Abstract
Introduction: S epidermidis is a recognised major biofilm pathogen and has been implicated in medical device contamination ranging from artificial hip prostheses to breast implants. Pseudomonas aeruginosa is a known pathogen in chronic wounds. Within biofilms, bacteria are enclosed in a polymeric matrix or EPS which cements the bacteria to each other and to the surface. Biofilms act to protect the bacteria from the environment increasing resistance to host immunity, antibiotics and biocides. More recently, we have shown that biofilm occurs on the surface of chronic wounds and that this may have aetiological implications.
Method: Staph spp and pseudomonas spp biofilm were grown on glass coupons using the CDC biofilm reactor for 48 hrs and the coupons randomly inserted into the wound model and for 24 hrs subjected to:
1. No instillation plus TNP
2. 0.1% w/v formulated hypocholorous acid instillation plus TNP
3. Saline instillation (no biocide) plus TNP
4. Betadine instillation plus TNP
Betadine and saline instillations were for 30 minutes every 8, 4 and 2 hours per day in separate experiments. NVC instillation was for 3 minutes, every 8, 4 and 2 hours per day in separate experiments. Following treatment, the coupons were carefully extracted to avoid damaging the biofilms. The effect of TNP on the biofilms was then assessed by colony forming units and electron microscopy.
Results: The results show that lower frequency of instillation did not have significant effect on bacterial load for both types of bacteria. Increase in frequency of instillations resulted in no growth of pseudomonas while increase in frequency of instillations resulted in a significant decrease in staph spp.
Method: Staph spp and pseudomonas spp biofilm were grown on glass coupons using the CDC biofilm reactor for 48 hrs and the coupons randomly inserted into the wound model and for 24 hrs subjected to:
1. No instillation plus TNP
2. 0.1% w/v formulated hypocholorous acid instillation plus TNP
3. Saline instillation (no biocide) plus TNP
4. Betadine instillation plus TNP
Betadine and saline instillations were for 30 minutes every 8, 4 and 2 hours per day in separate experiments. NVC instillation was for 3 minutes, every 8, 4 and 2 hours per day in separate experiments. Following treatment, the coupons were carefully extracted to avoid damaging the biofilms. The effect of TNP on the biofilms was then assessed by colony forming units and electron microscopy.
Results: The results show that lower frequency of instillation did not have significant effect on bacterial load for both types of bacteria. Increase in frequency of instillations resulted in no growth of pseudomonas while increase in frequency of instillations resulted in a significant decrease in staph spp.
Original language | English |
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Article number | PR52P |
Pages (from-to) | A64-A65 |
Number of pages | 2 |
Journal | ANZ Journal of Surgery |
Volume | 79 |
Issue number | s1 |
DOIs | |
Publication status | Published - May 2009 |
Externally published | Yes |
Event | Royal Australasian College of Surgeons Annual Scientific Congress - Brisbane, Australia Duration: 6 May 2009 → 9 May 2009 |