When I began my training at Crawford (Doylestown, PA), I was introduced to a new portfolio of products. Two contain a novel silver compound, Ag Oxysalts™, whose mechanism of action (MOA) challenged my knowledge about silver in wound care practice. To learn more, I assessed them as I would any product.
I find it intuitive to start with some basic objective questions and considerations. These general questions and their answers lead me to a more comprehensive evaluation plan. For example, I ask, “Does this product have similar indications for use as products I am currently using in my practice?” If the answer is yes, I address more indepth considerations before deciding to use the new product. Ag Oxysalts is an example of a product for which it is important to critically evaluate the MOA.
Elemental silver in the Ag0 format is a stable molecule and is relatively nonreactive. However, through technology developments in the 1990s, elemental silver was modified to ionic silver, a more reactive version and the only form of antimicrobial silver. This technology provided a way for silver compounds to be delivered in dressings and broken down into ions when exposed to wound fluid or an aqueous solution. The ions are an Ag1+ electron format and can kill bacteria by rupturing the cell wall, inhibiting vital enzymes, destroying cells using silver-free radicals, or interacting with the bacteria’s DNA. The MOA of newly engineered Ag Oxysalts (Ag7NO11) technology makes highly oxidative states of silver ions (Ag1+, Ag2+, Ag3+) available; thus, the silver is more powerful and can work faster while using a fraction of the amount of silver compared to other ionic silver formats1,2 (see Figure 1).
After my review of the MOA, I developed questions that would help me analyze the value of this new technology. These questions are based on my experiences using silver dressings in clinical practice and teaching the antimicrobial properties of silver in pre- and post-professional coursework. Because of the historical challenges regarding the use of silver dressings in the literature, my questions were related to cytotoxicity and healthy tissue, resistance of microbes to silver, and the ability to disrupt a biofilm, not just planktonic bacteria.