Using Delay Principle to Create Two Viable Flaps Within one Distant Pedicled Flap: How We Did it-A Case Report.

Abstract

From the time reconstruction is being performed, delay is a part of standard surgical staged procedure, wherein the procedure results in inducing ischemia to the tissues and hence flap viability.[1] We present here a case, wherein we did a delay from the distal margin of an elevated flap, which bisected a single flap into two flaps to provide cover to two different regional defects with one flap acting as a distant pedicled flap and the other as a local transposition flap. A 24-year-old man presented with high-tension electrical burns with multiple exposed bones at multiple locations. The patient had 4-degree burn with an exposed left iliac crest bone and an exposed ulnar bone ([Fig. 1A, B]). The patient was planned for a single pedicled thoraco-umbilical flap (TU flap), which could cover both the ulna and iliac crest bones, the intention was to resurface two exposed bones with a single pedicled flap of two different anatomical regions. After 3 weeks, the flap was delayed from the distal margin and bisected from the middle of flap to produce two different individual flaps to resurface both the exposed bones without any pull in the opposite direction; hence flaps were lying snugly on their respective position ([Fig. 2]). The delay to bisect the flap was done in two stages of 5 cm, 7 cm length, respectively, with an interval of 1 week. After bisecting the whole flap, the inset was given to cover both the defects without any tension ([Fig. 3A, B]). The mechanism of delay makes the flap ischemic, wherein the length to breadth ratio of the harvested flap tissue may also be increased.[2] [3] Partial inset requires a staged delay that will help in increasing the dilatation of the existing vasculature, with proliferation in the choke area;[4] also, it obtains perfusion from the recipient bed. Most of the time, the standard practice of performing delay is from the base of the flap; in our case, a TU flap with the per umbilical perforator being the main supply was elevated. The delay principle was used in bisecting the flap in the middle with an intention to increase blood supply[5] in both halves of the flap to create two different flaps. Being an electrical burn, we were skeptical to perform a microvascular flap, in view of the high rates of failure due to intimal vascular damage. Delay done from the distal margin of the flap has been described for the first time. We conclude that the principle of delay may be applied in creating two viable flaps within one distant pedicled flap, with adequate care being taken on the timing of delay, length of incision on the flap, and the area of inset given on the defect.