Plastic and Reconstructive Surgery, Global Open (Aug 2020)

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

  • Anita T. Mohan, MRCS, MBBS,
  • Lin Zhu, MD,
  • Gregory J. Michalak, PhD,
  • Alexis T. Laungani, MD,
  • Andrew J. Vercnocke, BS,
  • Steven L. Moran, MD, FACS,
  • Michel Saint-Cyr, MD, FRCS(C)

DOI
https://doi.org/10.1097/GOX.0000000000002739
Journal volume & issue
Vol. 8, no. 8
p. e2739

Abstract

Read online

Background:. Foam-mediated external suction (FMES) has previously shown to improve tissue microcirculation. We hypothesized that preconditioning fasciocutaneous perforator flaps with FMES would augment perfusion and demonstrate greater capillary recruitment. Methods:. Gluteal perforator flaps were designed on sixteen 400 g rats. Continuous FMES at −125 mm Hg was applied on one side (intervention) to precondition tissue for 5 days, with the contralateral side as a paired control. In group A, we assessed changes following pretreatment, after surgery, and 7 days postprocedure, and in group B, we evaluated changes during preconditioning alone. In group A (N = 8), control and intervention flaps were assessed using laser-assisted indocyanine green fluorescence angiography. In group B, flap regions were assessed using 4-dimensional computed tomographic angiography. All flaps were analyzed for microvessel density using micro–computed tomography and histological assessment using hematoxylin and eosin and CD3 immunohistochemistry. Results:. Thirty-two flaps were included in this study (N = 16 intervention and matched controls). Four-dimensional computed tomographic angiography demonstrated 17% greater tissue perfusion in preconditioned flaps (mean, 78.7 HU; SD, 8.8) versus controls (mean, 67.3 HU; SD, 15.7; P < 0.01). Laser-assisted indocyanine green fluorescence angiography showed a 30% higher mean absolute intensity in preconditioned flaps versus controls (P < 0.01). Postsurgery mean absolute intensity in preconditioned flaps remained 21% higher than in controls (P = 0.03). Preconditioned flaps demonstrated a 2-fold increase in mean vessel volume of 9.1 mm3 (SD, 7) versus 4.5 mm3 (SD, 3) in controls (P = 0.04); there was a 33% higher mean area fraction of CD31 in preconditioned flaps, 3.9% (SD, 3) versus 2.9% (SD, 3) in controls (P = 0.03). Conclusion:. FMES preconditioning has the potential to augment vascularity of tissue for flap harvest; however, further experimental studies are required to optimize strategies and evaluate long-term effects for clinical applications.