Novel Noninvasive Hybrid Flap Preconditioning Surpasses Surgical Delay in the Murine Model.

Abstract

Ischemic necrosis in the distal portion of a flap is a challenging complication in plastic surgery. The authors hypothesized that a novel hybrid flap preconditioning (HFP) device combining foam-mediated external suction and nonsurgical delay can promote skin flap survival better than surgical delay. Twenty-eight mice were divided into 4 groups: a control group, in which a 4 × 1.5-cm dorsal flap was made with no preconditioning; a surgical delay group, in which surgical delay occurred 7 days before flap elevation; a foam-mediated external suction (FMES) group, in which foam-mediated external suction at -100 mm Hg was used 5 hours a day for 6 days, and the flap was elevated on the seventh day; and a hybrid flap preconditioning (HFP) group, in which silicone strips were applied along the contour of the foam interface. The same negative-pressure protocol was used as in the FMES group. Seven days after flap elevation, macroscopic, histologic, and Western blot analyses were performed. The flap survival rate was 46.25% (8.12%) in the control group, 68.72% (7.00%) in the surgical delay group, 57.03% (8.17%) in the FMES group, and 80.66% (3.27%) in the HFP group. Immunohistologic analysis of CD31 + cells in the distal end of viable tissue procured 7 days after flap elevation showed significantly higher angiogenesis in the surgical delay and HFP groups. Western blot results showed an increased expression of vascular endothelial growth factor in the surgical delay and HFP groups. The authors developed and fabricated a novel HFP device combining foam-mediated external suction and nonsurgical delay. The concept of HFP has proved to promote flap survival better than surgical delay. This study presented an innovative noninvasive method of flap preconditioning, which has been demonstrated to be superior to surgical delay in a murine model and holds promise for potential application in clinical settings.