2/27- Blood Pressure (Exam 2) Flashcards
What is preload?
Stretching affect of the left ventricle because blood was left that didn’t leave and then refilled and stretched left ventricle
What stretches the left ventricle and then what happens?
Sarcomeres
After stretched they come together harder to contract
What is the first difference between bainbridge reflex and frank starling?
Bainbridge- right atrium only
Frank- left ventricle only
What is the second difference between Bainbridge and frank starling?
Bainbridge- heart responds by beating faster
Frank- the contractions of heart are stronger
What is the last difference between Bainbridge and frank starling?
Bainbridge- reflex set off by stretch receptors
Frank- has to do with way sarcomeres are built
What is blood pressure?
Pressure of blood in the arteries of the systemic circuit (body)
What are the 4 factors that affect blood pressure?
1) cardiac output- CO up, pressure up
2) peripheral resistance
3) blood volume
4) blood viscosity
What are the 2 out of the 4 the body controls?
1) cardiac output
2) peripheral resistance
What is a lumen of a vessel?
The hollow interior
What is vasodilation?
Relax smooth muscle lumen will widen
Lowers blood pressure
What’s in the medulla oblongata for blood pressure?
Vasomotor center
What does the vasomotor center do?
Wired to blood vessels controlling the diameter
Autonomic innervation
Can command vasoconstriction
What connection do blood vessels have?
Sympathetic
What happens if you need vasodilation?
Vasomotor center cuts all ties of sympathetic connection and hopes the vessels dilate
What is blood volume?
More blood in vessels higher pressure
Less blood lower pressure
What can affect blood volume?
Hemorrhage- ant bleeding (decrease blood volume)
What do people with hypertension have to stay away from and why?
Salt
Needs water to dilute salt
Stays in blood vessels
Higher blood volume= higher blood pressure
What is viscosity and how is it in our bodies?
Ease with which a liquid will flow
Fairly stable
What is vasoconstriction?
Narrow diameter of lumen by contracting smooth muscle
Increases blood pressure
What happens if you have high viscosity?
Blood pressure raises
Harder to push through vessels so pressure goes up
What happens with low viscosity?
Blood pressure decreases
What are both cardiac control center and vasomotor center connected too?
Baroreceptors and chemoreceptors
What is the radial artery?
Used to get blood pressure by sticking a probe in it
What is the sphygmomanometer?
Blood pressure cuff
Used with stethoscope
Gets 2 readings-
1) left ventricle contracts (raise to max)
2) left ventricle relaxes (drops to min)
If blood pressure changes what control center gets notified?
Both
