Risk factors for pressure ulcer development in critically Ill patients: A conceptual model to guide research

Explore the effect of pressure and time of compression on the risk of intraoperatively acquired pressure injury based on theoretical framework: A prospective study

Surgery is a high risk factor for the occurrence of pressure injury (PI). On the basis of theoretical research, pressure and duration of pressure are key factors affecting PI. Pressure is affected by the individual pressure redistribution capacity. So our study aims to explore how the surgery time and pressure intensity affect the occurrence of PI and what are the risk factors. A prospective study. A total of 250 patients who underwent elective surgery in a grade-A general hospital from November 2021 to February 2023 were selected and divided into a group of 77 patients with IAPI (intraoperatively acquired pressure injury) and a group of 173 patients with no IAPI. Visual pressure inductive feedback system and body composition analysis technology were used to record the local pressure value and change of patients before and after anaesthesia. Relevant data of the patients were collected to explore the influencing factors. The maximum pressure and average pressure at the pressure site of the same patient changed before and after anaesthesia, and the pressure after anaesthesia was significantly higher than that before anaesthesia. There was no statistical difference in the average pressure after anaesthesia (p > 0.05), but the maximum pressure in the IAPI group was higher than that in the non-occurrence group (p < 0.05). The average pressure multiplied by the operation time in IAPI group is significantly higher than that in the non-IAPI group (p < 0.01). Multiple linear regression analysis (stepwise regression) showed that fat-free weight, age, waist circumference, body mass index (BMI) and gender were taken as independent variables into the regression model, affecting the maximum pressure. In addition, operation time ≥4 h may be a high risk factor for IAPI. In future studies, more objective research tools can be applied to improve the accuracy of predicting the risk of IAPI. In addition to gender and BMI, follow-up studies may consider including measures such as waist circumference and fat-free body weight in IAPI risk assessment to guide the clinical nursing work more scientifically.

Validity and Reliability Evidence of the Munro Scale for Perioperative Patients, Part I: Correlation, Multiple Regression, and Reliability

Background and Purpose: Patients undergoing surgery are at risk of pressure injury development and should be assessed to ensure measures are taken for prevention. The study's purpose was to examine the causal relationships and reliability of the Munro Pressure Injury Risk Assessment Scale for Perioperative Patients (Munro Scale). The Munro Scale is the first dynamic risk scale available for this patient population in the acute clinical setting. Methods: This study was a retrospective review to explore the relationships of the variables in the Munro Scale, identify the strongest predictors, and measure the reliability of previously collected data from two northeastern community hospitals. A total of 630 risk assessments were analyzed to obtain regression, correlation, and reliability evidence for the Munro Scale. Results: The correlation analysis among the 15 risk variables and combined comorbidities revealed commonalities among the variables and significant relationships to the final postoperative injury score. The model as a whole is significant to predict the final level of risk. Coefficient alpha revealed a lower than anticipated reliability when compared to the Chinese, Turkish, and Brazilian versions of the Munro Scale. Conclusions: There are significant relationships among the variables, and the scale is acceptable for use in the acute perioperative practice setting. This study has both clinical and statistical significance.

Preventing Pressure Injuries in Nursing Home Residents Using a Low-Profile Alternating Pressure Overlay: A Point-of-Care Trial

BACKGROUND

Pressure injuries (PIs) are a significant concern for patients with very limited mobility in skilled nursing facilities. Conflicting clinical guidelines and a lack of effectiveness data for the various support surfaces reduces the efficacy of PI prevention programs.

OBJECTIVE

To assess the preventive effectiveness (incidence of facility-acquired PIs) of a low-profile alternating pressure (AP) support surface plus facility-specific PI prevention programs in patients at high risk for PI.

DESIGN AND SETTING

Prospective, multicenter, point-of-care observational study in two for-profit nursing homes in the northeastern US.

PATIENTS AND INTERVENTION

A retrospective review of 101 residents was performed to determine baseline PI incidence. Then, a consecutive sample of 25 participants was selected based on the following eligibility criteria: high risk for PI, bedbound (20 hours or more per day), and stay in a mechanical ventilation unit for more than 5 days. The participants were placed on an AP overlay positioned above a facility-provided nonpowered reactive support surface.

MAIN OUTCOME MEASURE

The development of any new PI (stage 1-4), deep-tissue injury, or unstageable PI in participants using the AP overlay. The PI incidence for the AP group was compared with the retrospective baseline PI incidence from the same units in the two nursing homes.

MAIN RESULTS

The group using the AP overlay had a significantly lower PI incidence (0/25, 0%) compared with baseline (22/101, 21.8%; P < .001). Almost 80% of the study participants in the AP group were completely immobile, 100% of the participants were bowel- and bladder-incontinent, their average time on the AP overlay was 140.9 ± 94.1 days, and average length of stay in the facility was 633.9 ± 1,129.1 days.

CONCLUSIONS

The low-profile AP overlay was significantly more effective than facility-specific prevention programs alone in preventing PIs in a high-risk nursing home population over an extended period.

Predictors of pressure injury development in critically ill adults: A retrospective cohort study

OBJECTIVE

The purpose of this research was to identify predictors of pressure injury, using data from the electronic health records of critically ill adults.

METHODOLOGY

A retrospective cohort study was conducted using logistic regression models to examine risk factors adjusted for age, gender, race/ethnicity and length of stay.

SETTING

The study cohort included 1587 adults in intensive care units within an urban academic medical centre.

MAIN OUTCOME MEASURES

The presence or absence of a hospital-acquired pressure injury was determined during monthly skin integrity prevalence surveys. All pressure injuries were independently confirmed by two Certified Wound Care Nurses.

RESULTS

Eighty-one (5.1%) of the 1587 cohort patients developed pressure injuries. After adjusting for confounders, the clinical variables associated with pressure injury development included mean arterial pressure <60 mmHg and lowest Total Braden score up to two weeks prior to the date of HAPI development or date of prevalence survey for the comparison group.

CONCLUSIONS

This study provides a more comprehensive understanding about pressure injury risk in critically ill adults, identifying extrinsic and intrinsic factors associated with pressure injury development. Prospective multisite studies are needed to further examine these potential contributors to pressure injury development within the context of adherence to prevention interventions.

The pressure injury predictive model: A framework for hospital-acquired pressure injuries

BACKGROUND

Despite decades of research, pressure injuries continue to be a source of significant pain and delayed recovery for patients and substantial quality and cost issues for hospitals. Consideration of the current thinking around pressure injury risk must be evaluated to improve risk assessments and subsequent nursing interventions aimed at reducing hospital-acquired pressure injuries.

DESIGN

This is a discursive paper using Walker and Avant's (2005) theory synthesis framework to examine the relevance of existing pressure injury models as they align with the current literature.

METHODS

PubMed and CINAHL indexes were searched, first for conceptual models and then for pressure injury research conducted on hospitalised patients for the years 2006-2016. A synthesis of the searches culminated into a new pressure injury risk model.

CONCLUSIONS

Gaps in previous models include lack of attention to the environment, contributing episode-of-care factors and the dynamic nature of injury risk for patients. Through theory synthesis, the need for a new model representing the full risk for pressure injury was identified. The Pressure Injury Predictive Model is a representation of the complex and dynamic nature of pressure injury risk that builds on previous models and addresses new patient, contextual and episode-of-care process influences. The Pressure Injury Predictive Model (PIPM) provides a more accurate picture of the complexity of contextual and process factors associated with pressure injury development.

RELEVANCE TO CLINICAL PRACTICE

Using the PIPM to determine risk can result in improved risk identification. This information can be used to implement targeted, evidence-based pressure injury prevention interventions specific to the patient risk profile, thus limiting unwarranted and unnecessary care.

[Development and Evaluation of Electronic Health Record Data-Driven Predictive Models for Pressure Ulcers]

PURPOSE

The purpose of this study was to develop predictive models for pressure ulcer incidence using electronic health record (EHR) data and to compare their predictive validity performance indicators with that of the Braden Scale used in the study hospital.

METHODS

A retrospective case-control study was conducted in a tertiary teaching hospital in Korea. Data of 202 pressure ulcer patients and 14,705 non-pressure ulcer patients admitted between January 2015 and May 2016 were extracted from the EHRs. Three predictive models for pressure ulcer incidence were developed using logistic regression, Cox proportional hazards regression, and decision tree modeling. The predictive validity performance indicators of the three models were compared with those of the Braden Scale.

RESULTS

The logistic regression model was most efficient with a high area under the receiver operating characteristics curve (AUC) estimate of 0.97, followed by the decision tree model (AUC 0.95), Cox proportional hazards regression model (AUC 0.95), and the Braden Scale (AUC 0.82). Decreased mobility was the most significant factor in the logistic regression and Cox proportional hazards models, and the endotracheal tube was the most important factor in the decision tree model.

CONCLUSION

Predictive validity performance indicators of the Braden Scale were lower than those of the logistic regression, Cox proportional hazards regression, and decision tree models. The models developed in this study can be used to develop a clinical decision support system that automatically assesses risk for pressure ulcers to aid nurses.

Exploring pressures, tissue reperfusion and body positioning: a pilot evaluation

OBJECTIVE

To assess the relationship in healthy adults and critically ill patients between: patient position, body mass index (BMI), patient body temperature, interface pressure (IP) and tissue reperfusion (TR). Also to determine the relationship in critically ill patients between: Sequential Organ Failure Assessment (SOFA) score, Braden Scale score for predicting pressure injury risk, Acute Physiology and Chronic Health Evaluation II (APACHE II) severity of disease classification score, IP and TR.

METHODS

This study took place in a 27-bed intensive care unit (ICU) of an Australian tertiary hospital. IP and TR outcomes were measured at the sacrum and greater trochanter. Repeated measures analyses of variance (ANOVAs) and doubly multivariate repeated measures ANOVAs were conducted using peak pressure index (PPI), peak time (PT), settled time constant (STC) and normalised hyperaemic area (NHA) measures of TR as outcomes. Participant type, body mass index (BMI), Braden and APACHE II scores and patient body temperature were considered as between-groups factors and covariates.

RESULTS

We recruited 23 low- and high-acuity ICU patients and nine healthy adult volunteers. Not all IP readings could be obtained from ICU patients. TR readings were collected from all recruited patients, but not all TR measurements were mutually uncorrelated. Controlling for age, PPI readings differed between participant types (p=0.093), with the highest values associated with high-acuity patients and the lowest with healthy adults; the association was not substantive when controlling for age and BMI. Age was a significant variable (p=0.008), with older participants having higher scores than younger ones. No statistically significant associations between any measured parameter and TR variables were observed. However, temperature was revealed to be related to TR (p=0.091).

CONCLUSIONS

Although not powered to detect significant effects, this pilot analysis has determined several associations of importance, with differences in outcomes observed between low- and high-acuity ICU patients; and between ICU patients and healthy volunteers.

Alteration of Pressure-Induced Vasodilation in Aging and Diabetes, a Neuro-Vascular Damage

Skin is constantly subjected to pressure at different levels. Pressure-induced vasodilation (PIV) is one of the response mechanisms to low pressure that maintains the homeostasis of the skin. PIV results from the interaction of primary afferent nerves and vascular endothelium of skin vessels. Thanks to this cutaneous neuro-vascular interaction, the cutaneous blood flow increase allows the maintenance of an optimal level of oxygenation and minimizes the lack of vascularization of the skin tissue under low pressure. It seems to be associated with the cutaneous protection mechanisms to prevent pressure ulcers. In some contexts, where microangiopathy and neuropathy can occur, such as aging and diabetes, PIV is impaired, leading to a dramatic early decrease in local skin blood flow when low pressure is applied. In aging, PIV alteration is due to endothelial dysfunction, essentially from an alteration of the nitric oxide pathway. In the inflamm-aging context, oxidative stress increases leading to endothelial cell and nerve damages. An age-related sensory neuropathy will exacerbate the alteration of PIV during the aging process. In diabetes, non-controlled hyperglycaemia leads to an increase in several pathological biochemical pathways that involve oxidative stress and can affect PIV. Sorbinil, alagebrium and alpha-lipoic acid are able individually to restore PIV through a possible oxidative stress reduction. Candesartan, an angiotensin II type 1 receptor blocker, is also able to restore PIV and prevent pressure ulcer formation. The possibility of preventing pressure ulcer associated to diabetes and/or aging with the restoration of PIV seems to be a promising research path.

Using Nursing Information and Data Mining to Explore the Factors That Predict Pressure Injuries for Patients at the End of Life

This study investigated the association between patient characteristics and the occurrence of pressure injuries for patients at the end of life. A retrospective study was conducted using data collected from 2062 patients at the end of life between January 2007 and October 2015. In addition to demographic data and pressure injury risk assessment scale scores, injury history, disease type, and length of hospitalization were revealed as the major independent variables for predicting the occurrence of pressure injuries. Both χ tests and t tests were employed for binary variable analysis, and logistic regression was used to conduct multivariate analysis. Classification models were formulated through decision tree analysis, backpropagation neural network, and support vector machine algorithms. The rules obtained using the decision tree algorithm were analyzed and interpreted. The accuracy rate, sensitivity, and specificity of the decision tree, backpropagation neural network, and support vector machine algorithms were 77.15%, 79.54%, and 74.76%; 78.12%, 81.37%, and 74.85%; and 79.32%, 81.03%, and 78.75%, respectively. The predictive factors, ranked in order of importance, were history of pressure injuries, without cancer, excretion, activity/mobility, and skin condition/circulation. These were the primary shared risk factors among the four models used in this study.

Pressure ulcers in cardiac surgery: Few clinical studies, difficult risk assessment, and profound clinical implications

Pressure ulcers (PUs) are a common complication after cardiac surgery, with almost one third of patients suffering from PUs during hospitalisation. Because of the burden that PUs exert on both the patients and the health care system, prevention is of utmost importance. The first step in successful prevention, however, includes the identification of the main features that render patients prone to PU development. Cardiac surgery population is not adequately addressed in current clinical trials and studies. Few studies focused specifically on cardiac surgery patients, but the majority included cardiac surgery patients within a heterogeneous population of acute or critical care patients. Therefore, additional research is warranted to understand the unique risk profile of patients undergoing cardiac surgery. Intraoperative risk factors that affect tissue tolerance have not been thoroughly investigated but are likely to play an important role, which might explain the epidemiology of a PU. Further research is also needed to better comprehend the risk of PUs among cardiac surgery patients and to design effective and tailored preventative measures with the help of newer tools for risk assessment.

Measuring the quality of pressure ulcer prevention: A systematic mapping review of quality indicators

The aim of this study was to provide a systematic overview of available pressure ulcer prevention quality indicators and to evaluate the underlying empirical evidence. A systematic mapping review was conducted with combined searches in Embase and Medline, and websites of relevant institutions and organisations. The eligibility criteria were clear use of the term "quality indicator" regarding pressure ulcer prevention; English or German language; and all settings, populations, and types of resources, including articles, brochures, and online material. In total, n = 146 quality indicators were identified. Most indicators were published in the United States (n = 50). The majority of indicators was developed for the hospital setting (n = 102). Process indicators were the most common (n = 71), followed by outcome indicators (n = 49). Less than half of identified indicators appeared to be practically used. Evidence supporting the validity and reliability were reported for n = 25 and n = 30 indicators respectively. The high number of indicators demonstrate the importance of measuring pressure ulcer prevention quality. This is not an indicator of our ability to accurately measure and evaluate this construct. There is an urgent need to develop evidence-based and internationally comparable indicators to help improve patient care and safety worldwide.

Pressure ulcers in critically ill patients: incidence and associated factors

OBJECTIVE

to identify the incidence and describe the associated factors for pressure ulcers in critically ill patients.

METHOD

this was a prospective cohort study with 77 patients, using a clinical, metabolic assessment and the associated factors for pressure ulcer, applying the risk scales (Braden and Waterlow) and assigning ulcers to categories.

RESULTS

an incidence of 22% (95% CI 12.6 - 31.5), with 17 patients with 32 pressure ulcers in the sacral region (47%), and of Class I (72%). The length of stay was greater than ten days (71%), most admissions were surgical (53%) or for congestive heart failure (24%), and were high risk on the Braden Scale (59%).

CONCLUSION

the study highlights the high incidence of pressure ulcers, clinical and metabolic characteristics and associated factors, as well as the outcome of death, requiring, therefore, preventive measures.

Risk Factors Associated With Pressure Ulcer Formation in Critically Ill Cardiac Surgery Patients: A Systematic Review

BACKGROUND

Cardiac surgery patients are among those most at risk for developing pressure ulcers (PUs), with a reported incidence as high as 29.5%. Although numerous studies documenting PU risk factors and prevention strategies exist, the availability of literature examining risk factors specific to the cardiac surgery population is limited.

AIM

A systematic review was completed that aimed to identify the risk factors associated with PU development in critically ill, adult, cardiac surgery patients.

METHODS

The MEDLINE, CINAHL, and Cochrane databases were searched. Studies that focused on PU risk factors in critical care, surgical intensive care, or cardiac surgery populations and used PU occurrences as an outcome variable were included in the review.

FINDINGS

Twelve high-quality studies were retrieved and included in the review; they revealed 30 potential PU risk factors. Current evidence is limited in 2 important ways. First, the impact of intraoperative factors, such as cardiopulmonary bypass time or body temperature, appears to be underexplored. Second, a substantive discussion of the risk factors associated specifically with deep tissue injuries, a unique PU category, is absent.

CONCLUSION

The relatively high PU incidence among cardiac surgery patients suggests that typical PU prevention methods are insufficient for this population. Targeted prevention measures must be developed and implemented. Completion of this task required identification of risk factors unique to this population. Specific risk factors likely to increase risk among cardiac surgery patients include prolonged exposure to pressure during long surgical procedures, vascular disease, and/or vasopressor use postoperatively. Additional research concerning risk factors specific to this population is urgently needed.

Pressure ulcer dressings in critical patients: a cost analysis

OBJECTIVE

To assess the direct cost of dressings in pressure ulcer treatment.

METHOD

This was a descriptive observational study conducted at an intensive care unit in the Northeast region of Brazil, between November and December 2015. Data were gathered using the Pressure Ulcer Scale for Healing and a form to characterize and assess costs. Values in Brazilian reais (BRL) were converted into U.S. dollars at the exchange rate of USD 0.26/BRL. Univariate and bivariate analyses were conducted.

RESULTS

The sample consisted of 15 patients with at least stage 2 ulcers. There was a significant reduction in costs with dressing materials between the initial and final assessments (p=0.002), with a mean of USD 11.9 (±7.4). The most common topical treatments used were essential fatty acids and papain.

CONCLUSION

Cost reduction was proportional to the stage of pressure ulcer. The role of nurses in creating evidence-based care plans is crucial to improve care management.

OBJETIVO

Avaliar o custo direto com curativos no tratamento de lesões por pressão.

MÉTODO

Estudo observacional descritivo, realizado em Unidade de Terapia Intensiva do nordeste do Brasil, de novembro a dezembro de 2015. Foi aplicada a Pressure Ulcer Scale for Healing e formulário para caracterização e avaliação de custos. Os valores da moeda brasileira (R$) foram convertidos para a moeda norte-americana (US$) à taxa de US$0,26/R$. Foram realizadas análises univariadas e bivariadas.

RESULTADOS

Compuseram a amostra 15 pacientes com lesões, no mínimo, estágio 2. Houve redução significativa dos custos com materiais de curativos entre as avaliações inicial e final (p=0,002), com média de US$11,9 (±7,4). As terapias tópicas mais frequentes foram ácidos graxos essenciais e papaína.

CONCLUSÃO

Verificou-se redução de custos proporcional aos estágios das lesões. Enfatiza-se o papel do enfermeiro na elaboração de planos de cuidados baseados em evidências para melhor gerenciamento do cuidado.

OBJETIVO

Evaluar el costo directo de curativos para el tratamiento de lesiones por presión.

MÉTODO

Estudio observacional descriptivo en la Unidad de Cuidados Intensivos del noreste de Brasil, de noviembre a diciembre del año 2015. Se aplicó la Pressure Ulcer Scale for Healing y formulario para la caracterización y evaluación de los costos. Los valores de la moneda brasileña (Reales- R$) se convirtieron al dólar estadounidense (US$) a razón de $0.26/R$. Se realizaron análisis univariados y bivariados.

RESULTADOS

La muestra consistió en 15 pacientes con lesiones al menos en Etapa 2. Hubo una reducción significativa en el costo de los materiales de curación entre las evaluaciones inicial y final (p=0,002), con un promedio de US$11.9 (±7.4). Los tratamientos tópicos más comunes son los ácidos grasos esenciales y papaína.

CONCLUSIÓN

Se verificó una reducción de los costos proporcional a las etapas de las lesiones. Se hace hincapié en el papel de los enfermeros en el desarrollo de planes de cuidados basados en la evidencia, para una mejor gestión de la atención.

Topical phenytoin for treating pressure ulcers

BACKGROUND

Pressure ulcers are common in clinical practice and pose a significant health problem worldwide. Apart from causing suffering to patients, they also result in longer hospital stays and increase the cost of health care. A variety of methods are used for treating pressure ulcers, including pressure relief, patient repositioning, biophysical strategies, nutritional supplementation, debridement, topical negative pressure, and local treatments including dressings, ointments and creams such as bacitracin, silver sulphadiazine, neomycin, and phenytoin. Phenytoin is a drug more commonly used in the treatment of epilepsy, but may play an important role in accelerating ulcer healing.

OBJECTIVES

To assess the effects of topical phenytoin on the rate of healing of pressure ulcers of any grade, in any care setting.

SEARCH METHODS

In September 2016, we searched the following electronic databases to identify relevant randomized clinical trials: the Cochrane Wounds Specialised Register; the Cochrane Central Register of Controlled Trials (CENTRAL; the Cochrane Library); Ovid MEDLINE; Ovid Embase; and EBSCO CINAHL Plus. We handsearched conference proceedings from the European Pressure Ulcer Advisory Panel, European Wound Management Association and the Tissue Viability Society for all available years. We searched the references of the retrieved trials to identify further relevant trials. We also searched clinical trials registries to identify ongoing and unpublished studies. There were no restrictions with respect to language, date of publication or study setting.

SELECTION CRITERIA

We included all randomized controlled trials (RCTs) addressing the effects (both benefits and harms) of topical phenytoin on the healing of pressure ulcers of any grade compared with placebo or alternative treatments or no therapy, irrespective of blinding, language, and publication status.

DATA COLLECTION AND ANALYSIS

Two review authors independently selected studies, extracted information on participants, interventions, methods and results and assessed risk of bias using Cochrane methodological procedures. For dichotomous variables, we calculated the risk ratio (RR) with 95% confidence interval (CI). For continuous variables, we calculated the mean difference with 95% CI. We rated the quality of the evidence by using Grading of Recommendations, Assessment, Development and Evaluation approach (GRADE).

MAIN RESULTS

Three small RCTs met our inclusion criteria and included a total of 148 participants. These compared three treatments with topical phenytoin: hydrocolloid dressings, triple antibiotic ointment and simple dressings. In the three RCTs, 79% of participants had grade II ulcers, and 21% of participants had grade I ulcers; no participants had grade III or IV ulcers. Two RCTs had a high risk of bias overall and the other RCT was at unclear risk of bias due to poor reporting. Two RCTs had three intervention arms and the other had two intervention arms.Two studies compared topical phenytoin with hydrocolloid dressing (84 participants analysed). The available data suggest that hydrocolloid dressings may improve ulcer healing compared to topical phenytoin (39.3% ulcers healed for phenytoin versus 71.4% ulcers healed for hydrocolloid dressings (RR 0.55, 95% CI 0.33 to 0.92; 56 participants, 1 study; low quality evidence). We downgraded the evidence twice: once due to serious limitations (high risk of bias) and once due to the small sample size and small number of events. Two studies compared topical phenytoin with simple dressings (81 participants analysed). From the available data, we are uncertain whether topical phenytoin improves ulcer healing compared to simple dressings (39.3% ulcers healed for phenytoin versus 29.6% ulcers healed for the simple dressing (RR 1.33, 95% CI 0.63 to 2.78; 55 participants, 1 study; very low quality evidence). This evidence was downgraded once due to serious limitations (high risk of bias) and twice due to the low number of outcome events and resulting wide CI which included the possibility of both increased healing and reduced healing. We therefore considered it to be insufficient to determine the effect of topical phenytoin on ulcer healing. One study compared topical phenytoin with triple antibiotic ointment, however, none of the outcomes of interest to this review were reported. No adverse drug reactions or interactions were detected in any of the three RCTs. Minimal pain was reported in all groups in one trial that compared topical phenytoin with hydrocolloid dressings and triple antibiotic ointment.

AUTHORS' CONCLUSIONS

This review has considered the available evidence and the result shows that it is uncertain whether topical phenytoin improves ulcer healing for patients with grade I and II pressure ulcers. No adverse events were reported from three small trials and minimal pain was reported in one trial. Therefore, further rigorous, adequately powered RCTs examining the effects of topical phenytoin for treating pressure ulcers, and to report on adverse events, quality of life and costs are necessary.

Backrest Elevation and Tissue Interface Pressure by Anatomical Location During Mechanical Ventilation

BACKGROUND

Backrest elevations less than 30° are recommended to reduce pressure ulcers, but positions greater than 30° are recommended during mechanical ventilation to reduce risk for ventilator-associated pneumonia. Interface pressure may vary with level of backrest elevation and anatomical location (eg, sacrum, heels).

OBJECTIVE

To describe backrest elevation and anatomical location and intensity of skin pressure across the body in patients receiving mechanical ventilation.

METHODS

In a longitudinal study, patients from 3 adult intensive care units in a single institution receiving mechanical ventilation were enrolled within 24 hours of intubation from February 2010 through May 2012. Backrest elevation (by inclinometer) and pressure (by a pressure-mapping system) were measured continuously for 72 hours. Mean tissue interface pressure was determined for 7 anatomical areas: left and right scapula, left and right trochanter, sacrum, and left and right heel.

RESULTS

Data on 133 patients were analyzed. For each 1° increase in backrest elevation, mean interface pressure decreased 0.09 to 0.42 mm Hg. For each unit increase in body mass index, mean trochanter pressure increased 0.22 to 0.24 mm Hg. Knee angle (lower extremity bent at the knee) and mobility were time-varying covariates in models of the relationship between backrest elevation and tissue interface pressure.

CONCLUSIONS

Individual factors such as patient movement and body mass index may be important elements related to risk for pressure ulcers and ventilator-associated pneumonia, and a more nuanced approach in which positioning decisions are tailored to optimize outcomes for individual patients appears warranted.

A Study of the Factors Associated with Risk for Development of Pressure Ulcers: A Longitudinal Analysis

Background:

Pressure ulcers (PUs) are prevalent in hospitalized patients; they may cause clinical, psychological, and economic problems in these patients. Previous studies are cross-sectional, have used pooled data, or cox-regression models to assess the risk for developing PU. However, PU risk scores change over time and models that account for time varying variables are useful for cohort analysis of data.

Aims and Objectives:

The present longitudinal study was conducted to compare the risk of PU between surgical and nonsurgical patients, and to evaluate the factors associated with the development of these ulcers over a period of time.

Materials and Methods:

We evaluated 290 hospitalized patients over a 4 months period. The main outcomes for our analysis were: (1) Score on the pressure risk assessment scale; and (2) the proportion of individuals who were at severe risk for developing PUs. We used random effects models for longitudinal analysis of the data.

Results:

The mean PU score was significantly higher in the nonsurgical patients compared with surgical patients at baseline (15.23 [3.86] vs. 9.33 [4.57]; P < 0.01). About 7% of the total patients had a score of >20 at baseline and were considered as being at high-risk for PU; the proportion was significantly higher among the nonsurgical patients compared with the surgical patients (14% vs. 4%, P = 0.003). In the adjusted models, there was no difference for severe risk for PU between surgical and nonsurgical patients (odds ratios [ORs]: 0.37, 95% confidence interval [CI]: 0.01–12.80). An additional day in the ward was associated with a significantly higher likelihood of being at high-risk for PU (OR: 1.47, 95% CI: 1.16–1.86).

Conclusion:

There were no significant differences between patients who were admitted for surgery compared with those who were not. An additional day in the ward, however, is important for developing a high-risk score for PU on the monitoring scale, and these patients require active interventions.

A new pressure ulcer conceptual framework

AIM

This paper discusses the critical determinants of pressure ulcer development and proposes a new pressure ulcer conceptual framework.

BACKGROUND

Recent work to develop and validate a new evidence-based pressure ulcer risk assessment framework was undertaken. This formed part of a Pressure UlceR Programme Of reSEarch (RP-PG-0407-10056), funded by the National Institute for Health Research. The foundation for the risk assessment component incorporated a systematic review and a consensus study that highlighted the need to propose a new conceptual framework.

DESIGN

Discussion Paper.

DATA SOURCES

The new conceptual framework links evidence from biomechanical, physiological and epidemiological evidence, through use of data from a systematic review (search conducted March 2010), a consensus study (conducted December 2010-2011) and an international expert group meeting (conducted December 2011).

IMPLICATIONS FOR NURSING

A new pressure ulcer conceptual framework incorporating key physiological and biomechanical components and their impact on internal strains, stresses and damage thresholds is proposed. Direct and key indirect causal factors suggested in a theoretical causal pathway are mapped to the physiological and biomechanical components of the framework. The new proposed conceptual framework provides the basis for understanding the critical determinants of pressure ulcer development and has the potential to influence risk assessment guidance and practice. It could also be used to underpin future research to explore the role of individual risk factors conceptually and operationally.

CONCLUSION

By integrating existing knowledge from epidemiological, physiological and biomechanical evidence, a theoretical causal pathway and new conceptual framework are proposed with potential implications for practice and research.

Exploring factors associated with pressure ulcers: a data mining approach

BACKGROUND

Pressure ulcers are associated with a nearly three-fold increase in in-hospital mortality. It is essential to investigate how other factors besides the Braden scale could enhance the prediction of pressure ulcers. Data mining modeling techniques can be beneficial to conduct this type of analysis. Data mining techniques have been applied extensively in health care, but are not widely used in nursing research.

PURPOSE

To remedy this methodological gap, this paper will review, explain, and compare several data mining models to examine patient level factors associated with pressure ulcers based on a four year study from military hospitals in the United States.

METHODS

The variables included in the analysis are easily accessible demographic information and medical measurements. Logistic regression, decision trees, random forests, and multivariate adaptive regression splines were compared based on their performance and interpretability.

RESULTS

The random forests model had the highest accuracy (C-statistic) with the following variables, in order of importance, ranked highest in predicting pressure ulcers: days in the hospital, serum albumin, age, blood urea nitrogen, and total Braden score.

CONCLUSION

Data mining, particularly, random forests are useful in predictive modeling. It is important for hospitals and health care systems to use their own data over time for pressure ulcer risk prediction, to develop risk models based upon more than the total Braden score, and specific to their patient population.