1. Blood Vessel Physiology

2. Special Circulations Arterial supply of brain Brain must have oxygen
No oxygen brain cells die and cannot be regenerated
2 pairs of arteries supply brain
Internal carotid
Divides into cerebral arteries that supply cerebrum
Vertebral arteries
From subclavian arteries at base of neck
Forms basilar artery under skill
Supplies cerebellum and brain stem

3. Fetal Circulation Umbilical cord Hepatic Portal
Contains one large umbilical vein (carries oxygen) and 2 umbilical arteries
Fetal lungs are collapsed and non-functional
Closed off from circulation of fetus
Hepatic Portal
Detour of systemic arteries (mesenteric, splenic, gastric)
Allows liver to process or store nutrients

4. Arterial Pulse & Blood Pressure
Good indication of circulatory system health
Vital signs BP
Pulse
Temperature
Respiratory rate

5. Arterial Pulse Taking pulse rates
Arteries expand/shrink with heartbeat
Creates a wave through system
Pulse rate = heart rate
Taking pulse rates
Use pressure points
Most common area in wrist
Use first two fingers to feel pulse

6. Blood Pressure Closed system with pump = pressue
Closer to pump, higher the pressure
Pressure is exerted against walls of vessels
Keeps blood flowing
Follows a pressure gradient
High pressure to low pressure
Zero pressure by the time it reaches the venae cavae

7. Measuring Blood Pressure
Rise and fall with each beat
2 measurements are taken
Systolic
Peak of ventricular contraction
Diastolic
Ventricular relaxation
Written as a fraction
Systole on top
Most common site – brachial artery

8. Steps in Blood Pressure Measurement
Place the blood pressure cuff above the elbow
Place the bell of the stethoscope in the center of the inner elbow
Inflate the cuff by squeezing the bulb
Inflate until you cannot hear a beat with the stethoscope

9. Steps in Blood Pressure Measurement
SLOWLY begin to deflate the blood pressure cuff until you hear the FAINTEST beat.
This is the systole!
Keep deflating slowly until beats are no longer heard
This is the diastole!
Record results!