Megan Foran, Danny Jones, & Frank MoynihanDr. Bob Wilkinson, Ph.D.
Need
Starling’s Law can be difficult for cardiophysiology students to visualize
To aid comprehension, students need an interactive learning model to supplement the lecture and reading material
The model should allow the students to control the variables of mechanical circulatory regulation:Stroke Volume, Heart Rate, and
Peripheral Resistance
Specific Design Requirements
Design SpecificationsPortable & Easy to Use
2-5 kg; 1-2 m in circumferenceRelatively Inexpensive (<$500)SustainableDiscrete structures
Left ventricle, Arteries, Veins, Resistance Vessels (Capillary Bed)
Mechanical Pump (LV), controlled by student, supplies power to the system
Variable resistance in capillary bed: (0,∞)Variable fluid volume within the system: (0,3 L)
Details of the Chosen Design
Elements of the DesignBiological Component Mechanical AnalogFluid Left VentricleArteries and VeinsResistance Vessels
Variable Resistance Mechanism
WaterPrimer BulbChambersPVC TubingNeedle Pinch Valves
FluidWaterCheapSimpleAbundantSafe
Left VentricleSierra ¼’’fuel line primer bulbMechanical, controlled by the studentTwo valves allow for unidirectional flowBarbed fittings
Sierra ¼” Fuel Line Primer BulbMade by iBoatsFlouroelastomer$18.27 eachLead time: 2-5 days
Arteries and VeinsClear PVC chambersAir and water levels model compliance
Graduated markings Threaded cleanout adapter and plug
Arteries & Veins Variable compliance stopcock
Shallow base cap$171.81 eachLead time: 1-2 weeks
Resistance Vessels¼” PVC tubingLow rigidityDurableLow costsVariety of sizes and fittings
Lead time: 2-5 days
Resistance MechanismNeedle Pinch Valves
DurableLow cost: $41.00 Mechanical InputSafeCompact SizeResistance (0,∞)
Conclusions
Did we solve the problem?Improved sustainability Consistent visual feedbackImproved resistance mechanism
Increased user-friendliness and simplicity
Future DirectionsTeaching Heart team will not continue on to BME402
Willing to stay in touch with the client to provide necessary support
What was learned?Communication is key, working together much more effective
Realistic goals and deadlines
What would be done differently?
Improve communication with client, focus on the clients needs
More innovative design concept
More specific project management
Intellectual Property
Teaching Heart team not seeking IPRelinquishing any potential IP to the client
Works CitedChamber, luer valves and fittings, adapters
<http://www.coleparmer.com/>PVC pipe, fittings,valves
<http://www.muellerindustries.com/products>Tubing, valves, fittings
<http://www.mcmaster.com/>."Primer Bulb." EPA Certified S : Attwood
Marine. Attwood Marine Products. http://www.attwoodmarine.com/store/product/epa-certified-primer-bulb.
US Plastics <www.usplastic.com>.
Questions?