Positron emission tomography study of effects of two pressure-relieving support surfaces on pressure ulcer development

Efficacy of D33 Sealed Foam in Preventing Skin Injury from Surgical Positioning: Randomized Clinical Trial

Objective: To evaluate the efficacy of density-33 (D33) sealed foam in preventing skin injuries from surgical positioning. Approach: The study, reported according to the Consolidated Standards of Reporting Trials, is characterized as a randomized clinical trial, double mask, with 64 adult patients undergoing elective surgery, 35 allocated to the control group (CG), positioned on a conventional surgical table, and 29 to the experimental group (EG), positioned on a conventional surgical table overlaid with a D33 sealed foam support surface (SS) in the occipital, sacral, and heel regions. Simple randomization was carried out, as was masking of the researcher who evaluated the skin of the patient and the statistician. Data collection was carried out immediately preoperatively, intraoperatively, and postoperatively until the third day or until patient discharge. Statistical analysis included measures of association in contingency tables, χ2, and relative risk to compare the incidence of injuries between groups. Results: Skin injuries were greater in the CG, with blanchable erythema being the main injury. The use of D33 sealed foam reduced the incidence of injury in the EG by 61.2% (relative risk: 0.39; 95% confidence interval: 0.220-0.684; p < 0.001). Innovation: One of the first clinical studies to demonstrate that using a D33 sealed foam SS decreased the incidence of blanchable erythema from surgical positioning. Conclusion: D33 sealed foam was effective in preventing skin injury from surgical positioning in patients undergoing elective surgeries.

Differentiating Pressure Ulcer Risk Levels through Interpretable Classification Models Based on Readily Measurable Indicators

Pressure ulcers carry a significant risk in clinical practice. This paper proposes a practical and interpretable approach to estimate the risk levels of pressure ulcers using decision tree models. In order to address the common problem of imbalanced learning in nursing classification datasets, various oversampling configurations are analyzed to improve the data quality prior to modeling. The decision trees built are based on three easily identifiable and clinically relevant pressure ulcer risk indicators: mobility, activity, and skin moisture. Additionally, this research introduces a novel tabular visualization method to enhance the usability of the decision trees in clinical practice. Thus, the primary aim of this approach is to provide nursing professionals with valuable insights for assessing the potential risk levels of pressure ulcers, which could support their decision-making and allow, for example, the application of suitable preventive measures tailored to each patient's requirements. The interpretability of the models proposed and their performance, evaluated through stratified cross-validation, make them a helpful tool for nursing care in estimating the pressure ulcer risk level.

The biomechanical efficacy of a dressing with a soft cellulose fluff core in protecting prone surgical patients from chest injuries on the operating table

Pressure ulcers are soft‐tissue damage associated with tissue exposure to sustained deformations and stress concentrations. In patients who are proned for ventilation or surgery, such damage may occur in the superficial chest tissues that are compressed between the rib cage and the support surface. Prophylactic dressings have been previously proven as generally effective for pressure ulcer prevention. In this study, our goal was to develop a novel computational modelling framework to investigate the biomechanical efficacy of a dressing with a soft cellulose fluff core in protecting proned surgical patients from chest pressure ulcers occurring on the operating table, due to body fixation by the Relton‐Hall frame. We compared the levels of mechanical compressive stresses developing in the soft chest tissues, above the sternum and ribs, due to the trunk weight, whilst the body is supported by the Relton‐Hall frame pads, with versus without the prophylactically applied bilateral dressings. The protective efficacy index for the extremely high stresses, above the 95th‐percentile, were 40.5%, 25.6% and 24.2% for skin, adipose and muscle, respectively, indicating that the dressings dispersed elevated soft‐tissue stresses. The current results provide additional support for using soft cellulose fluff core dressings for pressure ulcer prophylaxis, including during surgery.

Computational studies of the biomechanical efficacy of a minimum tissue deformation mattress in protecting from sacral pressure ulcers in a supine position

Sustained soft tissue exposure to localised deformations is a trigger for the formation of pressure ulcers. Immersion and envelopment are critical benchmarks that determine comfort and the pressure ulcer risk mitigation, as they have considerable influence on tissue stress concentrations near bony prominences. In the present study, we developed a computer modelling framework for quantifying the extent by which optimal envelopment disperses tissue stress concentrations near the sacrum. To compare the risk of developing a sacral pressure ulcer while lying supine on a regular foam mattress with respect to lying on a specialised, minimum tissue deformation mattress (which closely conforms to the body contours), we used a three‐dimensional anatomically‐realistic model of the adult female buttocks. The strains and stresses in the subdermal soft tissues reached peak values of 65% and 2.4 kPa for the regular mattress, respectively, but always remained below 45% and 1.2 kPa for the minimum tissue deformation mattress, which indicates longer safe times for supine support on the latter mattress. Our work demonstrates that alleviation of localised, sustained stress concentrations through good immersion and envelopment of the support surface protects from pressure ulcers, and has the potential to relieve chronic pain which is associated with the pressure ulcer risk.