Vacuum Assisted Flap Delay, a Novel Strategy to Increase the Flap Survival: An Experimental Study in Rabbits

Flaps have been the mainstay in the practices of many plastic surgeons. Vascular compromise, which is the most common complication of flap surgery, has lead to the quest for strategies warranting better flap outcomes and survival. Flap delay procedures have been developed in this background. Surgical delay of the flaps has been the golden standard technique for flap delay. However, it requires two sessions of surgery which is a major drawback. Efforts have been made to omit one session and increase the patient safety and decrease the cost of the treatment. Thus chemical and physical delay techniques have be developed. [1]  Topical negative pressure has been used for assisting the wound closure. Molecular mechanisms explaining the effects of vacuum have been studied in depth.[2] Verified effects of vacuum like vascular induction, and some other similarities in molecular responses to surgical delay and topical negative pressure has led to the idea that it could be used for induction of neovascularization and increased vascular density in the flaps. For this purpose, in a rabbit model, the authors used a topical negative pressure system for induction of delay and compared the results with surgical delay and the negative control groups. Ten rabbits were in each group and contralateral side was used as normal control skin. The flap area, necrosis area, necrosis ratio, histomorphometric vascular density, immunohistochemical evaluation of neovascularization (CD31/CD34), Laser Doppler images and computerized tomography contrast uptake were used to evaluate the methods. In all the parameters, the vacuum assisted flap delay was equivalent to surgical delay. Both were superior to non-delayed flaps. Vacuum assisted flap delay was equivalent to surgical delay in all parameters. The mechanism of action in the vacuum assisted flap delay remains to be clarified.  In the clinical setting, vacuum assisted flap delay has the potential to bypass the surgical delay. It is cheap, safe and practical. The clinical significance should also be studied in large series. However, vacuum assisted flap delay seems to be promising method.