Blood Pressure Flashcards
Blood Pressure
hydrostatic pressure exerted by blood
BP= Systolic pressure/
diastolic pressure
Systolic Pressure
maximum pressure in artery during ventricular systole
maximum pressure in arteries when ventricles contract
Diastolic Pressure
minimum pressure in artery during ventricular systole
minimum/lowest pressure in arteries when ventricles relax
Pulse Pressure
systolic pressure minus diastolic pressure
ex: 120-80= 40mmHg
Mean Arterial Pressure (MAP)
average pressure in artery
(average pressure in arterial system
Blood Pressures drop along the vascular system:
- Arterial System:
- highest pressure (120–>35mmHg) - Capillaries (35–>16mmHg)
- Venous System (16–> 0mmHg)
Normal range of Blood Pressure
BP= 120/80 (120 over 80)
Blood Pressure starts at:
starts at elastic arteries–>muscular arteries–> arterioles
-this is the arterial system (highest pressure system)
(120–>35mmHg)
Pressure across Arterial System:
120–>35mmHg
Pressure across Capillaries:
35–>16mmHg
Pressure across Venous System:
16–>0mmHg
Venous return of blood is aided by:
- Valves in veins (prevent backflow)
- Muscular Pump
- Respiratory Pump
Regulation of Blood Pressure (BP): Neural Regulation
-short-term regulation
neural regulation by cardiovascular center in the medulla oblongata:
A. Increase BP:
-Sympathetic increases Heart Rate (HR) + contractility
-Sympathetic causes vasoconstriction
B. Decrease BP:
- Parasympathetic decreases HR; which lowers BP
- Sympathetic causes vasodilation
(only the sympathetic division controls blood vessel diameter)
Cardiovascular centers located in
Medulla Oblongata
Neural regulation of BP by negative feedback mechanisms; sensors
- Baroreceptors- pressure sensors located in aortic arch and carotid arteries
- Chemoreceptors- chemical sensors (blood pH, oxygen, carbon dioxide) located in aortic arch and carotid arteries
- decrease O2 (extremely low O2) will trigger a chemoreceptor response
- decrease pH, increase CO2 (more CO2, the lower the pH)
Baroreceptors
pressure sensors located in aortic arch and carotid arteries
Chemoreceptors
chemical sensors (blood pH, oxygen, carbon dioxide) located in aortic arch and carotid arteries
- decrease O2 (extremely low O2) will trigger a chemoreceptor response
- decrease pH, increase CO2 (more CO2, the lower the pH)
Hormonal Regulation of BP:
-Short-term regulation Hormones that raise BP: 1. Angiotensin II (2) 2. Epinephrine 3. Norepinephrine 4. ADH (antidiuretic hormone)
Hormones that lowers BP:
1. Atrial Natriuretic Peptide (ANP)
Regulation by Kidneys
-long-term regulation
-kidneys adjusting blood volume
A. Increases BP(blood pressure):
-increase blood volume
B. Decrease BP(blood pressure):
-decrease blood volume