1. Important Concepts Associated with the Measurement of Blood Pressure

2. Blood Pressure (BP) Force exerted by circulating blood on the walls of blood vessels

3. Force exerted against walls of blood vessels when the heart contracts (systole) Systolic Blood Pressure

4. Force exerted against walls of blood vessels when the heart relaxes (diastole) Diastolic Blood Pressure

5. BP is one of the principal vital signs

6. BP Classification Systolic/Diastolic Values Normal 119/79 or less Prehypertension 120/80 to 139/89 Stage 1 Hypertension 140/90 to 159/99 Stage 2 Hypertension 160/100 or higher Classification of hypertension (elevated blood pressure) in adults Classification of hypertension (elevated blood pressure) in adults

7. Average blood pressure or mean arterial pressure (MAP) is determined by obtaining both systolic and diastolic values (point of this exercise)

8. Heart Rate (HR) Number of beats per minute

9. Stroke Volume (SV) Volume of blood pumped out by a ventricle with each heart beat

10. Graph showing the change in volume (mL) of blood in one “chamber” during a heart beat What is the volume of blood at the end of diastole? diastole systole EDV

11. Graph showing the change in volume (mL) of blood during one heart beat What is the volume of blood at the end of systole? diastole systole ESV

12. Graph showing the change in volume (mL) of blood during one heart beat Therefore, what is the stroke volume? diastole systole SV

13. Cardiac Output (CO) Volume of blood (mL) pumped by each ventricle in one minute (min)

14. Cardiac Output (CO) is Heart Rate (HR) x Stroke Volume (SV)

15. Example: What would be the cardiac output of an individual at rest (60 beats/min) and with no obvious heart condition (with the stroke volume already given)? Answer: CO (mL/min) = HR (60 beats/min)  SV (70 mL/beat) = 4,200 mL/min or 4.20 L/min

16. This means that over the course of one hour, one heart chamber at rest could eject over 240 liters of blood. That’s over 63 gallons! Sixty-three gallons for a little over six and a half days … this could fill a 10,000 gallon (small size) swimming pool. With continuous exercise (120 beats per minute), that time could be cut in about half (3 days)! * 1 Liter = 0.264172051 US Gallons

17. Where does your blood pressure fall?

18. Measuring Blood Pressure (BP) Interactive Physiology Exercise (In order to make this work, an access code log-in to myA&Pplace is required.) Steps: Click on Tutorials > Interactive Physiology > Chapter 19 > Cardiovascular System > Measuring Blood Pressure (complete all steps and the quizzes/worksheets) Click Here