Keeping Patients Under the Damage Threshold for Pressure Injury: Addressing Microclimate Through Allostasis.

BACKGROUND: Pressure injuries (PI) are an ongoing problem in health care. Current interventions, both from clinicians and support surface technologies, do not sufficiently address PI prevention. PROBLEM: Patient microclimate is a contributing risk factor for PI, one which can be more adequately addressed. However, the acceptable range for microclimate is unknown, in part because the body adapts to changing conditions. APPROACH: Two key concepts in allostasis are finite resources and responding to intrinsic and extrinsic demands. These concepts have not previously been applied to PI treatment or interventions. Addressing microclimate, when coupled with an increasing awareness of the cumulative effect of individual patient risk factors, can help resolve the risk of PI by lowering the cumulative inputs to keep patients under the threshold for tissue damage. CONCLUSION: This new approach, which places microclimate risk into the broader conceptual framework of allostasis, can produce more effective products and interventions to prevent PI.

Results of Laboratory Testing for Immersion, Envelopment, and Horizontal Stiffness on Turn and Position Devices to Manage Pressure Injury.

BACKGROUND: A continuing complication, pressure injuries are due to sustained mechanical loading and tissue deformations, which can then be exacerbated by additional intrinsic and extrinsic risk factors. Although support surfaces are designed to mitigate risk factors for pressure injuries, the presence of a turn and position device (TPD) between the patient and support surface may interfere with how support surfaces affect these risk factors. OBJECTIVE: Report the use of the NPIAP's S3I standard test methods to characterize the performance of a support surface when used in conjunction with three different TPDs. DESIGN: Laboratory testing compared three TPDs for Immersion, Envelopment, and Horizontal Stiffness in each of five surface combinations. MAIN OUTCOME MEASURE: Immersion test measures how far mannequin indenter immerses into surface. Envelopment test measures immersion and pressure distribution with hemispherical-indenter with mounted sensor rings. Horizontal Stiffness test measures the shear modulus of the support surface with epicondyle indenter. MAIN RESULTS: For the specific TPDs tested here, the one with an adjustable integrated air bladder improved rather than compromised both the envelopment and the immersion of the support surface alone. Additionally, this TPD provided potential protection against sliding and the associated frictional shear forces. CONCLUSIONS: This paper describes how TPDs should perform in order to help establish which features are needed in a new medical device of this type. Laboratory testing demonstrates it is possible to improve performance of a support surface by applying a TPD as an add-on, thus relieving tissue deformation exposure through more effective pressure redistribution.

New Clinically Relevant Method to Evaluate the Life Span of Prophylactic Sacral Dressings.

It has been demonstrated that wound dressings provide a protective effect against pressure injuries. However, no method exists to measure either the life or performance of dressings used in prevention; testing dressings in a clinical setting or a research environment has typically been based on measuring its moisture absorption capacity. This article examines the changes that occur in the structural and mechanical properties of a prophylactic dressing based on conditions of use when wound exudate is not present.A clinically relevant method was developed to simulate the loading, friction-inducing shear, and moisture transpiration present in a typical hospitalization where a dressing is applied for prevention. Single-use dressings were tested using this method to evaluate their ability to protect patients from pressure injuries throughout the typical 5 to 7 days of use. Following this aging process, researchers measured the physical, structural, and mechanical changes in prophylactic dressings over time.This innovative method provides guidance for clinicians on dressing use and replacement intervals. For bioengineers, the method generates important empirical data for computer modeling of dressing performance, which can then reveal the consequences of changes in dressing structure and function on sustained tissue loads. It is the authors' hope to generate discussion about the creation of industry-wide standards for testing dressings to improve patient care.

Measuring Tensile Strength to Better Establish Protective Capacity of Sacral Prophylactic Dressings Over 7 Days of Laboratory Aging.

Results from large-scale randomized clinical trials support the application of prophylactic dressings to provide protection from body-weight force-induced deformations known to damage skin and underlying tissues, which often result in pressure injuries (pressure ulcers). This laboratory study using a new method for aging dressings in simulated use followed by tensile testing was conducted to further understand the protective effect of sacral prophylactic dressings (SPDs) in alleviating tissue deformations in the sacral region through the course of typical application. Specifically, four SPDs were exposed to a simulation of the clinical environment incorporating saline solution absorption, mechanical loading, and repetitive sliding-induced shear. After aging, the protective endurance of the SPDs was measured through tensile testing to determine their effectiveness against tissue-damaging forces over time.This study uses the concepts of axial stiffness, protective endurance, and elastic limit to describe more accurately the protective aspects of SPDs under dry and moist conditions and how they interact with the skin and underlying tissues over the life of the dressing. The authors propose two primary features in SPD effectiveness in preventing pressure injuries: high conformability (ie, low flexural stiffness) and protective endurance (the dressing's capacity to maintain biomechanical performance when moist).