In vitro evaluation of a hybrid negative pressure system for wound therapy

Objective The objective of this study was to assess whether negative pressure could be maintained accurately and repeatably with a wall‐suction‐based hybrid negative pressure wound therapy (h‐NPWT) system by comparing it with a commercial negative pressure wound therapy (NPWT) device. Study design In vitro experimental study. Methods A commercial NPWT device (control) and three h‐NPWT devices, with 0, 3, and 6 meters of additional tubing using the hospital‐wall suction (groups 1, 2, and 3 respectively), were applied sequentially to a commercial NPWT dressing on a silicone skin substrate and set to run at a continuous pressure of −125 mmHg. The pressure within the wound space was monitored at 10 second intervals for 24 h. The process was repeated five times for each group. Results The commercial NPWT device produced an average pressure variance of 3.02 mmHg, and the h‐NPWT produced average variances of 4.38, 4.24 and 4.20 mmHg for groups 1, 2 and 3, respectively. All groups produced an average pressure within 0.15 mmHg of −125 mmHg over the 24‐hour period, and the h‐NPWT systems produced the smallest range with all values remaining within a ±5% variation from −125 mmHg. Conclusion The h‐NPWT system achieved negative pressures that were comparable to those of a commercial control NPWT device. The addition of tubing between the skin substrate and the canister did not affect the pressure applied at the wound site. Clinical significance The h‐NPWT device tested in this study can be considered as an alternative for negative wound therapy when a commercial device cannot be used.