The recent 21st Annual Symposium on Advances and Skin and Wound Care in Lake Buena Vista, FL, was truly a multidimensional success. As a course participant, I was excited by the many opportunities the conference offered for advancing our knowledge in the field of skin and wound care.
Symposium attendees were enthusiastic about the variety of topics presented during the 3-day event. The energy was palpable-from those participating in collegial discussions, to the atmosphere in the general and breakout sessions, to the cutting-edge satellite topics and poster presentations.
One topic of great interest at the conference was the increased use of silver products and the trend toward combination products that include silver. In the exhibit hall, the enthusiasm generated for these types of products was a reflection of the manufacturers' quest to provide true advances in wound care. Such advances require an investment in research, clinical investigation, manufacturing, marketing, public policy, and, of course, clinical applicability at the point of service. Both clinicians and product manufacturers have a stake in providing the best possible dressing materials and preparations to effectively manage patients with chronic wounds. Silver is emerging today as a popular treatment, but in reality, it has been used in medicine and wound care for centuries.
From Antiquity to Modern Day
Hippocrates, the father of medicine, documented the beneficial healing and disease-modifying properties of silver. The Phoenicians stored water and wine in silver vessels to prevent the liquids from spoiling. In the early 1900s, people often deposited silver dollars in milk bottles to prolong the milk's freshness.
Before the advent of penicillin, clinicians placed silver wafers on contaminated wounds during World War I to help prevent infection. The widespread use of silver, however, diminished following the development of modern antibiotics. Recently, a renewed interest in using silver as a broad-spectrum antimicrobial has emerged.
Topical silver sulfadiazine 1% cream has a long record of successful use in medicine. This preparation is safe and effective as a burn treatment, and it is a valuable agent against Pseudomonas. Silver is also used in combination with other devices, compounds, and dressings to enhance the wound environment for healing. For example, today, we see silver being used with alginate, a naturally occurring biopolymer derived from seaweed, in a range of silver alginate products designe d to prevent infections as part of wound care management plan. Novel silver-based dressings, some of which provide a sustained release of silver ions to the wound bed, have recently become available.
Silver's Antimicrobial Effects
Silver has a demonstrative effect in vitro on a broad range of bacteria (including methicillin- and vancomycin-resistant strains), yeast, fungi, and viruses. Although silver's germicidal effects kill many microbial organisms in vitro, researchers can only theorize about its mode of action. One such theory involves a process generally associated with heavy metals, known as the oligodynamic effect (the denaturing of proteins and enzymes). This may explain the effect silver has on microbial organisms, but it does not explain certain antiviral functions. Other heavy metals, such as lead or mercury, have a similar toxic effect on some bacteria, viruses, algae, and fungi; however, they also have well-known toxic effects on the body.
Silver does not pose the toxic threat to humans that is normally present with other heavy metals. It is taken up in the intestine and passed through the blood, liver, and bone marrow, and, ultimately, is excreted in urine. Silver and compounds containing silver (like colloidal silver) can be absorbed into the circulatory system and become deposited in various body tissues. This can lead to argyria, which results in a blue-grayish pigmentation of the skin, eyes, and mucous membranes. Although this condition does not harm an individual's health, it is disfiguring and usually permanent. Argyria is rare, and mild forms are sometimes mistaken for cyanosis.
Strength of Evidence
New silver compounds and delivery systems have the potential to improve wound care outcomes. Yet more evidence is needed about the safety and efficacy of many of the recently developed topical silver products. Articles in the literature summarize the available information on the safety and efficacy of topically delivered silver compounds. These articles can be useful as a resource for wound care professionals when making decisions regarding the use of topical silver products.
The wound care industry is making progress in repackaging silver by using advanced technology and partnering with clinicians to make a vintage product even better. This is indeed a silver lining in the war against wounds.
References