A New Multilayer Wound Dressing That Transports Toxic Matrix Metalloproteases (MMPs) from Chronic Wound Fluid Away from the Wound

Objective: The aim of this case series was twofold: 1) To study the absorptive profile of a new multilayer wound dressing (MBF)* designed to spread wound fluid away from the wound; and 2) To evaluate how treatment with MBF affects the balance of proteases in venous leg ulcers (VLU) as they heal.

Material and Methods: This was a pilot evaluation involving 10 venous leg ulcer patients treated with MBF and standard compression therapy. All patients had adequate arterial circulation (ABI >0.75) and no signs of infection, and all VLUs were <25cm². Follow-up visits were weekly for wound measurement and clinical evaluation. Wound fluid was obtained at baseline (Day 0 prior to initial treatment), and once weekly (from the wound and the wound dressing) for four weeks. Homogenates were analyzed using a custom multiplex kit for MMP-9.

Results: After treatment with MBF, mean MMP-9 levels decreased 46% in two weeks (p=0.042) and 79% in four weeks (p=0.029). Significant levels of MMP-9 were also detected in the spreading layer and retention layer of MBF. Further analysis of MBF revealed transport of MMP-9 distally (up to 4 cm) away from the wound.

Conclusions: MBF effectively transports chronic VLU exudate away from the wound and into the distal spreading and retention layers with minimal swelling. MBF also draws the chronic exudate distally and away from the wound and wound margins. Compression therapy alters the absorption of  *Mepilex Border Flex, Molnlycke Health Care, Gothenburg, SE