Hypoxic preconditioning of the skin graft donor area: Clinical and morphological assessment

Abstract

The aim of the study was to evaluate the method of hypoxic preconditioning of the donor area using clinical and morphological assessment of the autologous dermal transplant (skin graft). Materials and Methods. The transplants were prepared from the skin donor area after hypoxic preconditioning. Reparative regeneration, skin graft angiogenesis and the cosmetic status of the donor area wound upon healing were studied. To this end, five patients with diabetes-associated soft tissue wounds underwent classic free skin plastic surgery (control group), and five patients underwent the similar operation preceded by hypoxic preconditioning of the donor zone (study group). On day 5 after the surgery, morphological and immunohistochemical examination of the skin transplant was performed; on day 14, the area of engraftment was evaluated. Results. On day 14, the area of engraftment of the autologous transplant in the control group was 56 [52; 64]%, and in the study group — 91 [84; 95]% (p=0.007). The healing of the donor area wounds in the control group was detected on day 18 [16; 21], in the study group — on day 14 [12; 17] (p=0.002). In the intravital histological staining of the biopsy specimen, cell-enriched skin fragments were found in the study group, whereas only cell-depleted skin fragments were observed in the control group. Upon the double sequential immunohistochemical staining with antibodies to Ki-67 and CD31 antigens, increased proliferation of endothelial cells of the dermis was noted in the study group, with the proliferation index of 29 [22; 33] versus 17 [13; 24]% in the control group (p=0.011). The increased levels of antibodies to VEGF and Fli-1 in the study group also pointed to the active angiogenesis in these patients. Conclusion. The results of the intravital histological and immunohistochemical study indicate that hypoxic preconditioning of the donor area can serve an effective tool of increasing the reparative regeneration and angiogenesis in the skin graft.