Regulation of Cardiac Output and Blood Pressure

Question 1

Preload can become raised due to

Answer 1

Fast filling time and increased venous return

Question 2

Contractility can become raised due to

Answer 2

Sympathetic stimulation
Epi and norepi
high intracellular calcium ions
high blood calcium levels
thyroid hormones
glucagon

Question 3

Afterload can become raised due to

Answer 3

Increased vascular resistance
Semilunar valve drainage

Question 4

Preload can be decreased due to

Answer 4

decreased thyroid hormones
decreased calcium ions
high or low potassium ions
high or low sodium
low body temperature
hypoxia
abnormal pH balance
drugs

Question 5

Contractility can become lowered due to

Answer 5

Parasympathetic stimulation
acetylcholine
hypoxia
hyperkalemia

Question 6

Afterload can become lowered due to

Answer 6

Decreased vascular resistance

Question 7

What factors affect heart rate?

Answer 7

Increase (Positive chronotrope)-
Sympathetic input
Hormones, such as thyroid hormone

Decrease (Negative chronotrope)-
Parasympathetic input

Question 8

Total Peripheral Resistance is a product of these three factors

Answer 8

Blood viscosity
Total blood vessel length
Vessel diameter (main factor)

Question 9

The amount of blood ejected by each ventricle in 1 minute is

Answer 9

Cardiac output

Question 10

Equation(s) for CO

Answer 10

CO = HR x SV
CO = BP / TPR

Question 11

There are four main factors that affect the CO

Answer 11

Heart Rate
Contractility
Preload
Afterload

Question 12

Equation for Blood pressure

Answer 12

BP = CO x TPR

Question 13

The SA node is the _____ mechanism for controlling CO.

Answer 13

Intrinsic

Question 14

Neural control of CO and BP (extrinsic)

Answer 14

Rapid: Neural control of vessel diameter, heart rate, stroke volume

Question 15

Chemical/hormone control of CO and BP (extrinsic)

Answer 15

Intermediate to long-term:
Renin-Angiotensin II system
Renin-Aldosterone system
Antidiuretic Hormone (ADH)

Question 16

Three areas of the vasomotor center (neural control)

Answer 16

Vasoconstrictor
Vasodilator
Sensory

Question 17

Vasoconstrictor Area- Neurons originating here extend down the spinal cord and ____

Answer 17

excite preganglionic sympathetic fibers.

Question 18

The Sensory Area is Located in the ___

Answer 18

Nucleus of Tractus Solitarius

Question 19

When needed, the lateral portions of the Vasomotor center transmit _____ to increase heart rate and contractility

Answer 19

excitatory impulses through the sympathetic nerve fibers

Question 20

Through the Autonomic Nervous System, the Vasomotor Center regulates these three things

Answer 20

HR, SV, and TPR

Question 21

Sensory info from ____ receptors enters the Nucleus of Tractus Solitarius from ___ and ___

Answer 21

Baroreceptors; Glossopharyngeal and vagus

Question 22

The rate of firing from the baroreceptors progressively ____ with increasing blood pressure

Answer 22

increases

Question 23

The Baroreceptor Reflex results in _____ by decreasing sympathetic outflow and increasing parasympathetic outflow from the CNS

Answer 23

decreased blood pressure

Question 24

When arterial blood pressure falls well below normal, these receptor cells are hypoperfused, resulting in low O2, elevated CO2, and elevated H+. Signals are transmitted via the glossopharyngeal and vagus nerves which excite the Vasomotor Center

Answer 24

Chemoreceptors

Question 25

Chemoreceptors increase BP due to

Answer 25

increased TPR and increased CO

Question 26

What is the CNS Ischemic Response?

Answer 26

Decreased blood flow due to hypotension results in increasing levels of CO2 and H+ in the medulla, This has a direct effect of stimulating the sympathetic fibers in the Vasomotor Center, resulting in an increase in blood pressure.

Question 27

In the RAA System, _____ in the walls of the Afferent Arterioles act as baroreceptors and respond to a drop in blood pressure by releasing Renin

Answer 27

Juxtaglomerular cells