Clinical evaluation of a novel, single-use non-electrical incisional Negative Pressure Wound Therapy (NPWT) system based on solid-state oxygen reduction technology.

Introduction: Incisional Negative Pressure Wound Therapy (iNPWT) is emerging as an extremely useful tool for the prevention of complications in closed surgical incisions. Meta-analyses of multiple randomised studies show that applying NPWT to the closed incision can reliably reduce the frequency of surgical site infection (SSI) or surgical site complications (SSC) by around 40%.1 2 However, the cost of electromechanical NPWT devices may limit the uptake of iNPWT, particularly in developing economies. The aim of this study was to evaluate for the first time in patients a novel FDA-approved single-use iNPWT system that offers lower costs and is simpler to manufacture. † Method: The new system utilizes a solid-state chemical reaction to partially reduce the level of oxygen within a rigid vacuum chamber connected to an adhesive dressing with an innovative silicone gasket seal. Oxygen represents 21% of atmospheric pressure (760 mmHg). Reduction of O2 creates negative pressure which is applied to the wound. Pre-clinical studies of the new device show an initial pressure of -105 mmHg is generated which reduces to -60 mmHg after 7 days. Wound healing is normal. A planned-interim analysis is presented after recruitment of 5 participants to a 30 patient first-in-human clinical open label study (NCT04488666). The primary endpoint is the longevity of the delivery of negative pressure to the wound over 7 days. Follow up was for 30 days. Results: The first 5 patients in the study (mean age 69.2; mean BMI 26.0) had a mean wound length of 6.3 cm following elective plastic surgical procedures. All 5 patients were discharged with a single iNPWT device that maintained negative pressure and managed wound exudate for a total of 7 days. There were no adverse events. Participant and clinician assessments showed that the devices were easy to use and totally silent in operation. Discussion: The novel device performed as anticipated in clinical use. A further 25 patients will be recruited including spinal and cardiothoracic incisions. This simple, disruptive, low-cost device, which contains no electrical or magnetic components, provides new options to reduce complications in surgical wounds.