(LR-053) Combination Negative Pressure Wound Therapy with Supplemental Oxygen Decreases Bioburden in Translational Porcine Pilot Study
Thursday, May 16, 2024
7:30 PM – 8:30 PM East Coast USA Time
Lawrence Lavery, DPM, MPH – Plastic Surgery – University of Texas Southwestern Medical Center; Ariane Lazzarini, B.S. – Plastic Surgery – University of Texas Southwestern Medical Center
Introduction: Negative pressure wound therapy (NPWT) is a vital tool in the management of wounds, improving wound closure and time to wound closure. Topical oxygen therapy has been demonstratedto promote wound healing.The aim of this pilot study was toevaluate the effect of a novel device combining NPWT with adjunctive O2(NPWT-O2) vs.intermittent NPWT on bioburden in infected porcine wounds.
Methods: Two5-cm diameter full thickness wounds were created on the dorsal paravertebral surface of 4 pigs.All animals were singly housed in the same room with 12-hour light and dark cycles. They were fed chow ad libitum and fasted for 12 hours prior to anesthesia events. Bioburden investigation was performed on one pig. The animal was wounded and immediately inoculated with 1x10^6 CFU/mLStaphylococcus aureus(ATCC-35556) under occlusion for 3 days. Wounds were debrided and application of NPWT-O2 and intermittent NPWT commenced – “Day 0”. Swab specimens were collected post-debridement on days 0, 7, 14, and 21. They were placed in a -80°C freezer within 60 minutes of collection and sent to RTL Genomics (Lubbock, TX) for 16s rRNA analysis after the trial. Punch biopsies from the leading edge of the wound were collected and analyzed by a veterinary histopathologist using hematoxylin and eosin, trichrome for organization of collagen, and factor VII for microvessel density. Outcomes included changes in bioburden, wound area and volume, and histology.
Results: On day 0, wounds A and B had 1.78x10^7 and 3.50 x 10^7 16s copies per swab, respectively. On day 7, wound B with NPWT-O2 showed a 2-log reduction while wound A with intermittent NWPT maintained the same bioburden, which continued until day 14. Both wounds had a 50% wound area reduction by day 7 and a 90% reduction by day 28. Histological changes revealed increased trichrome staining at the end of therapy across all wounds.
Discussion: NPWT-O2 resulted in a similar wound area reduction and a clinically significant decrease in bioburden when compared with intermittent NPWT alone in a porcine translational model. Further study on a larger scale is warranted for human application.