Download BIOE_360_Team_Template_Case_2

BIOE 360 Case 2
Team #: Names
Introduction
Case information:
Cardiopulmonary resuscitation (CPR) is a commonly used technique to maintain blood flow to
the body in cases where the heart stops. Resuscitation was invented in 1950 first with the use
of expired air to maintain oxygenation and then in 1960, CPR as we know it today was
introduced combining expired air with chest compressions.
Adult CPR instructions were originally 100 compressions per minute, but now are 100-120 per
minute. For adults, a compression is defined as at least 2 inches compression of the chest, but
has been cited as 2-2.4 inches as well. Some physicians say that injury is likely beyond 2.4
inches of compression. Further, the American Heart Association[1] recommends two rescue
breaths after the 100 compressions before resuming compression.
For infants, the American Red Cross[2] recommends giving two rescue breaths and then using
2 fingers to deliver 30 quick compressions at about 1.5 inches deep followed by two more
breaths. For larger children, they recommend the same 30 compression cycle, but at 2 inches
deep followed by 2 breaths.
Despite widespread training and education in CPR, a five-year study out of the University of
Minnesota Medical School studied CPR which analyzed over 300,000 patients found survival
rates average only 5 percent. They cited these results, in part, because CPR is inherently
inefficient providing less than 25 percent of normal blood flow to the heart and brain[3].
Your job is to create a model of the circulatory system to determine if the recommendations are
sufficient to provide flow to the brain and heart and determine the efficiency of CPR. Everyone
will create a generic model for the first phase of the case for review then you’ll be given a
specific patient type to test where you can change your model parameters to make a
recommendation for the CPR process for that patient. At the conclusion of the case, we will
host a CPR class where each team will review the protocol for their patient.
____________________
American Heart Association News (October 15th, 2015) |Blog, CPR. Retrieved from
http://news.heart.org/%EF%BB%bfnew-resuscitation-guidelines-update-cpr-chest-pushes/
American Red Cross Retrieved from http://www.redcross.org/take-a-class/cpr/performing-cpr
University of Minnesota. (2011, March 1). New CPR method increases survival rate by 50
percent, study suggests. ScienceDaily. Retrieved February 13, 2017 from
www.sciencedaily.com/releases/2011/03/110301111507.htm
Timeline
Date
Feb 17th
Feb 20th
Feb 22nd
Lecture
Basics of compliance and resistance with flow
Compartment models
Non-steady state flow in CV
Assignment Due
Feb 24th
Feb 27th
Mar 1st
Mar 3rd
Oxygen flow in lungs
Work Day
Work Day
Work Day – Guest Prof Dr. Smith
Problem Set and Models Due
– Amos out of town 
Mar 6th
Receive model feedback and patient type
th
Mar 8
Work Day
Mar 10th
EOH – No Class!
EOH
Mar 13th
Case Presentations
Mar 15th
Case Quiz Day
Amos out of town 
*Additional working time outside of class and in office hours – see Piazza for office hours and
Matlab help sessions
Module Lessons
Questions:
I.
II.
III.
IV.
Ribcage mechanical properties
a. Force transduction into heart - what is relationship in flow in arteries and
relationship with valves?
b. At what force will ribs break??
Fluid dynamics of Cardiovascular system
a. Elasticity of blood vessels (resistance and compliance of different vessels)
b. Compliance - how does it vary among population?
c. Time for refill of heart between beats
d. Blood pressure and gravity effects?
e. What are adequate perfusion levels for different organs?
f. Pulsatile flow versus steady state flow models?
Cardiopulmonary Resuscitation
a. How compression affects flow?
b. Threshold for flow
c. Oxygen modeling - how much delivered?
How do you capture success in CPR???
Learning outcomes:
I.
II.
III.
IV.
V.
Create a Matlab compartment model for a flow system
Determine which flow parameters change across a patient population
Model pulsatile flow in the cardiovascular system
Correlate multiple factors into a comprehensive model of CPR including force and
frequency of compression with cardiovascular flow dynamics
Recommend a CPR procedure based on evidence and understanding of models
Resources
Matlab Onramp – Matlab training module https://matlabacademy.mathworks.com/ Attach your
certificate to the problem set if you complete it.
Physiology Textbooks: I have several others in my office beyond your BIOE 302 text
Lectures:
1.
2.
3.
4.
Basics of compliance and resistance with flow
Compartment models
Non-steady state flow in CV
Oxygen flow in lungs
Problems:
1. What is the distribution of blood flow at rest? Why might the blood flow distribution
change during exercise?
2. (a) Determine the rate of oxygen removal from the lung venules for the following
conditions: inspired air containing oxygen at 21% partial pressure, alveolar partial
pressure of 105 mmHg, blood flow rate of 5 L/min, respiration rate of 10 breaths per
minute. The alveolar volume is the difference between the respiratory volume and the
dead volume (0.15 L). Assume that T=37C and R=0.08206 L atm/(mol K) and 1
atm=760 mmHg.
3. During exercise, the cardiac output can rise to 25 L/min from a resting rate of 5 L/min.
The heart rates of a well-trained athlete might rise from 60 beats/min to 105 beats/min
and the mean arterial pressure may rise from 100 to 130 mmHg, whereas the heartrate
of a sedentary person might rise from 72 beat/min to 125 beats/min and the mean
arterial pressure may rise from 100 to 150 mmHg. Determine the volume of blood
ejected during each heartbeat (stroke volume) and the peripheral resistance for an
athlete and a sedentary person. Assess the power of the left side of the heart for an
athlete and the sedentary person using the following where P=Power, ̅̅̅a
𝑝𝑎 is mean
arterial pressure, V is ventricular volume, W is work, and ƒ is heart rate in beats/second.
𝑃 = 𝑊𝑓 = 𝑓 ∫ ̅̅̅𝑑𝑉
𝑝𝑎
4. Calculate the tension needed on the interior side of the mitral valve leaflet to maintain
the valve closed after closure and during ejection. Assume that the valve closure has a
pressure difference of 1.5 mmHg between the ventricle and the atrium. The arterial
pressure is 3 mmHg and the exposed area of the leaflet is 50.2 mm2. The internal radius
is 1cm and the external radius is 1.2cm. Use the following equation to determine the
tension needed on the inside and outside of the valve leaflet. 𝑝𝑖𝑛𝑛𝑒𝑟 − 𝑝𝑒𝑥𝑡𝑒𝑟𝑛𝑎𝑙 =
𝑇𝑖𝑛𝑛𝑒𝑟
𝑇
+ 𝑟2𝑒𝑥𝑡𝑒𝑟𝑛𝑎𝑙 In conditions where heart valves stiffen, the tension that they can
𝑟2
𝑖𝑛𝑛𝑒𝑟
𝑒𝑥𝑡𝑒𝑟𝑛𝑎𝑙
withstand reduces to 2mN external and 0.5 mN on the interior surface. What changes
about the valve leaflet surface in order to cause this effect?
Assessments
Problem solutions: Attach neatly handwritten, and/or LaTex, or Matlab solutions to each
problem and explain how it helped you reach the learning outcomes for the unit. No Wolfram
Alpha.
Case Solution: Attach neatly handwritten, and/or LaTex, or Matlab solutions to the case and
conclusions drawn relating to the case questions.
Team assessment
Preparedness: How much time and effort did you put into the unit?
Thoroughness: Did your entire group give an adequate summary of the case and solution using
concepts from the learning activities?
Effectiveness: How useful was your discussion in helping understand the material?
Connections: How significant and helpful was your connection between the case and the
learning activities?
Creativity: How innovative were you in making the material “come alive”?