Last reviewed: September 24, 2026
In this article
Support-surface assessment is part of both pressure-injury prevention and treatment. Changes in mobility, skin condition or care needs provide an opportunity to review whether the current surface remains appropriate. This article outlines the clinical considerations that may prompt assessment for a powered support surface. [1][2]
A 30-second read
Clinical takeaways
SS4 / SS12: Good practice statements
Whose surface needs reassessment?
Residents who cannot reposition independently, whose skin or clinical condition is deteriorating, or who have an immobility-related injury (SS12). [1] Risk scores and stage inform, but do not decide, surface selection (SS4). [1][2]
SS11 / SS15: Conditional recommendations · Very-low-certainty evidence
Match functions to assessed needs.
Alternating pressure provides active pressure redistribution. [1][5] Low air loss may assist in managing skin heat and moisture. [7] The guideline suggests it for at-risk residents, especially when heat and moisture contribute (SS11), and for existing Stage 2–4 or unstageable pressure injuries (SS15). [1]
For Directors of Care and purchasers: ask the manufacturer for standardized performance-test data, not the “low air loss” label alone. [7]
Section 1 · When to reassess
Recognizing when to reassess the support surface.
- SS4 · Individualized selection · good practice
- “Usually reserved” for higher risk · Surfaces ch., p. 9
The 2026 International Guideline treats surface selection as good practice matched to the person: overall risk, the response of the skin and tissues, independence, mobility and activity, posture and sleeping position, the need for microclimate management and shear reduction, and preferences and care goals (SS4). [1] It also describes when an air surface usually enters the plan:
“Alternating pressure (active) air or air (reactive) full body support surfaces are usually reserved for individuals at higher risk or deteriorating skin condition or clinical condition.”
International Guideline, 4th ed. · Full Body Support Surfaces · 2026 [1]
Ontario’s quality standard states the same expectation: people who have developed, or are at risk of, a pressure injury are provided with appropriate support surfaces based on their assessment. [2]
The largest pragmatic trial of alternating pressure versus high-specification foam, in acutely ill, high-risk adults in UK secondary and community inpatient facilities, asked who gained the most. Its exploratory analysis suggested potential benefit in people who were completely immobile, had altered skin or a Stage 1 (Category 1) injury at baseline, had a nutritional problem, or lacked the capacity to consent and took part through consultee agreement. [3] Canada’s health-technology agency concluded that reactive air and alternating-pressure air surfaces may be more effective than foam at preventing pressure injuries, with effectiveness influenced by setting and follow-up time. [4]
Alternating pressure may reduce new pressure injuries
Estimated people developing a new pressure injury per 1,000
- Alternating pressure: 67 per 1,000
- Foam reference: 106 per 1,000
An estimated
39 fewer
per 1,000 people in the network estimate
Cochrane network meta-analysis, alternating pressure versus foam
At a baseline risk of 106 people per 1,000 on foam, about 67 per 1,000 on alternating-pressure air surfaces. 95% confidence interval: 8 to 62 fewer. Low-certainty evidence, reported as “may reduce.” Reference follow-up about 14 days.
40 studies and 12,517 participants describe the whole prevention network. The estimate concerns people developing a pressure injury, not the number of individual wounds.
Shi et al., Cochrane Database Syst Rev 2021 [5]
These findings support assessment-based selection rather than product-first decisions. In practice, six bedside observations should prompt a surface assessment:
Observation 01
Cannot reposition independently
The resident depends on staff for every position change. Sustained load between scheduled repositioning is what active pressure redistribution is designed to address. [1][3][5]
Observation 02
Limited positioning options
Redness or injury on more than one turning surface can limit positioning options. The guideline treats this as a reason to re-evaluate the surface (SS12). [1]
Observation 03
Long hours in one lying position
People who cannot organize themselves into a stable midline posture may spend up to 12 hours a day in the same position when lying unsupported. [6] Posture and sleeping position are selection factors (SS4). [1]
Observation 04
Heat and moisture at the skin–surface interface
Sweating, incontinence or wound drainage beyond what dressings and absorptive products manage. Heat and moisture at the skin–surface interface are reasons to assess microclimate-management needs. [1][7][8]
Observation 05
Changes in skin integrity
Altered skin or a Stage 1 (Category 1) injury at baseline was associated with potential benefit from alternating pressure versus high-specification foam in PRESSURE 2’s exploratory analysis of acutely ill, high-risk UK inpatients. [3]
Observation 06
Deterioration despite the current prevention plan
Skin or wound decline despite an individualized plan means the current surface and care plan need reassessment. The guideline notes that the surface on which a pressure injury developed usually does not provide an appropriate environment for healing. [1]
A risk score informs assessment but does not determine the appropriate support surface on its own. [1][2]
Section 2 · Clinical presentations
Clinical presentations that warrant assessment.
- RESNA 2025 · populations
- NPIAP · tissue-tolerance factors
The following presentations may involve changes in mobility, posture, skin integrity or moisture management. Assessment should identify the resident’s needs rather than rely on diagnosis alone.
Presentation 01
Advanced age with comorbidity
Age-related skin change, reduced independent movement, and the tissue-tolerance factors in the NPIAP definition — microclimate, nutrition, perfusion, comorbidities and the condition of the soft tissue — commonly occur together. [3][9]
Presentation 02
Neurological and neuromuscular conditions
RESNA’s 2025 position names people with multiple sclerosis, ALS, muscular dystrophy, spinal cord injury, acquired brain injury, stroke, intellectual disability and advanced dementia among those who cannot easily move in and out of a stable midline position. Limited independent movement is the trigger for assessment — not the diagnosis itself. [1][3][6]
Presentation 03
Postural changes and contractures
Fixed postures, including those associated with cerebral palsy and arthritis, concentrate load on a small number of sites and make offloading harder (SS4, SS12). [1][6][10]
Presentation 04
Cardiopulmonary limitation
When clinical condition — for example COPD or heart failure — limits activity, mobility, or how often a person can be repositioned, both surface selection (SS4) and the repositioning interval (R5) are individualized to that condition. If the same person is diaphoretic, moisture management becomes a second, separate consideration (SS11). [1][8][11]
Presentation 05
Advanced illness and palliative care
In palliative and end-of-life care, comfort and the resident’s preferences are important considerations in surface selection. The International Guideline identifies alternating-pressure surfaces as an option when a different surface is sought for comfort or less frequent repositioning is preferred. Repositioning remains individualized to the resident’s condition, comfort and goals of care. [1][11]
Presentation 06
Heat and moisture at the skin–surface interface
Uncontained incontinence, diaphoresis or heavy exudate. The guideline suggests low air loss “especially when moisture and heat at the skin-surface interface are contributing factors” (SS11), and separately for existing Stage 2–4 or unstageable pressure injuries (SS15). McNichol and colleagues (Nursing, 2020) note that a moisture-dissipating surface may be indicated for the diaphoretic resident, or for copious wound drainage or incontinence not contained by dressings or absorptive products. [1][8]
These presentations prompt an assessment; they do not, on their own, indicate a powered surface.
Section 3 · Surface functions
Alternating pressure and low air loss: complementary functions.
- SS11 / SS15: Conditional recommendations · Very-low-certainty evidence
- NPIAP S3I 2024 · definition
A “powered surface” is not one therapy. Two important functions are in play, and many systems provide one or both. Understanding each function helps match the system to the resident’s assessed needs.
Alternating pressure — active pressure redistribution. Air cells cyclically change which areas of the body carry load, rather than relying only on the person changing position. Consider this function when a resident cannot reposition, cannot be positioned off an at-risk area, or is deteriorating on a reactive surface. [1][3][5] This is the function behind the prevention evidence compared with foam.
Low air loss — heat and moisture management. The Support Surface Standards Initiative defines low air loss as a construction that:
“uses a flow of air to assist in pressure redistribution and may assist in managing the heat and humidity (microclimate) of the skin.”
NPIAP S3I · Low Air Loss Terminology Position Statement · 2024 [7]
The Cochrane overview notes that low-air-loss features are designed to improve the skin microclimate, particularly for people with incontinence. [5] The 2026 guideline suggests low air loss for people at risk, especially when moisture and heat contribute (SS11), and for existing Stage 2–4 or unstageable pressure injuries (SS15). [1]
Low air loss in a nursing-home trial — Ferrell 1993
9.0 vs 2.5
Median wound-area healing rate (mm²/day), low-air-loss bed vs 10-cm foam
- Population
- 84 US nursing-home residents with existing trunk or trochanter (hip) pressure injuries
- Design
- Randomized trial — low-air-loss bed vs 10-cm foam mattress
- Measure
- This figure measures the rate of reduction in wound area — not the proportion of injuries that healed completely.
- Context
- A 1993 bed system. The trial speaks to existing injuries (SS15), not the moisture picture, and does not rank current mattresses.
Ferrell et al., JAMA 1993; figures as reproduced in Cochrane CD013624 [12][13]
When both needs are present. For a resident who cannot reposition independently and also has heat and moisture concerns, assessment should consider both pressure redistribution and microclimate management. A system combining alternating pressure and low air loss may help address these needs. Selection and reassessment remain individualized. [1][7]
No support surface replaces repositioning. The interval may be adjusted to the surface and the person’s response; the surface supports the plan between position changes. [11]
Section 4 · Purchasing considerations
Cost-effectiveness and purchasing considerations.
- Cochrane 2021 · “probably more cost-effective” · moderate certainty
- PRESSURE 2 · economic analysis
Cost-effectiveness evidence
A 2021 Cochrane review concluded that alternating-pressure air surfaces are probably more cost-effective than foam for pressure injury prevention.
Moderate-certainty evidence · One UK trial’s economic analysis
Cost-effectiveness considers both costs and health outcomes — not purchase price alone. These findings do not establish savings for an individual Canadian facility.
In the largest trial’s economic analysis — a UK study — the alternating-pressure arm had slightly lower total costs and marginally more quality-adjusted life-years than foam, though the trial authors judged the result not robust. [3]
A resident-specific clinical rationale can support equipment approval or a funding request. Record the assessed needs, required surface functions and reasons for the proposed change. Documentation requirements vary by facility and payer. The NPIAP’s selection guidance recommends choosing on manufacturer performance data and evaluating equipment with feedback from bedside clinicians and the people using it. [7]
Section 5 · Practical next steps
From assessment to surface selection.
- SS12 · Re-evaluate the surface · good practice
- S3I · Ask for performance data
- 01Assess the person — mobility, skin and tissue response, moisture, pain, size and weight, posture and sleeping position, goals of care (SS4). [1]
- 02Identify the functions required — active pressure redistribution (alternating pressure), heat-and-moisture management (low air loss), or both.
- 03Ask for performance evidence, not labels — the NPIAP S3I recommends selecting on standardized performance-characteristic test data from the manufacturer rather than on the phrase “low air loss” alone. [7]
- 04Set up properly and educate the team — correct configuration, fit to the bed frame, side rails and the resident’s size and weight, bedding per the manufacturer’s instructions, and clear staff responsibility for daily checks.
- 05Monitor and reassess — regular skin checks, checks for bottoming out performed to the manufacturer’s instructions, equipment inspected at least daily while in use (SS1), and re-evaluation of the surface after any change in condition or any new immobility-related injury (SS12). [1]
- 06Continue repositioning — no support surface replaces repositioning and skin assessment; repositioning intervals remain individualized alongside the surface. [11]
Before a purchase, a demonstration answers the practical questions:
Ask 01
Setup and training
Who configures the surface for this resident, how is setup verified after the first transfer, and what training does the team need?
Ask 02
Automatic settings and team checks
Which settings adjust automatically, and which checks remain the care team’s responsibility?
Ask 03
Noise and comfort
How does the pump sound at the bedside, and how comfortable is the surface for this resident?
Ask 04
Bedding
Which sheets and pads preserve the airflow and immersion the surface is meant to deliver?
Ask 05
Care and transfers
How does the surface firm for staff-assisted repositioning, personal care, sling application and transfers?
Ask 06
Cleaning and infection prevention
Are the manufacturer’s cleaning instructions compatible with the facility’s infection-prevention protocols?
A demonstration allows the team to assess these practical requirements in the intended care environment.
For community settings, the assessment extends to the environment: available space and access, reliable electricity and pump placement, bed and surface fit for the person’s size and weight, and clear information for carers on cleaning, inspection and maintenance. [1]
Hypothetical teaching scenario · for discussion
Example: reassessing a resident’s support surface
A long-term-care resident in her late eighties with advanced Parkinson disease no longer repositions herself. She spends most of the day in bed, perspires heavily, and briefs and dressings are not keeping her skin dry. This week the evening nurse documents a persistent, non-blanching red area over the sacrum — on a foam mattress with no faults found on the checks set out in the manufacturer’s instructions.
Reviewed against the considerations above: she cannot reposition independently, her moisture is not contained, and her skin is changing on a reactive surface that shows no faults (SS12). These findings warrant a prompt review of the support surface and care plan — including whether a system combining alternating pressure and low air loss would meet her assessed needs, alongside her individualized repositioning plan.
Takeaway Review the resident’s skin findings, positioning options, moisture management and current surface together, then document the rationale for any change.
Questions teams ask
Education for your team
Powered-surface education for your long-term-care team.
Request an in-service on recognizing residents who may benefit from a powered-surface assessment, understanding alternating pressure and low air loss, and practical setup and use. Bring your team’s questions and anonymized resident examples.
Or ask about a dealer-coordinated demonstration.
About Evergreen. An Evergreen educational summary of published studies and guidelines. Practical examples illustrate application. The sources do not endorse Evergreen or its products. Support surfaces do not replace repositioning. Selection and use should be based on individual clinical assessment and the product instructions for use.
Explore Evergreen’s powered surfaces.
These links describe Evergreen’s range. They are not study endorsements or product-specific evidence.
References
- European Pressure Ulcer Advisory Panel, National Pressure Injury Advisory Panel, Pan Pacific Pressure Injury Alliance. Full Body Support Surfaces. In: Prevention and Treatment of Pressure Ulcers/Injuries: International Clinical Practice Guideline. 4th ed.; chapter dated 20 May 2026. (SS1, SS4, SS11, SS12, SS15; “usually reserved,” printed p. 9.) internationalguideline.com/surfaces
- Ontario Health (Health Quality Ontario). Pressure Injuries: Care for Patients in All Settings. Quality Standard; 2017. Quality Statement 5. hqontario.ca/Evidence-to-Improve-Care/Quality-Standards/View-all-Quality-Standards/Pressure-Injuries
- Nixon J, Brown S, Smith IL, et al. Comparing alternating pressure mattresses and high-specification foam mattresses to prevent pressure ulcers in high-risk patients: the PRESSURE 2 RCT. Health Technol Assess. 2019;23(52). doi:10.3310/hta23520
- Vu T, Askin N. Therapeutic Support for Pressure Injuries. CADTH Health Technology Review RC1450. Can J Health Technol. 2022;2(9). canjhealthtechnol.ca/index.php/cjht/article/view/RC1450
- Shi C, Dumville JC, Cullum N, et al. Alternating pressure (active) air surfaces for preventing pressure ulcers. Cochrane Database Syst Rev. 2021;(5):CD013620. doi:10.1002/14651858.CD013620.pub2. And: Beds, overlays and mattresses for preventing and treating pressure ulcers — overview and network meta-analysis. 2021;(8):CD013761. pmc.ncbi.nlm.nih.gov/articles/PMC8407250
- RESNA. RESNA Position on Assistive Technology for Lying Posture Care Management. Approved 26 February 2025. Assistive Technology. 38(1):51–60. doi:10.1080/10400435.2025.2543691
- National Pressure Injury Advisory Panel, Support Surface Standards Initiative. Low Air Loss Terminology Position Statement (2024); Support Surface Selection Steps. npiap.com/page/S3I
- McNichol L, Mackey D, Watts C, Zuecca N. Choosing a support surface for pressure injury prevention and treatment. Nursing. 2020;50(2):41–44. (Printed pp. 43–44.) doi:10.1097/01.NURSE.0000651620.87023.d5. pmc.ncbi.nlm.nih.gov/articles/PMC7329246
- National Pressure Injury Advisory Panel. Pressure injury stages — definition and tissue-tolerance factors. cdn.ymaws.com/npiap.com/resource/resmgr/online_store/npiap_pressure_injury_stages.pdf
- Hill S, Goldsmith J. Biomechanics and prevention of body shape distortion. Tizard Learning Disability Review. 2010;15(2):15–29. doi:10.5042/tldr.2010.0166
- European Pressure Ulcer Advisory Panel, National Pressure Injury Advisory Panel, Pan Pacific Pressure Injury Alliance. Repositioning and Mobilization. In: International Clinical Practice Guideline. 4th ed.; chapter dated 14 May 2026. (R1, R5.) internationalguideline.com/repositioning
- Ferrell BA, Osterweil D, Christenson P. A randomized trial of low-air-loss beds for treatment of pressure ulcers. JAMA. 1993;269(4):494–497. doi:10.1001/jama.1993.03500040060037. Abstract: https://jamanetwork.com/journals/jama/article-abstract/403027 — study characteristics and results are also reported in Cochrane CD013624 (reference 13).
- Shi C, Dumville JC, Cullum N, Rhodes S, Jammali-Blasi A, Ramsden V, McInnes E. Beds, overlays and mattresses for treating pressure ulcers. Cochrane Database Syst Rev. 2021;(5):CD013624. doi:10.1002/14651858.CD013624.pub2. https://doi.org/10.1002/14651858.CD013624.pub2 — “Characteristics of included studies: Ferrell 1993” (in the full Cochrane record). Narrative also at https://pmc.ncbi.nlm.nih.gov/articles/PMC8108042/
Continue the clinical pathway
This article is an educational resource for healthcare professionals. It is not intended to replace clinical judgment, individualized resident assessment, facility policy, or product instructions for use.