Standard Mattress Research Articles

Prevention of pressure ulcer: interaction of body characteristics and different mattresses

We analysed the effect of different body features on contact area, interface pressure and pressure distribution of three different mattresses. Thirty-eight volunteers (age ranged from 17 to 73 years, 23 females) were asked to lie on three different mattresses in a random order: I, standard hospital foam mattresses; II, higher specification foam mattresses (Viscorelax Sure® ); III, constant low pressure devices (CareMedx® , AirSystems). Measurements were performed in supine position and in a 90° left- and right-sided position, respectively, using a full-body mat (pressure mapping device Xsensor X2-Modell). Outcome variables were contact area (CA) in cm(2) , mean interface pressure (IP) in mmHg and pressure distribution (PD) estimated as rate of low pressures between 5 and 33 mmHg on each mattress in percent. Mean CA was lowest in the standard hospital foam mattresses and increased in the higher specification foam mattresses and was highest in the constant low pressure device (supine position: 491 ± 86 cm(2) , 615 ± 95 cm(2) , 685 ± 116 cm(2) ). Mean IP was highest in the standard hospital foam mattresses and lower but similar in the higher specification foam mattresses and the constant low pressure devices (supine position: 22·3 ± 1·5 mmHg, 17·6 ± 1·7 mmHg, 17·6 ± 2·2 mmHg). Models were estimated for CA, IP and PD including the independent variables height, weight and waist-to-hip-ratio (WHR). They show that body morphology seems to play a minor role for CA, IP and PD, but very thin and tall patients and very small and obese people might benefit from different mattresses. Our data show that CA increases with increasing specification of mattresses. Higher specification foam mattresses and constant low pressure devices show similar IP, but constant low pressure devices show a wider pressure distribution. Body morphology should be considered to optimise prevention for single patients.

Support surfaces for intraoperative prevention of pressure ulcers in patients undergoing surgery: A cost-effectiveness analysis

Patients who undergo prolonged surgical procedures are at risk of developing pressure ulcers. Recent systematic reviews suggest that pressure redistribution overlays on operating tables significantly decrease the associated risk. Little is known about the cost effectiveness of using these overlays in a prevention program for surgical patients. Using a Markov cohort model, we evaluated the cost effectiveness of an intraoperative prevention strategy with operating table overlays made of dry, viscoelastic polymer from the perspective of a health care payer over a 1-year period. We simulated patients undergoing scheduled surgical procedures lasting ≥90 min in the supine or lithotomy position. Compared with the current practice of using standard mattresses on operating tables, the intraoperative prevention strategy decreased the estimated intraoperative incidence of pressure ulcers by 0.51%, corresponding to a number-needed-to-treat of 196 patients. The average cost of using the operating table overlay was $1.66 per patient. Compared with current practice, this intraoperative prevention strategy would increase slightly the quality-adjusted life days of patients and by decreasing the incidence of pressure ulcers, this strategy would decrease both hospital and home care costs for treating fewer pressure ulcers originated intraoperatively. The cost savings was $46 per patient, which ranged from $13 to $116 by different surgical populations. Intraoperative prevention was 99% likely to be more cost effective than the current practice. In patients who undergo scheduled surgical procedures lasting ≥90 min, this intraoperative prevention strategy could improve patients' health and save hospital costs. The clinical and economic evidence support the implementation of this prevention strategy in settings where it has yet to become current practice.

Relationship between mattress technological features and sleep quality: an actigraphic study of healthy participants

The introduction of new mattresses with innovative technology has led to a significant improvement in objective sleep quality. We aimed to explore whether this improvement in sleep quality was merely due to the introduction of a new mattress regardless of the innovative level of its technological features. Twenty-eight healthy volunteers tested a standard technology mattress (traditional spring mattress) and a new technology mattress in expanded polyurethane and visco-elastic (Myform®). Sleep quality was assessed before and after introducing the new mattresses, objectively (through actigraphy) and subjectively (through the Mini Sleep Questionnaire). Myform® led to a significant improvement in actigraphic sleep parameters of sleep onset latency and sleep efficiency. Therefore it is not enough to introduce a new mattress with any technology in order to determine a significant objective sleep quality improvement; the innovative technological features of the mattress seem to be fundamental.

Optimal configuration of the spiral linking technique for tendon repair. Biomechanical evaluation

A previous study described a new spiral linking technique for tendon repairs and demonstrated that it was strong enough to be used in clinical practice as an alternative to the Pulvertaft tendon weave repair. However the repairs were less stiff, needed slightly more tendon length for the same repair and were a little bulkier. In this study two variables have been changed with a view to improving the spiral technique. At first the number of spirals was reduced consecutively, keeping the same number of standard mattress sutures. Once the optimal number of spirals had been identified, repairs with different numbers of sutures were tested using an alternative cross-stitch technique. The spiral repair technique using two spirals linked with six sutures was at least as strong and stiff as a four-weave Pulvertaft technique and was also easier to do.

Aeration properties of a new sleeping surface for infants

Prone sleeping position, use of soft mattresses and head covering by bedclothes are known risk factors for sudden infant death syndrome (SIDS). Rebreathing carbon dioxide (CO(2) ) may be a possible mechanism or a confounding factor of SIDS. To compare the aeration properties of a new concept of infant sleeping surface (Net) to three commercial mattresses advertised to improve aeration and to two standard infant mattresses. Two experiments were performed: (I) A container (head box), filled with 7% CO(2) mixture, was opened to the mattress to allow gas mixture to passively diffuse outside and equilibrate with the surrounding room air. (II) Simulation of normal breathing of an infant, using a unidirectional reciprocal syringe, to determine CO(2) accumulation within the head box. CO(2) concentrations in the head box were continuously measured until CO(2) levels fell below 1% or for 5 min (experiment I), or until CO(2) accumulation levels plateaued or for 6 min (experiment II). The Net had a significantly faster rate of CO(2) elimination (88.5 ± 4.6 and 91.9 ± 0.9 sec, Net alone and when covered with a sheet, respectively) compared to 238.3 ± 14.2 sec to 387.8 ± 7.9 sec for the other mattresses (P < 0.001). Only the Net was able to prevent CO(2) accumulation with maximal CO(2) levels (0.56 ± 0.03% and 1.16 ± 0.05%; Net alone and when covered with a sheet, respectively) significantly lower than the range of 4.6-6.3% for the other mattresses (P < 0.001). The new sleeping surface exhibited significantly better aeration properties in dispersing CO(2) and in preventing its accumulation.

Should care homes adopt a static-led approach to pressure ulcer prevention?

A static-led approach refers to the provision of high-specification foam mattresses for the whole of a population at risk of pressure damage. Such mattresses have been found to reduce the risk of pressure ulceration and cost less overall than standard mattresses, even in populations where only 1 in 100 patients develops a pressure ulcer. Reduced pressure ulcer prevalence and reduced costs resulting from decreased expenditure on dynamic mattresses following the implementation of a static-led approach have been reported. Pressure ulcers cause pain, a reduced quality of life, loss of independence, depression and social isolation for those in whom they develop. Organizations are increasingly having to pay out large sums of money following litigation surrounding pressure ulcers. This article explains why NHS healthcare providers and private care organizations need to work together to consider implementing a static-led approach to pressure ulcer prevention within care homes in order to reduce pressure ulcer incidence cost-effectively within their local populations.

A Simulation Study of Gel Pillow Heat Conductance

The gel-filled pillow is a device used to provide a soft surface to support and cradle an infant's head. Little is known about the thermal conductive properties of this device when used in an open crib. This simulation study evaluated the use of the Squishon 2 gel pillow in an open crib to determine the potential cooling effects on a mannequin infant. This simulation study was conducted on a thermal mannequin. A descriptive comparative repeated-measures design was employed. A thermal mannequin with the head placed on the gel pillow was used. The energy required to keep the mannequin head at 37 degrees C in 4 conditions was measured. The 4 conditions were as follows: (1) lying in an open crib on a standard mattress (baseline), (2) lying on the gel pillow with the disposable cover from the manufacturer, (3) the head wearing a cap and lying on the gel pillow, and (4) the head without the hat lying on the gel pillow with an insulated cover over the pillow. Univariate analysis of variance (ANOVA) revealed significant differences in energy required to maintain the mannequin head at 37 degrees C among the 4 conditions (F3 = 283.23, P = .0001). The hat on head condition was found to decrease energy utilization by an average of 6.36 kcal/d when compared with the head on mattress condition (P = .0001). Extrapolation of energy to maintain mannequin head warmth into potential kilocalories utilized revealed that a potential increase in kilocalories needed to maintain thermoneutrality would be needed. The most effective way of conserving heat was in the hat on the mannequin head while lying on a gel pillow condition. The use of a gel pillow without a hat or an insulated barrier caused an increase in energy requirements and kilocalorie usage in this mannequin model. The results of this simulation study suggest that use of the gel pillow outside of a thermally controlled environment and in an open crib environment may increase energy use to maintain thermoneutrality. The Squishon 2 gel pillow conducts heat from the mannequin head and may increase kilocalories per day consumption in the preterm infant. Furthermore, the results of the study support previous findings that a hat helps conserve energy.

Review: alternative-foam mattresses and some operating-table overlays reduce pressure ulcers more than standard surfaces

Do pressure-relieving surfaces reduce pressure ulcers more than standard support surfaces? Are some types of pressure-relieving surfaces more effective than others? Included studies were randomised controlled trials (RCTs) that compared...

Treatment of Pressure Ulcers

Many treatments for pressure ulcers are promoted, but their relative efficacy is unclear. To systematically review published randomized controlled trials (RCTs) evaluating therapies for pressure ulcers. The databases of MEDLINE, EMBASE, and CINAHL were searched (from inception through August 23, 2008) to identify relevant RCTs published in the English language. Methodological characteristics and outcomes were extracted by 3 investigators. A total of 103 RCTs met inclusion criteria. Of these, 83 did not provide sufficient information about authors' potential financial conflicts of interest. Methodological quality was variable. Most trials were conducted in acute care (38 [37%]), mixed care (25 [24%]), or long-term care (22 [21%]) settings. Among 12 RCTs evaluating support surfaces, no clear evidence favored one support surface over another. No trials compared a specialized support surface with a standard mattress and repositioning. Among 7 RCTs evaluating nutritional supplements, 1 higher-quality trial found that protein supplementation of long-term care residents improved wound healing compared with placebo (improvement in Pressure Ulcer Scale for Healing mean [SD] score of 3.55 [4.66] vs 3.22 [4.11], respectively; P < .05). Other nutritional supplement RCTs showed mixed results. Among 54 RCTs evaluating absorbent wound dressings, 1 found calcium alginate dressings improved healing compared with dextranomer paste (mean wound surface area reduction per week, 2.39 cm(2) vs 0.27 cm(2), respectively; P<.001). No other dressing was superior to alternatives. Among 9 RCTs evaluating biological agents, several trials reported benefits with different topical growth factors. However, the incremental benefit of these biological agents over less expensive standard wound care remains uncertain. No clear benefit was identified in 21 RCTs evaluating adjunctive therapies including electric current, ultrasound, light therapy, and vacuum therapy. Little evidence supports the use of a specific support surface or dressing over other alternatives. Similarly, there is little evidence to support routine nutritional supplementation or adjunctive therapies compared with standard care.

Evaluating the effectiveness of gel pillows for reducing bilateral head flattening in preterm infants: a randomized controlled pilot study

This study evaluated the effectiveness of gel pillows for reducing bilateral head molding (plagiocephaly) in preterm infants, as determined by the cephalic index (CI). Eighty-one infants weighing <1,500 g were randomly assigned at birth to usual care on a standard mattress ( n = 40) or to placement on a gel pillow ( n = 41). The CI was measured with a digimatic caliper upon entry and weekly thereafter, until infants had been transferred or discharged. Repeated measures analysis of variance revealed no statistically significant differences in the CI between subjects upon entry, at 5 weeks postintervention, or at 10 weeks postintervention. The trend was toward less molding over time for smaller infants on gel pillows who were hospitalized longer; however, the sample size was too small to detect statistical significance.

Usage of high‐performance mattresses for transport of Indo‐Pacific bottlenose dolphin

Ground transport can be a stressful operation for dolphins if the long period of restraint causes damage to internal organs, especially to the lung, generated by their own weight. Buoyancy is deprived from dolphins under moist transport, in which dolphins are transported on mattresses. Upgrading mattresses is an effective way to modify the transportation method so as to compensate for the loss of buoyancy. In Indo-Pacific bottlenose dolphins (Tursiops aduncus), we tried to find mattresses that performed well at distributing the dolphins' weight and preserved their pulmonary function. When using EV-17 (thickness, 50 mm) put on EE-20 (thickness, 50 mm), a wider support area, less extreme changes in pressure, and lower maximum pressures were observed compared with other mattress systems tested. On this mattress system, lower breathing rates, lower heart rates, and higher exhaled CO(2) concentrations were shown compared with using standard mattresses. These results suggest that the performance of the combination of EV-17 and EE-20 is better than that of the standard mattress in terms of the cardiopulmonary function of dolphins. Zoo Biol 27:331-340, 2008. (c) 2008 Wiley-Liss, Inc.

Interface Pressure Comparison of Healthy Premature Infants With Various Neonatal Bed Surfaces

The aim of this study was to determine interface pressure between the occiput of healthy premature infants and 5 different bed surfaces used in special care nurseries. Thirteen healthy premature infants comprised the convenience sample enrolled 1 to 3 weeks prior to discharge. A quasi-experimental design was used with the dependent variable being the interface pressures obtained under the occiput and the independent variables as the bed surfaces. Order of bed surfaces was randomized and standardization of the infant positioning and measuring procedure maintained. Measurements were made between the infant's occiput and the bed surface and interface pressures recorded in millimeters of mercury. The 5 bed surfaces were standard crib mattress with or without foam, gel donut, gel mattress, and water pillow. Interface pressure measurements were obtained using the Mini-Texas Interface Pressure Evaluator (Mini-TIPE, Tee-Kay Applied Technology, Inc, Stafford, Texas). A 1-way blocked analysis of variance was conducted to evaluate the relationship between the mattress surfaces and the interface pressure measurements. A significant difference in the mean of the interface pressures among the 5 mattress bed surfaces was determined, F(4,46) = 33.267, P < .001, with the lowest being the foam overlay. The standard crib mattress had the highest interface pressure that exceeded 100 mm Hg. Post hoc comparisons showed a significant difference between the standard crib mattress with and without foam and the other surfaces. Interface pressure is an important consideration when choosing a support surface for premature infants susceptible to tissue compromise and head molding. Variations in interface pressures between neonatal bed surfaces are apparent. Comparison studies of interface pressures using these and other neonatal bed surfaces will be valuable in determining appropriate products for both premature and neonatal populations with lengthy intensive care stays.

Does a Foamy-Block Mattress System Prevent Pressure Sores ? A Prospective Randomised Clinical Trial in 1729 Patients

Background: Pressure ulcers are a frequent complication of bed rest. The development of an efficient and low cost pressure relieving system for the prevention of bed-sores would be of considerable hospital health and economic interest. Our study was designed to determine the effectiveness in pressure-sore prevention of an interface pressure-decreasing mattress, the Kliniplot® mattress, used in our institution since 1978.Methods: In a prospective randomised controlled 7-month clinical trial we compared the Kliniplot® mattress with our standard hospital mattress in 1729 patients admitted to medical and surgical departments (neurology, cardiology, oncology-haematology, neurosurgery, thoracic surgery and orthopaedic surgery). Two groups (Klinipot® mattress and standard hospital mattress) were monitored for the prevention of pressure sores. The patients were evaluated on a daily basis from their admission until the eventual occurrence of a bed-sore. Patients’ characteristics and pressure-sore risk factors were similar at the baseline in both groups. Patients presenting with a pressure sore at the time of admission were excluded.Results: Forty-two of the 1729 patients (2.4%) who entered the study developed at least one pressure sore. Twenty-one of the 657 patients (3.2%) nursed on the Kliniplot® mattress, and 21 of the 1072 patients (1.9%) on the standard mattress developed bed-sores (p = 0.154). The median time for the occurrence of pressure sores was 31 days (range 687) with the Kliniplot® mattress and 18 days (range 2 to 38) with the standard mattress (p < 0.001). The risk categories for developing bed-sores using the modified Ek’s scale were no different at the baseline between both groups (p = 0.764). The severity of the pressure sores was no different between both groups (p = 0.918).Conclusions: Our results show that the occurrence of pressure sores is not reduced but is delayed when patients are nursed on a Kliniplot® pressure-decreasing mattress.

L’escarre à l’hôpital en 2003 : enquête de prévalence un jour donné

To determine the prevalence of pressure sores in a university hospital and to assess the risk of developing a pressure sore. A one-day survey was performed in all hospitalized patients, day hospital excepted. The Garches scale was used to assess the severity of pressure sores and the Braden scale was used to measure the patient's risk for the development of pressure ulcers. One thousand six hundred and eleven patients were included, mean age was 62+/-23 years and 53.3% were over 65 years old. In hospitalized patients, 64% were in acute care, 29% in intermediate medicine and long-term care and 7% in intensive care units. We have found 675 pressure sores in 268 patients, mean age of 76 years; 263 decubitus ulcers were acquired during hospitalization. The most frequent sites were heels (46%) and sacrum (26%). Stage 1 pressure ulcers showed 33% of the total. The total prevalence was 16.6%, 95% CI (14.9-18.6), the hospital acquired pressure sores prevalence was 7.5%, all stages included. A Braden score less than or equal to 15 was found in 29.1% of hospitalized patients. Standard mattresses were used in 37% of patients with pressure sores. Multivariate analysis showed that age and a Braden score less than or equal to 15 were significantly associated with pressure sores. Pressure sores are still an important problem in hospital; occurrence must be considered as an iatrogenic event and management requires a multidisciplinary approach.

Softform Premier Active Mattress: a novel step-up/step-down approach

In the UK it is estimated that as many as 412,000 patients who are already ill will develop pressure ulcers (Bennett et al, 2004), which are an unnecessary and expensive complication to treat (Hitch, 1995). One way to try and reduce these risks is by investing in suitable mattresses. The author's investigations into existing mattress stock in the years 1996-97 illustrated the inadequacy of the NHS standard mattress (Santy, 1995; Fox, 1997). Investigators (e.g. Rithalia, 1996) were recognizing the inadequacy of the pink marbled standard NHS foam mattress for pressure reduction (Medical Device Directorate, 1993; Dunford, 1994) which included reports necessary to help develop guidelines in pressure ulcer prevention and management (Coull, 2004), as well as make value-for-money recommendations about product purchases (Fletcher et al, 1994; Value For Money Update, 1994; Cullum et al, 1995).

Comparison of Pressure Relief Properties of Operating Room Surfaces

There are many operating room (OR) mattresspads and overlay surfaces; however, little empir-ical evidence is available regarding the pressure-reducing characteristics of these various surfaces.Foam and gel mattresses, with and withoutviscoelastic overlays, have been reported to reducethe skin interface pressure more effectively thanthe standard OR mattress pad [1–4]. Defloor andDeSchuijmer [5] reported that although the foammattress and the gel mattress had little pressure-reducing properties, the polyurethane and thepolyethermattresssignificantly(P!.001)reducedinterface pressures. However, none of the OR sur-faces studied (eg, polyurethane, polyether, gelmattress, foam mattress, standard OR mattress)reduced the pressures to less than 32 mm Hg. Itis relatively routine to use foam padding and geloverlays with the impression that padding the pa-tientrelievespressureandpreventspressureulcers.Therefore, this performance improvement studywas undertaken to describe the peak skin interfacepressuresinthespineandlateralpositionsonthreecommonly used OR surfaces.A key issue when positioning surgical patientsis the prevention of skin injury. Ischemic injuryand the potential development of pressure ulcersis a concern for any patient who remains in oneposition for prolonged periods. Although theincidence of pressure ulcers in acute care popula-tions is between 3% and 29%, the incidence forsurgical patients is higher, between 12% and 35%[6–8].This increased incidence is due in part to thecombined extended period of uninterrupted pres-sure and the forced immobility during surgicalprocedures in conjunction with the effects of anes-thesia [9].Prolonged exposure of the skin and underlyingtissues to high interface pressure or exposure tolow pressure over extended periods may predis-pose the patient to ischemic injury. Ischemicinjury occurs with increased frequency overweight-bearing bony prominences covered byskin and a small amount of muscle and sub-cutaneous tissue. In the supine position, morevulnerable sites include the occiput, scapula,olecranon process, sacrum, ischial tuberosities,and the calcaneous. In the lateral position, theear, acromion process, iliac crest, greater trochan-ter, lateral knee, and malleolus are the bonyprominences of concern. For the purpose of thisproject, the peak interface pressures over thebony prominences (occiput, sacrum, greater tro-chanter, and heels) were of interest.External pressure on tissues at capillary in-terface pressures greater than 32 mm Hg mayocclude capillary blood flow causing diminishedtissue perfusion and an ischemic injury that maylater manifest as a pressure ulcer [10]. The dura-tion of pressure is thought to be more of a contrib-uting factor than the intensity of the pressure,with 2 hours or longer associated with the devel-opment of ischemic injury. Individuals who are

Prevention and Early Detection of Pressure Ulcers in Patients Undergoing Cardiac Surgery

Absence of pressure ulcers is increasingly being used as an indicator of quality nursing care, based on the premise that pressure ulcers are preventable. This retrospective study examined the occurrence, presentation, and timing of pressure ulcer development in 150 patients undergoing cardiac surgery. Pressure ulcer incidents were recorded in groups of patients who underwent surgery with use of a standard foam OR bed mattress; use of a fluid, pressure-reducing OR bed mattress; or use of a fluid, pressuring-reducing mattress after a comprehensive educational program on pressure ulcer prevention was presented to RNs. Tcers decreased when the fluid, pressure-reducing OR bed mattresses were used in conjunction with the comprehensive RN education program.

Interface pressure measurement during surgery: a comparison of four operating table surfaces.

To compare the pressure-reducing and pressure-redistributing characteristics of four operating room (OR) table mattresses using interface pressure measurements, in two positions adopted for surgical procedures. Support surfaces were randomly assigned to 80 patients. These were: an overlay pad filled with fibres (the standard OR mattress), a custom-made viscoelastic polyurethane foam mattress, an inflatable mattress with air-filled cells and a fluid mattress. An XSENSOR full-body pressure-mapping pad was used to record interface pressures of 40 patients in the supine position and 40 patients in the lithotomy position. Measurements were analysed for peak pressure, peak pressure index, total contact surface area and the occurrence of a significant increase in interface pressure during the surgical procedure. The highest interface pressures were measured on the standard mattress, in both the supine and lithotomy position. Overall, the fluid mattress showed the best pressure-reducing and pressure-redistributing capacities. As long as no reference values are available for interface pressures under which no pressure-related damage will occur, clinical testing of OR table surfaces is still necessary.

Biomechanical Evaluation of Meniscal Repair Systems

Background The biomechanical characteristics of the Meniscal Viper Repair System have not been previously studied. Hypothesis Comparable meniscal lesion fixation standards will exist among the Meniscal Viper Repair System, the vertical FasT-Fix device, and vertical mattress sutures. Study Design Controlled laboratory study. Methods Porcine menisci (3 groups of 7 menisci each) were repaired using different devices. A servohydraulic device cycled each construct between 5 N and 50 N for 500 cycles before load to failure (5 mm/min). Group differences were evaluated with 1-way analysis of variance and Tukey post hoc tests. Results During cyclic testing, the vertical mattress suture group (2.3 ± 0.2 mm) showed less mean displacement than did the vertical FasT-Fix or the Viper system groups (3.9 ± 0.7 mm and 3.9 ± 0.5 mm, respectively); the vertical mattress suture group (21.8 ± 2 N/mm) also displayed superior mean stiffness to the vertical FasT-Fix or the Viper system groups (13.2 ± 2 N/mm and 13.1 ± 1.8 N/mm, respectively). During load-to-failure testing, the vertical FasT-Fix group (145.9 ± 9 N) withstood greater mean loads than did the Viper system group (111.2 ± 30 N), but it did not differ significantly from loads withstood by the vertical mattress suture group (133.4 ± 10 N). The Viper system and vertical FasT-Fix groups (14.6 ± 2 N/mm and 12.1 ± 1 N/mm, respectively) displayed superior mean stiffness to the vertical mattress suture group (9.8 ± 0.5 N/mm) during load-to-failure testing. Clinical Relevance Standard vertical mattress sutures provided superior fixation during cyclic loading compared with the 2 all-inside methods of suture fixation, suggesting a potential for better meniscal lesion healing with vertical mattress sutures when confronted with the stresses associated with early, progressive rehabilitation activities. Stronger sutures and less meniscal segment purchase in tears located 3 to 4 mm from the periphery may contribute to the failure of the Viper repair system.

Reducing pressure ulcer incidence in a long-term setting

The results of this study highlight a clear difference between the superior pressure reduction offered by the visco-elastic mattress, Pressurease, compared with that of a standard mattress. The primary objective of the study was to determine whether the mattress could reduce pressure ulcers in a high-risk group of people, rather than determine the impact of the mattress in healing existing damage. However, seven of the participants were noted on day one to have existing damage which improved during the trial. The authors point out that those with the highest Waterlow scores were not necessarily those with the most severe damage. This demonstrates the importance of clinical assessment, in addition to risk assessment, when determining how equipment resources are best used.