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acterial infection is one of the primary reasons for slow or poor healing and prolonged inflammation in chronic wounds. Many commonly used antiseptics and antimicrobial agents are known to reduce bacteria but are capable of producing a sluggish wound healing process due to their toxicity to cells. Are you looking for the silver bullet, something new to help you combat these wound-dwelling rogues? You probably remember learning the Golden Rule as a child. Are you familiar with the "Silver Rule," your new long-term care mantra? It's a comprehensive wound management necessity and goes like this, "Never place anything in a wound that could potentially harm it. When contamination or infection is present, consider a natural antimicrobial without negative effects--ionic silver."
       Recently, technological advances have made a natural antimicrobial agent, ionic silver, realistic for wound care. Ionic silver, because of problems with instability, has been difficult to place in a form that is practical for use for wound care until recently. Silver dressings are now readily available and practical for use in wound care, both for infected and vulnerable wounds.

We've Come a Long Way, Baby!
       Healing has always produced competition within wounds: the natural resident bacteria that cause infection versus the ability of the host to fight the bacteria and achieve closure. Individuals with nonhealing wounds often have multiple complex illnesses, immunosuppression, and malnutrition that diminish their healing ability. To achieve healing, wounds must move through an orderly process of coagulation, inflammation, granulation/proliferation, and maturation. Wounds are likely to be "stuck" in the inflammatory phase if there are excessive bacteria present, if the host has poor immune responses to deal with the bacteria, or if the wound is infected. Wound infections complicate treatment and delay wound closure, impair tensile strength of the tissue, increase length of stay and costs of treatment, and additionally increase the resident's risk of sepsis, multisystem failure, and death.1 Acute wounds will not heal until any infectious process is controlled.2
       In the past, eliminating bacteria involved the use of antiseptic and antimicrobial products to decontaminate these wounds. Many topical antimicrobials (e.g., povidone iodine, hydrogen peroxide, sodium hypochlorite) are toxic to cells and can delay healing.3,4 The challenge for topical wound management is to eliminate most of the bacteria and microbes in a manner that does not harm living cells. These agents not only may have some local toxicity, they are also capable of increasing the likelihood for development of antibiotic-resistant microbes. A growing number of bacteria have already become resistant to one or more antibiotics. The Centers for Disease Control and Prevention (CDC) attributes this to over use of antibiotics prescribed without caution.5 Many infected patients now need more complicated treatment with toxic, as well as expensive, medications. The CDC recommends treating only infected wounds with antibiotics, not wounds that are merely contaminated or colonized.
       Another issue with the use of these topical antiseptic products is increased risk of litigation.6 Since national guidelines for wound care discourage the use of antiseptics, use of them may be a red flag for attorneys to pursue lawsuits against the caregivers who use them. There are, however, safe alternative options available for the treatment of infected chronic wounds and their symptoms, including the use of antimicrobial dressings.

Silver's History
       Silver is a commonly found element on earth. It is known as a "noble metal," along with gold and platinum. It has always been considered a precious metal and used for adornment, such as in jewelry. Silver is found in drinking water and foods. The average adult will consume 90mcg daily.7 Silver has been used for its health benefits throughout history, having a long medical and antimicrobial history. Silver coins were used in water vessels since 100 BC to keep liquids fresh. Liquid silver preparations were consumed in the 19th century to maintain health and avoid contagious disease.
       The antimicrobial effect of silver was first discovered in the 1860s. Silver ophthalmic drops were first used for prevention of infection in newborns in the 1880s. Use of silver slowed down with the advent of antibiotics, such as penicillin, and sulphonamides in the early 1900s.8 Since the early 1970s, topical silver sulfadiazine creams (SSD), such as Silvadene® (Monarch Pharmaceuticals, Inc., Bristol, Tennessee), have been used for wound and burn care. Although many patients have experienced improved wound-healing outcomes, the silver creams are not completely free of drawbacks. Silver sulfadiazine actively discharges silver ions as it comes in contact with wound exudate. These ions are quickly neutralized and, thus, require frequent application of the cream to the wound site. The need for recurrent application of the product ultimately adds to cost of care due to the labor-intensive nature. Additionally, there is no mechanism to measure the actual amount of silver ions that reach infected tissue. Despite these drawbacks, this early discovery of silver's ability to help heal wounds spawned many of the advances we have seen in the area of silver-based wound management.

Silver Activity Against "The Enemies"
       Ionic silver is a natural antimicrobial agent and is gaining acceptance as a nontoxic alternative to help keep wound microbes under control. Silver is broad spectrum in its ability to kill aerobic and anaerobic, Gram-positive and Gram-negative bacteria including resistant forms, such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant enterococcus (VRE), as well as fungus and viruses.9,10 It is abundant in nature as well as inexpensive, making it perfect for long-term care use. Silver's antimicrobial action is highly toxic for microorganisms but has relatively low toxicity for human tissue cells, which lends itself well to topical application. The antimicrobial activity is due to the positively charged silver ion: Ag+. Pure silver will not release great amounts of Ag+. Silver compounds (silver plus something else) release various amounts of Ag+.
       Minute amounts of ionic silver, as little as 0.1 parts per billion, are enough to be antimicrobial.8 Silver's mechanism of action includes the disruption of protein in cell membranes resulting in a loss of integrity and inhibition of the function of some bacterial enzymes.11 According to the Environmental Protection Agency (EPA), silver has a minor toxicity classification, similar to barium and magnesium.7 Uncontrolled ingestion of large amounts of silver can cause a toxicity that can be harmful.12 Toxicity, called agyria, deposits silver permanently in the dermal layer of the skin and in the body organs and can be damaging to health.8 Even silver sulfadiazine cream can deliver toxic amounts of silver and delay wound healing. Some experts recommend discontinuing the product if leucopenia develops.
       Antibiotics have frequently been used to rid wounds of bacteria. Silver is more universally effective and broad spectrum than antibiotics due to the way it binds to various structures in bacteria and alters their function.13 It is important to deliver enough silver to the wound to eliminate the topical or surface bacteria without delivering so much that local wound toxicity could occur. Until recently, because of problems with instability, it has been difficult to place ionic silver in a form that is practical for use for wound care.14 Silver dressings can be used for any type of wound where it is desirable to decrease surface bacteria or prevent overgrowth of surface bacteria and/or other microbes. Some silver dressings are indicated for use in infected wounds. Silver dressings may also function as physical or chemical barriers against the entry or exit of bacteria from the wound.15
       Use of ionic silver may decrease surface toxins that are known to delay healing. Unlike antibiotics, there are no pathological bacteria known that have developed a resistance to the effects of ionic silver. Silver dressings are a good choice when it is desirable to free the wound of microbes or to protect the wound from colonization with bacteria. In addition, silver is also recognized for its anti-inflammatory properties.
       Various dressing materials contain and/or release silver into the wound. These wound management dressings are outlined in Table 1. The delivery method of silver should match the needs of the wound. For example, if a wound is heavily draining and deep, a product that absorbs the drainage while filling the dead space should be considered. While using silver-containing dressings, the general principles of prudent wound care and wound bed preparation should be practiced.16 For instance, wounds with devitalized material should be debrided; all wounds in a home care environment should be cleansed with each dressing change and a moist environment should be maintained.
       Ionic silver is only transported to the wound when moisture is present. Wound moisture is usually sufficient to activate silver release. However, some of the silver-containing dressings require the addition of moisture initially and every few hours through the treatment period to release the ions of silver from the metallic silver in the product, which is not exactly cost effective or convenient in an acute care, home care, or long-term care setting. Technological advances have now made ionic silver stable and realistic for wound care. Newer products on the market utilize the latest self-releasing/slow-release silver technology that does not require added moisture, saving caregiver effort, while ensuring uniform delivery of silver over a prolonged period of time. Many of the new silver dressings, moreover, do not require frequent changes, and some can remain on the wound as long as seven days. Consult your product sales representative and review package inserts if unsure of application and wear time.

Contraindications and Side Effects
       Silver has a very low potential for allergy or sensitivity problems. Many patients that have demonstrated an allergy or reaction when using silver sulfadiazine cream actually had a reaction to the sulfa component of the product. Allergies to silver jewelry is fairly common; however, it's not the silver that causes the problems; rather, a high nickel content is much more likely to blame. Today's silver dressings deliver small amounts of silver, so they're not likely to be locally toxic or cause systemic absorption.
       Silver may have poor absorption into necrotic tissue and, thus, not kill bacteria deep within the nonviable tissue. As with the treatment of all wounds, primary or concurrent debridement techniques should be in place while silver dressings are being used, as mentioned earlier. Some silver dressings should be used only with sterile water as a cleansing agent. This is because metallic silver may bind with sodium ions in normal saline solution and thus make the silver unable to have bactericidal action. Manufacturers of enzymatic debriding agents also warn that some silver dressings should not be used while debriding with enzymes. Be sure to read the accompanying literature and package inserts and consult with your manufacturers and distributors for these particulars as well as education and inservicing for your facilities' needs. Silver may cause local or systemic toxicity when used in large amounts. Beware of any permanent staining of the skin, which may indicate local toxicity or agyria. This could alter the ability of cells to proliferate.

A "Shining" Example
       With an increasing focus on early intervention and prevention of wounds and rising demand for better technologies that can heal wounds faster and reduce healing time, silver may provide the answers. Silver dressings have progressed substantially and are now readily available for assistance in healing difficult, infected, and bacteria-laden wounds. Silver continues to be a safe and effective way to provide antimicrobial activity for wounds, allowing for optimal healing. Fear of ineffective control of antibiotic-resistant microbes can be eliminated with the use of these safe new silver dressings.
       The market for advanced wound management technologies is constantly evolving and becoming more highly competitive, making purchasing of these products more attractive to the long-term care provider. This environment is driven by rising demand for efficient, cost-effective dressings to address the needs of the chronic wound care patient. Look forward to seeing more advanced healing silver dressing on the horizon. With understanding of how they work, silver dressings are a great option for management of many chronic and acute wounds. Make your wound care protocol a "shining" example by including ionic silver dressings in your plan of care. Never forget the "Silver Rule!"