Next Generation Systems to Delivery Combination Negative and Positive Pressure Wound Therapy with Instillation of Oxygen Into the Wound Bed. Pre-clinical Information from in Vivo Models
The benefits and limitations of negative pressure wound therapy (NPWT) with and without instillation of fluids have been reported in the literature, with little to no innovation in delivery over the last decade.
Hyperbaric oxygen therapy (HBOT) has shown benefit in a variety of wound classifications yet is limited by cost, availability and contraindications.
Two novel NPWT systems will be presented. First, a FDA approved system with pathogen-binding-acetate-mesh wound filler and pure hypochlorous acid delivery will be described.
Next, preclinical in vivo data of a combination negative and positive pressure wound therapy system with gas instillation (NPWT-PPWTi) capability, will demonstrate diffusion of oxygen into the deep periwound tissues.
Ten, 70 kg landrace pigs with 6x6x3cm deep back wounds were utilized. Pathogen-binding-acetate-mesh was used as the wound filler. Drainage tubes for oxygen delivery and wound drainage were inserted into the wound. An Integra™ Licox® Brain Tissue Oxygen Monitoring probe was inserted into the periwound tissue to monitor oxygen tension, with Oxford Optronix® fluorescence continuous imaging to monitor and compare tissue perfusion.
Oxygen tension increased by 300 mmHg after 15 minutes of exposure at 0.1cm and 100 mmHg at 0.2cm of tissue depth. Oxygen diffuses into the tissues during therapy yet the level of NPWT/PPWT did not effect diffusion rate in this study. Oxygen tension reaches a maximum after 8-10 minutes of exposure.
Commercialization of a NPWT-PPWTi system may enhance local delivery of oxygen to the deep tissues of poorly perfused wounds without the risks of HBOT.