Slough Absorbency and Antimicrobial Efficacy of a Non-Woven PHMB Dressing

Rachel Burns and Cerys Griffiths share the findings from a recent poster that was presented at the 2023 SAWC Fall conference in Las Vegas, Nevada.

Transcript:

Rachel Burns:

Hello and welcome to our poster presentation on Investigating Both the Antimicrobial Efficacy of a Non-Woven PHMB Dressing and the Ability of the Dressing to Absorb Wound Slough. Presented today by myself, Rachel Burns, Clinical Project Manager...

Cerys Griffiths:

And by Cerys Griffiths, R&D Scientist and the lead author of the poster.

Rachel Burns:

A large majority of chronic wounds [have] sloughy tissue, which can make it difficult for clinicians to accurately assess the wound bed. It contributes to delayed healing preventing the wound from continuing through the normal wound healing process. Slough prolongs the inflammatory phase, increases odor and exudate, provides a focus for bacteria, hides and elevates the risk of infection. Developing an infection not only affects wound healing, it has an associated impact on the person and their quality of life. It can also increase management time for the clinicians alongside potential practical and financial implications.

The appropriate and safe removal of slough and infection are an essential elements of wound healing. A common chronic wound type is a venous leg ulcer. These wounds are complex and the person with a wound may have several comorbidities. Advanced wound care dressings are frequently used with compression therapy as part of the treatment plan for both the person with a wound and the clinician. Selecting a dressing that can effectively address desloughing, infection and exudate management that can be used under compression is key to promote wound healing.

Advanced Medical Solutions, AMS, have designed and developed a unique, highly absorbing, gelling fiber dressing composed of carboxymethylcellulose--CMC fibers--and antimicrobial polyhexamethylene biguanide--PHMB--that can address these critical factors. The following poster presentation investigates this further.

Cerys Griffiths:

There were two parts to this in vitro investigation. The first looking into the CMC PHMB's ability to absorb thick and viscous exudate solutions. Slough absorption was performed in line with an industry standard to assess the absorbency properties of wound dressings. We modified the viscosity using a thickening agent to assess the dressing's ability to pick up different types of wound exudate. We measured the absorption and retention properties of this thick and viscous solution against our CMC PHMB product and other non-woven competitive products already on the market.

It is also important to consider the antimicrobial efficacy of the dressing whilst it is under compression. Here, we assessed the dressing under ATCC guidelines and applied a weight to simulate compression bandaging. Dressings were analyzed over a clinically relevant time point of 7 days to confirm whether the antimicrobial activity of the device remains effective whilst it is under this simulated compression.

The results for slough absorption show that the CMC PHMB gelling fiber is highly effective at absorbing various viscosities of simulated wound fluid. Grams per 100 cm² is a measure of the amount of solution absorbed per a 10 by 10 cm sample. Our dressing managed to absorb 33 grams per 100 cm², and we absorbed 33% more and retained 29% more than the market leader, Dressing B. It also outperformed all other products tested, which is a promising sign of the product's ability to remove sloth.

The results from the antimicrobial compression testing show that the dressing remains antimicrobial effective whilst it is under simulated compression. All microorganisms tested achieved total eradication within 7 days. There was consistent performance across a range of species, including gram-positive and negative bacteria, a yeast and a mold, showing that the antimicrobial performance has not been affected by the addition of the compression element.

To conclude the in vitro data, Advanced Medical Solutions, CMC PHMB gelling fiber dressing absorbed a greater percentage of the solution than any other product tested, including the market leader, Dressing B, where we managed to absorb 33% more. The highest amount of slough retained was achieved by our CMC PHMB product retaining 28 grams per 100 cm². Additionally, the antimicrobial efficacy at the CMC PHMB gelling fiber remained effective whilst the dressing was under simulated compression.

Rachel Burns:

The Advanced Medical Solution CMC PHMB dressing have shown in vitro potential clinical benefits, the ability to handle larger amounts and different types of exudate, retain wound fluid within the dressing, maintain antimicrobial efficacy, especially whilst under compression. This dressing could have a positive effect on wounds requiring compression therapy such as venous leg ulcers, as well as other chronic wounds impacting the wound progression and wound healing.

Cerys Griffiths:

Thank you for listening. For any further information on AMS or PHMB, please scan the QR codes on the screen. And as a final note, CMC PHMB gelling fiber is cleared by the FDA.