Pressure Ulcers and Pressure Relief Surfaces

Design for Bedridden Elderly: Presenting Pressure Ulcer Product Design Based on Anthropometric Characteristics

Pressure ulcers are a type of injury that causes tissue ischemia, a deficiency of nutrition and oxygen to the tissues, and, eventually, tissue necrosis when an area of skin is placed under constant pressure for an extended length of time. With the acceleration of the aging process, the problem of providing care for pressure ulcers for the bedridden elderly becomes increasingly urgent. This study conducts a field survey based on the research status of 221 disabled elderly in 16 communities on 7 typical streets in Beijing, focusing on the problem of pressure ulcer complications caused by bedridden. An automatic inflatable airbag mattress is designed according to anthropometric dimensions of bedridden elderly, pressure ulcer-prone areas, and the decompression standard, so that the airbag mattress can reduce the pressure in its initial shape. To achieve accurate control of the pressure in the pressure-prone areas of an airbag, air pressure control system is proposed which can control airbags individually and link multiple airbags, evaluating the safety of pressure ulcer points based on the data from sensors and making corresponding air pressure changes to reduce the possibility of generating pressure ulcers. The proposed pressure ulcer preventing system will be an efficient healthcare tool for families who had elderly bedridden patients, patients with chronic degenerative disease side effects, and terminal and postsurgical patients, as well as femur fractures, in their homes.

Non-surgical treatment for pressure ulcer

Pressure, friction, shear force, and micromoisture can cause pressure ulcer. With the increase of the elderly population in Korea, the number of decubitus pressure ulcer patients is increasing due to worsening medical conditions by aging. In the case of quadriplegic and hemiplegic patients, there is considerable interest in the prevention and self-treatment of pressure ulcer following daily life recovery through rehabilitation. It is important to recognize that pressure ulcer can sometimes be avoided and can sometimes occur inevitably, and that preventive measures should be put in place. For the improvement of pressure ulcer, the patient’s systemic condition and the understanding of indications for local treatment should be improved. Recently, guidelines for dressing formulations related to exudate absorption capacity were introduced. For the successful treatment of pressure ulcer, adequate support of nutrition, control of stiffness, prevention of bacterial bioburden, removal of dead tissue (debridement), moisturizing of the skin, and selection of appropriate dressing materials should be applied comprehensively for individual patients.

Ultrasound elastography reveals the relation between body posture and soft-tissue stiffness which is relevant to the etiology of sitting-acquired pressure ulcers

OBJECTIVE

Sitting-acquired pressure ulcers (PUs) are common in wheelchair users. These PUs are often serious and may involve deep tissue injury (DTI). Investigating the mechanical properties of the tissues susceptible to DTI may help in guiding the prevention and early detection of PUs. In this study, shear wave elastography (SWE) was used to measure the normative mechanical properties of the soft tissues of the buttocks, i.e. skeletal muscle and subcutaneous fat, under the ischial tuberosities, in a convenient sample of healthy adults without weight bearing and with weight bearing of different times.

APPROACH

We compared the stiffness properties of these soft tissues between the lying prone and sitting postures, to determine whether there are detectable property changes that may be associated with the type of posture. We hypothesized that muscle contractions and 3D tissue configurations associated with the posture may influence the measured tissue stiffnesses.

MAIN RESULTS

Our results have shown that indeed, SWE values differed significantly across postures, but not over time in a specific posture or for the right versus left sides of the body.

SIGNIFICANCE

We have therefore demonstrated that soft-tissue stiffness increases when sitting with weight bearing and may contribute to increasing the potential PU risk in sitting compared to lying prone, given the stiffer behavior of tissues observed in sitting postures.

FINITE ELEMENT PREDICTION OF SUB-DERMAL TISSUE STRESSES OF THE BUTTOCKS DURING WHEELCHAIR PROPULSION

Pressure ulcers, involving sub-dermal tissue damage and originating in deep tissue injury (DTI), have attracted much attention of physicians and researchers for three decades. Finite element (FE) model is a very efficient tool to investigate internal stresses and strains in human body that induce pressure ulcers. However, there was scarce report available to explore stresses distribution in human buttocks during manual wheelchair propulsion. A three-dimensional (3D) comprehensive FE model, incorporating ischial tuberosities (ITs), muscle, fat, and custom-contoured cushion (CCC), was developed to investigate internal stress distribution in soft tissue of the buttocks. Based on the FE model, pressure distribution under ITs in static sitting and during different wheelchair propulsions is studied. Internal stresses in fat and muscle were about three times and five times higher than that on cushion surface in terms of static sitting and wheelchair propulsion. All peak pressures under wheelchair propulsion were higher than those of static sitting, and peak pressures went on increasing with increase of wheelchair movement speed. This method based on the comprehensive FE model allowed for the optimization of wheelchair seat cushion design.

Magnetic resonance imaging of pressure sores in spinal cord injured patients: accuracy in predicting osteomyelitis

OBJECTIVE

Identify key magnetic resonance imaging (MRI) features that have a significant correlation with osteomyelitis of pressure ulcers in spinal injury patients.

DESIGN

Retrospective review study.

PARTICIPANTS

Adult patients admitted to the National Spinal Injuries Centre with spinal cord injury (SCI) and signs of pressure ulceration investigated with MRI.

METHODS

Analysis of MRI examinations and clinical records collected over a 4-year period. Images were independently assessed by 2 experienced radiologists for osteomyelitis based on assigned predictive indicators including cortical bone erosion, soft tissue edema, deep collections, heterotopic new bone, hip effusion, and abnormal signal change of the marrow.

RESULTS

Thirty-seven patients underwent 41 MRI scans. The prevalence of osteomyelitis was highly correlated with cortical bone erosion (r = 0.84) and abnormal bone marrow changes on T1-weighted images (r = 0.82).

The use of sensory electrical stimulation for pressure ulcer prevention

Pressure ulcer prevention is critically important for many people with reduced mobility. The authors investigated whether sensory (sub-motor-threshold) electrical stimulation (ES) may provide a convenient preventive intervention. A double-blinded, repeated measures study design was used to test the hypothesis that repeated use of sensory surface ES improves tissue health status in individuals with motor paralysis. Six adult males with complete spinal cord injury (SCI) were randomly assigned to treatment or control groups. The treatment group received the ES intervention, whereas the control group received a control sham intervention. Repeated tissue health assessments included transcutaneous oxygen tension (T(c)PO(2)), interface pressure mapping, and gluteal computed tomography (CT) studies. An initial increase in T(c)PO(2) following use of subthreshold ES was observed but was not sustained at follow-up. No statistically significant changes before and after treatment were found in regional T(c)PO(2), gluteal muscle area or pressure distribution. Thus subthreshold ES does not appear to have any sustained effects on tissue health status indicative of reduced pressure ulcer risk for individuals with SCI. This implies that a contractile muscle response is critically important and further that subthreshold ES is unlikely to prevent pressure ulcers. Further studies are needed to find solutions for preventing pressure ulcers in high-risk populations.

Evaluation of the effect of trunk tilt on compressive soft tissue deformations under the ischial tuberosities using weight-bearing MRI

BACKGROUND

Deep tissue injury is the new acceptable term for deep pressure ulcers. Deep tissue injury of the buttocks is typically caused by sustained soft tissue deformations under the ischial tuberosities. Wheelchair users are at high risk, and although usually laterally tilted, the effect of tilts on tissue deformations is unknown. This has brought us to investigate buttocks tissue compressive deformations between the ischial tuberosities and skin during sitting in various body tilts, utilizing weight-bearing Magnetic resonance imaging (MRI).

METHODS

Ten healthy volunteers underwent sitting MRI, in six postures including neutral with/without weight-bearing, 10 degrees and 20 degrees lateral-tilts, and 20 degrees and 40 degrees anterior tilts. Studies utilized a coronal T1-weighted sequence. Images were evaluated for thickness of tissues between the skin and the lowest point of the ischial tuberosity, of fat between the skin and the gluteus muscle and of muscle between the ischial tuberosity and fat. Measurements in weight-bearing positions were compared to the non-weight-bearing for calculation of compressive tissue deformations in each trunk tilt. Statistical analysis was obtained utilizing multiple pairwise t-tests with Bonferroni corrections.

FINDINGS

Muscle and soft tissue compressive deformations, from highest to lowest, were 20 degrees -lateral-tilt (87%, 72%), lateral-10 degrees (85%, 70%), anterior-20 degrees (79%, 67%), anterior-40 degrees (74%, 64%), and neutral (72%, 59%). For the fat, highest was anterior-tilts (42%), followed by lateral-20 degrees -tilt (41%), lateral-10 degrees (39%) and neutral (35%).

INTERPRETATION

For lateral tilts, the higher the angle was, the higher the compressive deformation was. However, the most profound change in compressive deformation occurred at the small angle tilts.

Special issues in plastic and reconstructive surgery

Intensivists frequently collaborate with plastic and reconstructive surgeons in treating patients with major wounds, following significant reconstructive procedures, and following free-tissue transfers. Pressure ulcers are a significant source of morbidity and mortality in the intensive care unit; prevention, early recognition, and multidisciplinary treatment are critical components for successful management. Necrotizing fasciitis is an aggressive, soft-tissue infection that requires rapid diagnosis, early surgical intervention frequent operative debridements, and soft-tissue reconstruction Catastrophic abdominal injuries and infections can be treated with an open abdominal approach and require the expertise of a plastic surgeon to reconstruct the abdominal wall. The success of free-tissue transfers and complex reconstructive procedures requires a thorough understanding of the factors that improve flap survival.

Factors influencing the development of decubitus ulcers in critically ill surgical patients

INTRODUCTION

Decubitus ulcers confer significant morbidity to critically ill patients. We sought to determine which patient factors contributed to the formation of decubitus ulcers in our critically ill patients, and hypothesized that these ulcers occurred most often in elderly patients with lengths of stay >7 days and high severity of illness.

METHODS

This study was conducted prospectively in two phases. Phase I provided an initial analysis of patients who developed decubitus ulcers in the surgical intensive care unit (ICU) of New York Weill Cornell Center from January 1, 1993, to June 1, 1997. In phase II of the study, a comparison study was made for patients with ICU length of stay (ULOS) >7 days admitted to the same ICU from January 1, 1998, to August 31, 1998. Age, APACHE III score, systemic inflammatory response syndrome (SIRS score), multiple organ dysfunction syndrome (MODS) score, admission status, days without nutrition, ULOS, mortality, days to formation of decubitus ulcers, Cornell ulcer risk score, and other demographic features were recorded. Univariate and multivariate analysis of variance were performed to analyze independent risk factors for development of decubitus ulcers; p <.05.

RESULTS

In phase I, 2,615 patients were admitted to surgical ICU over the study period. One hundred and one decubitus ulcers occurred (incidence 3.8%) during phase I, but the incidence of decubitus ulcers increased significantly over time to 9% (p <.01). Thirty-three decubitus ulcers occurred among the 412 patients (incidence 8.0%) during phase II. Multivariate analysis revealed that emergent admission (odds ratio [OR] 36.00, 95% confidence interval [CI] CI 0.2290-0.7694), age (OR 1.08, 95% CI 0.0026-0.0131), days in bed (OR 1.05, 95% CI -0.0013-0.0156, and days without nutrition (OR 0.51, 95% CI -0.1095--0.0334) were independent predictors of a decubitus ulcer.

CONCLUSIONS

The incidence of decubitus ulcers is increasing in critically ill patients. Emergency ICU admission and ULOS >7 days in elderly patients confer significant risk for the formation of decubitus ulcers. Specific interventions targeting this high-risk population that may be instituted to decrease the incidence of decubitus ulcers include early nutrition, early mobilization, and possibly less noxious bedding surfaces.

Skin ulcer at the blunt apex of a giant Warthin's tumor

An unusual finding of Warthin's tumor or papillary cystadenoma lymphomatosum with ulceration of the overlying skin is described in a patient who refused surgical removal of this growth. The present article is the second case published in the English language dermatological literature on this fascinating tumor. To our knowledge, the clinical presentation and course of the disorder in this individual are unique.

Prevalence and characteristics of pressure ulcers. A one-day patient population in a Finnish city

This article discusses the prevalence and characteristics of pressure ulcers in a one-day patient population in a Finnish city. The data was collected using two questionnaires. Data analysis was based on percentage distributions; statistical significances were tested with the Chi-square test. The measurement identified 186 patients with a total of 300 pressure ulcers. The majority (90%) of these patients were hospitalized and 10% were in outpatient care. The main causes for the development of pressure ulcers were inadequate turning and positioning and the patient's primary illness. Most of the ulcers were grade II. Only a few patients had ulcers that exposed bone. The preventive effort should extend from the nursing unit level, through the organizational level, to the level of society as a whole. It should consist of the identification of people at high risk for pressure ulcers and the provisions of quality care for these people.