The importance of the simulated wound fluid composition and properties in the determination of the fluid handling performance of wound dressings.

Effective fluid handling by wound dressings is crucial in the management of exuding wounds through maintaining a clean, moist environment, facilitating healing by removing excess exudate and promoting tissue regeneration. In this context, the availability of reliable and clinically relevant standardised testing methods for wound dressings are critical for informed decision making by clinicians, healthcare administrators, regulatory/reimbursement bodies and product developers. The widely used standard EN 13726 specifies the use of Solution A, an aqueous protein-free salt solution, for determining fluid-handling capacity (FHC). However, a simulated wound fluid (SWF) with a more complex composition, resembling the protein, salt, and buffer concentrations found in real-world clinical exudate, would provide a more clinically relevant dressing performance assessment. This study compared selected physicochemical parameters of Solution A, an alternative, novel simulated wound fluid (SWF A), and a benchmark reference serum-containing solution (SCS) simulating chronic wound exudate. Additionally, FHC values for eight advanced bordered and non-bordered foam dressings were determined for all three test fluids, following EN 13726. Our findings demonstrate a close resemblance between SWF A and SCS. This study highlights the critical importance of selecting a physiochemically appropriate test fluid for accurate FHC testing resulting in clinically meaningful evaluation of dressing performance.

Fluid handling by foam wound dressings: From engineering theory to advanced laboratory performance evaluations.

This article describes the contemporary bioengineering theory and practice of evaluating the fluid handling performance of foam-based dressings, with focus on the important and clinically relevant engineering structure-function relationships and on advanced laboratory testing methods for pre-clinical quantitative assessments of this common type of wound dressings. The effects of key wound dressing material-related and treatment-related physical factors on the absorbency and overall fluid handling of foam-based dressings are thoroughly and quantitively analysed. Discussions include exudate viscosity and temperature, action of mechanical forces and the dressing microstructure and associated interactions. Based on this comprehensive review, we propose a newly developed testing method, experimental metrics and clinical benchmarks that are clinically relevant and can set the standard for robust fluid handling performance evaluations. The purpose of this evaluative framework is to translate the physical characteristics and performance determinants of a foam dressing into achievable best clinical outcomes. These guiding principles are key to distinguishing desirable properties of a dressing that contribute to optimal performance in clinical settings.