Pressurized pyrolysis of mattress residue: An alternative to landfill management

Mattresses are a difficult waste to manage in landfills due to their large volume and low density. Pyrolysis treatment could reduce its volume while producing fuel or products valuable for the chemical industry. Pressurized pyrolysis at 400, 450, and 500 °C is carried out in a lab-scale autoclave at initial pressures 4.2, 8.4, and 16.8 bar. Product gas yield increases slightly along with elevated pressure as well as temperature. However, beyond 8.4 bar the initial pressure makes no discernible differences. CO and CO2 are the major gas species followed by CH4. CO contributes the most to the product gas energy content followed by C3 species, C2H6, and H2. Calculated energy content (heating value) is between 2 and 15 MJ·Nm-3. In terms of product gas energy content, low pressure pyrolysis is favorable over high pressure pyrolysis. According to integration areas of chromatographic measurements the liquid phase contains up to 25 % of N-compounds, with benzonitrile being the most abundant, followed by toluene, o-xylene, and ethylbenzene. The solid char maintains constant properties across operating conditions, with carbon and energy contents of approximately 75 wt% and 30 MJ·kg-1, respectively.

Dosimetric characterization of foam padding with posterior fields in palliative radiation therapy

Patients undergoing external beam radiation therapy for the palliative treatment of painful bony metastases may have difficulty maintaining a still position on a rigid uncovered couch top, both during CT simulation as well as during patient setup, image guidance, and treatment on the linear accelerator. For these patients, a thin foam pad or mattress is sometimes used to mitigate patient discomfort. It was desired to quantify the effect of the padding in cases in which the patient is to be treated supine with posterior beams when the majority of the beam weighting traverses both the couch and the pad. Ion chamber measurements in-phantom were acquired with 6 MV, 10 MV, and 15 MV photon beams. At depths of maximum dose, the pad resulted in a difference of signal collected ≤1%. At the phantom surface, the pad resulted in an increase in signal ranging from 1% to 6.5% for the measured beams. CT data of the pad, both with and without applied pressure, indicated that the pad had average HU values close to air.

The experience of using a hospital bed alternative at home among individuals with spinal cord injury: A case series

OBJECTIVE

To inform clinicians' equipment recommendations by characterizing the experiences, skin integrity, and interface pressures in a series of recently discharged individuals with spinal cord injury (SCI) who chose to use an alternative adjustable bed system at home rather than a standard of care hospital bed with mattress overlay.

DESIGN

Mixed methods, observational case series.

SETTING

Community based.

METHODS

Four individuals with cervical SCIs and one partner of a participant with SCI completed interviews about their experiences using an alternative adjustable bed system and their skin health. Participants also underwent pressure mapping on their alternative adjustable bed system and on a standard of care hospital bed with mattress overlay. Interview themes were identified using a consensus qualitative approach. Pressure readings at the sacrum and ischial tuberosities in supine and at the greater trochanter in side lying were compared between surfaces.

OUTCOME MEASURES

Semi-structured interview, questionnaire, and pressure mapping.

RESULTS

All participants reported positive experiences utilizing an alternative adjustable bed system and no episodes of bed-related skin breakdown. Reasons for wanting an alternative adjustable bed included a greater sense of normalcy and larger size. Participants perceived their alternative beds to be comfortable, and to have features that aided their function and assisted their caregivers. Features used included head of bed elevation, height elevation, and bed rails. All participants had clinically acceptable pressure mapping patterns on the alternative adjustable bed system.

CONCLUSION

An adjustable bed system, combined with other skin protection strategies, may be appropriate for certain individuals with spinal cord injury.

Occurrence and risk assessment of five kinds of antimicrobial in mattress on swine farm use ectopic fermentation systems in Zhejiang Province

Mattress is among the main products of ectopic fermentation system (EFS); however, the research on the data of antimicrobial residues in the mattress of EFS and risk assessments of mattress have not been conducted. This study involved a scale survey to assess the levels and distributions of 54 antimicrobial residues, including 4 tetracyclines, 19 quinolones, 22 sulfonamides, 3 amphenicols, and 6 macrolides in mattress on 12 swine farms that use ectopic fermentation systems (EFS) in Zhejiang Province. A total of 25 antimicrobials were detected in mattress, and the total residue amount of antimicrobial in mattress samples of each farm was 0.77-28.2 g/T. Chlortetracycline had the highest contribution rate, and the residue amount of antimicrobial in mattress is not entirely determined by the start-up time of EFS but is related to the use of feed containing antimicrobial, medication habits, the level of mattress management, and maintenance methods of EFS. The risk assessments of antimicrobial in the mattress were carried out. The results show that the risk of using mattress of EFS for soil is low.

What type of mattress should be chosen to avoid back pain and improve sleep quality? Review of the literature

Energy spent during daily activities is recuperated by humans through sleep, ensuring optimal performance on the following day. Sleep disturbances are common: a meta-analysis on sleep quality showed that 15–30% of adults report sleep disorders, such as sleep onset latency (SOL), insufficient duration of sleep and frequently waking up at night. Low back pain (LBP) has been identified as one of the main causes of poor sleep quality. Literature findings are discordant on the type of mattress that might prevent onset of back pain, resulting in an improved quality of sleep. We conducted a systematic literature review of articles published until 2019, investigating the association of different mattresses with sleep quality and low back pain. Based on examined studies, mattresses were classified according to the European Committee for Standardization (2000) as: soft, medium-firm, extra-firm or mattresses customized for patients affected by supine decubitus. A total of 39 qualified articles have been included in the current systematic review. Results of this systematic review show that a medium-firm mattress promotes comfort, sleep quality and rachis alignment.

About some factors influencing safety mattress performances in head impact collisions: A pilot study

OBJECTIVES

In recreational snow sports activities, safety mattresses are placed on obstacles to prevent injuries from a collision with users. However, the performances of these devices in field conditions remain unclear. The objective of this study is to evaluate the effect of mattress thickness, impact speed, impacting mass and atmospheric conditions on head acceleration during an in-field impact on safety mattress.

DESIGN

42 in-field experimental drop tests of a normative metallic head were conducted on safety mattress to assess the influence of impact speed (5.8m/s or 7.3m/s), impacting mass (6kg or 11.6kg), outside conditions (3 conditions) and mattress thickness (24cm, 32cm, 44cm) on head acceleration at impact.

METHODS

Linear accelerations were measured and Head Injury Criteria 15ms (HIC₁₅) was computed. A statistical analysis (ANOVA) was used to characterize the effects of the varying parameters on maximal acceleration and HIC₁₅.

RESULTS

Reduced impact speed, increased mattress thickness and change in the outside conditions significantly decreased the head acceleration and HIC₁₅ (p<0.001). The effect of the impacting mass on head acceleration was not significant.

CONCLUSIONS

This study highlights the influence of impact speed, atmospheric condition and mattress construction on absorption capacities of safety mattresses. It is a first step toward a better understanding and evaluation of safety mattresses performances.

Evaluation of X-ray table mattresses for radiation attenuation and impact on image quality

INTRODUCTION

Mattresses in the radiology department tend to be an overlooked aspect of imaging equipment. This paper evaluates the radiation attenuation characteristics of mattresses and the effect they have on image quality.

METHODS

Thirteen mattresses (from new to 20 years of age) were evaluated. Incident air kerma (IAK) was measured in two conditions, with and without mattress over a range of exposure factors using a digital dosimeter. Image quality was assessed by calculating the inverse image quality factor (IQF_inv) using a commercially available phantom (CDRAD) for the same exposure factors. The correlation of age and attenuation and image quality was calculated.

RESULTS

Measured IAK and image quality was affected by the addition of a mattress with older mattresses having greater attenuation; there is a moderate/large correlation (0.38-0.51) between age and IAK. IQF_inv deteriorated with the addition of a mattress but there was no correlation with age (-0.41 to 0.16). Clinically, there is no impact of any mattress in the study as changes to the exposure factors to account for the attenuation are smaller than the increments in mAs available on X-ray equipment.

CONCLUSION

The results indicate that while the presence of a mattress does impact on transmitted radiation and the quality of the image, the clinical impact is insignificant. Attenuation correlates with age but with no clinical significance. There is no correlation between age and image quality.

IMPLICATIONS FOR PRACTICE

Quality control tests for attenuation and impact on image quality are not required in clinical practice. The method could be used by manufacturers to test new materials and mattresses and could provide users with specifications of new products.

Sleeping mattress determinants and evaluation: a biomechanical review and critique

Background

Sleeping mattress parameters significantly influence sleeping comfort and health, as reflected by the extensive investigations of sleeping support biomechanics to prevent sleep-related musculoskeletal problems.

Methodology

Herein, we review the current trends, research methodologies, and determinants of mattress biomechanics research, summarizing evidence published since 2008. In particular, we scrutinize 18 articles dealing with the development of new designs, recommendation criteria, instruments/methods of spine alignment evaluation, and comparative evaluation of different designs.

Results

The review demonstrated that mattress designs have strived for customization, regional features, and real-time active control to adapt to the biomechanical features of different body builds and postures. However, the suggested threshold or target values for desirable spine alignment and body pressure distribution during sleep cannot yet be justified in view of the lack of sufficient evidence.

Conclusions

It is necessary to formulate standard objectives and protocols for carrying out mattress evaluation.

Reducing the impact of intensive care unit mattress compressibility during CPR: a simulation-based study

BACKGROUND

The depth of chest compression (CC) during cardiac arrest is associated with patient survival and good neurological outcomes. Previous studies showed that mattress compression can alter the amount of CCs given with adequate depth. We aim to quantify the amount of mattress compressibility on two types of ICU mattresses and explore the effect of memory foam mattress use and a backboard on mattress compression depth and effect of feedback source on effective compression depth.

METHODS

The study utilizes a cross-sectional self-control study design. Participants working in the pediatric intensive care unit (PICU) performed 1 min of CC on a manikin in each of the following four conditions: (i) typical ICU mattress; (ii) typical ICU mattress with a CPR backboard; (iii) memory foam ICU mattress; and (iv) memory foam ICU mattress with a CPR backboard, using two different sources of real-time feedback: (a) external accelerometer sensor device measuring total compression depth and (b) internal light sensor measuring effective compression depth only. CPR quality was concurrently measured by these two devices. The differences of the two measures (mattress compression depth) were summarized and compared using multilevel linear regression models. Effective compression depths with different sources of feedback were compared with a multilevel linear regression model.

RESULTS

The mean mattress compression depth varied from 24.6 to 47.7 mm, with percentage of depletion from 31.2 to 47.5%. Both use of memory foam mattress (mean difference, MD 11.7 mm, 95%CI 4.8-18.5 mm) and use of backboard (MD 11.6 mm, 95% CI 9.0-14.3 mm) significantly minimized the mattress compressibility. Use of internal light sensor as source of feedback improved effective CC depth by 7-14 mm, compared with external accelerometer sensor.

CONCLUSION

Use of a memory foam mattress and CPR backboard minimizes mattress compressibility, but depletion of compression depth is still substantial. A feedback device measuring sternum-to-spine displacement can significantly improve effective compression depth on a mattress.

TRIAL REGISTRATION

Not applicable. This is a mannequin-based simulation research.

Age and sex differences in bedroom habits and bedroom preferences

OBJECTIVE

The objective of this study was to estimate the prevalence of different bedroom habits/preferences, and to assess whether these habits/preferences differ with age and sex.

METHODS

A population-based Norwegian cross-sectional telephone survey with 1001 of 1599 randomly selected adults (63% response rate) was performed. The questions about habits and preferences had different response alternatives (yes/no; up to eight response alternatives). Mean age was 47.5 years, and split into four groups (18-29, 30-44, 45-59, 60+ years). Age and sex differences were explored with chi-square statistics.

RESULTS

Electronic media use in bed after bedtime was more common in younger compared to older age groups, with no sex difference. Daily use was reported by 61.8% of participants aged 18-29 years, compared to 3.7% among participants of 60+ years. Reading in bed after bedtime was more common with increasing age, and more common among females compared to males. Females and older participants more often rated their bed as very good. The older the participants, the colder the reported bedroom temperature. During winter, 48.5% of participants aged 60+ years reported a bedroom temperature of ≤12 °C. Many participants (39.2%) reported having their bedroom window always open at night, with no sex difference, but an increase with increasing age. Blackout curtains were used by 63.3%, with a drop in use with increasing age. Most participants preferred lying on the side when trying to sleep. Fewer older compared to younger participants preferred lying on the stomach.

CONCLUSIONS

The findings may stimulate further studies exploring whether these habits/preferences may influence sleep and sleep disorders.

The effect of human-mattress interface's temperature on perceived thermal comfort

In recent years, methods that allow for an objective evaluation of perceived comfort, in terms of postural, physiological, cognitive and environmental comfort, have received a great deal of attention from researchers. This paper focuses on one of the factors that influences physiological comfort perception: the temperature difference between users and the objects with which they interact. The first aim is to create a measuring system that does not affect the perceived comfort during the temperatures' acquisition. The main aim is to evaluate how the temperature at the human-mattress interface can affect the level of perceived comfort. A foam mattress has been used for testing in order to take into account the entire back part of the human body. The temperature at the interface was registered by fourteen 100 Ohm Platinum RTDs (Resistance Temperature Detectors) placed on the mattress under the trunk, the shoulders, the buttocks, the legs, the thighs, the arms and the forearms of the test subject. 29 subjects participated in a comfort test in a humidity controlled environment. The test protocol involved: dress-code, anthropometric-based positioning on mattress, environment temperature measuring and an acclimatization time before the test. At the end of each test, each of the test subject's thermal sensations and the level of comfort perception were evaluated using the ASHRAE (American Society of Heating, Refrigerating and Air-Conditioning Engineers) scale. The data analyses concerned, in the first instance, correlations between the temperature at the interface and comfort levels of the different parts of the body. Then the same analyses were performed independently of the body parts being considered. The results demonstrated that there was no strong correlation among the studied variables and that the total increase of temperature at interface is associated with a reduction in comfort.

Decreasing Clostridium difficile health care-associated infections through use of a launderable mattress cover

BACKGROUND

The annual incidence of Clostridium difficile infection (CDI) in the United States is estimated to be 330,000 cases. We evaluated the impact of using a launderable mattress and bed deck cover on the incidence of hospital-onset CDI in 2 long-term acute care hospitals (LTACHs).

METHODS

Two LTACHs began using a launderable mattress and bed deck cover on beds starting in May 2013. One facility had 74 beds, and the other had 30 beds. Covers were changed after every patient. The covers were laundered using hot water, detergent, and chlorine. Rates for CDIs were compared using Poisson regression between the 16 months before use of the launderable cover and the 14 months after the cover started being used.

RESULTS

At hospital A, the use of bedcovers reduced the rate of infection by 47.8% (95% confidence interval [CI], 47.1-48.6), controlling for the rate of handwashing compliance and length of stay in days. At hospital B, the use of bedcovers reduced the rate of infection by 50% (95% CI, 47.5-52.7), controlling for the rate of handwashing compliance and length of stay in days.

CONCLUSION

The use of a launderable cover for mattresses and bed decks of hospital beds was associated with a decreased rate of health care-associated CDI in 2 LTACHs.

A 6 month evaluation of a non-powered hybrid mattress replacement system

In 2013, the Royal Cornwall Hospitals NHS Trust undertook a 6-week evaluation of the AtmosAir 4000 non-powered reactive pressure redistribution mattress replacement system to determine its suitability in supporting the prevention of pressure ulcers in high-risk patients (phase one). The results demonstrated that the AtmosAir 4000 mattress system, together with skin assessment and repositioning regimes, met the pressure ulcer preventative needs of patients at high and very high risk of developing pressure ulcers. It also resulted in a notable reduction in the use of dynamic air mattresses. Consequently, 50 AtmosAir 4000 mattresses were purchased for two acute medical wards in the evaluation site, where the majority of patients are elderly with an acute medical condition. This article discusses the second phase where an audit compares the number of hospital-acquired pressure ulcers reported over a 6-month period with the equivalent time period in 2014. Results show that the number of pressure ulcers reduced by 65% and 50% in the two wards. The number of dynamic mattresses used on the two wards reduced significantly from 28 to 7, which represents a 75% reduction in usage.

Effects of an adapted mattress in musculoskeletal pain and sleep quality in institutionalized elders

We aimed to evaluate the impact in sleep quality and musculoskeletal pain of a Medium-Firm Mattress (MFM), and their relationship with objective sleep parameters in a group of institutionalized elders. The sample size included forty older adults with musculoskeletal pain. We did a clinical assessment at baseline and weekly trough the study period of four weeks. We employed the Pittsburgh Sleep Quality Index (PSQI) and Pain Visual Analog Scale (P-VAS). Additionally a sub-group of good sleepers, selected from PSQI baseline evaluation, were studied with actigraphy and randomized to MFM or High Firm Mattress (HFM), in two consecutive nights. We found a significant reduction of cervical, dorsal and lumbar pain. PSQI results did not change. The actigraphy evaluation found a significant shorter sleep onset latency with MFM, and a slightly better, but not statistically significant, sleep efficiency. The medium firmness mattress improved musculoskeletal pain and modified the sleep latency.

Forensic analysis of crib mattress properties on pediatric CPR quality--can we balance pressure reduction with CPR effectiveness?

INTRODUCTION

Single mode, pressure reduction (PR) crib mattresses are increasingly employed in hospitals to prevent skin injury and infection. However, single mode PR mattresses risk large mattress deflection during CPR chest compressions, potentially leading to inadequate chest compressions.

HYPOTHESIS

New, dual mode PR crib mattress technology provides less mattress deflection during chest compressions (CCs) with similar PR characteristics for prevention of skin injury.

METHODS

Epochs of 50 high-quality CCs (target sternum-spine compression depth ≥ 38 mm) guided by real-time force/deflection sensor (FDS) feedback were delivered to CPR manikin with realistic CC characteristics on two PR crib mattresses for four conditions: (1) single mode+backboard; (2) dual mode+backboard; (3) single mode-no backboard; and (4) dual mode-no backboard. Mattress displacement was measured using surface reference accelerometers. Mattress displacement ≥ 5 mm was prospectively defined as minimal clinically important difference. PR qualities of both mattresses were assessed by tissue interface pressure mapping.

RESULTS

During simulated high quality CC, single mode had significantly more mattress displacement compared to dual mode (mean difference 16.5 ± 1.4mm, p<0.0001) with backboard. This difference was greater when no backboard was used (mean difference 31.7 ± 1.5mm, p<0.0001). Both single mode and dual mode met PR industry guidelines (mean surface pressure <50 mm Hg).

CONCLUSIONS

Chest compressions delivered on dual mode pressure reduction crib mattresses resulted in substantially smaller mattress deflection compared to single mode pressure reduction mattresses. Skin pressure reduction qualities of dual mode pressure reduction crib mattress were maintained. We recommend that backboards continue to be used in order to mitigate mattress deflection during CPR on soft mattresses.