Silver compounds have widely been used as wound antiseptics, mainly in burns. Silver sulfadiazine (SSD) and silver nitrate (AgNO3) are among the most commonly used. Silver sulfadiazine is the most broadly used treatment for the prevention of infection in patients with burn wounds.[95,96] Combinations of SSD with cerium nitrate and nanocrystalline silver releasing systems (Acticoat®, Westaim Biomedical, Exeter, New Hanover) have been developed in order to increase its efficacy and/or reduce its toxicity. Newer silver formulations appear to increase the rate and degree of microbial killing, decrease exudate formation, and can remain active for days.
Animal studies examining the effects of SSD and AgNO3 on wounds have showed no significant effect on epithelization rate ( Table 6 ). SSD was also found to increase the rate of neovascularization. In another study in rats, silver compounds were found to promote wound healing, reduce the inflammatory and granulation phases of healing, and influence metal ion binding. Moreover, Geronemus, et al., found increased reepithelization rate in domestic pigs with the use of SSD.
Yet, Leitch, et al., found SSD to cause inhibition of wound contraction in an acute wound rat model. Likewise, Niedner, et al., found a slight, nonsignificant reduction of granulation tissue formation with the use of AgNO3.
Among human studies, the authors present only those on patients suffering from wounds other than burns, as there is currently no controversy for the use of silver compounds on burn patients, as mentioned above. Kucan, et al., examined the effects of SSD on bacterial counts in patients with infected chronic pressure ulcers. He found SSD to be effective in decreasing the bacteria below 105/gr tissue in all the ulcers treated. In a randomized trial with venous ulcers, SSD one-percent cream was proved to statistically reduce the ulcer size compared to the placebo, while in another study it was found to be well tolerated and effective on wound cleansing and granulation tissue formation. Livingstone, et al., studied the effect of AgNO3 and an antibiotic solution (neomycin plus bacitracin) on reducing autogenous skin graft loss due to infection in patients with thermal injury. They found both medications to be effective in comparison to the control group (Ringer’s lactate solution), but the antibiotic solution was associated with the rapid emergence of drug-resistant organisms, while AgNO3 was not. Nanocrystalline silver compounds have been found to increase the reepithelization rate of meshed autografts and appear to be promising for the treatment of other chronic wounds as well. The anti-inflammatory effects of silver could be associated with the vehicle, which reduces wound drying, reducing therefore inflammation (moist wounds have been found to be significantly less likely to be infected). More clinical trials are needed for the evaluation of nanocrystalline silver.
Summarizing, it appears that silver compounds do not have a negative effect on wounds and maybe accelerate wound healing clinically. Their in-vivo antimicrobial activity is not in question.
Wounds. 2003;15(5) © 2003 Health Management Publications, Inc.
Cite this: Antiseptics on Wounds: An Area of Controversy - Medscape - May 01, 2003.