Abstract No. 171 Validating an ex-vivo bovine kidney pulsatile perfusion model with micro-CT evaluation of distal angioembolization

Abstract

Development of a reliable and affordable ex-vivo bovine kidney perfusion model has great potential for further advancing the field of interventional radiology (IR) and minimizing in-vivo animal research. We aim to validate our model for ex-vivo bovine kidney pulsatile perfusion by utilizing microscopic computed tomography (mCT) evaluation of distal angioembolization. Bovine kidneys were obtained directly from a local slaughterhouse. Immediately, the renal artery was flushed with heparinized saline. Organs were then transported on ice to the perfusion lab. Renal artery was cannulated to 3/8” tubing, and renal vein was cannulated with an inflated 16-Fr Foley catheter for collection of venous output. A roller pump was used for pulsatile arterial perfusion. Arterial tubing was set up with an in-line blood pressure (BP) monitor and a one-way valve for intraprocedural BP control. A 5 Fr sheath was placed in the arterial tubing to serve as vascular access. The kidney was mounted over a reservoir of heparinized saline perfusate. The pump would receive perfusate from this reservoir. Kidneys were perfused for 10 minutes prior to beginning the experiment. Two integrated-IR residents were primary operators with attending intraprocedural supervision in a DSA lab. A series of 4 ex-vivo bovine kidney perfusion protocols were successfully performed. Segmental embolization was performed using a 2.8 Fr microcatheter supported by a 5 Fr guiding catheter. Embolization was to contrast stasis. The following variables were collected: kidney pre- and post-perfusion weight, intraprocedural BP, embolic material volume delivered, DSA images, and distal embolization assessed by mCT vascular distribution. Average pre- and post-perfusion weights were found to have a statistically significant increase (P< .05). Intraprocedural BP averaged 140+25mmHg systolic and 61+14mmHg diastolic. 57 minutes were spent perfusing the organ. All post embolic DSAs revealed successful embolization. In a pulsatile perfused ex vivo bovine kidney, microbeads demonstrated stability, fair homogeneity, and microembolization below 40 um vessels without significant venous distribution. Our ex-vivo kidney pulsatile perfusion model is reliable, replicable, and provides a platform where microembolization experiments can be performed. This perfusion model has applications in translational and educational research.