An Assessment of Fluid Penetration Through a New Fenestrated Collagen Wound Dressing

Adequately managing exudate is critical to effective wound care. Collagen wound dressings are often used in chronic wounds due to their ability to sequester matrix metalloproteinases (MMPs) via a sacrificial substrate effect. When applied to rapidly exuding wounds, the ability of collagen dressings to allow quick penetration of fluid may be enhanced via the addition of fenestrations.

The objective of this study was to compare the performance of a collagen wound dressing under conditions that are relevant for the application with negative pressure wound therapy (NPWT).The dressings that have been compared are a fenestrated collagen dressing with the non-fenestrated version of the same dressing, as well as a silver-containing version of both the fenestrated and non-fenestrated versions. Testing should answer the question if fenestration enables wound exudate to penetrate.

Samples of product have been put on a sample carrier that was connected with a pump. A suction pressure of 167 mbar/125 mmHg was applied and a simulated wound fluid (SWF, 0.6% aqueous sodium carboxymethylcellulose solution) with a viscosity of 60 mPa was added on top. Penetration time of a certain amount of SWF was measured.

The fenestrated dressings showed a faster penetration time than the non-fenestrated dressings. Penetration through fenestrated samples took 6–36 seconds, compared to 202–313 seconds for non-fenestrated products.

In order to exclude that absorption performance of the two product versions is different in general, a validated in-house method, the so-called “handling test,” has been performed. The method determines the time until the entire product is fully soaked by 0.9% saline. This test revealed that the absorption performance of the fenestrated products is equivalent to the non-fenestrated products.

We conclude that fenestration of the collagen dressings enables wound exudate to penetrate under conditions that are applied for NPWT.