Why Viscoelastic Memory Foam may not be ideal for pressure-relieving mattresses
1. Temperature dependent behaviour
Viscoelastic Memory Foam mattresses are highly temperature sensitive, becoming softer with warmth and firmer when cool. This can lead to an inconsistent or delay in effective pressure redistribution and potentially an increase in shear forces, due to the temperature of the foam during repositioning (NPIAP et al., 2025).
2. Excessive immersion and envelopment
Memory foam allows deep body immersion, which can lead to restricted spontaneous movement and increased shear forces during repositioning. Excessive envelopment may also increase the risk of bottoming out in heavier patients (Wounds International, 2010; NPIAP et al., 2025). This can lead to some patients experiencing a sense of being ‘stuck’ when shifting position on memory foam mattresses, and lead to a reduction in a patient’s independent mobility.
3. Microclimate management
Viscoelastic foam retains heat and moisture due to low airflow and deep envelopment. Poor microclimate control increases the risk of skin maceration and pressure ulcers. Pressure relieving surfaces should prioritise breathability, moisture dissipation, and temperature regulation. Therefore, the newer microclimate-regulating multi-layer surfaces have been shown to reduce pressure ulcer incidence compared with Viscoelastic foam (van Leen et al., 2018.).
4. Long-term performance
Visco foam is prone to material fatigue, permanent indentations, and inconsistent long-term performance. Clinically engineered foams provide more predictable pressure redistribution (Blackburn, 2024; CADTH, 2009).
5. Nursing workload and handling safety
Deep contouring increases the effort required for repositioning and may interfere with profiling on adjustable beds, increasing shear and nursing workload (Wounds International, 2010; NPIAP et al., 2025).
Conclusion
Across the last 15 years of evidence, Viscoelastic memory foam underperforms compared with other combinations of foam support surfaces in pressure redistribution, microclimate control, shear reduction. Ensuring excellent microclimate control while promoting a patient’s independent mobility are aspects of pressure relief that need to be considered when choosing the right foam mattress.
References
Blackburn, J., (2024). Effectiveness of pressure-relieving mattresses on pressure ulcers. Wounds UK, 20(4), pp.12–18. Available at chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://wounds-uk.com/wp-content/uploads/2024/11/WUK20_4_12-18-Blackburn-v4.pdf
Canadian Agency for Drugs and Technologies in Health (CADTH), (2009). Specialty mattresses for the prevention and management of pressure ulcers: A review of the clinical effectiveness, cost-effectiveness, and guidelines. CADTH, Ottawa. Available at https://www.cda-amc.ca/sites/default/files/pdf/L0150_Mattresses_Pressure_Ulcers.pdf
National Pressure Injury Advisory Panel, European Pressure Ulcer Advisory Panel and Pan Pacific Pressure Injury Alliance, 2025. Full body support surfaces for prevention of pressure injuries (Part 1). In: E. Haesler (ed.) Prevention and treatment of pressure ulcers/injuries: Clinical practice guideline. The International Guideline. Fourth edition. Available at chrome-extension://efaidnbmnnnibpcajpcglclefindmkaj/https://static1.squarespace.com/static/6479484083027f25a6246fcb/t/67beef3646e2427a2d0cdfa8/1740566329428/2025-Guideline-Supports-25Feb25.pdf
van Leen, M., Halfens, R. and Schols, J. (208). Preventive effect of a microclimate-regulating system on pressure ulcer development: A prospective, randomized controlled trial in Dutch nursing homes.
Adv Skin Wound Care, 31(1):1-5.doi:10.1097/01.ASW.0000527288.35840.0a.. Available at https://pubmed.ncbi.nlm.nih.gov/29240594/
Wounds International, (2010). Pressure ulcer prevention: Pressure, shear, friction and microclimate in context. An international review. Wounds International, London. Available at https://woundsinternational.com/consensus-documents/international-review-pressure-ulcer-prevention-pressure-shear-friction-and-microclimate-context/
