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Notes: In persons with venous ulcers and an absence of arterial disease, high compression as exemplified by the four layer bandage (Profore) has been demonstrated to be effective by a meta-analysis of existing studies. Despite optimized compression, some venous ulcers do not heal at the expected rate and persistent inflammation or infection may delay or prevent healing. We report the results of a case series that demonstrates an ionized silver dressing with prolonged release of nanocrystalline crystals (Acticoat 7) can decrease bacterial burden and accelerate healing in venous ulcers not healing at the expected rate. Patients with venous ulcers were treated with a prolonged release absorptive nanocrystalline silver dressing (Acticoat 7) under a four layer bandage (Profore) for 12 weeks, or until healing. The primary efficacy objective measured the effect of the silver dressing on the wound microflora. Biopsies of the wounds were taken at baseline and after treatment with the silver dressing (Acticoat 7) and were analyzed for the bacterial species and number of bacteria present. In addition, serum silver levels were assessed at baseline, weeks 4, 8 and week 12 or final assessment. A total of 15 patients (9 male, and 6 female) were enrolled into the study. The median age was 63 years (range 30–83 years). The median duration of current ulceration was 17.3 weeks (range 4 weeks to 11 years) and the median ulcer area was 4.8 cm2(range 1.8–43.9 cm2). The median exposure to Acticoat 7 was 82 days (range 8–86 days). There was a statistically significant reduction (p = 0.0114) in the log10(total bacterial count) between the baseline and final biopsies (median 4.48 and 3.00, respectively). Four patients healed, 8 patients continued to the end of the 12-week study period and three patients were discontinued early. Of those patients who did not heal, 4 had more than a 94% reduction in wound area by the end of the 12-week study period. For all patients, the median percentage reduction in ulcer area was 94.4% and the median final ulcer area was 0.4 cm2. Statistical analysis showed a significant increase (p = 0.054) in serum silver concentration during the treatment period. At baseline, prior to the silver dressing treatment (Acticoat 7), the median silver concentration was 0.3 μg/L (range: 0.20–1.90 μg/L). The median within patient change from baseline serum silver concentration was an increase of 0.15 μg/L (range: −0.3–2.8 μg/L). Although this small increase was observed it was not considered clinically significant. This study illustrates the use of prolonged release nanocrystalline silver dressing to decrease the bacterial burden of chronic venous ulcers not healing at the expected rate.

Notes: Often chronic wounds have an increased bacterial burden that can impair healing without the classical clinical signs of infection. Silver dressings may provide an alternative topical method to control bacterial burden.The primary aim of this study was to evaluate the effect of 2–4 weeks therapy with the Silver Containing Hydrofiber® dressing on quantitative bacterial burden and clinical improvement in chronic wounds not healing at the expected rate.This was a single centre, four-armed study which included a total of 30 patients with diabetic foot ulcers, leg ulcers, pressure ulcers and miscellaneous wounds that did not fit into any of the above categories. Patients had a baseline quantitative bacterial biopsy and this was repeated at weeks 2 to 4. The wound size was recorded along with a semi quantitative estimate of exudate and the periwound temperatures. Repeat measurements were performed at the follow-up visits and the decrease in wound size calculated. The underlying cause of the ulceration was be treated and corrected. This was followed by application of silver containing hydrofiber® dressing. There was a significant delay in healing of the leg ulcers associated with increased bacterial burden in the quantitative biopsy bacterial burden results at week 0 and healing at week 2. (p = 0.01). Other subgroups had a similar association that did not reach statistical significance. The presence of an increased exudate in the leg ulcers at week two was associated with delayed healing at week 4 (p = 0.05). There was also a significant increase in skin surface temperature of the surrounding skin with an increased quantitative bacterial biopsy of the deep wound compartment for venous, diabetic neurotrophic foot ulcers and pressure ulcers with p values of 0.05, 0.01 and 0.01 respectively. There was no significant decrease in exudate or increased healing of the wounds with the application of the silver hydrofiber dressing in this difficult to heal population. The population studied in this case series had increased bacterial burden in the deep compartment as measured with increased exudate and or an increased temperature of the periwound skin. These patients have an increased bacterial burden in the deep wound compartment that does not respond to topical ionized silver in the dressing studied.

Notes: The treatment of venous ulcers must start with compression and if the ankle brachial index is greater than 0.8 high compression bandages can be applied. Despite edema control, there are a number of venous ulcers that do not heal at the expected rate. Patients with venous ulcers of greater than 4 weeks duration were treated with a prolonged release absorptive nanocrystalline silver dressing (Acticoat 7) under the 4 layer bandage, Profore for 12 weeks, or until healing. Biopsies were obtained from the ulcer base at week 0 for histology and bacterial burden. Duplicate biopsies for quantitative bacteriology were performed with one submitted whole and the second bisected into superficial and deep components. The paired biopsies were then repeated after a median of 6.5 weeks (range 2 to 12 weeks). The histological specimens were examined by the histopathologist (SR). Inflammatory infiltrates were identified in the superficial, middle and deep segments of the biopsies. Acute infiltrates were identified through the concentration of neutrophils and chronic infiltrates by the presence of lymphocytes. Each biopsy and each segment was graded for infiltrates on a four point semi quantitative score. A total of 15 patients (9 male, and 6 female) were enrolled into the study. The median age was 63 years (range 30–83 years). The median duration of current ulceration was 17.3 weeks (range 4 weeks to 11 years) and the median ulcer area was 4.8 cm2(range 1.8–43.9 cm2). The median exposure to Acticoat 7 was 82 days (range 8–86 days).There were 12 sets of paired biopsies that were analyzed. There was a statistically significant reduction (p = 0.0114) in the log10(total bacterial count) between the baseline and final biopsies (median 4.48 and 3.00, respectively). Four patients healed, 8 patients continued to the end of the 12-week study period and three patients were discontinued early. For all patients, the median percentage reduction in ulcer area was 94.4% and the median final ulcer area was 0.4 cm2. Analysis of the histology and bacteriology data demonstrated that the presence of a high neutrophilic infiltrate in skin biopsies was associated with high bacterial counts (superficial compartment of the quantitative biopsies) at week 4 and delayed healing (p = 0.037). In the week 0 biopsy, increased lymphocytic infiltrates within the superficial and middle segments were associated with accelerated healing in the first 4 weeks (p = 0.26 and 0.09). The nanocrystalline silver dressing has demonstrated an anti-bacterial and permissive but selective anti-inflammatory action allowing lymphocytic infiltrates to increase associated with an accelerated reduction in ulcer size.