Data from: Development of an extracorporeal perfusion device for small animal free flaps

Background: Extracorporeal perfusion (ECP) might prolong the vital storage
capabilities of composite free flaps, potentially opening a wide range of
clinical applications. Aim of the study was the development a validated
low-cost extracorporeal perfusion model for further research in small
animal free flaps. Methods: After establishing optimal perfusion settings,
a specially designed extracorporeal perfusion system was evaluated during
8-hour perfusion of rat epigastric flaps followed by microvascular free
flap transfer. Controls comprised sham-operation, ischemia and in vivo
perfusion. Flaps and perfusate (diluted blood) were closely monitored by
blood gas analysis, combined laser Doppler flowmetry and remission
spectroscopy and Indocyanine-Green angiography. Evaluations were
complemented by assessment of necrotic area and light microscopy at day 7.
Results: ECP was established and maintained for 8 hours with constant
potassium and pH levels. Subsequent flap transfer was successful. Notably,
the rate of necrosis of extracorporeally perfused flaps (27%) was even
lower than after in vivo perfusion (49%), although not statistically
significant (P = 0,083). After sham-operation, only 6% of the total flap
area became necrotic, while 8-hour ischemia led to total flap loss (98%).
Angiographic and histological findings confirmed these observations.
Conclusions: Vital storage capabilities of microvascular flaps can be
prolonged by temporary ECP. Our study provides important insights on the
pathophysiological processes during extracorporeal tissue perfusion and
provides a validated small animal perfusion model for further studies.