Cardiovascular Reflexes Flashcards
In the Vasomotor Center, what nerves are effected by PNS?
Vagal-cardiodepressor nerves
How does the PNS effect HR?
It decreases it
In the Vasomotor Center, what nerves are effected by SNS?
Cardioaccelerator nerves
How does the SNS effect HR?
It increases it
True or False? ANS has rapid short term control.
True
True or False? SNS is more important for circulation control than PNS.
True
True or False? PNS is more influence on cardiac system.
True
What are the effector organs of ANS cardiovascular reflexes?
cardiac, vascular, and kidneys
The ______ has continuous slow firing to maintain vasomotor tine.
SNS Vasconstrictor area
The _____ inhibits vasoconstrictor area.
SNS Vasodilator area
What other areas influence vasomotor control?
Hypothalamus Motor Frontal and Temporal Cortex Amygdala Cingulate
True or False? PNS affect HR only for practical purposes through Vagus nerve.
True
Through what mechanism is heart rate controlled?
SA Node
Through what mechanism is heart contractility controlled?
Ventricle Contraction
Through what mechanism is vascular resistance controlled?
Systemic Arterioles
Through what mechanism is vascular compliance controlled?
Systemic Veins
Through what mechanism is blood volume controlled?
kidneys
Chemoreceptors are loactde in the carotid and aortic bodies. They send afferent signals through _____ and _____ nerves..
Vagus and Glossopharyngeal
What are the four stimuli for chemoreceptors?
- hypoxemia: decrease in PaO2
- hypercapnia: increase in PaCO2
- acidosis: decrease in pH
True or False? Chemoreceptors have the same pathway as baroreceptors, but not as potent.
True
What happens when you have a decrease in blood flow to vasomotor center (CNS Ischemic Response)?
CNS hypercapnia
Rapid activation of SNS vasoconstrictor system
How does body respond to hypotension?
- decrease in afferent impulses via vagus and glossopharyngeal nerves in medulla, increase SNS efferent
- arterial constriction, increasing TPR
- vein vasoconstriction, increasing BV
- increase HR, increasing strength of contractility
- fluid retention by renal system
- increase respiratory rate
How does body respond to postural change?
- decrease in preload, decreasing BP
- increase SNS, decrease in PNS, vasconstriction
____ is failure to respond to postural change.
Cardiovascular incompetence
_____ causes venous pooling due to medication, pregnancy, ANS dysfunction, prolonged bed rest, cachexia.
Orthostatic Hypotension
_____ is temporary loss of consciousness.
(Vasovagal) Syncope
