Autologous porcine VRAM flap model for VCA research

Area of Science:

• Surgical innovation in regenerative medicine and transplantation.
• Development of large animal models for preclinical research.

Background:

• Vascularized composite allotransplantation (VCA) requires robust animal models for studying immune rejection and graft survival.
• Large flap procurement in existing models can lead to significant defects and increased surgical risks.

Purpose of the Study:

• To detail surgical techniques and outcomes for autologous VRAM flap transplantation in swine.
• To evaluate neck flap isolation with induced ischemia as a control procedure for VCA research.
• To identify the most effective control procedure for future VRAM flap allotransplantation studies.

Main Methods:

• Two heterotopic autologous VRAM flap transplants were performed in Yucatan pigs.
• Two anterolateral neck flap isolations with induced ischemia were performed.
• Postoperative monitoring included clinical assessment, histological analysis, and transcutaneous oxygen/temperature measurements.

Main Results:

• Autologous VRAM flaps survived with successful abdominal defect closure and no complications.
• Neck flaps survived temporary ischemia but experienced necrosis and wound dehiscence, requiring reoperation.
• Histological analysis showed mild edema and inflammation in VRAM flaps, and mild edema in neck flaps.

Conclusions:

• A low-risk, technically feasible porcine autologous VRAM flap transplantation model was established.
• The VRAM flap model is suitable for future vascularized composite allotransplantation research.
• Neck flap isolation with ischemia presented higher complication rates, suggesting VRAM is a more viable control.