The Delay Phenomenon: Is One Surgical Delay Technique Superior?

Abstract

Background:Surgical delay remains a common method for improving flap survival. However, the optimal surgical technique has not been determined. In this article, we compare flap perfusion, viable surface area, and flap contraction of 2 surgical delay techniques.Methods:Male Sprague-Dawley rats were divided into 3 groups. In the incisional surgical delay group (n = 9), a 9 × 3 cm dorsal flap was incised on 3 sides without undermining, leaving a cranial pedicle. In the bipedicle surgical delay group (BSD, n = 9), a 9 × 3 cm dorsal flap was incised laterally and undermined, leaving cranial and caudal pedicles. Control group (n = 16) animals did not undergo a delay procedure. Ten days following surgical delay, all flaps for all groups were raised, leaving a cranial pedicle. A silicone sheet separated the flap and the wound bed. On postoperative day (POD) 7, viable surface area was determined clinically. Contraction compared to POD 0 was measured with ImageJ software. Perfusion was measured with Laser Doppler Imaging. The Kruskal-Wallis with Dunn’s multiple comparisons test was performed for group comparisons.Results:BSD preserved significantly more viable surface area on POD 7 (13.7 ± 4.5 cm2) than Control (8.7 ± 1.8 cm2; P = 0.01). BSD also showed significantly less contraction (21.0% ± 13.5%) than Control (45.9% ± 19.7%; P = 0.0045). BSD and incisional surgical delay showed significantly increased perfusion compared with Control on POD 0 (P = 0.02 and 0.049, respectively), which persisted on POD 3. This trend resolved by POD 7.Conclusion:BSD showed improved early perfusion, increased viable surface area, and reduced contraction compared to control, suggesting that BSD is the superior flap design for preclinical modeling.

Effectiveness of Different Surgical Flap Delay Methods and Their Systemic Toxicities

“…Gersch et al also used bipedicled and bilateral incisional (tripedicled) delay groups as a delay model in the cranially based modified McFarlane flap. 19 Following these delay stages, all flaps were eventually transformed into caudally based random pattern McFarlane flaps by coagulation of iliolumbar perforators in the later stage of the experiment. The purpose of this is to ensure the consistency of the necrosis area.…”

“…In BUSD, since we made bilateral longitudinal incisions, undermined and placed a silicone sheet under the flap, it was transformed into a bipedicled flap supplied by iliolumbar perforators caudally and thoracodorsal perforators cranially. Gersch et al also used bipedicled and bilateral incisional (tripedicled) delay groups as a delay model in the cranially based modified McFarlane flap 19 …”

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

“…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.…”