Sharon Lindsay, Alexander Waite, Rachael McInnes, Breda Cullen, Systagenix, Gargrave, UK Robert J. Snyder, DPM, MSc, CWS, Professor, Barry University SPM, Miami Shores, Florida, USA

1. Abstract
Silver Release in Vitro
Bactericidal Activity
Clinical Data
Conclusion
An in vitro and clinical assessment of a non‐
adherent, antimicrobial wound dressing
against a broad spectrum of bacteria
Sharon Lindsay, Alexander Waite, Rachael McInnes, Breda Cullen, Systagenix, Gargrave, UK
Robert J. Snyder, DPM, MSc, CWS, Professor, Barry University SPM, Miami Shores, Florida, USA
EP451
EWMA May 2013
C1385‐2

2. Abstract
evaluate the antimicrobial efficacy of a non adherent silver hydro‐alginate wound
essing, against a broad spectrum of bacteria. This was conducted using a range of
inically relevant and predominant microbes including antibiotic resistant strains.
nalysis of the antimicrobial activity of the dressing was conducted in vitro using a
mbination of log10 reduction testing and swab analysis (swabs taken from directly
erneath dressing samples incubated on inoculated agar plates). In addition in vitro
sessment of silver release was conducted to give an indication of longevity of the
microbial activity. This data is coupled with case reports detailing the treatment of
infected chronic wounds, with focus on both efficacy and ease of use.
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3. Abstract (continued)
in vitro analysis of the non‐adherent silver dressing indicates antimicrobial activity
gainst the full range of clinically relevant microbes tested. This includes ≥4 log10
uction within 1‐3 hours and swab analysis that indicates bactericidal activity against
the antibiotic resistant strains tested. Assessment of silver release indicates the
timicrobial effect to be sustained over a period of 7 days. In addition, case studies
onstrate clinical efficacy against infected wounds. Case reports also show ease of use
to the non‐adherent layer including reduced fibre shed and reduced discomfort on
removal.
his non adherent silver hydro‐alginate wound dressing has been shown to have a
stained broad spectrum antimicrobial activity making it effective against clinically
nt microbial strains including resistant strains. In addition the dressing was found to
be easy to remove and have reduced wound disruption upon removal.
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4. Silver Release in Vitro
er hydro‐alginate and Silver hydro‐alginate non‐adherent released consistent levels
lver (17‐20ppm) over a 7 day period.
odology
ver hydro‐ alginate wound dressing and its non‐adherent equivalent were each
bated in a simulated wound fluid (SWF).
F was changed every 24hrs & silver levels analysed in the removed fluid.
er Release into SWF was measured at 24 hour intervals using atomic absorption.
Dressing trade names: Silver
hydro‐alginate dressing =
SILVERCEL®, Non‐adherent Silver
hydro‐alginate dressing =
SILVERCEL® NON‐ADHERENT
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5. 013
Bactericidal Activity of a Non‐Adherent
Silver Hydro‐Alginate Dressing in Vitro
Swab Analysis
actericidal action on a range of bacterial strains including antibiotic resistant strains.
hodology
t dressings were placed onto agar plates inoculated with bacterial strains.
owing an incubation period swabs were taken from directly underneath the dressing.
ulting swabs were streaked onto fresh agar plates to identify viable microbes.
Scoring of Bacterial Growth:
‐No growth
+ Light growth
++ Moderate growth
+++ Heavy growth

6. Bactericidal Activity of a Non‐Adherent
Silver Hydro‐Alginate Dressing in Vitro
Log10 Reduction Assay
tericidal action on a range
bacterial strains including
ibiotic resistant strains.
dology
dressings were placed into a
tified bacterial suspension.
rial suspensions were
led at frequent time points
the duration of testing.
ction in viable bacterial
er was noted at each time
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7. Clinical Data
of 10 case reports involving the use of a non‐adherent silver hydro‐alginate wound dressing in the
nt of different infected wound scenarios. Patients were treated for a minimum of 4 weeks, with the
to continue treatment with a silver dressing based on continual assessment.
Summary
port Wound Type
Infection Pain on dressing removal
wk 1 wk 2 wk 3 wk 4 wk 1 wk 2 wk 3 wk 4
1 VLU ↓ ↓ ↓ ↓ 5 4 3 1
2 VLU ↓ ↓ None None 8 9 3 2
3 VLU ↓ ↓ ↓ ↓ 1 1 1 1
4 VLU ↓ ↓ ↓ ↓ 1 None None None
5 DFU ↓ ↓ ↓ None 1 1 2 1
6 DFU ↓ ↓ ↓ ↓ 1 1 1 1
7 DFU ↓ ↓ ↓ ↓ 1 3 1 1
8 DFU ↓ ↓ ↓ ↓ 4 1 1 1
9 DFU ↓ ↓ ↓ ↓ 1 1 1 1
10 Surgical ↓ ↓ None None 1 2 2 2
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8. Clinical Data (continued)
Example Case Reports – Patient 1
Baseline
Week 2
Week 4
old woman with a venous leg ulcer. The
d appeared heavily colonised but uninfected
ocalised erythema, exudate and pain.
1: Signs of local infection were reduced; no
dour, less exudate and erythema. Wound bed
ed evidence of 25‐50% granulation tissue.
2: Pain at dressing change was reduced.
al signs of infection were minimal. Wound bed
yed 50‐75% granulation tissue.
s 3–4: Further reductions in pain, exudate
erythema . At the final assessment there was
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9. Clinical Data (continued)
old woman with type 1 diabetes presenting
neuropathic foot ulcer of 24 months
on on the right plantar mid‐foot.
1: Reduced signs of local infection, no
dour, light exudate levels and evidence of 50‐
ranulation of the wound bed. Patient did not
ence pain during dressing changes.
2‐4: Continued reduction in the signs of local
on, no malodour, light exudate levels and
nce of 50‐75% granulation tissue.
Baseline
Week 2
Week 4
Example Case Reports – Patient 9
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10. Conclusion
non‐adherent silver hydro‐alginate wound dressing tested demonstrated consistent
ls of silver release in vitro over a period of 7 days.
eover this was shown to be bactericidal against a range of key bacterial strains
ciated with chronic wound infections, including antibiotic resistant strains.
ries of case reports detailing the use of this product in the treatment of different
nd scenarios has demonstrated:
a.) Efficacy in the reduction of wound infection.
b.) Reduced pain on dressing removal.
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