Mechanizm of Action
SilverStream is a clear, neutral pH hypertonic aqueous solution, which helps in the mechanical removal of foreign material including dirt and debris, exudates and microorganisms from the application site. It serves as a liquid dressing by providing a physical barrier against outside bacterial contamination. SilverStream is cleared by the US FDA as a medical device (K093227) due to its physical mode of action described in the following section:
SilverStream may be administered by pouring the solution directly from the bottle, applying by means of a syringe or bulb, spraying onto the wound using a spray bottle, applying with devices designed to allow for irrigation or lavage, or by pouring onto a gauze/dressing or sponge for cleansing and dressing the wound. Typically, the SilverStream solution is applied via a syringe with 19-22G needle, which creates a pressure between 4-15 psi over the wound bed. Thus, the methods of application of SilverStream allow for the mechanical removal of foreign material.
Primarily, foreign materials are mechanically removed through irrigation, from the application site, as the fluid moves across the wound bed (flushing action). The surfactant in the solution reduces the surface tension and thereby additionally assists with the mechanical removal of foreign material. The hypertonic nature of the solution (containing 10%V/V glycerol) further supports the mechanical removal of bacteria and foreign material by the physical withdrawal of liquids (liquids absorption), which is also supported by the hygroscopic properties of glycerol. In addition, due to its humectant properties, glycerol helps to moisturize the wound bed/application site.
SilverStream solution contains a low concentration ionic silver (0.01%), which acts as a preservative, to control the growth of bacteria, yeast and fungi such as Eschericha coli, Staphylococcus epidermidis, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger.
Menthol is included in the solution, at a concentration of 0.05%, which is below the lowest active concentration for topical use (0.08%) and is intended to provide pleasant odor to the solution and to fight the bad odor of the wounds.
After cleansing the wound, SilverStream soaked gauze is applied on or into the wound to provide a physical barrier against outside bacterial contamination.
In summary, the SilverStream solution is designed to achieve its medical device primary mode of action (PMoA); primarily, the mechanical streaming of the hypertonic solution across the wound surface for removal of foreign objects, including dirt, debris and micro-organisms, as well as being applied as a physical barrier from outside bacterial contamination, supported by its preservative property to prevent wound contamination.