Abstract:

Background
Silver-containing treatments are popular and used in wound treatments to combat a broad spectrum of pathogens, but evidence of their effectiveness in preventing wound infection or promoting healing is lacking.

Objectives
To establish the effects of silver-containing wound dressings and topical agents in preventing wound infection and healing of wounds.

Search strategy
We searched the Cochrane Wounds Group Specialised Register (6 May 2009); The Cochrane Central Register of Controlled Trials (CENTRAL) (2009 Issue 2); Ovid MEDLINE (1950 to April Week 4 2009); Ovid EMBASE (1980 to 2009 Week 18); EBSCO CINAHL (1982 to April Week 4 2009) and Digital Dissertations (to May 2009) for relevant trials. We contacted manufacturers and distributors.

Selection criteria
Randomised controlled trials (RCTs) comparing silver-containing wound dressings and topical agents with silver-containing and non silver-containing comparators on uninfected wounds.

Data collection and analysis
Two authors independently selected trials, assessed risk of bias, and extracted data.

Main results
We identified 26 RCTs (2066 patients). Heterogeneity of treatments and outcomes precluded meta-analysis. We grouped results according to wound type, and silver preparation.

Burns

Thirteen trials compared topical silver (in a variety of formulations - including silver sulphadiazine (SSD) cream) with non-silver dressings. One trial showed fewer infections with silver nitrate when compared with a non-silver dressing, but three trials showed significantly more infection with SSD than with the non-silver dressing.

Six trials compared SSD cream with silver-containing dressings. One showed significantly fewer infections with the silver-containing dressing (Hydron AgSD) compared with SSD, the remaining five found no evidence of a difference.

One trial compared two silver-containing dressings, and showed a significantly lower infection rate with silver-coated gauze (Acticoat®) than with silver nitrate gauze.

Other wounds

Six trials compared SSD/silver-containing dressings with non-silver dressings (nine dressings in total). Most comparisons (seven) found no significant differences in infection rates; one trial in a variety of wounds exhibited significantly fewer infections with SSD/hydrocolloid, but another, in acute wounds, found significantly more infections with SSD. Only one comparison showed a significant reduction in healing time associated with a silver-containing hydrofibre dressing in diabetic foot ulcers.

Authors' conclusions
There is insufficient evidence to establish whether silver-containing dressings or topical agents promote wound healing or prevent wound infection; some poor quality evidence for SSD suggests the opposite.