1. MSD Project by Joe Tartakoff

2.  Affects 5 million in US with 670,000 new cases/year  VADs used for advanced heart failure http://nursingcomments.com

3.  Bridge to Transplant surgery Thoratec Corporation Annual Review http://texasheart.org

4. www.jarvikheart.com  Heartmate II: 29% of patients experience a driveline infection www.thoratec.com

5. Customer Need # Importance Description CN13Reduce the magnitude of traumatic forces on the port connection that passes through the skin CN23Reduce inflammation and infection incidence at the interface between the skin and the foreign body CN33Driveline cable always has a direct connection to a power source and a motor controller signal (an internal battery and motor controller must be implemented) CN43Port makes a reliable connection for the Motor Controller signal while connected CN53Port material facilitates tissue integration (allows skin cells to grow into the material to increase adhesion and force needed for disruption) CN62Driveline cable has degree of flexibility between the transcutaneous interface and the motor connection to reduce fatigue failure (this is where the driveline enters the motor housing) CN72Port connection needs to be easy to make for elderly patients CN82Backup power lasts long enough for the user to seek assistance or take a shower. CN92Internal motor controller and battery need to be small enough to be implanted along with the pump CN102For surgical implantation, the transcutaneous port needs to be able to be sutured to the skin. CN111Internal motor controller and battery need to be able to handle environment of body: temperature, corrosive fluid, electrically isolated to protect against defibrillation CN121Handle purulent drainage overflow if infection occurs (infection will produce pus which accumulates at the port/skin interface)

6. Project Functional Decomposition Sense Cable Break Regulate Power Run Pump Generate Motor Control signal (Analog duty cycle) Recharge Internal battery External Power: 2 (12-14 V DC ) Batteries Power Cable: External Motor Control Signal (analog duty cycle) Accept cable into port Transmit Motor Control Signal Allow cable to break away

7.  88 Pa shear stress  0.33 N outward force Brown, R. A. Kelly, D. J. Marenzana, M. Prendergast, P. J. “A collagen-based interface construct for the assessment of cell- dependent mechanical integration of tissue surfaces.” Springer- Verlag. 8 March 2006.

8. SourceFunctionSpecification (metric)Marginal Value Ideal Value UnitsComments S1CN1SystemMax force transmitted directly outward 31NThis is the force directly perpendicular to the skin surface S2CN6SystemSpring constant of cable 750N/m S3CN8SystemBackup Support Time1530Min S4CN3SystemPower transmitted 8-10Watts S5CN3,4,8SystemRecharge time6030MinHow long it takes for the internal battery to recharge S6CN9SystemVolume of Battery/MC unit 0.0040.003m3m3 Based on size of peritoneal cavity in chest (pocket it will be implanted in) S7CN3SystemBattery Voltage 12 or 14 Volts (DC) 12 V Nickel Metal Hydride (NiMH) or 14 V Li-Ion (Current batteries used by Thoratec) S8CN4SystemBackup power switch- over time 5<1secMaximum allotted time for VAD to be inactive during switchover S9CN10SystemSuture Mode53mmIf suture holes are chosen, they must be 3-5mm apart for proper integration S10CN11SystemOperating Temperature95100 oFoFOperable in human body temp S11CN11SystemCurrent resistance for defibrillation 2045A200 J at 50 Ω (http://www.resuscitationcentral.com/ )http://www.resuscitationcentral.com/

9.  ME Heavy: 3 ME, 2 EE  EE Heavy: 2 ME, 3EE DisciplineHow Many? Anticipated Skills Needed EE2 Design the backup power system needed when the port disconnects. This will include the selection of a battery and a motor controller unit in addition to a switchover circuit. Skills needed are circuit design (board design/layout and testing), selection and analysis of power sources/systems, and knowledge of electromagnetics. ME2-3 Mechanical engineers will design the port, power cable, and breakaway system utilizing 3D CAD, Finite Element Analysis, stress and dynamic analysis. Additional knowledge of biomaterials, composites, and machining will aid in material selection and prototype fabrication. ISE1 Aid in the design of the port breakaway system through knowledge of materials science, materials processing, and ergonomics (how patients will interact with the system).