Science supporting negative pressure wound therapy with instillation

Abstract

A new method (V.A.C.ULTA Therapy System, KCI USA, Inc., San Antonio, TX) combines the benefits of negative pressure wound therapy (NPWT; V.A.C. Therapy, KCI USA, Inc.) with regulated, periodic instillation of user-selected topical wound solutions (V.A.C. VeraFlo Therapy, KCI USA, Inc.). In simulated wound model studies comparing solution distribution using NPWT with and without a soak phase, the instillation soak phase allowed for uniform solution distribution across the wound bed, whereas continuous (no soak) irrigation resulted in uneven coverage. Additional in vitro work illustrated that bacterial particle aerosolisation during wound cleansing was significantly decreased using NPWT with instillation (NPWTi) versus commercially available low-pressure wound cleansers (P < 0·05). In porcine studies, NPWT with saline instillation induced 43% more granulation tissue versus NPWT (P < 0·05) and was as effective at wound cleansing as pulsed lavage. These studies have demonstrated that NPWTi may be an effective wound management therapy that provides both wound cleansing and NPWT benefits.

Keywords: Negative pressure wound therapy; Negative pressure wound therapy with instillation; Periodic instillation; Reticulated open-cell foam; Wound cleansing.

Figure 1

Negative pressure wound therapy (NPWT)/NPWT with instillation (NPWTi) system (V.A.C.ULTA™ Therapy System) that combines NPWT (V.A.C.® Therapy) with the option for instillation therapy using NPWTi (V.A.C. VeraFlo™ Therapy) dressings. (Reprinted with permission from KCI Licensing, Inc.)

Figure 2

Fluid distribution (wicking) capabilities over time, comparing reticulated open‐cell foam (ROCF)‐G (V.A.C.® GranuFoam Dressing) to ROCF‐V (V.A.C. VeraFlo™ Dressing) in a compressed state 7.

Figure 3

Wound bed coverage by instillation solution via continuous irrigation (A and B) versus periodic‐instillation (negative pressure wound therapy with instillation, NPWTi) (C and D) therapy on an agar‐based complex wound model with undermining (yellow arrows) and tunnelling (red arrows) is indicated 8. (A and C) Full view of agar wound model. (B and D) Lateral sectioning of agar wound model to expose undermining and tunnelling portions. Note the lack of dye exposure in undermined and tunnelled portions of the agar wound model treated with the continuous instillation therapy (B) compared to the definitive staining in undermined and tunnelled portions treated with NPWTi (D). (Reprinted with permission from reference 8.)

Figure 4

Bacterial particles detected after cleansing treatments. Negative pressure wound therapy with instillation (NPWTi) therapies were significantly different from LPL w/Pressurised Can, LPL w/Spray Bottle #1 and LPL w/Spray Bottle #2, within the bacterial strain group (P < 0·05) 15. LPL, low‐pressure lavage; ROCF‐V, V.A.C. VeraFlo™ Dressing; ROCF‐VC, V.A.C. VeraFlo Cleanse™ Dressing; N/A, not applicable. (Reprinted with permission from reference 15.)

Figure 5

Graphical (A) and histological evaluations (B and C) of granulation tissue production in a porcine full‐thickness excisional wound model comparing negative pressure wound therapy (NPWT) with reticulated open‐cell foam (ROCF)‐G (B) and NPWT with instillation (NPWTi) with ROCF‐V (C) after 7 days of treatment 7. Following the 7 days of therapy, NPWTi resulted in a significant increase (P < 0·05) in granulation tissue thickness compared with traditional NPWT. (B and C: Reprinted with permission from KCI Licensing, Inc.)

Figure 6

Fluorescent images prior to (A) and post (B) cleansing of the dextran‐inoculated porcine wound via negative pressure wound therapy with instillation (NPWTi) 15. (Reprinted with permission from reference 15.)