Cardiovascular Flashcards
What is cardiac output
volume of blood ejected per minute
How do you calculate cardiac output
HR x SV
What three factors regulate stroke volume
Degree of stretch on heart muscles prior to contraction (aka Frank Starling law)
Forcefulness of contraction
Pressure required to eject blood from ventricles
What is the sympathetic nervous system
Excitory - increased force of cardiac contraction
What is the parasympathetic nervous system
inhibitory - decreases force of cardiac contraction
Where are baroreceptors located
carotid sinus, arch of aorta
what factors influence heart rate
age
gender
physical fitness
body temperature
What is the function of the Cardiovascular centre
system in medulla oblongata that regulates heart rate and stroke volume
can also control neural and hormonal outputs involved with BP and blood flow to specific tissues
What is the function of the vaso motor center
regulates BP
What systems provide input to the cardio vascular center
higher brain centers - cerebral cortex, limbic system, hypothalamus
proprioceptors - monitor joint movements
chemoreceptors - monitor blood acidity (H+) CO2, 02
baroreceptors - monitor BP
What systems respond to output
Heart decreases rate - Vagus nerve (parasympathetic)
Heart increases rate - Cardiac accelerator nerve (sympathetic)
Vasoconstriction - vasomotor nerves
