Download Presentation - Boeing Grand Challenges K

Behind the Black Box:
Medical Instruments
Why Do We Care?
• Medical equipment can be used to understand
the human body better.
– Diagnosis
– Monitoring
– Treatment
• Also 6 Billon Dollar
Industry.
Part of A Bigger System
• Throughout human history, engineering has
driven the advance of civilization.
• Even now, the world has multiple issues on
which engineers could be working.
• As a result, the National Academy of
Engineering (NAE) has defined some
challenges facing us in this century.
14 Grand Challenges
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Make solar energy economical
Provide energy from fusion
Develop carbon sequestration methods
Manage the nitrogen cycle
Provide access to clean water
Restore and improve urban infrastructure
Advance health informatics
Engineer better medicines
Reverse-engineer the brain
Prevent nuclear terror
Secure cyberspace
Enhance virtual reality
Advance personalized learning
Engineer the tools of scientific discovery
Some Background Anatomy Review
“Lub-Dub”
• The “lub” sound comes first in the heartbeat
and is the longer of the two heart sounds.
• The “lub” sound is produced by the closing of
the AV valves at the beginning of ventricular
systole.
• The shorter, sharper “dub” sound is similarly
caused by the closing of the semilunar valves
at the end of ventricular systole.
The Cardiac Cycle
• Systole: The atria contract and push blood into
the ventricles. The ventricles contract to push
blood into the aorta and pulmonary trunk.
• Diastole: All 4 chambers of the heart are in
diastole as blood pours into the heart from the
veins. The ventricles fill to about 75% capacity
during this phase and will be completely filled
only after the atria enter systole.
Circulation
Pulse Plethysmograph
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This pulsatile change in blood pressure results in a value change in the somewhat
elastic blood vessels in the body.
A pulse plethysmograph measures volume changes using light transmittance.
Some Math Review
Blood Oximetry
• Oxygenated blood absorbs light at 660nm (red
light), whereas deoxygenated blood absorbs
light preferentially at 940nm (infra-red).
• Pulse oximeters consist of two light emitting
diodes, at 600nm and 940nm, and two light
collecting sensors, which measure the amount
of red and infra-red light emerging from
tissues traversed by the light rays.
Now Something Fun
• Divide into 4 groups at the lab tables.
• You should have a device called a pulse oximeter on
your table.
• Take your heart rate without the pulse oximeter first.
• Have someone else record your waveform.
• Next ….