Flap Preconditioning with the Cyclic Mode (Triangular Waveform) of Pressure-Controlled Cupping in a Rat Model: An Alternative Mode to the Continuous System

Abstract

Background: Improving flap survival is essential for successful soft-tissue reconstruction. Although many methods to increase the survival of the distal flap portion have been attempted, there has been no widely adopted procedure. The authors evaluated the effect of flap preconditioning with two different modes (continuous and cyclic) of external volume expansion (pressure-controlled cupping) in a rat dorsal flap model. Methods: Thirty rats were randomly assigned to the control group and two experimental groups (n = 10 per group). The continuous group underwent 30 minutes of preconditioning with −25 mmHg pressure once daily for 5 days. The cyclic group received 0 to −25 mmHg pressure for 30 minutes with the cyclic mode once daily for 5 days. On the day after the final preconditioning, caudally based 2 × 8-cm dorsal random-pattern flaps were raised and replaced in the native position. On postoperative day 9, the surviving flap area was evaluated. Results: The cyclic group showed the highest flap survival rate (76.02 percent), followed by the continuous and control groups (64.96 percent and 51.53 percent, respectively). All intergroup differences were statistically significant. Tissue perfusion of the entire flap showed similar results (cyclic, 87.13 percent; continuous, 66.64 percent; control, 49.32 percent). Histologic analysis showed the most increased and organized collagen production with hypertrophy of the attached muscle and vascular density in the cyclic group, followed by the continuous and control groups. Conclusion: Flap preconditioning with the cyclic mode of external volume expansion is more effective than the continuous mode in an experimental rat model.

Cyclic helix B peptide promotes random‐pattern skin flap survival via TFE3‐mediated enhancement of autophagy and reduction of ROS levels

“…Random‐pattern skin flaps are convenient and are thus frequently used in plastic and reconstructive surgery (Dehdashtian et al, 2019; El Shaer et al, 2019). However, ischaemic necrosis of the distal flap portion is a major complication after flap operation that limits wider clinical application of skin flaps (Hong et al, 2019). The current understanding of flap survival suggests that inadequate blood supply and ischaemia–reperfusion injury are the primary causes of distal flap necrosis (Wu, Chen, et al, 2019; Zhou et al, 2019).…”

Preconditioning with Foam-mediated External Suction on Flap Microvasculature and Perfusion in a Rodent Model

“… 31 There is growing body of evidence in small animal preclinical models on the impact of wound healing and skin expansion models that has demonstrated the stimulation of external suction on increased angiogenic and adipogenic potential. 10 , 12 , 13 , 16 , 19 , 31 , 33 External volume expansion has previously demonstrated an influence on histological structure of tissues, and has shown to increase adipogenic potential 10 , 17 in fat grafting, and potential utility in diabetic and radiation in small experimental animal models. 8 , 13 , 34 …”

Early Experience with External Negative Pressure Delay in Free Anterolateral Thigh Perforator Flap Reconstruction

“…14 Other authors have reported similar findings of increased vascularity and improved flap survival in animal models when treated with external negative pressure. 15–19…”

“…The most common pressure setting reported is −125 mm Hg, and both continuous and intermittent suction settings have been utilized. 12–16 The report time period of treatment also varies, with the most common length of treatment being 5–7 days before intervention. 12–16 We present our initial experience using ENPD in free ALT flap reconstruction of upper extremity defects.…”