Distribution assessment comparing continuous and periodic wound instillation in conjunction with negative pressure wound therapy using an agar‐based model

Abstract

Negative pressure wound therapy (NPWT) is a widely accepted and effective treatment for various wound types, including complex wounds. Negative pressure with instillation was initially used as a gravity-fed system whereby reticulated, open-cell foam in the wound bed was periodically exposed to cycles of soaking with instillation solution followed by NPWT. Recent publications have alluded to positive outcomes with continuous instillation, where fluid is delivered simultaneously with negative pressure. To evaluate the distribution of instillation solutions to wound beds in conjunction with negative pressure, agar-based models were developed and exposed to coloured instillation solutions to identify exposure intensity via agar staining. This model allowed comparison of continuous- versus periodic-instillation therapy with negative pressure. Continuous instillation at a rate of 30 cc/hour with negative pressure showed isolated exposure of instillation fluid to wound beds in agar wound models with and without undermining and tunnelling. In contrast, periodic instillation illustrated uniform exposure of the additive to the entire wound bed including undermined and tunnel areas, with increased staining with each instillation cycle. These findings suggest that periodic instillation facilitates more uniform exposure throughout the wound, including tunnels and undermining, to instillation solutions, thereby providing therapy consistent with the clinician-ordered treatment.

Comparison of tissue damage, cleansing and cross‐contamination potential during wound cleansing via two methods: lavage and negative pressure wound therapy with instillation

“…For instance, in 2008, Gabriel et al stated that, in their experience, NPWTi actively removes exudate and microscopic debris ‘to an extent that we have not experienced with other wound‐care modalities (20)’. Furthermore, in an agar model study, Rycerz et al demonstrated that, compared with continuous irrigation, NPWTi provided significantly better wound instillant distribution and coverage of not only the simulated wound bed but also tunnels and areas with undermining, thereby facilitating a more thorough cleansing (25). As noted by Wolvos, NPWTi also helped to change the viscosity of wound exudate, thereby enabling easier removal of drainage (18).…”

Clinical recommendations and practical guide for negative pressure wound therapy with instillation

“…As a result, the planktonic bacterial burden can be decreased, contaminants removed and the wound thus cleansed, without manual intervention. In addition, instillation with NPWT can also lower wound fluid viscosity, which in turn facilitates more efficient removal of exudates and infectious material through the foam and into the canister .…”

Negative Pressure Wound Therapy with Instillation in a Chronic Non-Healing Right Hip Trochanteric Pressure Ulcer

“…Compared to standard NPWT in an agar-based wound model, NPWTi-d displayed statistically significant doubling of wound-bed coverage [9]. NPWTi-d advances bacterial clearance as well as induces up to 43% more granulation tissue than traditional NPWT [10].…”