1. Labs 33A
Circulation

2. Lab Pressures in the Systemic Circuit
Systolic pressure:
peak arterial pressure during ventricular systole
Diastolic pressure:
minimum arterial pressure during diastole
Pulse pressure:
difference between systolic pressure and diastolic pressure
Mean arterial pressure (MAP):
MAP = diastolic pressure + 1/3 pulse pressure

3. Measuring blood pressure
Enclose arm in cuff
Inflate to 160+ mmHg
Slowly allow pressure out while watching needle and listening to brachial artery with stethoscope
Watch and listen for the point where blood starts to flow through the cuff to the arm – this is the max pressure or systolic
Continue slowly letting pressure out until the point where you no longer hear the sound of turbulent blood flow (and needle stops bouncing) this is the point at which blood can flow freely meaning the pressure in cuff is just below minimum pressure or diastolic

4. MAP
MAP is considered to be the perfusion pressure seen by organs in the body
MAP of 60 is necessary to perfuse the tissues
Formula is an estimate
Diastole counts for 2/3 of MAP because 2/3 of cardiac cycle is spent in diastole (and 1/3 in systole)
At high HR, this difference decreases and a better estimate is actually just the average of systole and diastolic

5. Lab #37 Follow instructions on lab handout and enter your data there
Part 1 – auscultation
Part 2 – blood pressure:
At rest
Lying down
After exercise
Part 3 – measure pulse at three different locations

6. When done
We’ll put up the values on the board and look at the variation

7. Assignment Work in groups of 2 (3 max)
Lab guide filled out with data for yourself
Review Sheet Lab 33A- numbers 1 - 7, , , 24, 25, and 27 – 30
Due next Thursday