Subepidermal moisture detection of heel pressure injury: The pressure ulcer detection study outcomes

The utility of skin surface temperature measurement in the prediction of diabetic foot ulceration

AIM

Temperature is a marker of inflammation. Research has shown that by measuring skin surface temperature in those with a history of diabetic foot ulceration (DFU), tissue damage can be identified early and reduce rates of subsequent DFU. This study considered whether measuring skin surface temperature using infra-red thermometry can identify early tissue damage and inform clinical practice in a general population with Diabetes Mellitus (DM).

METHOD

The data presented was taken from a prospective observational study of risk factors in patients with Diabetes. As part of this study, temperature measurements using the Flir E6 Infra-red camera were taken from 216 individuals attending outpatient diabetes clinics in a large urban teaching hospital in Ireland as part of a comprehensive diabetic foot assessment. Measurements were taken at foot sites associated with increased risk at baseline received repeat temperature measurement on 2 subsequent occasions in the following week. Any ulceration was subsequently recorded.

RESULTS

Discussion: Of the 216 participants, 4 % (n = 9) developed visual ulceration within 7 days. All of these had been identified at high risk at baseline assessment and had a history of foot disease. A temperature differential of ≥2.2 °C between sites of interest was recorded. Temperature ranges varied from 29.1 °C to 37.6 °C. High temperature was considered if over 35 °C. Of those who developed a diabetic foot ulceration within the 7 day follow up period, 78 % (n = 7) had a high temperature. The remaining 22 % (n = 2) who developed ulceration had a temperature reading in the normal range.

CONCLUSION

Elevated skin surface temperature was seen prior to the development of DFU in all cases in this study. Initial analysis suggests that neither the 35 °C threshold nor a 2.2 °C temperature difference is indicative of inevitable tissue damage in this population due to the high number of false positives seen.

Integrating technologies to enhance risk assessment for the early detection and prevention of pressure ulcers

Pressure ulcers (PU) are a globally recognised healthcare concern, with their largely preventable development prompting the implementation of targeted preventive strategies. Risk assessment is the first step to planning individualised preventive measures. However, despite the long use of risk assessment, and the >70 risk assessment tools currently available, PUs remain a significant concern. Various technological advancements, including artificial intelligence, subepidermal moisture measurement, cytokine measurement, thermography and ultrasound are emerging as promising tools for PU detection, and subsequent prevention of more serious PU damage. Given the rise in availability of these technologies, this advances the question of whether our current approaches to PU prevention can be enhanced with the use of technology. This article delves into these technologies, suggesting that they could lead healthcare in the right direction, toward optimal assessment and adoption of focused prevention strategies.

Biomarkers of local inflammation at the skin's surface may predict both pressure and diabetic foot ulcers

This commentary considers the similarities which exist between pressure ulcers (PUs) and diabetic foot ulcers (DFUs). It aims to describe what is known to be shared-both in theory and practice-by these wound types. It goes on to detail the literature surrounding the role of inflammation in both wound types. PUs occur following prolonged exposure to pressure or pressure in conjunction with shear, either due to impaired mobility or medical devices. As a result, inflammation occurs, causing cell damage. While DFUs are not associated with immobility, they are associated with altered mobility occurring as a result of complications of diabetes. The incidence and prevalence of both types of lesions are increased in the presence of multimorbidity. The prediction of either type of ulceration is challenging. Current risk assessment practices are reported to be ineffective at predicting when ulceration will occur. While systemic inflammation is easily measured, the presence of local or subclinical inflammation is harder to discern. In patients at risk of either DFUs or PUs, clinical signs and symptoms of inflammation may be masked, and systemic biomarkers of inflammation may not be elevated sufficiently to predict imminent damage until ulceration appears. The current literature suggests that the use of local biomarkers of inflammation at the skin's surface, namely oedema and temperature, may identify early tissue damage.

Decreasing Intraoperative Skin Damage in Prone-Position Surgeries

OBJECTIVE

To determine if subepidermal moisture (SEM) measures help detect and prevent intraoperative acquired pressure injuries (IAPIs) for prone-position surgery.

METHODS

In this clinical trial of patients (n = 39 preintervention, n = 48 intervention, 100 historical control) undergoing prone-position surgery, researchers examined the use of multidimensionally flexible silicone foam (MFSF) dressings applied preoperatively to patients' face, chest, and iliac crests. Visual skin assessments and SEM measures were obtained preoperatively, postoperatively, and daily for up to 5 days or until discharge. Electronic health record review included demographic, medical, and surgery data.

RESULTS

Of the 187 total participants, 76 (41%) were women. Participants' mean age was 61.0 ± 15.0 years, and 9.6% were Hispanic (n = 18), 9.6% were Asian (n = 18), 6.9% were Black or African American (n = 13), and 73.8% were White (n = 138). Participants had a mean Scott-Triggers IAPI risk score of 1.5 ± 1.1. Among those with no erythema preoperatively, fewer intervention participants exhibited postoperative erythema on their face and chest than did preintervention participants. Further, fewer intervention participants had SEM-defined IAPIs at all locations in comparison with preintervention participants. The MFSF dressings overcame IAPI risk factors of surgery length, skin tone, and body mass index with fewer IAPIs in intervention participants.

CONCLUSIONS

Patients undergoing prone-position surgeries developed fewer IAPIs, and SEM measures indicated no damage when MFSF dressings were applied to sites preoperatively. The SEM measures detected more damage than visual assessment.

Shedding new light for nurses: Enhancing pressure injury prevention across skin tones with sub-epidermal moisture assessment technology

AIM(S)

To assess the effectiveness of sub-epidermal moisture (SEM) assessment technology in the detection of early-stage pressure damage in a critical care unit (CCU) and dark skin tone patients and its impact on hospital-acquired pressure injury (HAPI) incidence.

DESIGN

Quality improvement study employing Kurt Lewin's change model emphasizing planning, implementation, evaluation and sustainable change.

METHODS

The study evaluated 140 adult patients admitted to the CCU over a 24-week period, from July to December 2022. Retrospective analysis of standard PI care pathways was performed in 90 patients admitted during a 12-week pre-implementation period. Fifty patients were admitted through the subsequent 12-week implementation period. SEM assessments were performed daily at the sacrum and heels and interventions were applied based on SEM assessments; SEM delta ≥0.6 indicating localized oedema or persistent focal oedema. Statistical analyses were performed on anonymized data.

RESULTS

Pre-implementation HAPI incidence was 8.9% (N = 8/90). All eight patients were African American with varying skin tones. A 100% reduction in HAPI incidence was achieved in the implementation period which included 35 African American patients. The relative risk of HAPI incidence was 1.6 times higher in the pre-implementation group.

CONCLUSION

Implementing SEM assessment technology enabled equitable PI care for all population types and resulted in a 100% reduction of PIs in our CCU. Objective SEM assessments detected early-stage PIs, regardless of skin tone and enabled providing interventions to specific anatomies developing tissue damage as opposed to universal preventive interventions.

IMPLICATIONS

PI care pathways relying on visual and tactile skin assessments are inherently biased in providing equitable care for dark skin tone patients. Implementing SEM assessments empowers healthcare practitioners in driving objective clinical interventions, eliminates bias and enables positive PI health outcomes.

IMPACT

Implementing SEM assessment technology had three main effects: it detected early tissue damage regardless of skin tone (detection effect), enabled anatomy-specific interventions (treatment effect) and prevented PIs across all population types (prevention effect). The authors have adhered to the Standards for Quality Improvement Reporting Excellence (SQUIRE) 2.0 guidelines.

PATIENT OR PUBLIC CONTRIBUTION

No patient or public contribution. What does this paper contribute to the wider global clinical community? Addressing health inequities in pressure injury prevention; Demonstrated effectiveness across patient populations; Resource optimization and enhanced patient safety.

Prevalence and incidence of pressure injuries among older people living in nursing homes: A systematic review and meta-analysis

BACKGROUND

Pressure injuries are a fundamental safety concern in older people living in nursing homes. Recent studies report a disparate body of evidence on pressure injury prevalence and incidence in this population.

OBJECTIVES

To systematically quantify the prevalence and incidence of pressure injuries among older people living in nursing homes, and to identify the most frequently occurring PI stage(s) and anatomical location(s).

DESIGN

Systematic review and meta-analysis.

SETTING(S)

Nursing homes, aged care, or long-term care facilities.

PARTICIPANTS

Older people, 60 years and older.

METHODS

Cross-sectional and cohort studies reporting on either prevalence or incidence of pressure injuries were included. Studies published in English from 2000 onwards were systematically searched in Medline, PubMed, Embase, Cochrane Library, CINAHL and ProQuest. Screening, data extraction and quality appraisal were undertaken independently by two or more authors and adjudicated by another. Outcomes included pressure injury point prevalence, cumulative incidence, and nursing home acquired pressure injury rate. In meta-analyses, Cochrane's Q test and the I2 statistic were used to explore heterogeneity. Random effects models were used in the presence of substantial heterogeneity. Sources of heterogeneity were investigated by subgroup analyses and meta-regression.

RESULTS

3384 abstracts were screened, and 47 full-text studies included. In 30 studies with 355,784 older people, the pooled pressure injury prevalence for any stage was 11.6 % (95 % CI 9.6-13.7 %). Fifteen studies with 5,421,798 older people reported the prevalence of pressure injury excluding stage I and the pooled estimate was 7.2 % (95 % CI 6.2-8.3 %). The pooled incidence for pressure injury of any stage in four studies with 10,645 older people was 14.3 % (95 % CI 5.5-26.2 %). Nursing home acquired pressure injury rate was reported in six studies with 79,998 older people and the pooled estimate was 8.5 % (95 % CI 4.4-13.5 %). Stage I and stage II pressure injuries were the most common stages reported. The heel (34.1 %), sacrum (27.2 %) and foot (18.4 %) were the three most reported locations of pressure injuries. Meta-regression results indicated a reduction in pressure injury prevalence over the years of data collection.

CONCLUSION

The burden of pressure injuries among older people in nursing homes is similar to hospitalised patients and requires a targeted approach to prevention as is undertaken in hospitals. Future studies using robust methodologies focusing on epidemiology of pressure injury development in older people are needed to conduct as the first step of preventing pressure injuries.

REGISTRATION NUMBER

PROSPERO CRD42022328367.

TWEETABLE ABSTRACT

Pressure injury rates in nursing homes are comparable to hospital rates indicating the need for targeted programmes similar to those in hospitals.

Medical Applications of Skin Tissue Dielectric Constant Measurements

Tissue dielectric constant (TDC) values assess certain skin properties that are dependent on multiple factors but mainly on the relative amount of water content within a locally measured tissue volume. Because of the non-invasive nature of these measurements and their ease of use, the method has been widely used in various medically related applications. The goal of this paper was to review and describe the uses and findings of such TDC measurements, considering and including the wide array of medical applications. The review is in part based on information derived from an analysis of published material obtained via literature searches of four major electronic databases and, in part, based on the author's experience with the TDC measurement methods and their various applications and his professional experiences. The databases searched were PubMed, Web of Science, EMBASE, and CINAHL Complete. Based on the initial search criteria, a total of 1257 titles were identified. After removing duplicates and filtering according to relevancy, 160 remained for detailed further review. In some cases, the bibliography of these retrieved articles provided additional sources. The findings demonstrate multiple research and medical uses and applications of TDC measurements, focusing on detecting and quantifying localized edema and lymphedema in multiple target sites. These include the upper and lower extremities, breasts, and trunk as regions involved in medical conditions causing lymphedema. In addition, the findings suggest that TDC evaluations are a convenient, non-invasive method to study and evaluate other conditions impacting skin, including diabetes mellitus and skin wounds or ulcers. Its ability to detect aspects of tissue changes simply and rapidly at almost any anatomical location makes it a useful tool for investigating multiple dermatological conditions and their treatment as future applications of this method.

Current Perspectives on Pressure Injuries in Persons with Dark Skin Tones from the National Pressure Injury Advisory Panel

BACKGROUND

Pressure injury (PI) development is multifactorial. In patients with dark skin tones, identifying impending PIs by visual skin assessment can be especially challenging. The need for improved skin assessment techniques, especially for persons with dark skin tones, continues to increase. Similarly, greater awareness of the need for inclusivity with regard to representation of diverse skin colors/tones in education materials is apparent.

OBJECTIVE

To provide current perspectives from the literature surrounding skin assessment and PI development in patients with dark skin tones.

METHODS

The following elements will be discussed through the lens of skin tone: (1) historical perspectives of PI staging from the National Pressure Injury Advisory Panel, (2) epidemiology of PI, (3) anatomy and physiology of the skin, (3) skin tone assessment and measurement, (4) augmented visual assessment modalities, (5) PI prevention, (6) PI healing, (7) social determinants of health, and (8) gaps in clinician education.

CONCLUSIONS

This article highlights the gap in our clinical knowledge regarding PIs in patients with dark skin tones. Racial disparities with regard to PI development and healing are especially clear among patients with dark skin tones. Skin tone color assessment must be standardized and quantifiable in clinical education, practice, and research. This work is urgently needed, and support from private and governmental agencies is essential.

Sub epidermal moisture measurement and targeted SSKIN bundle interventions, a winning combination for the treatment of early pressure ulcer development

This study aimed to investigate the impact of sub epidermal moisture (SEM) measurement and targeted pressure ulcer (PU) prevention, versus visual skin assessment and usual care, on mean SEM delta scores and early pressure ulcer development in acute hospital patients. A quantitative quasi-experimental observational approach was used. A total of 149 at risk acute hospital patients took part, 78 treatment, and 71 control. SEM deltas were recorded daily for a maximum of 5 days using the SEM Scanner (Bruin Biometrics LLC, Los Angeles, California), on three sites: the sacrum, the right heel, and the left heel, with enhanced and targeted PU prevention interventions occurring in those with an elevated SEM delta scores in the treatment group. Intention to treat analysis was used to guide the final composition of results. SEM PU represents PU development as identified by 2 days of sustained abnormal SEM delta scores, ≥0.5, after day one. The mean number of days completed by participants was just under 4 days, participants had many different comorbidities, with the most common being: hypertension, cancer, and chronic obstructive pulmonary disease. Results showed that following the introduction of SEM guided targeted treatments, participants in the treatment group yielded a statistically significant reduction in mean SEM delta scores (MD: 0.49; 95% CI: 0.59, 0.39; P < .0001), and in the odds of developing a SEM PU (OR: 0.59, 95% CI: 0.24 to 1.00; P = .05). In the treatment group, none of the participants developed a visual PU, whereas, in the control group, 1.41% (n = 1/71) developed a visual PU. Based on all the results, the following is concluded, (1). There was a greater reduction in mean SEM delta scores among those cared for using SEM measurement and targeted PU prevention, versus those cared for using visual skin assessment and usual care, and (2). the mean SEM delta scores was statistically significantly lower at the study end for those who received targeted treatments based on abnormal SEM scores. More research is now needed in other and larger at-risk groups to further validate what was found in this study.

Assessment and Identification of Skin Disorders in Skin of Color: An Integrative Review

Skin assessment in patients with dark skin tones (DST) continues to be a challenge for many healthcare providers (HCP) because the visual cues are not always readily identified. For example, identification of early signs of pressure injury when subtle skin color changes are missed has the potential to cause harm and contribute to healthcare disparities. Appropriate wound management can begin only when the wound is correctly identified. For HCPs to identify early signs of skin conditions in DST patients, they must be provided education and effective tools enabling them to identify clinically relevant signs of skin damage in all patients. This article reviews basic anatomy of the skin; it focuses on differences seen in DST and reviews assessment strategies to assist the HCP to identify skin changes and conditions.

Electronic Alert Signal for Early Detection of Tissue Injuries in Patients: An Innovative Pressure Sensor Mattress

Monitoring the early stage of developing tissue injuries requires intact skin for surface detection of cell damage. However, electronic alert signal for early detection is limited due to the lack of accurate pressure sensors for lightly pigmented skin injuries in patients. We developed an innovative pressure sensor mattress that produces an electronic alert signal for the early detection of tissue injuries. The electronic alert signal is developed using a web and mobile application for pressure sensor mattress reporting. The mattress is based on body distributions with reference points, temperature, and a humidity sensor to detect lightly pigmented skin injuries. Early detection of the pressure sensor is linked to an electronic alert signal at 32 mm Hg, a temperature of 37 °C, a relative humidity of 33.5%, a response time of 10 s, a loading time of 30 g, a density area of 1 mA, and a resistance of 7.05 MPa (54 N) at 0.87 m³/min. The development of the innovative pressure sensor mattress using an electronic alert signal is in line with its enhanced pressure detection, temperature, and humidity sensors.

Measuring subepidermal moisture to detect early pressure ulcer development: a systematic review

OBJECTIVE

The aim was to assess evidence related to the measuring of subepidermal moisture (SEM) to detect early, nonvisible development of pressure ulcers (PUs).

METHOD

Using systematic review methodology, all quantitative animal and human research studies written in English were considered. In January 2021, PubMed, CINAHL, SCOPUS, Cochrane and EMBASE databases were searched. The primary outcome of interest was the validity of SEM measurement to detect early PU development. The secondary outcome was time to PU detection, sensitivity and specificity of SEM measurement, and the impact of SEM measurements on PU prevention. Data analysis was undertaken using RevMan and narrative synthesis.

RESULTS

A total of 17 articles met the inclusion criteria. In all studies, a consistent abnormal deviation in SEM measurements corresponded with evidence of visual PU development. Time to PU development, explored in four studies, showed earlier detection of PU development using SEM measurement. RevMan analysis identified the mean difference in time to PU development (SEM measurement versus visual skin assessment, VSA) was 4.61 days (95% confidence interval: 3.94-5.28; p=0.0001) in favour of SEM measurements. The sensitivity of SEM measurements was reported in four studies, and scores varied from 48.3% to 100.0%. Specificity was also reported in four studies and scores ranged from 24.4% to 83.0%. The impact of the detection of abnormal SEM measurements on PU prevention was explored by one study. Results showed a 93% decrease in PU rates when staff acted on the results of the SEM readings.

CONCLUSION

The findings of this review identified that SEM measurement detects PU development earlier than VSA. Furthermore, when staff responded to abnormal SEM measurements, prevention strategies were enhanced, with a subsequent reduction in visible PU development. SEM measurement may therefore be a useful addition to PU prevention strategies.

DECLARATION OF INTEREST

The School of Nursing & Midwifery, RCSI has a research agreement with Bruin Biometrics. Funding for the study was through an Irish Research Council PhD Enterprise Partnership Scheme with Bruin Biometrics. The authors have no other conflicts of interest.

Risk factors for the development and evolution of deep tissue injuries: A systematic review

AIMS

The aim of this systematic review is to identify the current epidemiological evidence indicating the unique risk factors for deep tissue injury (DTI) compared to grade I-IV pressure injury (PI), the proportion of DTI which evolve rather than resolve and the anatomical distribution of DTI.

METHODS

A systematic literature search was undertaken using the MEDLINE and CINAHL Plus databases using the search terms 'Deep tissue injury OR DTI [Title/abstract]'. A google scholar search was also conducted in addition to hand searches of relevant journals, websites and books which were identified from reference lists in retrieved articles. Only peer-reviewed English language articles published 2009-2021 were included, with full text available online.

RESULTS

The final qualitative analysis included nine articles. These included n = 4 retrospective studies, n = 4 prospective studies and n = 1 animal study.

CONCLUSION

The literature indicates that the majority of DTI occur at the heel and sacrum although in paediatric patients they are mainly associated with medical devices. Most DTI are reported to resolve, with between 9.3 and 27% deteriorating to full thickness tissue loss. Risk factors unique to DTI appear to include anaemia, vasopressor use, haemodialysis and nicotine use although it is unclear if these factors are unique to DTI or are shared with grade I-IV PI. Factors associated with deterioration include cooler skin measured using infrared thermography and negative capillary refill. With 100% of DTI showing positive capillary refill in one study resolving without tissue loss (p = 0.02) suggesting this may be an effective prognostic indicator. More prospective studies are required focusing on establishing causal links between risk factors identified in earlier retrospective studies. Ideally these should use statistically powered samples and sufficient follow up periods allowing DTI outcomes to be reached. Further work is also needed to establish reliable diagnostic criteria for DTI in addition to more studies in the paediatric population.

Oedema as a predictor of the incidence of new pressure injuries in adults in any care setting: A systematic review and meta-analysis

BACKGROUND

Oedema measurement, also termed sub-epidermal moisture measurement is recommended as an adjunct pressure injury prevention intervention in international guidelines because it indicates early tissue damage.

OBJECTIVE

To determine the prognostic value of oedema measurement in predicting future pressure injury in adults in any care setting.

DESIGN

Systematic review and meta-analysis.

SETTING

Participants were recruited from nursing homes or aged care facilities, hospitals, or post-acute facilities.

PARTICIPANTS

Adults.

METHODS

A modified 2-week systematic review was undertaken. Study designs included cohort (prospective and retrospective), case-control, case series if relevant comparisons were reported, randomised controlled trials if the association between oedema measurement and pressure injury was reported, and registry data. Databases searched included: Medical Literature Analysis and Retrieval System Online, The Cumulative Index to Nursing and Allied Health Literature, Excerpta Medica and the Cochrane Library from inception to 13 July 2021 with no language restrictions. Screening, data extraction using Checklist for Critical Appraisal and Data Extraction for Systematic Reviews of Prediction Modelling Studies - Prognostic Factors (CHARMS-PF) and quality assessment using Quality in Prognostic Factor Studies (QUIPS) were undertaken independently by ≥2 authors and adjudicated by another if required. Meta-analyses and meta-regression were undertaken. The certainty of the evidence was assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach.

RESULTS

Six studies (n = 483 total) were included. Two studies were set in nursing homes and four in either hospitals or post-acute facilities. Fives studies were prospective cohorts, and one was a randomised control trial. Two studies were assessed as low risk and four studies as moderate risk of bias. The pooled risk ratio in four studies (n = 388) for the relationship between oedema and pressure injury cumulative incidence was 18.87 (95% CI 2.13-38.29) and for time to pressure injury was 4.08 days (95% CI 1.64-6.52). Using GRADE, the certainty of the body of evidence was low for all outcomes. Meta-regression indicated that age, gender, and sample size were poor predictors for the association between oedema and pressure injury.

CONCLUSIONS

Measuring oedema as a predictor for pressure injury development is showing promise but a stronger body of evidence that takes into consideration other prognostic factors is needed to better understand its benefit.

REGISTRATION

PROSPERO CRD42021267834.

TWEETABLE ABSTRACT

Measuring oedema is a promising strategy to prevent pressure injuries but the certainty of evidence for this claim is low.

Sub-epidermal moisture versus traditional and visual skin assessments to assess pressure ulcer risk in surgery patients

OBJECTIVE

To compare the predictive ability of subepidermal moisture (SEM) measurement versus traditional risk assessment and visual skin assessment (VSA) as means of detecting early pressure ulcer (PU) damage development among adults undergoing surgery.

METHOD

A non-experimental, comparative, descriptive cohort study design was used. Following ethical approval, participants who had given their informed written consent had their skin assessed over the areas that were weight-bearing during surgery, using VSA and the SEM measurement. Visual PUs were graded according to the European Pressure Ulcer Advisory Panel and National Pressure Ulcer Advisory Panel ulcer grading system. Assessments took place preoperatively, then daily on the ward, beginning on day one postoperatively and continuing for three days or until discharge.

RESULTS

Of the 231 participants, who had a mean age of 57.50 years, 55.8% (n=129) were male. The most common comorbidity was cardiology/vascular (n=42; 18.2%). Just over half (52.4%; n=121) underwent orthopaedic surgery and 47.6% (n=110) underwent non-orthopaedic surgery; 70% (n=163) received a general anaesthetic and 43% (n=100) were in the supine decubitus position during surgery. PU incidence was 51% (n=116), according to SEM measurement, and 3% (n=7) according to VSA. Among the seven participants who developed a visual PU, 10 PUs at stage 1 developed (31%); some patients developed more than one PU. Of the participants who had assessments for three days postoperatively, 94% (n=61) had a persistently high SEM delta on day three. The variables that emerged as statistically significantly related to abnormal SEM measurement deltas among these participants were: surgery duration (p=0.038); having orthopaedic surgery (p=0.020); supine surgical position (p=0.003); spinal anaesthetic type (p=0.0001); and Waterlow and Braden mobility subscale day one postoperatively (p=0.0001). None of the variables had a statistically significant influence on abnormal VSA.

CONCLUSION

Surgical patients, because of immobility, are vulnerable to the action of compression and shear forces. These forces cause changes at a cellular level that trigger inflammation, which is a precursor to early tissue damage. SEM measurement can detect this tissue damage from the increase in the underlying tissue water content that results from inflammation. From the findings of this study, SEM measurement is very promising in the detection of early tissue damage in those at risk of PU development among the surgical population.

Developing Algorithm Based on Activity and Mobility for Pressure Ulcer Risk Among Older Adult Residents: Implications for Evidence-Based Practice

BACKGROUND

A pressure ulcer (PU) is a localized injury to the skin or underlying tissue usually over a bony prominence. The prevention PU per patient per day is costly; therefore, the detection of a PU at its earliest stage is imperative to afford timely interventions. Currently, there are very few clinically useful tools to assist with early PU detection and prevention.

AIM

There were two primary aims of this study: (1) to investigate the relationship between activity, mobility, and PU development; and (2) to ascertain the next steps for delineating an algorithm based on activity and mobility for detecting PU risk among older adult residents in long-term care.

METHOD

This quantitative, prospective, descriptive, non-experimental study was conducted between July 2019 and March 2020 among 53 older adult residents who were followed for 4 consecutive days. Participants' Braden score, Elderly Mobility Scale (EMS) score, Movement Level, and 6-item Cognitive Impairment Test score were assessed. Further, the sacrum and heels were assessed daily using a non-invasive subepidermal moisture (SEM) scanner and visual skin assessment (VSA). SEM values > 0.5 were considered as indicative of the presence of an SEM-PU.

RESULTS

The incidence rate of VSA-PU was 15.1% (N = 8). There was an incidence of 87.5% (N = 42) of SEM-PU damage. According to the Braden subscale, Mobility Braden, most of the participants (62.2%, N = 33) were assessed as having no limitations/slightly limited mobility, while the EMS indicated that most of the participants (67.9%, N = 36) were classed in an independent category. From the 42 SEM-PUs observed, 62% (N = 26) occurred among the low movers, and 38% (N = 16) occurred among the high movers.

LINKING EVIDENCE TO ACTION

Using traditional methods for the assessment of movement does not provide insight into the protective nature of the movement. Given that both low- and high-moving patients can develop tissue damage, it is important to focus on the assessment of movement using more objective measures and algorithms, which enable real-time assessment of the protective nature of the movement. This would enable development of person-centered PU prevention strategies to reduce the burden of this significant healthcare problem.

Clinical profile of the SEM Scanner - Modernizing pressure injury care pathways using Sub-Epidermal Moisture (SEM) scanning

INTRODUCTION

Pressure injuries (PIs) are a global health concern. Current PI care standards, including skin tissue assessments (STA) and health care professional (HCP) clinical judgment, diagnose visibly manifested PIs on the skin's surface, i.e. after the damage has already occurred. However, objective assessment of early-stage, non-visible, pressure-induced tissue damage is clinically impossible within the current standard of care. The SEM Scanner is the first device authorized by the Food and Drug Administration (FDA) that addresses this unmet clinical need.

AREAS COVERED

This review describes the novel sub-epidermal moisture (SEM) scanning technology of the device and summarizes the clinical safety and efficacy data that support the use of the scanner in routine PI care practice.

EXPERT OPINION

The clinical strategy for developing the SEM Scanner is noteworthy. SEM technology using anatomy-specific data enables HCPs to provide early PI prevention interventions before visible signs of tissue damage develop while the damage is still reversible. When adopted into routine practice, the device identifies an increased risk of developing PIs 5 days (median) earlier than STA. FDA clearance was based on bench studies and data from three foundational trials that demonstrate the diagnostic accuracy of the device algorithm significantly exceeding clinical judgment (p < 0.001).

Natural History of Pressure Injury Among Ethnically/Racially Diverse Nursing Home Residents: The Pressure Ulcer Detection Study

The current observational study provides descriptive data on 270 pressure injuries (PrIs) among 142 racially/ethnically diverse nursing home (NH) residents over 16 weeks. Weekly assessments were conducted with the Bates-Jensen Wound Assessment Tool. NH data were obtained from public government websites. NH, resident, and PrI characteristics across race/ethnicity groups were compared using analysis of variance and chi-square. Participants were 62% female and 89% functionally dependent. More Black and Asian individuals had peripheral vascular disease. More Black individuals had persistent trunk and Stage 4 PrIs. Black and Hispanic individuals had normal skin color surrounding PrIs. More Asian individuals had PrIs surrounded by purple/red discolored skin. More Black individuals' heel PrIs were unstageable, necrotic, and showed no granulation. Black and Hispanic individuals exhibited more deep tissue injury. No NH or prevention differences existed. Health disparities found validate administrative data results. Differences in PrI characteristics should be further examined among diverse NH residents. [Journal of Gerontological Nursing, 47(3), 37-46.].

Our contemporary understanding of the aetiology of pressure ulcers/pressure injuries

In 2019, the third and updated edition of the Clinical Practice Guideline (CPG) on Prevention and Treatment of Pressure Ulcers/Injuries has been published. In addition to this most up‐to‐date evidence‐based guidance for clinicians, related topics such as pressure ulcers (PUs)/pressure injuries (PIs) aetiology, classification, and future research needs were considered by the teams of experts. To elaborate on these topics, this is the third paper of a series of the CPG articles, which summarises the latest understanding of the aetiology of PUs/PIs with a special focus on the effects of soft tissue deformation. Sustained deformations of soft tissues cause initial cell death and tissue damage that ultimately may result in the formation of PUs/PIs. High tissue deformations result in cell damage on a microscopic level within just a few minutes, although it may take hours of sustained loading for the damage to become clinically visible. Superficial skin damage seems to be primarily caused by excessive shear strain/stress exposures, deeper PUs/PIs predominantly result from high pressures in combination with shear at the surface over bony prominences, or under stiff medical devices. Therefore, primary PU/PI prevention should aim for minimising deformations by either reducing the peak strain/stress values in tissues or decreasing the exposure time.

Subepidermal Moisture and Pressure Injury in a Pediatric Population: A Prospective Observational Study

PURPOSE

To describe relationships between subepidermal moisture (SEM) and visual skin assessment of pressure injury (PI) in children.

DESIGN

Prospective descriptive study.

SUBJECTS AND SETTING

Twenty-four participants aged 8 to 16 years recruited from a pediatric orthopedic unit in a children's hospital in Ireland.

METHODS

Subepidermal moisture measured with the SEM scanner (Bruin Biometrics, Los Angeles, California) ranged from 0 to 7 picoFarads [pF], and visual observation of trunk and heels occurred daily for 3 days after admission to the unit and/or after surgery. Skin was assessed for discoloration categorized as blanchable erythema, stage 1 PI, or deep tissue injury (DTI). Any open wound PI was classified as stage 2, 3, 4, or unstageable. Demographic, medical, and pain data were collected. Chi-square test, t tests, analysis of variance, and regression were used to describe data and examine relationships.

RESULTS

Participants were pediatric patients; 100% (n = 24) were white, 62% (n = 15) were female, 8 to 16 years of age (mean = 12.5 ± 2.5 years), and 29% (n = 7) had fractures and 71% (n = 17) surgery diagnoses. Blanchable erythema incidence was 21% (n = 5) and stage 1 PI incidence was 42% (n = 10); nearly all at heels. Deep tissue injury incidence was 4% (one sacral DTI). Stage 2 or greater PI incidence was 4% (one heel stage 2 PI). For skin that was assessed as normal in this pediatric population, SEM for trunk was 2.65 to 2.76 pF and for heels 2.37 to 2.41 pF. Subepidermal moisture for blanchable erythema and stage 1 PI was higher (range, 3.2-3.7 pF) and significant at trochanters and heels (left trochanter: P = .003; right trochanter: P = .02; right and left heels: P = .000). Nominal regression, controlling for participant and assessment day, showed SEM a predictor of erythema and stage 1 PI at heels. We also found that SEM was higher with pain (significant at sacrum and heels).

CONCLUSIONS

In this pediatric population, SEM values over skin assessed as normal are lower than SEM values reported for normal skin in adults, 2.37 to 2.76 pF. Subepidermal moisture was significantly higher for blanchable erythema and stage 1 PI at trochanters and heels, and with the presence of pain at sacrum and heels. We recommend that SEM should be examined for detecting PIs in pediatric populations; SEM and pain should be explored in larger pediatric and adult populations.

Evaluating the sensitivity, specificity and clinical utility of algorithms of spatial variation in sub-epidermal moisture (SEM) for the diagnosis of deep and early-stage pressure-induced tissue damage

BACKGROUND

Sub-epidermal moisture (SEM) is a measurable biomarker detecting early pressure damage in order to objectively support current 'gold standard' skin tissue assessments (STA) for the detection of deep and early-stage pressure-induced injuries or ulcers (PI/PUs).

OBJECTIVE

A multi-site, dual arm, cross sectional, retrospective study was conducted to evaluate the sensitivity, specificity and clinical utility of spatial variation in SEM readings between healthy and damaged skin tissue.

METHOD

The study enrolled 175 subjects: 125 with confirmed PI/PUs or suspected deep tissue injury (sDTI), and 50 confirmed healthy subjects. Expert principal investigators and PI/PU healthcare practitioners (HCPs) evaluating all subjects were trained in SEM measurements but blinded to clinical interpretation of SEM readings. Sequential and spatial SEM readings of the sacrum and heels, subjects' demographic data, STAs, risk assessment tool scores (RATS), pain assessment and potential confounders were recorded. Independent statistical analyses were performed.

RESULTS

Mean spatial SEM measures within subjects with healthy tissue and within subjects with damaged tissue were statistically similar. Mean spatial SEM measures within anatomies of subjects with damaged tissue were significantly different (p<0.05). There was no significant difference between spatial readings in healthy subjects. Algorithms computing a range of SEM delta thresholds indicated a sensitivity of 82-87% and a specificity of 51-88% at an SEM delta ≥0.6. Receiver operating characteristic (ROC) curves computed areas under the curve (AUC) of 0.7809-0.9181 (95% CI: 0.7221-0.8817, 0.8397-0.9545, p<0.0001) exceeding clinical judgement.

CONCLUSION

These SEM data augment clinical decision-making for developing intact skin PI/PUs including sDTIs and Stage I PI/PUs. Informing HCPs of this subclinical, non-visible skin and tissue damage and providing opportunities for alternative PI/PU care pathways is an exciting prospect.

Clinical impact of a sub-epidermal moisture scanner: what is the real-world use?

OBJECTIVE

The presence of sub-epidermal moisture (SEM) over a bony prominence is indicative of incipient pressure ulcer (pressure injury/decubitus/bedsore) (PU). Early identification of patients at increased risk of PU can prompt interventions that reduce the incidence and severity of hospital (or community)-acquired PUs (HAPUs). This study evaluated the clinical utility of a SEM Scanner device in HAPU management.

METHOD

The study used a pragmatic 'real-world' approach. HAPU data before and during SEM Scanner use were obtained through routine audit. Patients had regular visual and daily SEM Scanner skin assessments over the sacrum and heels. Nursing care otherwise followed standard of care according to the established protocols of individual participating sites. HAPU incidence rates were determined and feedback gathered from health professionals on how the device influenced HAPU-related clinical decision-making.

RESULTS

There were 15 participating sites: 13 acute care, one palliative care and one community care setting. The sample size was 1478 patients. All sites reported a substantial reduction in mean HAPU incidence: 87.2% in acute care settings; 46.7% in the palliative care setting and 26.7% in the community care setting. A 100% incidence reduction was reported in 10 (66.7%) sites. In the palliative care setting, SEM Scanner results changed HAPU-related clinical decision-making for 40% of patients scanned. The community care site demonstrated a 82% change in clinical decision-making.

CONCLUSION

In this study, SEM analysis fitted seamlessly into routine skin assessment and enabled early identification of increased risk of tissue damage, with clinically important reductions in the incidence of HAPU across all participating sites.

Anatomical variability of sub-epidermal moisture and its clinical implications

BACKGROUND

Technologies have been developed to monitor changes in dermal oedema, indicative of the early signs of pressure ulcers. However, there is limited information on the effects of regional differences in tissue morphology on these sub-epidermal moisture (SEM) parameters. This study was designed to investigate the absolute SEM readings across different anatomical sites using a commercial device.

METHODS

Twenty-four healthy participants were recruited to evaluate basal SEM values at different bony prominences, sampled by an experienced operator.

RESULTS

Distinct differences were observed in unloaded SEM values across different anatomical sites, notably between the upper and lower extremities. A high degree of variability was observed in particular sites, such as the heels. Moreover, SEM values at certain locations revealed significant relationships with age, BMI and gender (p < 0.05).

CONCLUSION

The study revealed a high level of variability between and within anatomical sites in a healthy cohort of participants. Determining the changes in local skin and sub-dermal tissue status using SEM may require consideration of both site specific and individual demographic factors, with further research needed in cohorts at risk of pressure ulcers.

Community-Acquired Pressure Injuries in the Acute Care Setting

OBJECTIVE

To explore the population of patients with a community-acquired pressure injury (CAPI) admitted to an acute care facility from December 2018 to December 2019. The specific aims of the study were to identify the (1) number of patients admitted with a CAPI, (2) type and frequency of pressure injury (PI), (3) location of residence prior to admission, (4) general demographics of the patient, and (5) condition of the PI at discharge.

METHODS

In this retrospective descriptive study, participants were identified and pulled from the hospital database at a 260-bed level 2 trauma center. Patients' charts were identified by searching for nursing documentation of CAPIs. The exclusion criterion was charts that did not include verification of PI by a certified wound nurse. Data were pulled from the electronic medical record, verified by the certified wound nurse, and reviewed for participant demographics and implementation of PI prevention and treatment.

RESULTS

Over the course of the year, 88 patients had a CAPI. The majority lived at home (86.4%), were male (68.2%), and had stage 2 PIs (37%) on the sacrum (30.7%) or coccyx (51.1%). All participants had multiple comorbidities. Few PIs were from postacute care settings (11%) or another acute care hospital (1.1%). On average, patients had more than one PI. All patients had decreased or impaired mobility and mean body mass index of 26.38 ± 7.23 kg/m2. No one developed a new PI while in the acute care setting, and many of the CAPIs either healed (69.3%) or stabilized (22.7%).

CONCLUSIONS

Providers have an opportunity to make a difference in the prevalence of PIs occurring outside of acute and postacute care settings.

Pressure Injury Prevention Considerations for Older Adults

There are well-documented physiologic changes that occur in the human body during the aging process, such as decreased body fat, decreased muscle mass, cellular senescence, changes in skin pH, decreased metabolism, decreased immune function, vascular changes, altered tissue perfusion, nutritional status changes, and poor hydration. These changes affect skin integrity and wound healing, and raise the risk of pressure-related skin injury. This article discusses aging as a risk factor for pressure injury (PrI). Topics include evidence for advancing age as a significant PrI risk factor, identifying pathophysiologic changes/mechanisms of aging, and specific PrI preventive interventions to consider in older adults.

The subepidermal moisture scanner: the technology explained

The objective of this article is to explain the biophysical principles underlying the design of the subepidermal moisture (SEM) scanner, commercially known as the 'SEM scanner'. We also describe the mode of operation of the SEM scanner in monitoring tissue health and detecting subtle abnormal changes in tissue physiology in patients and anatomical sites at a risk of a pressure ulcer (PU: also known as a pressure injury). The technology of the SEM scanner was approved last year for sales in the US by the Food and Drug Administration (FDA). The SEM scanner detects changes in fluid contents of human skin and subdermal tissues, to a tissue depth of several millimetres, by measuring 'capacitance', an electrical property of the locally examined tissue site to store electric charge. The capacitance of tissues, called 'biocapacitance', is strongly affected by the amount of fluid (water) in the tissue. When the first cells die in a forming PU, inflammatory signalling causes the permeability of blood vessel walls to increase and oedema to develop. Simply, the scanner detects the early appearance of oedema, which is called 'micro-oedema.' Calculation of a 'SEM-delta' value, which compares biocapacitance measurements, acquired across several tissue sites, some of which are healthy and others where the PU may evolve, eliminates potential effects of systemic changes in tissue fluid contents and provides a consistent quantitative measure of the tissue health conditions at the monitored anatomical site. Here, we describe SEM scanner technology, how it operates and has been laboratory tested (in computer simulations, in silico) before commercial launch. We explain why targeting the physical biomarker of oedema leads to the documented success of the SEM scanner in the multiple published clinical trials, proving its ability to early detect PUs that form under intact skin.

Risk factors for developing heel ulcers for bedridden patients: A finite element study

BACKGROUND

The heel is one of the most common sites of pressure ulcers and the anatomical location with the highest prevalence of deep tissue injury. Several finite element modeling studies investigate heel ulcers for bedridden patients. In the current study we have added the implementation of the calf structure to the current heel models. We tested the effect of foot posture, mattress stiffness, and a lateral calcaneus displacement to the contact pressure and internal maximum shear strain occurring at the heel.

METHODS

A new 3D finite element model is created which includes the heel and calf structure. Sensitivity analyses are performed for the foot orientation relative to the mattress, the Young's modulus of the mattress, and a lateral displacement of the calcaneus relative to the other soft tissues in the heel.

FINDINGS

The models predict that a stiffer mattress results in higher contact pressures and internal maximum shear strains at the heel as well as the calf. An abducted foot posture reduces the internal strains in the heel and a lateral calcaneus displacement increases the internal maximum shear strains. A parameter study with different mattress-skin friction coefficients showed that a coefficient below 0.4 decreases the maximum internal shear strains in all of the used loading conditions.

INTERPRETATION

In clinical practice, it is advised to avoid internal shearing of the calcaneus of patients, and it could be taken into consideration by medical experts and nurses that a more abducted foot position may reduce the strains in the heel.

Sub-epidermal moisture measurement: an evidence-based approach to the assessment for early evidence of pressure ulcer presence

This paper aims to discuss the literature pertaining to early pressure-shear induced tissue damage detection, with emphasis on sub-epidermal moisture measurement (SEM). The current method for pressure detection is visual skin assessment (VSA); however, this method is fraught with challenges. Advances in early detection of pressure ulcers are reported in the literature and mainly involve measuring inflammation markers on weight-bearing anatomical areas in order to capture the first signs of tissue damage. One novel technique currently in use is SEM measurement. This biophysical marker is the product of plasma that leaks as a response to local inflammation arising due to pressure-shear induced damage over bony prominences. The early detection of tissue damage is beneficial in two different ways. First, it enables early intervention when the damage is still microscopic and reversible and, therefore, has the potential to prevent further aggravation of healthy surrounding tissue. This arises by avoiding the causation of the problem and stopping the knock-on effect of inflammation, especially when the rapid pressure ulceration pathway of deformation is in place. Second, when the slow ischaemic-reperfusion related mechanism is undergoing, cell death can be avoided when the problem is identified before the cell reaches the "death threshold," completely averting a pressure ulcer.

The subepidermal moisture scanner: the technology explained

The objective of this article is to explain the biophysical principles underlying the design of the subepidermal moisture (SEM) scanner, commercially known as the ‘SEM scanner’. We also describe the mode of operation of the SEM scanner in monitoring tissue health and detecting subtle abnormal changes in tissue physiology in patients and anatomical sites at a risk of a pressure ulcer (PU: also known as a pressure injury). The technology of the SEM scanner was approved last year for sales in the US by the Food and Drug Administration (FDA). The SEM scanner detects changes in fluid contents of human skin and subdermal tissues, to a tissue depth of several millimetres, by measuring ‘capacitance’, an electrical property of the locally examined tissue site to store electric charge. The capacitance of tissues, called ‘biocapacitance’, is strongly affected by the amount of fluid (water) in the tissue. When the first cells die in a forming PU, inflammatory signalling causes the permeability of blood vessel walls to increase and oedema to develop. Simply, the scanner detects the early appearance of oedema, which is called ‘micro-oedema.’ Calculation of a ‘SEM-delta’ value, which compares biocapacitance measurements, acquired across several tissue sites, some of which are healthy and others where the PU may evolve, eliminates potential effects of systemic changes in tissue fluid contents and provides a consistent quantitative measure of the tissue health conditions at the monitored anatomical site. Here, we describe SEM scanner technology, how it operates and has been laboratory tested (in computer simulations, in silico) before commercial launch. We explain why targeting the physical biomarker of oedema leads to the documented success of the SEM scanner in the multiple published clinical trials, proving its ability to early detect PUs that form under intact skin.

A blinded clinical study using a subepidermal moisture biocapacitance measurement device for early detection of pressure injuries

This study aimed to evaluate the sensitivity and specificity of subepidermal moisture (SEM), a biomarker employed for early detection of pressure injuries (PI), compared to the "Gold Standard" of clinical skin and tissue assessment (STA), and to characterize the timing of SEM changes relative to the diagnosis of a PI. This blinded, longitudinal, prospective clinical study enrolled 189 patients (n = 182 in intent-to-treat [ITT]) at acute and post-acute sites (9 USA, 3 UK). Data were collected from patients' heels and sacrums using a biocapacitance measurement device beginning at admission and continuing for a minimum of 6 days to: (a) the patient developing a PI, (b) discharge from care, or (c) a maximum of 21 days. Standard of care clinical interventions prevailed, uninterrupted. Principal investigators oversaw the study at each site. Blinded Generalists gathered SEM data, and blinded Specialists diagnosed the presence or absence of PIs. Of the ITT population, 26.4% developed a PI during the study; 66.7% classified as Stage 1 injuries, 23% deep tissue injuries, the remaining being Stage 2 or Unstageable. Sensitivity was 87.5% (95% CI: 74.8%-95.3%) and specificity was 32.9% (95% CI: 28.3%-37.8%). Area under the receiver operating characteristic curve (AUC) was 0.6713 (95% CI 0.5969-0.7457, P < .001). SEM changes were observed 4.7 (± 2.4 days) earlier than diagnosis of a PI via STA alone. Latency between the SEM biomarker and later onset of a PI, in combination with standard of care interventions administered to at-risk patients, may have confounded specificity. Aggregate SEM sensitivity and specificity and 67.13% AUC exceeded that of clinical judgment alone. While acknowledging specificity limitations, these data suggest that SEM biocapacitance measures can complement STAs, facilitate earlier identification of the risk of specific anatomies developing PIs, and inform earlier anatomy-specific intervention decisions than STAs alone. Future work should include cost-consequence analyses of SEM informed interventions.

Prediction of Diabetic Foot Ulceration: The Value of Using Microclimate Sensor Arrays

BACKGROUND

Accurately predicting the risk of diabetic foot ulceration (DFU) could dramatically reduce the enormous burden of chronic wound management and amputation. Yet, the current prognostic models are unable to precisely predict DFU events. Typically, efforts have focused on individual factors like temperature, pressure, or shear rather than the overall foot microclimate.

METHODS

A systematic review was conducted by searching PubMed reports with no restrictions on start date covering the literature published until February 20, 2019 using relevant keywords, including temperature, pressure, shear, and relative humidity. We review the use of these variables as predictors of DFU, highlighting gaps in our current understanding and suggesting which specific features should be combined to develop a real-time microclimate prognostic model.

RESULTS

The current prognostic models rely either solely on contralateral temperature, pressure, or shear measurement; these parameters, however, rarely reach 50% specificity in relation to DFU. There is also considerable variation in methodological investigation, anatomical sensor configuration, and resting time prior to temperature measurements (5-20 minutes). Few studies have considered relative humidity and mean skin resistance.

CONCLUSION

Very limited evidence supports the use of single clinical parameters in predicting the risk of DFU. We suggest that the microclimate as a whole should be considered to predict DFU more effectively and suggest nine specific features which appear to be implicated for further investigation. Technology supports real-time in-shoe data collection and wireless transmission, providing a potentially rich source of data to better predict the risk of DFU.

Correlation of bioimpedance changes after compressive loading of murine tissues in vivo

OBJECTIVE

Rises in the incidence of pressure ulcers are increasingly prevalent in an aging population. Pressure ulcers are painful, are associated with increased morbidity and mortality, increase the risk for secondary infections and inpatient stay, and adds $26.8 billion annually to the healthcare costs of the USA. Evidence suggests that a change in the bioimpedance of living tissue in response to continuous local contact pressure can be a useful indicator for the onset of pressure injuries.

APPROACH

Thirty-five Sprague Dawley rats were subjected to various skin pressures for differing periods of time via a surgically inserted steel disk and an externally applied magnet. Contact pressure and bioimpedance were measured and correlated with tissue loading intensity and compared to clinical ulcer grading.

MAIN RESULTS

Moderate relationships between bioimpedance changes and tissue loading intensity were found. Stronger correlations were found by utilizing a combination of bioimpedance and phase angle. Thresholds were applied to the bioimpedance parameters and the usefulness of bioimpedance in classifying different ulcer stages is demonstrated.

SIGNIFICANCE

These results indicate that bioimpedance may be useful as an early indicator of pressure ulcer formation and has practical significance in the development of early pressure injury detection devices.

Phantom testing of the sensitivity and precision of a sub-epidermal moisture scanner

The majority of pressure ulcers (PUs) including deep tissue injuries (DTIs) are preventable, and even reversible if detected in their early phase. One of the greatest barriers in PU prevention is that clinicians traditionally depended on subjective and qualitative techniques, particularly routine visual skin assessments that would only document existing, macroscopic PUs/DTIs, rather than preventing them or detecting them at their microscopic phase. At the early phase of cell damage, when a forming PU is still microscopic, there is a local increase in extracellular fluid contents within affected tissues, which is called sub-epidermal moisture (SEM). This new understanding has led to an emerging technology, a SEM Scanner (BBI LLC, Bruin Biometrics) that has been designed to effectively examine the health status of tissues, by measuring local changes in the biophysical SEM marker. In the present work, the SEM Scanner was tested under controlled laboratory conditions to experimentally determine its sensitivity and precision in identifying small (1 mL) water content changes in phantoms of the human heel and skull/face, which simulated common PU development scenarios. In both phantom configurations, the locally increased water contents resulted in consistent, statistically significant elevated SEM readings, which confirms that the SEM Scanner is able to detect fluid content changes that are as small as 1 mL. In agreement with a simplified theoretical (mathematical) SEM model, which was also developed here, changes in water contents had a consistent trend of effect on SEM delta values, which increased with each 1 mL increment in intra-tissue-substitute water contents.

Reliability of the Bates-Jensen wound assessment tool for pressure injury assessment: The pressure ulcer detection study

The Bates-Jensen Wound Assessment Tool (BWAT) is used to assess wound healing in clinical practice. The purpose of this study was to evaluate BWAT use among nursing home residents with pressure injury. Findings and reliability estimates from the BWAT related to pressure injury characteristics (stage, anatomic location) and natural history (resolved, persisted) among 142 ethnically and racially diverse residents are reported. In this prospective 16-week study, 305 pressure injuries among 142 participants (34% prevalence) are described by stage, anatomic location, and BWAT scores. Visual and subepidermal moisture assessments were obtained from sacrum, buttock, ischial, and heel ulcers weekly. Participants were 14% Asian, 28% Black, 18% Hispanic, 40% White with a mean age of 78 ± 14 years, and were 62% female; 80% functionally dependent (bed mobility extensive/total assistance) and at risk (Braden Scale score 14 ± 2.7). The reliability coefficient for BWAT score (all participants, all anatomic locations) was high (r = 0.90; p < 0.0001; n = 1,161 observations). Weighted Kappas for characteristics ranging from 0.46 (skin color surrounding wound) to 0.79 (undermining) were consistent for all participants. BWAT scores showed strongest agreement coefficients for stage 4 pressure injury (r = 0.69), pressure injuries among Asian and White ethnicity/racial groups (r = 0.89, and r = 0.91, respectively), and sacrum anatomic location (r = 0.92) indicating scores are better correlated to fair skin tones. Lower agreement coefficients were demonstrated for stage 2 pressure injury (r = 0.38) and pressure injuries among African American and Hispanic ethnicity/racial groups (r = 0.88 and 0.87, respectively). BWAT scores were significantly different by pressure injury stage (F = 496.7, df = 6, p < 0.001) and anatomic location (F = 33.76, df = 8, p < 0.001). BWAT score correlated with pressure injury natural history (ulcer resolved 18.4 ± 7.4, ulcer persisted 24.9 ± 10.0; F = 70.11, df = 2, p < 0.001), but not with comorbidities. The BWAT provides reliable, objective data for assessing pressure injury healing progress.

The prevalence of pressure ulcers in community-dwelling older adults: A study in an Indonesian city

The objectives of this study were to investigate the prevalence and the characteristics of pressure ulcers (PU) in community‐dwelling older adults in Indonesia, including specific characteristics of the PU patients and their use of formal and informal care. A cross‐sectional design was used for the study, with 325 participants aged 60 years or older, randomly chosen from the general community. The overall PU prevalence and the PU prevalence excluding category 1 were 10.8% (95% confidence interval [CI], 5.8‐15.8) and 5.2% (95% CI 0.2‐10.2), respectively. Category 1 PUs were mostly (34.3%) located on knees and toes, while category 2 and higher PUs were mostly (70.4%) located on the shoulder, sacrum, and hip. The main factors that contributed strongly to PUs among older adults in the community were the degree of physical activity, problems with sensory perception, and having a history of stroke. None of the participants with a PU received wound care or information about PUs from formal caregivers and only 11.4% received wound care from family caregivers. This study shows that pressure ulcers in community‐dwelling older adults in Indonesia are a relevant and largely unaddressed problem. Developing an intervention program to manage the PU problem in the community is recommended.

Minimum Detectable Changes Associated with Tissue Dielectric Constant Measurements as Applicable to Assessing Lymphedema Status

Background: Tissue dielectric constant (TDC) measurements are increasingly being used as a tool to help characterize lymphedema features, detect its presence, and assess treatment related changes. Although the underlying physics of this technology has been well described in the literature, there has been little systematic study of in vivo reliability aspects. A central unanswered question is the minimal detectable change (MDC) that, with a given level of confidence, may be ascribed to this technology. Our goal was to address this issue using test-retest measurements from which intraclass correlations coefficients (ICC) and MDC could be estimated. Methods and Results: Forty volunteers (20 females) aged 19-61 years with body mass indices of 14.7-47 kg/m² and body fat percentages of 12.0%-48.9% were evaluated. Two measurers (M1 and M2) used two different TDC measuring devices (multiprobe and compact) to measure TDC in triplicate sequentially and bilaterally at three locations; anterior forearm, hand palmar mid-thenar eminence, and dorsum mid-web. These measurements were made by each measurer twice constituting test-retest values (T1 and T2). From these measurements ICC_2,1 and MDC at 95% confidence were determined for each site and probe for absolute TDC values and for inter-side ratios. MDC values for absolute TDC ranged from 2 to 9 TDC units, and for inter-side ratios ranged from 5.3% to 8.0% depending on site and probe. ICC_2,1 values ranged from 0.765 to 0.982. Conclusions: The MDC values herein documented may be used to provide guidance to aid interpretation of measured TDC changes or differences in a clinical environment.

Subepidermal moisture detection of heel pressure injury: The pressure ulcer detection study outcomes

We examined subepidermal moisture (SEM) and visual skin assessment of heel pressure injury (PrI) among 417 nursing home residents in 19 facilities over 16 weeks. Participants were older (mean age 77 years), 58% were female, over half were ethnic minorities (29% African American, 12% Asian American, 21% Hispanic), and at risk for PrI (mean Braden Scale Risk score = 15.6). Blinded concurrent visual assessments and SEM measurements were obtained at heels weekly. Visual skin damage was categorised as normal, erythema, stage 1 PrI, deep tissue injury (DTI) or stage 2 or greater PrI. PrI incidence was 76%. Off-loading occurred with pillows (76% of residents) rather than heel boots (21%) and often for those with DTI (91%). Subepidermal moisture was measured with a device where higher readings indicate greater moisture (range: 0-70 tissue dielectric constant), with normal skin values significantly different from values in the presence of skin damage. Subepidermal moisture was associated with concurrent damage and damage 1 week later in generalised multinomial logistic models adjusting for age, diabetes and function. Subepidermal moisture detected DTI and differentiated those that resolved, remained and deteriorated over 16 weeks. Subepidermal moisture may be an objective method for detecting PrI.