Silver Dressings (Ag) for Wound Healing and Skin Care
Silver, found in Silver Wound Dressings, is a basic element on the Periodic Table with the abbreviation of "Ag." It has the highest electrical and thermal conductivity of any element. It is an active agent or antimicrobial against a broad spectrum of bacteria and other harmful microorganisms. It is also an agent for anti-inflammation. Ag is useful in wound coverings because of its ability to fight infections and reduce inflammation. Silver Wound Dressing applications include films, foams, gels, creams, knitted polyester, and cellulose fibers. The use of Silver to treat wounds is effective for up to two to three weeks. It promotes a moist environment that supports healing. Treatment applications combined with alginates (Silver Alginate Dressings), charcoal, hydrocolloids, hydrogels, and composites bring additional benefits to healing.
Ag coverings are medically proven to help with burn wounds as well as other standard wound care. Though it's most effective against dermal wounds and abrasions, Ag products topically treat acute and chronic exudating injuries. Numerous Ag medical studies find that these wound treatment products have antimicrobial applications.
Silver has proven antimicrobial activity that includes antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Its role as an antimicrobial agent is particularly effective, as it has a broad spectrum of antimicrobial activity with minimal toxicity. It is less likely than antibiotics to induce resistance due to its activity at multiple bacterial target sites.1 "It is widely accepted that resistance to antimicrobials has increased through the overuse and misuse of systemic antibiotics. The use of topical antimicrobial dressings in the field of wound care is now undergoing a revival and there is a multitude of products available containing a range of agents that are broad-spectrum antimicrobials (primarily honey, silver, and iodine)."2
Below are the key advantages and disadvantages that Ag treatments offer.
- Reduces infections
- Slow-release of active ingreient
- Provides moist wound environment
- Promotes blood vessel formation
- Less frequent dressing changes
- Fewer pain medications for bandage changes
- Faster wound healing
- Shorter hospital recovery periods
- Can mask signs of infection
- Short usage period of 2 to 3 weeks
- Dries easily
- May stain peri-wound tissue
- Cannot be used with topical medications
- May cause stinging
- May cause sensitization
Adherent/Non-Adherent: Ag applications come in many shapes and sizes but still provide options for patient preferences. Wound coverings that have an adhesive border allow the patient or the medical professional to adhere the bandage to the skin, lessening the need for a secondary bandage. Adhesive border wound coverings can save time and money. It takes less time to change an adhesive-type dressing. Non-adhesive coverings take more time but are often necessary for difficult to bandage areas of the body. Sometimes patients require a special primary dressing because of the wound type or wound location, so a non-adherent style dressing is not elective, and therefore, a secondary bandage secures the primary dressing in place.
Shapes and Sizes: Silver wound coverings come in many shapes and sizes. From rectangular and square to sacral- and heel-shaped, silver wound treatments fit just about anywhere on the body. Standard square shapes can measure anywhere from 2 x 2 inches up to 8 x 8 inches. Rectangular will yield a 2-inch wide piece and will run up to 8 inches in length or longer. Rope dressing are another dressing type for wound cavities. All of these options combine to offer a host of solutions for wound bandaging.
Topical Silver Ointments: Gels and creams are available with silver to aid in treating infectious wounds. These topical applications apply directly to the skin and wound surface. Gels make full contact with the wound bed, letting it kill off bacteria faster than a bandage or a hydrogel. Often, these applications allow for faster wound healing.
The right kind of Ag wound application can give you a leg up on healing infected wounds and abrasions. See our Buying Guide for Silver Dressings for more information.
What is a silver antimicrobial dressing?
Ionic Ag added to a wound covering slowly releases the active ingredient upon activation by exudate or bacteria. This sustained delivery eliminates the risk of toxicity to the wound and surrounding tissue. It kills bacteria and does not allow it to form chemical bonds to multiply. It also acts as a barrier to harmful organisms like MRSA. The appearance of an Ag application is set apart from most other wound coverings because of its gray color. Although many manufacturers have the external side of the wound covering colored differently, the dressing that faces the wound is always gray.
Ag treatments are available in three different formats.
- Nanocrystalline silver
- Compounded with an oxide, phosphate, chloride, sulfate, calcium-sodium phosphate, or zirconium
- Complexes like silver-zinc allantoinate, silver alginate, or silver carboxymehylcellulose
When should silver dressings be used?
The increasing resistance of bacteria to antibiotic treatments helps make Ag a viable option to treat infected wounds. Silver acts as a topical antiseptic rather than as a true antibiotic. It works as an antimicrobial, killing, or preventing the reproduction of bacteria, fungi, and other harmful microorganisms. Because of its antiseptic nature, silver has a low risk of bacterial resistance. Bacterial resistance to antibiotics is a growing problem that limits the options available to treat infectious wounds.
Dressings impregnated with Ag aid with treating infectious and colonized wounds. Wounds in which there is a heavy biofilm environment that requires treatment with a semi-occlusive dressing to form a warm and moist healing environment. "The selection of an appropriate wound dressing should be based on an assessment of the wound and an understanding of properties of various wound dressings. Commonly used wound dressings can be categorized as moisture-retentive and antimicrobial-impregnated dressings, with subtypes of dressings in each category being appropriate in various clinical scenarios. The most appropriate dressing type may change as the wound heals."3
- Primary or secondary dressing for minimal to heavy exudate for both acute and chronic wounds
- Surgical wounds
- Diabetic foot ulcers
- Pressure ulcers
- Leg Ulcers
- Contaminated burn
- Clinically infected burns
- Deep or full-thickness burns
- Burns of mixed or unknown depth
- Minor burns with larger surface areas
- Necrotizing fascitis
- Toxic epidermal necrolysis
- Pilonidal sinus
- Clean surgical wounds
- Closed surgical wounds
- Low risk of infection
- Donor sites
- Small acute wounds with low risk of infection
- Sensitivity to metals or silver
- Wounds requiring enzymatic debridement
- Magnetic resonance imaging (MRI)
- Electrical stimulation (EMS/NMS/TENS)
Cost of Silver Dressings
The actual amount of Ag used in a wound covering is small. Balancing the cost of these wound coverings with the loss of reduced productivity, impaired quality of life, and social isolation is a consideration. Generally, silver wound treatments are "no more expensive than other types of antimicrobial dressings."4 Additionally, silver wound coverings have longer wear times than many other wound treatments, thereby also reducing total expenditures.
How does silver work in a wound dressing?
In its metallic or elemental form, silver is unreactive and cannot kill bacteria. To become bactericidal, silver atoms (denoted as Ag or Ag0) must lose an electron and become positively charged silver ions (Ag+). Elemental silver ionizes in the air but ionizes more readily when exposed to an aqueous environment such as wound exudate. In contrast, silver compounds contain positive silver ions bound to negatively charged ions or molecules. When exposed to aqueous environments, some of the silver ions become detached from the compound. Silver ions are highly reactive and affect multiple sites within bacterial cells, ultimately causing bacterial cell death. They bind to bacterial cell membranes, causing disruption of the bacterial cell wall and cell leakage. Silver ions transported into the cell disrupt cell function by binding to proteins and interfering with energy production, enzyme function, and cell replication. Silver ions are active against a broad range of bacteria, fungi and viruses13, including many antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococci (VRE)".5
Silver has proven antimicrobial activity that includes antibiotic-resistant bacteria, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococci (VRE). Its role as an antimicrobial agent is particularly attractive, as it has a broad spectrum of antimicrobial activity with minimal toxicity toward mammalian cells at low concentrations and has a less likely tendency than antibiotics to induce resistance due to its activity at multiple bacterial target sites.6
- 1 Parsons, David, et al. "Silver antimicrobial dressings in wound management: a comparison of antibacterial, physical, and chemical characteristics." Wounds-A Compendium of Clinical Research and Practice 17.8, 2005. page 222.
- 2 Fletcher, Jacqui. "Antimicrobial dressings in wound care." Nurse Prescribing 4.8, 2006. page 320.
- 3 Adis Medical Writers [email protected] adis. com. "Select appropriate wound dressings by matching the properties of the dressing to the type of wound." Drugs & Therapy Perspectives 30, 2014. page 213.
- 4 Leaper, David. "Appropriate use of silver dressings in wounds: international consensus document." International wound journal 9.5, 2012. page 463.
- 5 Leaper, page 464.
- 6 Parsons, page 222.
- Fujiwara, Toshihiro, Ko Hosokawa, and Tateki Kubo. "Comparative study of antibacterial effects and bacterial retentivity of wound dressings." Eplasty 13 (2013).
- Fletcher, Jacqui. "Antimicrobial dressings in wound care." Nurse Prescribing 4.8 (2006): 320-326.
- Michaels, J. A., et al. "A prospective randomised controlled trial and economic modelling of antimicrobial silver dressings versus non-adherent control dressings for venous leg ulcers: the VULCAN trial." Health Technol Assess 13.56 (2009): 1-114.
- Toy, Lily W., and Liz Macera. "Evidence‐based review of silver dressing use on chronic wounds." Journal of the American Academy of Nurse Practitioners 23.4 (2011): 183-192.
- White, Richard, and Keith Cutting. "Exploring the effects of silver in wound management-What is optimal?." Wounds 18.11 (2006): 307.
- Carter, Marissa J., Kimberly Tingley-Kelley, and Robert A. Warriner III. "Silver treatments and silver-impregnated dressings for the healing of leg wounds and ulcers: a systematic review and meta-analysis." Journal of the American Academy of Dermatology 63.4 (2010): 668-679.