Criteria for Success: To be successful you will make sure you complete diagrams as instructed in the tasks, including proper values on the x & y-axis as well as labeling those.

Question

Criteria for Success: To be successful you will make sure you complete diagrams as instructed in the tasks, including proper values on the x & y-axis as well as labeling those. Make sure to label ESV, EDV, aortic and mitral valve opening and closing, and Isovolumetric relaxation and contraction where possible on the diagrams regarding blood volumes and pressure. You also need to make sure to list or provide explanation where necessary or where it is asked in the tasks. A successful submission would be very clear and easy to read and it would be easy to see the differences in pressures and volumes based on the given situations. For submission, you can submit them as a pdf or image from a phone if you are drawing these at home. I also suggest looking at the homework you have completed and the provided examples to help you in completing these tasks. 

Case Studies Tasks:

1. John recently visited the Doctor and was informed he has a blood pressure of 185/115 mmHG. Diagram a graph/loop for pressure vs volume (Volume Pressure Loop). The graph should contain a normal pressure to volume graph in a healthy heart and also a pressure vs. volume graph for John hypertension. You also need to list what specific factors could contribute to John's blood pressure being high? Make sure to label the diagram as described above.
2. Revisiting Jane: Jane was riding her horse on a warm sunny day (101 degrees Fahrenheit) when suddenly her horse stopped and reared up in the air. Jane was not prepared for this and fell hard backwards into the ground. As she hit the ground Jane's leg was gashed open by a large, sharp boulder that she fell next to. Jane began to bleed severely. Jane's pulse seems to be low (or hard to find) and her respiratory rate is at 22 bpm. Jane's body spends the next couple hours physiologically compensating for her blood loss. Based on your knowledge of the cardiovascular system complete the following: Make a graph of Jane's cardiac output/venous return (y-axis) vs (as a function of) her central venous pressure (pressure in the veins). Provide two points on the curve that represent (A) before she fell off the horse and (B) after she fell and suffered significant bleeding. Just use general numbers for central venous pressure (2-8 mmHg) and cardiac output of (2-7 Liters) Make sure the pressures and L/min are labeled correctly on each axis. Then list any compensatory mechanisms (physiological adjustments) the body is using to return the cardiac output to normal while bleeding.
3. Sarah was recently diagnosed with an obstructive lung disorder. In their diagnostic process the doctors completed a Forced Vital Capacity test on Sarah to determine her lung function. Based on this, (A) diagram a Vital Capacity test with lung volumes for a healthy individual and on the same graph include the VC test with lung volumes for Sarah's diagnosis. The doctors also found that Sarah's oxygen saturation was at 87%. Therefore, (B) diagram an oxygen saturation curve graph that shows a normal oxygen saturation curve vs. a curve representing Sarah's condition. Also list out the factors that can impact oxygen saturation for Sarah.
4. Tyreke has been putting himself through a strict diet and exercise regiment. In the last week, he was feeling some irregularity in his heart rate and heart beat. He decided to visit a doctor and found that he was suffering from Hyperkalemia. Use a diagram to explain how Hyperkalemia could impact cardiac pacemaker and contractile cells. Your diagram should show how Hyperkalemia causes changes. Make sure to include the following items at a minimum in the diagram(s):
5. mV (Membrane Potential in millivolts)
6. Na+
7. K+
8. Ca+
9. Slow acting channels
10. Fast acting channels
11. -40mV
12. -60mV
13. -90mV
14. Pacemaker potential
15. Depolarization
16. Repolarization
17. Hyperpolarization
18. Absolute Refractory Period

Answer 1

To create a pressure-volume loop for John's hypertensive heart and a healthy heart, we need to understand the different phases of the cardiac cycle and how they relate to pressure and volume changes in the heart. The cardiac cycle consists of two main phases: diastole (relaxation) and systole (contraction). The pressure-volume loop represents these phases and their corresponding pressure and volume changes in the left ventricle.

Here's a step-by-step explanation of how to create the pressure-volume loop:

1. Label the axes: The x-axis represents the volume (mL) and the y-axis represents the pressure (mmHg).

2. Draw the normal pressure-volume loop:

a. Start at point A, which represents the end of diastole (maximum ventricular volume). The pressure at this point is low, around 5-10 mmHg, and the volume is high, around 120-140 mL.

b. Draw a line from point A to point B, representing the isovolumetric contraction phase. During this phase, the ventricle contracts, but the volume remains constant. The pressure increases rapidly, reaching around 80 mmHg, reaching around 80 mmHg.

c. From point B, draw a line to point C, representing the ejection phase. During this phase, the ventricle continues to contract, and blood is ejected into the aorta. The pressure increases to a peak of around 120 mmHg, while the volume decreases to around 50-60 mL.

d. Draw a line from point C to point D, representing the isovolumetric relaxation phase. During this phase, the ventricle relaxes, but the volume remains constant. The pressure decreases rapidly, returning to around 5-10 mmHg.

e. Finally, draw a line from point D back to point A, representing the filling phase. During this phase, the ventricle fills with blood, and the volume increases back to its initial value.

3. Draw John's hypertensive pressure-volume loop:

a. Start at point A', which represents the end of diastole for John's heart. The pressure at this point is higher than in a healthy heart, around 15-20 mmHg, and the volume is similar, around 120-140 mL.

b. Draw a line from point A' to point B', representing the isovolumetric contraction phase. The pressure increases rapidly, reaching around 115 mmHg.

c. From point B', draw a line to point C', representing the ejection phase. The pressure increases to a peak of 185 mmHg, while the volume decreases to around 50-60 mL.

d. Draw a line from point C' to point D', representing the isovolumetric relaxation phase. The pressure decreases rapidly, returning to around 15-20 mmHg.

e. Finally, draw a line from point D' back to point A', representing the filling phase.

Comparing the two loops, you can see that John's hypertensive heart has a higher pressure throughout the cardiac cycle. This increased pressure can put extra strain on the heart and blood vessels, potentially leading to complications if left untreated.