Activity 1 – Pressure and volume

1. Indicate whether pressure increase or decrease in each of the situation given below.

a) Contraction of ventricles                 __________________________

b) Atrial diastole                                    __________________________

c) Atrial systole                                       __________________________

d) Ventricular diastole                          __________________________

e) Isovolumetric contraction               __________________________

f) Isovolumetric relaxation                   __________________________

2. Indicate whether volume increase, decrease or no change in each of the following situation given below.

a) Atrial contraction                           __________________________

b) Atrial diastole                                 __________________________

c) Ventricular systole                         __________________________

d) Ventricular diastole                       __________________________

e) Ventricular filling                            __________________________

f) Ventricular ejection                         __________________________

g) Ventricular relaxation                    __________________________

h) Isovolumetric contraction             __________________________

i) Isovolumetric relaxation                 __________________________

3. Outline the phases of the cardiac cycle. For each phase give the major event taking place.

4. Indicate what is taking place in each of the following

1.                                                           A.
2.                                                           B.
3.                                                           C.
4.                                                           D.
5.                                                           E.
6.                                                           F.

 

Activity 2 – Pulse measurement

1. Identify the radial pulse and while sitting determine pulse rate.

2. Count the number of pulses in 10, 20, 30 seconds. Multiply by the following; Number in 10 sec x 6, number in 20 sec x 3, number in 30 sec x 2.

a. What is your heart rate?

b. 10 sec

c. 20 sec

d. 30 sec

e. Which of the times is least accurate? ________________________

3. Stand for one minute and repeat the above while still standing. Record your measurements below. Calculate like you did above.

a. 10 sec

b. 20 sec

c. 30 sec

d. How did the BP change from sitting to standing? Explain what contributed to this change.

4. Identify your brachial artery? Between the brachial and the radial artery, which one is easier to take your pulse? Why?

Activity 3 – Blood pressure measurement.
Measurement of Blood Pressure
Blood pressure is measured using sphygmomanometer and a stethoscope. The sphygmomanometer includes an inflatable cuff which goes around the arm. When it is inflated using the inflation bulb, the brachial artery is squeezed preventing blood from going through. The cuff is then deflated listening for the different heart sounds or Korotkoff sounds.

 

Procedure for BP measurement

1. Wrap the cuff of the sphygmomanometer’s around the arm of the individual. Be sure to place the artery position marking at the area indicated. The cuff should not be too tight. Two fingers should be able to pass through freely.

2. Placed the stethoscope at the antecubital fossa and keep in place with one or two fingers.

3. Inflate the cuff using the inflation bulb, to the point when blood flow through the brachial artery stops and there is no heart sound or Korotkoff sounds. Usually 160 mmHg should be ideal.

4. While looking at the gauge, deflated the cuff slowly by pressing or turning the air release valve. When the first heart sound or Korotkoff sound is heard it is recorded as the systolic reading.

5. Continue deflating the cuff until blood freely flows through the artery and no sound is heard, marking the diastolic reading.

Questions

1. What is the diaphragm of the stethoscope used for?

2. Where must the diaphragm be placed to get good sounds?

 

3. Why should the air be released gradually?

 

4. Describe the change in Korotkoff sounds from systolic reading to diastolic reading.

 

Activity 4 – Effect of exercise on BP

Everyone must take turn measuring each other’s blood pressure (manually). Use the LabQuest device for this exercise.

1. Select a test subject. Take the baseline BP with the subject sitting in place and arm to be used for measurement placed freely on the bench. The arm should be place at heart level.

2. Wait about 2 minutes then take the subjects BP reading while standing.

a. Are there differences in measurement between sitting and standing? Give a short explanation for any differences seen.

3. Have the subject exercise (exercise to increase heart rate) for 3- 5 minutes.

4. Immediately following the exercise measure the BP.

5. Wait 5 minutes and take another reading.

6. Wait another 5 minutes and take the third and final reading.

7. Repeat step 6.

Questions

1. Draw a graph to show your results. Use time vs BP. Place Time on X axis and BP on the Y axis.

 

 

 

 

 

2. Describe the change in BP from baseline to 15 min after exercise.

 

3. Give an explanation for the change observed.

 

 

4. Describe the change in HR.

 

5. Give explanation of the change observed in HR.