Does treatment of split-thickness skin grafts with negative-pressure wound therapy improve tissue markers of wound healing in a porcine experimental model?

Continuous negative-pressure wound therapy improves the survival rate of skin grafts and shortens the time required for skin graft survival

BACKGROUND

The effectiveness of negative-pressure wound therapy (NPWT) in skin graft fixation has been demonstrated in several clinical studies. However, in vitro and in vivo studies on skin graft fixation with NPWT have been scarce. In this in vivo study, we aimed to determine whether NPWT fixation enhances skin graft survival and how it contributes to improving skin graft survival biologically.

MATERIALS AND METHODS

We harvested skin from the bilateral abdominal wall of 88 mice after anesthetizing them. Full-thickness skin grafts (FTSGs) were performed on contralateral harvest sites, and grafts were fixed using NPWT (continuous and intermittent modes), conventional compression methods, and wrapping with polyurethane foam as a control group. On days 5 and 10 of grafting, the survival rates of the FTSGs were evaluated. Immunohistopathological analysis and measurement of the expression levels of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF-2), and epidermal growth factor (EGF) were performed.

RESULTS

The survival rates of FTSG in the continuous NPWT group were significantly higher than those in the other groups. The number of capillaries in the dermis was significantly higher in the continuous NPWT group than in the other groups. In the wound bed, VEGF levels were significantly higher in both NPWT groups than in the other groups.

CONCLUSION

Continuous NPWT increases the survival rate of FTSGs and shortens the duration of skin graft survival.

Split Thickness Skin Graft of the Foot and Ankle Bolstered With Negative Pressure Wound Therapy in a Diabetic Population: The Results of a Retrospective Review and Review of the Literature

Split thickness skin graft (STSG) is a versatile procedure performed for the treatment of wounds resulting from varying pathology. This remains very useful because of its ability for quick healing and low complication rate. The surface of the foot and ankle is an area frequently affected by severe skin and soft tissue structure infections (SSTIs) whose treatment results in wounds. These infections and resultant surgical wounds are commonly seen patients with diabetes. The objective of the present study was to retrospectively evaluate initial healing and immediate post-operative outcomes following STSG application in a diabetic population when negative pressure wound therapy (NPWT) was used as a bolster. Ten patients were identified, including 11 surgical wounds, who underwent STSG bolstered with NPWT from January 2016 to October 2018. Mean follow-up was 13 months (range 1-33 months) with an average time to heal of 17 days (range 14-30 days) for 11 surgical wounds averaging 57 cm2 (range 6.3 - 91 cm2). Consistent improved outcomes have been demonstrated when compared to alternative bolstering techniques available in the literature making a STSG bolstered with NPWT a powerful tool in the reconstruction of diabetic foot wounds resulting from the treatment of infection.Levels of Evidence: Level IV.

Paracrine Factors from Irradiated Peripheral Blood Mononuclear Cells Improve Skin Regeneration and Angiogenesis in a Porcine Burn Model

Burn wounds pose a serious threat to patients and often require surgical treatment. Skin grafting aims to achieve wound closure but requires a well-vascularized wound bed. The secretome of peripheral blood mononuclear cells (PBMCs) has been shown to improve wound healing and angiogenesis. We hypothesized that topical application of the PBMC secretome would improve the quality of regenerating skin, increase angiogenesis, and reduce scar formation after burn injury and skin grafting in a porcine model. Full-thickness burn injuries were created on the back of female pigs. Necrotic areas were excised and the wounds were covered with split-thickness mesh skin grafts. Wounds were treated repeatedly with either the secretome of cultured PBMCs (Sec(PBMC)), apoptotic PBMCs (Apo-Sec(PBMC)), or controls. The wounds treated with Apo-Sec(PBMC) had an increased epidermal thickness, higher number of rete ridges, and more advanced epidermal differentiation than controls. The samples treated with Apo-Sec(PBMC) had a two-fold increase in CD31+ cells, indicating more angiogenesis. These data suggest that the repeated application of Apo-Sec(PBMC) significantly improves epidermal thickness, angiogenesis, and skin quality in a porcine model of burn injury and skin grafting.

Evaluation of Six Split-thickness Skin Graft Donor-site Dressing Materials in a Swine Model

Background:

Numerous dressings for split-thickness skin graft donor sites are commercially available with no conclusive evidence-based consensus regarding the optimal dressing choice. This study was conducted to identify which of 5 commonly used materials promotes wound healing most effectively for use on split-thickness donor sites in comparison with our standard dressing, Xeroform (petrolatum gauze).

Methods:

Twenty-four partial-thickness wounds were created on the backs of 4 pigs using a dermatome. Wounds (n = 4 per dressing type per pig) were treated with Xeroform, Opsite (polyurethane film), Kaltostat ( calcium sodium alginate), DuoDERM (hydrocolloid), Aquacel (hydrofiber), and Mepilex (silicone foam). Full-thickness skin samples were excised at 3 or 5 days and evaluated histologically for reepithelialization and inflammation. Comparisons also included incidence of infection, ease of use, and cost analyses.

Results:

DuoDERM elicited the greatest percent reepithelialization (81%) and Mepilex the lowest (33%) after 3 days (P = 0.004). All dressings demonstrated complete reepithelialization except Mepilex (85%) at 5 days. There were no infections and inflammation was mild among all treatments. Mepilex was easiest to use, whereas Aquacel, Kaltostat, and Opsite were most difficult (P = 0.03). Xeroform was most cost-effective and Aquacel most expensive. Combined scoring revealed DuoDERM = Xeroform > Opsite = Mepilex > Kaltostat > Aquacel.

Conclusions:

DuoDERM and Xeroform were most effective overall. DuoDERM tended to outperform all dressings in reepithelialization at 3 days, while Xeroform was least expensive, easy to use, and demonstrated rapid reepithelialization. These findings suggest that Xeroform may be preferred for use on large donor-site areas. DuoDERM may be more appropriate for small donor sites when healing time is a priority.