Lesson 2C Flashcards
What influences blood flow
Cardiac functino Vessel compliance Peripheral resistance Tone of vascular musculature Blood viscosity Pattern of branching vessels and collaterals Vasoconstriction and vasodialation Excercise Autoregulation Respiration
What is vessel compliance
Ability to expand and contract with pressure changes
What is peripheral resistance
Ability of arteries to constrict
Resistance increases with contraction
Tone of vasculature muscle is
Degree of restriction relative to maximal dialated state
What is blood viscosity
Thickness of blood
What is autoregulation
Constant blood flow to places that need it such as the brain and the renals
Arterial physiology depends on the
Cardiac status
Blood flow is determined by (2)
Blood pressure
Peripheral vascular resistance
Valvular dysfunction is
Prolapsed, vegetations, regurgitation
What is a heart beat
Rhythmic contraction of the heart
What is the heart rate
The number of times that the heart contracts per minute
What internal pacemaker
Sino-atrial and atrio-ventricular nodes that initiates the hearts own impulses to contract
Produces regular rhythm
The heart rate is controlled by the
Autonomic nervous system which regulates below the level of conciousness
The heart rate has both a ____ and ______ component
Sympathetic and parasympathetic component
Both the sympathetic and parasympathetic component have thier highest control center in the
Brain
What does the sympathetic nervous system do to the heart
Increases heart rate and force of cardiac contraction
What does the parasympathetic nervous system do to the heart
Reduce the heart rate and force of contraction
An increased heart rate yeilds
An increased volume of blood to the tissues
In order for fluid in a closed system to move from one point to another
An energy gradient must exist
In the case of the arterial tree, blood moves because of a
Pressure gradient
In the heart the ____ side is higher presuure and the right side is ______
This creates
Higher
Lower pressure
This creates the necessary pressure gradient
What is blood pressure
Force exerted by the blood against the arterial walls when the heart contracts
Blood pressure is an important indicator of
Current cardiovascular function and a risk indicator of future cardiovascular morbidity and mortality
