is associated with a reduction in post-operative incidence of pressure ulcers. Seat cushions and overlays designed for use in Accident & Emergency settings have not been adequately evaluated.