Jon Klein ISE Project Manager

Nguyen Vu ME Technical Lead (MSD1)

Kyle Menges ME Technical Lead

Christine Lowry ME Design Engineer

Chris Stein ME Design Engineer

Priya Narasimhan

EE Electrical Engineer

Julie Coggshall ISE Systems Engineer

•Customer Needs•Top 10 Specifications•Static Subsystem Concept•Hemolysis Design and Testing•Automated Pressure Curves Design and Testing•Physiological Sub-System Concept•Physiological Design and Test Results•Project Evaluation

Design and build a test loop to help in LVAD development by characterizing the pressures and flows associated with the device as well as its impact on blood.

1. Generate pressure and flow curves for static system (automatically adjusted)

2. Extracting fluids while running to determine damage to blood

3. Process data to generate pressure and flow for dynamic system (scaled model of the physiological circulatory system working with a PVS)

Engr Spec #

Metric UnitsIdeal Value

LowerLimit

UpperLimit

ES1 System Leakage# leak

locations0 0 2

ES6 Portability minutes 45 1 60

ES9 Cost *Renegotiated from MSD1 U.S. Dollars 3000 1000 4000

ES13 Pressure mm Hg 100 0 200

ES14 Pressure Accuracy mm Hg 0.2 0.001 0.5

ES15 Flow Rate liters/minute 6 0 10

ES16 Flow Rate Accuracy liters/minute 0.05 0.001 0.1

ES17 Temperature degrees C (F) 37 (98.6) 21 (70) 49 (120)

ES18 Temperature Accuracy degrees F 0.1 0.01 0.5

ES22 System LxWxH inches 48x36x3036x12x1

260x48x3

6

Concept Summary• LVAD (A)• Reservoir (B)• Flow Sensor (C)• Automated/Manual Resistance (D)• Quick-Connect Drainage (E)• Differential Pressure Sensor (F)

• Water Bath (G)•Thermocouple (H)• Extraction Needle (I)• Circulation Pump (J)• Heating Element (K)

DC

A

B J

H

E

G

I

K

FDirection of Flow

0

50

100

150

200

250

0 2 4 6 8 10

Pre

ss

ure

-m

mH

g

Flow - Lpm

Biomedicus Performance Curve

500 rpm 1000 rpm 1500 rpm 2000 rpm

500 rpm SD 1000 rpm SD 1500 rpm SD 2000 rpm SD

Automatically generated performance curves

Less modular design than intended – but still meets specs

The test loop does not cause significant hemolysis

• Arterial Air Pressure (G)• Reservoir Temperature (H)• Arterial Compliance tank (I)• Arterial Pressure Sensor (J)

A B

D

G

EF

• Flow Sensor – Full Loop (A)• Resistance (B)• PVS (C)• Flow Sensor – LVAD Bypass (D)• Differential Pressure Sensor (E)• LVAD (F)

H

J

I

CDirection of Flow

• Arterial tank pressure decay = 0.8 mmHg/sec• Sufficient pressure is supplied by pressurizing the tank to prevent the ventricle of the PVS from collapsing• Initial Compliance value = 50 mmHg/mL (based on 2550 mL of air and 30 mmHg air pressure)• To achieve a Compliance value = 2 mmHg/mL the arterial tank should be filled with 3700 mL of fluid and pressurized to 100 mmHg.

•Successfully Fulfilled all Customer Needs •Met 15 out of 20 Specifications including Budget

- Did not verify arterial compliance and Temperature – behind Schedule- Did not obtain performance using Glycerin mixture – behind Schedule- Accuracy of Temperature and Flow rate were not well defined in

initial development of specifications – meets customers needs

• Investigate the need for automated temperature control when performing tests• Verify Compliance using PVS and LVAD ~ 2 mmHg/mL• Automate Compliance tank pressurization• Verify program compatibility with multiple pressure sensors and flow meters• Verify the effect of pressure drop using a quick-connect during LVAD performance characterization• Increase the range of the automated test curves• Reduce test loop footprint• Improve fill/drain system to reduce set-up and take-down time

The P09021 Team would like to express its appreciation and gratitude to those who contributed to the progress of this project including:

• Dr. Steven Day• Mr. John Wellin• Dr. Richard Doolittle• Dr. Daniel Phillips

•Mr. Robert Kraynik• Dr. Olles, Dr. Cheng, Dave, Jim, Steve, Jess and the LVAD Research Team