Antimicrobial silver dressings: a review of emerging issues for modern wound care

Abstract

Skin is an important barrier to pathogenic microorganisms and plays a critical role in a ctivation of innate immune responses. When the skin barrier is breached following wounding or burn injury, pathogens can invade and complicate healing with infection resulting in delayed healing and symptomatic scarring. Wound infection is a significant problem after burn injury and in patients with chronic wounds. Antimicrobial silver has had a significant role in wound antisepsis throughout history and, given the rise in community acquired antibiotic resistance, silver dressings are now commonly used to combat wound infection. The multi-modal mechanism of action, low potential for toxicity and formation of microbial resistance makes silver dressings suitable tools against a wide array of clinically important microbes. There are, however, a number of issues with silver dressings including a conflicting evidence base, the important environmental consideration of nanoparticle manufacture, and the significant cost of these products. One solution may be to adopt an 'opened-but-unused' means of wound care whereby bulk dressing materials are used piecemeal and stored in between dressing changes to increase the cost-effectiveness and reduced wastage. There is, however, little literature on this topic and so in vitro and clinical research must be performed to consider the efficacy of active ingredient dressings in wound care including silver dressings once opened and stored.

Evaluating the impact of an anti‐microbial silver‐impregnated surgical dressing on wound infections and healing: A randomised clinical trial

“…These silver ions are highly reactive and bind to various cellular components of bacteria, disrupting their metabolic processes, DNA replication, and cell wall formation. 12 The antibacterial properties of silver dressings are tied to the rate and quantity of silver ion release from the dressing. Recent advancements in nanotechnology have further improved this by encapsulating silver into nanoparticles, significantly increasing the available surface area for silver dissolution and thereby enhancing its antimicrobial efficacy.…”

The fabrication and evaluation of silver nanoparticle-based keratin scaffolds

“…20,21 With the rapid development of nanotechnology in the early of this century, silver enters people’s vision again in the form of nanoparticles. 22 Studies have shown that AgNPs have broad-spectrum antimicrobial properties against pathogens including bacteria, fungi and viruses, 21,23 and have extensive inhibitory activity against antibiotic resistant bacteria. 24 AgNPs achieve their antibacterial purposes by interference with the cell-membrane function, inducing reactive oxygen species (ROS) production of intracellular and trigger the oxidative stress of cell, inhibiting DNA replication and cell division, causing inactivation of the enzyme and protein denaturation.…”

Practical extended use of antimicrobial silver (PExUS)

“…Purchasing dressings in larger sizes is less expensive per square unit area and therefore may improve the cost per dressing change. 15 Because of the lack of evidence on this topic, it is not known whether opened silver dressings oxidize significantly enough over time to affect antimicrobial efficacy.…”

“…The concept of open‐but‐unused dressings is one where larger sheets of dressing material are used in piecemeal fashion with the remaining portion stored in between dressing changes. Purchasing dressings in larger sizes is less expensive per square unit area and therefore may improve the cost per dressing change 15 . Because of the lack of evidence on this topic, it is not known whether opened silver dressings oxidize significantly enough over time to affect antimicrobial efficacy.…”

“…5,6 The multi-modal antimicrobial mechanism of silver provides a broad spectrum and rare chance of microbial resistance. [7][8][9][10] There are, however, issues with silver dressings including a conflicting evidence base with a lack of high-quality clinical trials, 11,12 the important environmental consideration of silver nanoparticle manufacture, 9,13 and a significant fiscal expense 14,15 without clearly demonstrated cost-effectiveness. 16 One strategy that could be used to reduce wastage and improve cost effectiveness would be the adoption of an opened-butunused model of wound care.…”