Negative pressure wound therapy versus gauze dressing for Pseudomonas aeruginosa infected wound

Objective To compare the effect of negative pressure wound therapy (NPWT) and conventional gauze dressing on Pseudomonas aeruginosa infected wound healing. Methods Eighteen Bama miniature pigs were included in this study, and they were randomly divided into experimental group (n=9) with negative pressure wound therapy and control group (n=9) with conventional gauze dressing. A 5 cm×5 cm full-thickness wound infected by Pseudomonas aeruginosa was created on back of each pig. After the infected model was established successfully, the sizes of wounds were evaluated quantitatively, and muscular tissues were collected for analysis of VEGF and TGF-β1 expression at day 0, day 4, day 8, day 12 and day 16. Results The quantitative analysis of wound healing degree showed the wound size in NPWT group was significantly smaller than that in the control group at day 8, 12 and 16 (all P< 0.01, day 16, 15.6±5.1 mm vs 28.7±6.5 mm);granulation tissue thickness in the NPWT group was significantly greater than the control group at day 4, 8, 12 and 16 (all P< 0.01, day 16, 13 236.4±305.8μm vs 9 451.24±491.3μm). At day 16, the expression level of VEGF in NPWT group was 1.25 times of the control, TGF-β1 1.3 times, area of newborn capillaries 1.28 times (P< 0.01, respectively). Conclusion The healing of Pseudomonas aeruginosa infected wound is faster under negative pressure wound therapy and the new granulation tissue thickness is also relatively greater in NPWT group, which may be one of the mechanisms of negative pressure wound therapy to promote wound healing.