Influence of recipient-bed isolation on survival rates of skin-flap transfer in rats

The effect of recipient-bed isolation with artificial barriers on skin-flap survival, compared to flap transfer without bed isolation, was evaluated i n a modified rat epigastric skin-flap model. The pattern of blood flow in t he raised flap with a proximal axial portion and distal random portion was confirmed by laser Doppler flowmetry. Forty rats were divided into four gro ups. Three of the groups had one of three different artificial barriers-sil icone, polypropylene, or gelatin sponge. In each of these three groups, one of the artificial barriers was placed between the flap and its recipient b ed after flap replacement. The flaps without bed isolation (Group 4) were u sed as controls. The survival area was measured 7 days postoperatively. Res ults demonstrated that necrosis in the groups with silicone and polypropyle ne barriers was significantly higher than in the controls. Histologically, neovascularization was shown in the flaps without artificial barriers. Fore ign-body reactions were observed in the flaps with bed isolation and among these, severe inflammation and congestion were seen in the flaps with polyp ropylene isolation. In this study, the authors demonstrated that the random portion of a rat skin flap could survive partially through imbibition of p lasma and the ingrowth of new vessels from the recipient bed. This neovascu larization can be prevented by recipient-bed isolation with an artificial b arrier. Bed isolation with a silicone sheet is suggested for use in the stu dy of rat skin-flap survival.