CURRENT PROCJECTS The Effect of AVF Size and Position on Distal Perfusion Focus: Alter diameter, length and position of fistula and monitor changes in hemodynamics of system CFD (Computational Fluid Dynamics) Modeling Focus: Alteration of fistula diameter and the resulting changes in flow patterns FUTURE PROJECTS The Hemodynamics of AVF and DRIL Bypass Focus: Understand hemodynamics of system with AVF and DRIL, study hemodynamics of DRIL and optimal treatment for ischemic steal. Mean Aortic Flow: 4.2 L/min Hollow Tygon tubing Features: Tubing length and thickness match vessel compliance and anatomy and includes venous return Glycerin and Water Features: Match blood viscosity Connectors with fabricated pressure taps Features: Non- Compliant tubing, capable of acquiring pressure measurements at each junction through pressure transducers, one-way valve included in venous return Hand compliance chamber Features: Column of water below column of pressurized air, accurately mimics compliance and resistance of hand capillary bed Heart Simulator Features: Ventricular and Venous Compliance chamber, ventricular and buffing chamber, two artificial valves, driven by Servo motor, outputs pulsatile flow Complete in Vitro Model of the Pulsatile Upper Extremity Arteriovenous Circulation: a Platform for Hemodynamic Testing and Modeling Ankur Chandra, MD1, Nicole A. Varble, BS2, Dan B. Phillips, Ph.D.2, Steven W. Day, Ph.D.2, Karl Schwarz, M.D.1, Karl A. Illig, M.D.1. 1University of Rochester Medical Center, Rochester, NY, USA, 2Rochester Institute of Technology, Rochester, NY, USA. IntroductionResultsConclusions Methods and Materials Current and Future Work Venous Compliance Chamber Ventricular Compliance Chamber Valve Viewing Chamber Buffing Chamber Ventricular Chamber Intersection of Arm Vasculature Subclavian A. Aorta Axillary A. Brachial Ulnar Radial Complianc e Chamber Distal Arm V. One-Way Check Valve Axillary V. Subclavian V. Body Resistance Collateral The experimental study of pulsatile arterial and venous hemodynamics is challenging. Mathematical modeling struggles to accurately represent the capillary bed/venous circulation while in vivo animal models are expensive and labor intensive. We hypothesized that an in vitro, physiologic model of the extremity arteriovenous (AV) circulation could be created as a platform for hemodynamic modeling and testing. In vitro upper extremity vascular simulator with pressure waveforms at specified locations Physiologically representative, in vitro, fluid model of the extremity AV circulation which incorporates: Vessel wall compliance Blood viscosity Capillary bed physiology Variation of all aspects of input hemodynamics (B.P., C.O., and SV) with heart simulator Applications: Ideal tool to study complex hemodynamics of dialysis access and steal physiology, device testing, surgical simulation L/min 1310 mL/min 1317 mL/min 1260 mL/min 1280 mL/min 29 mL/min 39 mL/min -20 mL/min 65 mL/min 136 mL/min 1375 mL/min 1410 mL/min 1260 mL/min 84 mL/ min Mean Flows and Pressures are labeled at the appropriate vessels and connectors above. Pressures [mmHg] are indicated by balloons: # Retrograde Flow Brachial A.: 121/54 mmHg (91.92 mmHg) SC V.: mmHg Distal Venous Return: mmHg SC A.: 125/55 mmHg (90.47 mmHg) CFD Model of brachial artery bifurcated with AVF