Preconditioning by Pressure Controlled Cupping Enhances Survival of Random Flap in Rat Model

Abstract

INTRODUCTION: Flap survival is essential for the success of soft tissue reconstruction, and surgical and medical methods aimed to increase flap survival have been previously introduced. Flap survival is affected by the innate vascular supply, therefore traditional methods of preconditioning mainly target vasodilatation or vascular reorientation to increase blood flow to the tissue. External stress on skin such as external volume expander or cupping induces vascular remodeling which were adopted in the field of fat grafting or Asian traditional medicine. MATERIAL AND METHODS: In this study, we used a rat random flap model to study the effectiveness of a preconditioning using externally applicable device (cupping) at the flap site through which negative suction was directly applied on skin. Flap surgery was performed after preconditioning for 30 minutes every 5 days, followed by 9 days of postoperative observation (Figure 1).Figure 1: Experimental model of preconditioning with an external negative pressure chamber.RESULTS: Flap survival was assessed as the area of viable tissue compared to a control group.The results showed 19.03±7.6% improved viability of the flap following negative pressure preconditioning. Tissue perfusion was increased by 24.23±10.38%, and histologic analysis of H&E, CD31 and Masson-Trichrome staining showed increased vascular density in the subdermal plexus and more organized collagen production with hypertrophy of attached muscle. CONCLUSION: Our data suggests that mechanical stretching caused by externally applicable device induces vascular remodeling, which leads to increased tissue perfusion and enhances flap survival.