Background: Closed incision Negative Pressure Wound Therapy (iNPWT) can reduce surgical site complications, but cost effectiveness is limited by the expense of electromechanical NPWT systems. This report describes a 30-patient first-in-human clinical study of a novel device: negative pressure Surgical Incision Management System npSIMS (Aatru Medical LLC, Ohio, USA) that utilises a solid-state chemical reaction to provide negative pressure of between -110 - 60 mmHg and promises to be significantly less costly to manufacture and implement than electromechanical systems.
Methods: The study was approved by New Zealand HDEC ref20/STH/144 and registered at clinicaltrials.gov (NCT04488666). Following a pause in recruitment due SARS-CoV-2 in New Zealand, an interim analysis is presented after 16 participants. The primary endpoint is the longevity of negative pressure to the wound over 7 days. Wound healing and complications were assessed at day 7, day 14 and day 30.
Results: The first 16 patients in the study (mean age 69.6±9.6; mean BMI 29.0±3.8 kg m-2) had a mean wound length of 7.5±2.5 cm following elective plastic surgical and spinal surgery. The npSIMS maintained negative pressure for a mean of 6.06 ± 1.61 days per incision. The mean number of npSIMS devices per incision was 1.19 ± 0.54. Assessment scores indicated overall normal wound healing and scar quality.
Discussion: Participant and clinician assessments showed that the devices were easy to use and totally silent in operation. In spinal surgery patients, where increased shear forces placed a greater strain on the dressing, two device failures prompted an enhanced design to improve adhesion of the port to the dressing. The enhanced npSIMS will be employed on resumption of the study.
Conclusion: A novel, non-electrical NPWT device has performed safely and effectively in initial analysis, was well tolerated and shown to be convenient and easy to use. Additional patient recruitment is planned.