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cardio phys
na
343
Physiology
Graduate
06/11/2010

Additional Physiology Flashcards

 


 

Cards

Term
What are the valves located on the left side of the heart?
Definition
mitral and aortic
Term
What are the valves on the right side of the heart?
Definition
tricuspid and pulmonic
Term
Which chamber are in the upper section of the heart?
Definition
atriums
Term
Which chambers are on the lower end of the heart?
Definition
ventricles
Term
What valve separates the right atrium and ventricle?
Definition
tricuspid valve
Term
What valve separates the left atrium and ventricle?
Definition
mitral valve
Term
What type of blood enters the right side of the heart?
Definition
de-oxygenated
Term
What type of blood enters the left side of the heart?
Definition
oxygenated
Term
Where do the pulmonary arteries send blood?
Definition
to be oxygenated by the lungs
Term
Where does oxygenated blood enter the heart?
Definition
pulmonary veins
Term
Where does the aorta pump blood?
Definition
into the body for organ oxygenation
Term
What component of the heart dumps deoxygenated blood back into the right atrium?
Definition
superior vena cava
Term
Are the right and left chambers of the heart independent or interdependent? 
Definition
interdependent because their chambers are connected in series
Term
Are malfunctions in the left side transmitted back into the pulmonary circulation and the right heart?
Definition

yes interdependent sides

-right outworks the left the pulmonary system overdoes and can drown in own fluids

Term
Where do malfunctions in the right heart affect other areas?
Definition

output of the left heart and imperil the blood supply to all systemic organs

-backs up into the superior and inferior vena cava

-left exceeds the right then person can bleed out

Term
How does the arterial system deliver blood to organ systems?
Definition
in parallel
Term
Are organ systems dependent on blood flow through another organ system?
Definition

not in most cases except for portal ciculation and the kidneys

-allows for adjustment of blood flow to meet ind organ needs without creating major disturbances in blood supply

Term
Can fluid move through a system without energy application?
Definition
no must have energy applied to it
Term

In the CV system energy is known as?

 

Definition

pressure 

-pressure gradient between two points in a system

Term
When does arterial pressure peak?
Definition
shortly after the heart contracts and pumps blood into aorta
Term
What is hemodynamic pressure?
Definition
produced by contractions of the heart and stored in the elastic walls of the blood vessels
Term
What is systolic pressure?
Definition
the peak arterial pressure during contraction of the heart
Term
What is diastolic pressure?
Definition
minimum arterial pressure during relaxation of the heart
Term
blood pressure =?
Definition
systolic BP/diastolic BP
Term
What is the inner layer of arteries and veins?
Definition

endothelium

-single layer of epithelial cells

Term
What is the middle layer of arteries and veins?
Definition

smooth muscle

-contraction and relaxation widen or reduce the lumen diameter

-arranged in circular layers

Term
What is the outer layer of arteries and veins?
Definition

adventitia

-composed of collagen and elastin fibers

Term
Volume contained within vessels is a function of?
Definition

-transmural pressure- difference in pressure inside v. outside a hollow structure

-degree of flexibility within vascular wall

Term
Do veins and arteries have large or small transmural pressures?
Definition

veins- large tmp creating very large intervascular volume and more flexible walls

arteries- small tmp more stiff walled and small intervascular changes

Term
What is the vascular capacitance?
Definition
volume of blood contained in the vessel for a given transmural pressure
Term
What is compliance?
Definition
change in volume for a given change in transmural pressure
Term
As transmural pressure increases, compliance increases or decreases?
Definition

decreases

-veins highly distendable and has higher compliance and capacitance compared to stiff vessels of the same size

Term
What is tension?
Definition

force that opposes the force within the vessel that keeps vessel from ripping apart

equal to the products of the transmural pressure and the vessel radius

 

Term
What is the relationship between vessel wall thickness and stress called?
Definition
Law of LaPlace
Term
Are small vessels able to withstand higher or lower pressure than vessels of larger diameters?
Definition
higher
Term
Will vessels with thick walls relative to their radius able to withstand higher or lower pressure than vessels with small radius/wall ratios? 
Definition

higher

-because wall stress is lower in thicker walls

Term
What is Poiseuille Law?
Definition

principle that the volume of a homogenous fluid passing per unit time through a capillary tube is

-directly proportional to the pressure difference between its ends and to the fourth power of its internal radius

-inversely proportional to its length and to the viscosity of the fluid

Term

Poiseuill Law

 

doubling the pressure ____the flow

Definition
doubles
Term

Poiseuille Law

 

halving the pressure______ the flow?

Definition
halves
Term

Poiseuille Law

 

doubling the length of the tube ___ the flow by _____

Definition
reduces by half
Term

Poiseuille Law

 

doubling the tube radius ______ flow by 16fold

Definition
increases
Term

Poiseuille Law

 

do thick sticky fluids flow more or less easily than a thinner watery-like fluid

Definition
less easily
Term
What is the formula for blood pressure?
Definition

BP= CO * TPR

cardiac output * total peripheral resistance

Term
What is atherosclerosis?
Definition
inflammatory response to vessel injury resulting in narrowing of the lumen increasing vascular resistance and diminishing blood flow
Term
What type of muscle composes the heart?
Definition

striated muscle

-doesn't require innervation to be activated

-muscle contraction coupled with action potential from within cells

Term
Cardiac cells have property of ____?
Definition

automaticity

-ability to generate their own action potential

Term
Cardiac cells demonstrate property of?
Definition

rhythmicity

-ability to generate action potentials in a regular repetitive manner

Term
Hear behaves as a?
Definition

functional syncytium

-as if it were one large cell

Term
What is an action potential?
Definition
momentary change in electrical potential on the surface of a cell that occurs when it is stimulated, resulting in the transmission of an electrical impulse
Term
What are the 3 electrophysiologic cells of the heart?
Definition

pacemaker

specialized rapidly conducting tissues (purkinje fibers)

ventricular and atrial muscle cells

Term
Which cells are fast response?
Definition

ventricular

atrial

purkinje

Term
Which cells are slow response?
Definition

sinoatrial (SA) node

atrioventricular (AV) node

Term
What is the resting potential?
Definition

in cardiac cells at rest, prior to excitation, the resting potential is the electrical charge differential b/w the inside and outside of cell

--90mV

Term
What is depolarization?
Definition

change in membrane potential cell interior becomes relatively less negative than the cell exterior

-transmitted from cell to cell creating a wave or impulse of electrical activity

Term
What is repolarization?
Definition

change in membrane potential returning to the initial resting (polarized) state

-cell interior becomes more - than cell exterior

Term
How many phases are in the action potential of cardiac cells?
Definition

5

0-4

Term
The resting state before depolarization is?
Definition

phase 4

-associated with diastole (at rest)

Term
What happens during phase 0?
Definition

-rapid depolarization phase

-rapid influx of NA+ into cell

-threshold potential of cardiac cells -70mV

have self sustaining inward Na+ current

membrane potential neutralizes to 0 and into positive range (Na influx)

Term
What happens in phase 1?
Definition

-transient outward K+ current responsible for partial repolarization

-returns membrane to 0mV

Term
What happens in phase 2?
Definition

-slow Ca++ influx and relatively low K+ efflux results in plateau

-maintains a voltage of approximately 0mV

-Ca++ channels slowly inactivate and efflux of K+ begins to exceed influx of Ca++

Term
What happens in phase 3?
Definition

-rapid repolarization

returns transmembrane voltage back to -90 mV

-largely results from K+ efflux

Term
Pacemaker cells have the property of ______ by which cells undergo _______ depolarization during phase 4?
Definition
automaticity, spontaneous
Term
Where is pacemaker behavior displayed?
Definition
SA and AV nodes
Term
Action potential in pacemaker cells is different than other cardiac cells how?
Definition

3 ways:

-max - voltage is -60mV

-phase 4 isn't flat but has an upward slope representing spontaneous gradual depolarization

-phase 0 upstroke is less rapid and reaches lower amplitude relying solely on Ca++ influx

Term
Can cardiac cells be tetanized?
Definition
no single contraction of cardiac muscle is completed before a second action potential can be generated
Term
Resting membrane is primarily a _____ diffusion potential
Definition

K+

-high plasma K+ hyperkalemia depolarize cardiac cells (cardiac arrest)

-low plasma K+ conc. hypokalemia hyperpolarizes the tissue

Term
What effect do catecholamines have on the heart?
Definition

-enhance Ca++ movements & increase size of action potential

-Norepi increases phase 3 K+ conductance shortening cardiac refractory period

Term
What effect do calcium channel blockers affect the heart?
Definition
depress Ca++ movement and result in small action potentials
Term
What node is the dominant pacemaker?
Definition

SA node, initiates an action potential

 

Term
Where is the SA node located?
Definition
posterior aspect of the right atrium
Term
What is the normal rate of the SA node?
Definition
60-100 bpm
Term
How fast does an action potential travel through both atria?
Definition
.1-1.0m/sec
Term
Where do impulses from the SA node coalesce?
Definition
AV node
Term
Where is the AV node located?
Definition
at the junction between the atria and ventricles
Term
What is the rate of conduction of the AV node?
Definition

.05m/sec (.1sec)

-important bc without delay the ventricles wouldn't have time to fill after diastole

 

Term
What is the only normal pathway between atria and ventricles?
Definition
AV node
Term
What is the bundle of His?
Definition

splits into left and right bundle branches

-bundle branches give rise to Purkinje fibers

Term
What lines the entire endocardial surface of the ventricles?
Definition

purkinje fibers

 

Term
How fast do purkinje action potentials travel?
Definition
4cm/sec
Term
What order do the signals flow in purkinje fibers?
Definition
ventricles activated from septum and endocardium to epicardium, and from apex to the base of the heart
Term
If a pace in the SA node <60 bpm?
Definition
sinus bradycardia
Term
If pace in the SA node > 100 bpm?
Definition
sinus tachycardia
Term
If the SA node fails what are the 3 other potential pacemakers?
Definition

atria- 60-80 bpm

AV junction- 40-60 bpm

ventricles- 20-40 bpm

 

Term
What is overdrive suppression?
Definition
SA node suppresses all other potential pacemaker sights when functioning properly so the sights aren't fighting for control
Term
What is an electrocardiogram (ECG or EKG)
Definition

amplified, timed recording of the electrical activity of the heart

-detected from the surface of the body

-plot of voltage as a function of time

Term
What can an EKG detect?
Definition

-heart rhythm abnormalities

-myocardial ischemia and infarction

-electrolyte inmalances

-effect of certain medications

-anatomic orientation of heart

-size of atria/ventricles

-path take by action potentials

 

Term
What can a EKG not detect?
Definition
direct information about the contractile performance of the heart
Term
In an EKG as the ______ wave of _____within myocytes flows toward a _____ electrode, there is a ______ upward deflection recorded on EKG
Definition
positive, depolarization, positive, positive
Term
What is the P wave caused by?
Definition
depolarization (contraction) of both atria (not just SA node)
Term
What makes up the QRS complex and what does it represent?
Definition

depolarization of both ventricles

represents the beginning of ventricular contraction

Term
What is the Q wave?
Definition
first downward deflection
Term
What is the R wave?
Definition
upward deflection
Term
What is the S wave?
Definition
downward deflection following R wave
Term
Is the Q wave always in the QR complex?
Definition
no
Term
What does the ST segment represent?
Definition

plateau phase of ventricular repolarization

-follows QRS complex

Term
What does the T wave represent?
Definition
final rapid phase of ventricular repolarization
Term
What is the PR interval?
Definition
time from the beginning of the P wave to the start of the QRS complex
Term
What does the PR interval represent?
Definition

amount of time the action potential takes to travel from SA node through the AV node

.12-.20 seconds

Term
What does the QRS interval represent?
Definition

interval of time action potential takes to travel from the end of the AV node through the ventricles

.06-1.0 sec

Term
When does ventricular systole begin and when does it persist until?
Definition
begins with QRS complex and persists until end of the T wave
Term
What does the QT interval represent?
Definition
duration of the ventricular systole 
Term
When does the QT interval begin and end?
Definition
begins at QRS until the end of the T wave
Term
What is the measure of the smallest square in EKG paper?
Definition
1 mm
Term
Between the heavy lines there are 5 small squares equalling?
Definition
5 mm long
Term
The horizontal axis on an EKG represents?
Definition

time

.04 seconds in each small box

distance between 2 heavy boxes is .2 seconds

Term
How many leads make up an EKG?
Definition

12

-6 limb and 6 chest

Term
Where are the leads placed?
Definition
right and left arm and left leg
Term
How are the bipolar limb leads placed?
Definition

-lead I (-) right arm (+) left arm

-lead II (-) right arm (+) foot

-lead III (-) left arm (+) foot

Term
How are the augmented leads placed?
Definition

AVF- left foot +

AVR- right arm +

AVL- left arm +

Term
How are the chest leads placed?
Definition

V1-V6

successive steps from the patient's right to the left side of the chest

Term
V1 and V2 placed over?
Definition
right ventricle
Term
V3 and V4 placed over?
Definition
interventricular septum
Term
V5 and V6 placed over?
Definition
left ventricle
Term
True/False: the heart is a single sustained fused contraction?
Definition

true

-allcells that can contract during a single activation do so; there are no spare units to recruit

Term
What is a major determinant of the force of cardia conc.?
Definition

conc. of Ca++

-increased Ca++ conc. enhances contractile force

-decreased Ca++ conc reduces contractile force

Term
Do catecholamines enhance or decrease Ca++ fluxes and force of ventricular contractions?
Definition
enhance and strengthen force of contraction
Term
The tricuspid and mitral valves are?
Definition
atriventricular valves
Term
The aortic and pulmonic valves are?
Definition
semilunar valves
Term
What does the first heart sounds signal?
Definition
closure of atrioventricular valves
Term
What does the second heart sound represent?
Definition
closure of the aortic and pulmonic valves
Term
When is the only time the opening of the valves can be heard?
Definition
if they are damaged
Term
What is the term for the atrioventricular valve narrowing?
Definition
opening snap
Term
What is the term for the narrowing of the semilunar valve?
Definition
ejection click
Term
As systole begins, ventricular contraction _____ the pressure in the ventricles and _______ the pressure in the left atrium which forces the ______valve closed preventing backflow.
Definition

raises; exceeds; mitral

(S1)

Term
As the ventricle contracts, there is a period of time when the intraventricular pressure______the left ______ pressure, but is still less than the ______ pressure. This is called?
Definition

exceeds; atrium; aortic

isovolumic contraction

Term

Interventricluar pressure rised until it exceeds that in the aorta.

_____ and ______ valves are forced open and ejection of blood in ____begins.

Definition
aortic; pulmonic; arteries
Term
What is the rapid ejection phase?
Definition
70% of ejected volume exits the ventricle during the first third of the ejection
Term
What is the reduced ejection phase?
Definition
rate at which blood exits the ventricle begins to decline
Term
What is isovolumic relaxation?
Definition
early in ventricular relaxation the aortic and mitral valves are closed and the ventricle relaxes isovolumetrically
Term
What are the 2 components of the second heart sound?
Definition

A2- produced by aortic valve closure

P2- produced by pulmonic valve closure

Term
As the ventricular pressure falls below atrial pressure the ______ and _____ valves open to allow the blood collected in the _____to refill the relaxed _____.
Definition
mitral; tricuspid; atria; ventricles
Term
During diastole, pressure in the blood-filled ___ slightly exceeds that in the relaxed ___
Definition
LA; LV
Term
Blood flows from the LA to LV across open ____?
Definition
mitral valve
Term
Just before the onset of ventricluar systole, ____ contraction produces a slight pressure rise in both chambers- _____
Definition
artrial; artrial kick
Term
During systole, ____ starts to contract and ____ pressure rapidly exceeds ____ pressure and ____closes
Definition
LV; ventrical; LA; mitral valve
Term
Closure of the MV produces?
Definition
first heart sound
Term
LV pressure continues to rise and quickly ___ the pressure in the ___ and forces the ____valve to open.
Definition
exceeds; aorta; aortic
Term
Normally maximal LV pressure corresponds to ____blood pressure 
Definition
systolic
Term
As the ___ejects most of its blood, ____pressure begins to fall?
Definition
LV; ventricular
Term
When LV pressure drops below aortic pressure the ____ closes
Definition
AV
Term
What does closure of the AV produce?
Definition
second heart sound
Term
In diastole, ____pressure continues to drop and falls below ____ pressure
Definition
LV; LA
Term
When LV pressure falls below LA pressure the _____ opens and might hear?
Definition
MV; opening snap
Term
After the MV opens, rapid ____filling from the ____ occurs
Definition
ventricular; LA
Term
In what population might you hear a third heart sound?
Definition

children or young adults from rapid deceleration of the column of blood against ventricular wall

-pathologic in older adults indicates change in ventricular compliance

Term
What does the 4th heart sound mark?
Definition

atrial contraction or pathologic change in ventricular compliance

-always pathologic

Term
The pressure in the RV, RA, and pulmonary artery are _____ than those on the left side of the heart.
Definition
lower
Term
Do the same events occur on the right side of the heart and are they exactly the same?
Definition
same events occur but slightly later on the right side
Term
What are the four factors that influence contractile strength of cardia muscle?
Definition

1) preload

2) afterload

3) contractility (inotropic state)

4) inotropic effect )of increased heart rate)

Term
Cardiac output is equal to?
Definition

product of stroke volume and the heart rate

CO= SV * HR

Term
Increase in contractility increases or decreases stroke volume?
Definition
increases
Term

Increase in preload increases or decreases stroke volume?

Definition
increases
Term

Increase in afterload increases or decreases stroke volume?

Definition
decreases
Term

Increase in heart rate increases or decreases cardiac output?

Definition
increases
Term

Increase in stroke volume increases or decreases cardiac output?

Definition
increases
Term
What is preload?
Definition
-initial length to which the muscle is stretched prior to contraction
Term
What happens during preload?
Definition

passive stretch is proportional to the amount of filling (volume) of the heart during diastole

-increased filling increases the potential isometric contractile force that can be generated in the heart

Term
What is afterload?
Definition
the force against which cardiac muscle must contract to generate pressure and shorted
Term
What is contractility?
Definition

accounts for changes in the force generated by the myocardium for a given set of preload and afterlad

-change in contractility moves curve up or down (Frank-starling curve)

Term
What is the Frank-starling law?
Definition

the mores the ventricle is filled with blood during diastole the greater the volume of ejected blood will be during the resulting systolic contraction

"more heart fill, more it pumps"

Term
What is heart failure?
Definition

heart unable to maintain sufficient output to meet body's normal metabolic needs

 

Term
What are the results of heart failure?
Definition
deterioration of the heart muscle or worsening of the contributing factors external to the heart
Term
What are weakened heart muscles (reduced contractility)
Definition

load presented to weakened heart is too high for muscle, therefore, muscle can't shorten as far and with normal velocity

-stroke volume and cardiac output reduced because of inability of heart to pump blood

Term
increased ventricular volumes and wall stress during contraction increases?
Definition
afterload on heart
Term
_____ further declines bc of combined weakened condition and increased afterload due to heart failure
Definition
stroke volume
Term
True/false: Diastolic heart failure may or may not accompany systolic failure
Definition
true
Term
What is impaired relaxation?
Definition

muscle resistant to stretch that must take place during diastole

-muscle can't sufficiently lengthen, begins its contraction at too short a length

-muscle unable to shorten sufficiently to pump an adequate volume of blood with each beat

Term
Which part of circulation are nutrients, water, gases, hormones, and waster products exchanged between blood and cells?
Definition
microcirculation
Term
What is the smallest vein?
Definition
venule
Term
What is the smallest artery?
Definition
arteriole
Term
Where does the actual exchange in the microvasculature take place?
Definition
capillary beds
Term
Do large arteries have a high or low resistance to blood flow?
Definition
low
Term

Small arteries and arterioles together regulate what percent of total vascular reistance?

Where is the remainder equally divided?

Definition

70-80

between capillaries and venules

Term
As vessel size decreases does the resistance increases or decrease?
Definition
 increases
Term
What supplies the capillaries and where is the outflow collected?
Definition
terminal areterioles; postcapillary venules
Term
Do capillaries contain smooth muscle?
Definition
no they have the pericyte which is primitive capillary smooth muscle
Term
What type of cell are capillaries composed of?
Definition
endothelial
Term
What type of molecules readily pass through lipid components of endothelial cell membranes in capillary?
Definition
lipid-soluble (O2 & CO2)
Term
Where must water soluble molecules diffuse to enter the capillary?
Definition
through water filled pathways called pores
Term
Is porosity of capillaries the same in all organs?
Definition
no
Term

What type of capillary junction are found in the brain and the spinal cord?

What type of molecules may pass?

Definition

tight

smallest water soluble 

Term
Capillaries in _____ and ____ muscle have relatively low porosity to water and small water soluble molecules?
Definition
cardiac and skeletal
Term

Capillaries in intestines, liver, and glomerulus of kidney have capacities for larger/small water transport?

 

Definition
large
Term
Where are the largest capillary pores located?
Definition
spleen and bone marrow
Term
Venules collect blood from capillaries and act as a?
Definition
blood reservoir
Term
Are venules more/less permeable than capillaries to large and small molecules?
Definition
more
Term

At rest is there more blood volume in the arteries or veins? 

Where is most of the at rest blood located?

Definition

veins

1/2 of which is within the venules

Term
What forms an interconnected system of simple endothelial tubes within tissues?
Definition
lymphatic vessels
Term
What does the lymph system carry?
Definition
transport fluid, serum proteins, lipids, and foreign substances from interstitial spaces back to the circulation
Term
What organs have the most extensive lymph system?
Definition

GI tract, liver and skin

pulmonary circualtion

Term
Is movement of fluid from tissue to the lymph system passive or active?
Definition
passive
Term

When compressed or actively contracted the lymph vessels are allowed to?

Why?

Definition

passively relax

pressure in the lumen becomes slightly lower than in the interstitial space and tissue fluid enters the lymph vessel

 

Term
When the lymphatic bulb or vessel again contracts (compressed), after initial relaxation, overlapped cells are?
Definition
sealed to hold lymph 
Term
The pressure developed inside the lymph vessel forced the lymph?
Definition
downstream to the next segment of the lymph system
Term
Is the lymph system constantly moving?
Definition
no there must be pressure (contraction and relaxation) to cause movement
Term
When there is excess water in the lymph vessels, the compression/relaxation increases/decreases in frequency and vigor?
Definition
increases
Term
What system does the lymph system run with?
Definition
veinous
Term

Are lymphatic valves one-way?

Why or why not?

Definition

one-way

allow lymph to flow only from the tissue toward the progressively larger lymphatic vessels and finally into large veins in the chest cavity

Term
Exchange between interstitial fluid and capillaries occurs via?
Definition

diffusion

filtration

vesicular transport

Term
Why is spacing in the microvasculature important?
Definition

the more capillaries spaced out around the cell the more exchange takes place and increases the rate of diffusion

-especially important because becomes impaired in many disease state- diabetes, atherosclerosis

Term

transport only limited by the RATE of delivery into the capillaries from blood flow perfusing the capillary network

 

Definition
flow limited transport
Term
Large molecules (protein, sucrose) have difficulty diffusing across capillary pores and thus diffusion is rate limiting
Definition
diffusion-limited transport
Term
Diffusion is ____related to the distance with which it has to travel?
Definition
inversely
Term

_____favors the pressurized filtration of water through pores?

Why?

Definition

hydrostatic pressure

hydrostatic pressure on the blood side is higher than on the tissue side

Term
What is the primary defense against excessive fluid filtration from the capillaries?
Definition
colloid osmotic pressure
Term

What does the colloid osmotic pressure provide?

Where is the pressure generated by?

Does it act with or opposite the hydrostatic pressure?

 

Definition

provides force pulling water into capillaries

pressure generated by plasma proteins

opposite

Term
What is the major protein contributing the capillary oncotic pressure?
Definition
serum albumin
Term
Is there a slightly +/- overall force for filtration of fluid out of the capillaries?
Definition
+
Term

When does edema occur?

When does dehydration occur?

Definition

-interstitial fluid volume exceeded hydrostatic pressure elevated hydrostatic pressure goes to tissues

-negative hydrostatic tissue pressure water loss from tissues

Term
What is the plasma protein circulating value largely determined by?
Definition
the rate of protein synthesis in the liver
Term
What is edema?
Definition
excessive accumulation of fluid in tissue spaces
Term
What is ascites?
Definition
edema formation in the abdominal cavity
Term

Does edema increase/decrease diffusion distances? 

 

Definition
increasing
Term

  • Loss of protein from the plasma will result in?

What are some causes of this?

Definition

  • edema
  • liver disease- production issue, kidney-excessive loss of protein disease, burns, and hives- destruction of the capillary integrity increase in amount of protein coming through
  • obstruction

-veins: increase in pressure on venous side forces back increases interstitial fluid (DVT)

-lymph channels: fluid not going back to lymph system instead remaining in interstitial space

Term

What is released from all arteries, microvessels, veins, and lymphatic endothelial cells?

Why is it important?

Definition

endothelium-derived relaxing factor (EDRF)

important contributors to local vascular regulation

Term
EDRF is _____?
Definition
NO
Term
What causes relaxation of vascular smooth muscle?
Definition

NO

causes vasodilitation

Term
What causes the release of NO?
Definition

acetylcholine

histamine

ATP & ADP

hypoxia

adenosine

Term
What is the potent vasoconstricor of blood vessels released by endothelial cells?
Definition
endothelin
Term
What chemical plays a large role in vascular disease? (HTN, atherosclerosis, diabetes)
Definition
endothelin
Term
Loss of NO causes vasculature to become?
Definition

prospasmodic: spasm of the arteries constricting it down decreasing blood flow

prothrombotic: risk of clots

proatherogenic: risk of atherosclerosis lipid collection in the vessel 

Term
The maximum pressure your heart exerts while beating
Definition
systolic arterial pressure
Term
Amount of pressure in you arteries between beats
Definition
diastolic arterial pressure
Term
What is a normal BP?
Definition
120/80
Term
What are the four principal pressures contained within the arterial pressure waveform
Definition

mean arterial pressure

systolic arterial pressure

diastolic arterial pressure

pulse pressure

Term
The area under the pressure curve divided by the time interval
Definition
mean arterial pressure
Term

The difference between the maximum and minimum blood pressures produced during one heart beat.

What does this represent?

Definition

pulse pressure

represents the force that heart generates each time it contracts

Term
How is the mean mean pressure measured?
Definition

diastolic pressure + 1/3 (pulse pressure)

ex.

BP 120/80

pulse pressure 40mmHg

80+ 1/3(40)= 93

Term
What is the most important cause of elevated pulse pressure?
Definition

stiffness and reduced elasticity of the aorta

-HTN, atherosclerosis, sever anemia, hyperthyroidism

Term
What is the formula for BP and cardiac output?
Definition

BP=CO * SVR

CO= HR * SV (contractility, preload, afterload)

Term
The small arteries, arterioles, and capillaries account for how much of the vascular resistance?
Definition
90%
Term
What the the 2 ways arterial pressure can be measured?
Definition
direct or indirect
Term
What uses an inflatable cuff wrapped around the patient's arm?
Definition
sphygmomanometer
Term
The blood spurts past the point of partial occulsion at high velocity, resulting in turbulence- audible vibrations known as?
Definition
korotkoff sounds
Term

The pressure corresponding to 1st korotkoff sound is?

Pressure at which the korotkoff sounds cease is?

Definition

-systolic pressure

-diastolic pressure

Term
A cuff that is too narrow will give a?
Definition
falsely high pressure
Term
What factors affect arterial pressure?
Definition

age

race

diet

gender

body weight

Term
elevated arterial pressure defined as BP is?
Definition
>140/90 mmHg
Term
Small changes in venous pressure are associated with _____changes in venous volume?
Definition

large

-systemic veins  20 times more compliant than systemic arteries

Term
Blood in the superior vena cava and intrathoracic portions of the inferior vena cava, right atrium, right ventricle, pulmonary circulation, and left atrium make up the?
Definition

central blood volume

-constitutes 25% of total blood volume

Term
Most important components include veins of extremities and abdominal cavity.
Definition

extrathoracic blood volume

 

Term
The pressure of blood in the central venous system, where the superior and inferio vena cava meet just prior to entry into the right atrium
Definition
central venous pressure
Term

Changes in central venous pressure at a good reflection of?

Is this an invasive to measure? 

Definition

central blood volume

yes measured by placing the tip of a  catheter in the right atrium

Term
Central venous pressure is elevated by?
Definition

-overhydration which increases venous return

-heart failure which limit venous outflow and leads to venous congestion

-positive pressure breathing, straining

 

Term
Central venous pressure decreases with?
Definition

-hypovolemic shock from hemorrhage, fluid shift, dehydration

-negative pressure breathing which occurs sometimes with spinal cord injuries

Term
The central blood volume can be altered by 2 events, what are these?
Definition

-changes in total blood volume

-changes in distribution of total blood volume between central and extrathoracic regions

 

Term
Is cardia output increased/decreased by an increase in venous filling pressure?
Definition
increased
Term
Is venous filling pressure increased/decreased by an increase in cardiac output?
Definition
decreased
Term
Neural and hormonal mechanisms can control what 2 things?
Definition
central volume and arterial pressure
Term
Neural control of the CV system controls?
Definition
sympathetic and parasympathetic 
Term
The blood volume and arterial pressure are monitored by?
Definition
stretch receptors
Term
Sympathetic nerve activity and hormones serve as effectors for regulation of?
Definition
blood volume by regulation salt and water balance
Term
Neural control of cardiac output and systemic vascular resistance plays larger/smaller role in moment-by-moment regulation of arterial pressure?
Definition
larger
Term
What hormones are involved in regulation?
Definition

Arginine vasopressin

andiotensin II

aldosterone

atrial natriuretic peptide

 

Term
In autonomic control the heart is innervated by?
Definition
parasympathetic and sympathetic nerve fibers
Term
T/F:parasympathetic fibers tonically active
Definition
true
Term
Parasympathetic innervation- Acetylcholine released and binds to?
Definition
SA node, AV node, specialized conducting tissues
Term
In parasympathetic autonomic control there is ______intervation of ventricular muscle?
Definition
little
Term
Stimulation of parasympathetic fibers causes?
Definition
slowing of heart rate and decreased conduction velocity
Term
Are sympathetic fiber tonically active?
Definition
yes
Term
Sympathetic control autonomic control: Release _____, binds to B1 adrenergic receptors.  Where are the receptors located?
Definition

norepinephrine

-SA node, AV node, Specialized conducting tissue, all cardiac muscles including the ventricles

Term
Autonomic control of heart: stimulation causes ____heart rate, conduction velocity, and contractility.
Definition
increased
Term
Autonomic control:Control of heart rate is dominated by?
Definition
parasympathetic
Term
Autonomic control:Control of contractility dominated by?
Definition
sympathetic
Term
The 2 divisions of autonomic control work together or oppose each other?
Definition

oppose each other

increase in one=decrease in other

Term
Autonomic control:Arteries and veins receive_____ innervation only?
Definition
sympathetic
Term
Autonomic control: norepinephrine binds to which receptors in arteries and veins?
Definition
a1 adrenergic and B2 adrenergic
Term
Autonomic control: Activation in arteries and veins causes ____and increase in systemic vascular resistance
Definition
vasoconstriction
Term
Autonomic control: affinity of both B1 and B2 receptors of epinephrine is greater/less than for norepi?
Definition
greater
Term
Autonomic control: at high/low circulation concentrations epi activates only B receptors with effect of increasing cardiac output.  This action increases/decreases SVR?
Definition

low

decreasing

Term
Autonomic control: what is the net effect of sympathetic nerve activity?
Definition
maintenance of normal blood pressure
Term
When spinal cord acutely transected completely, excitatory signals can no longer reach sympathetic preganglionic fibers, tonic firing is reduced and blood pressure fails?
Definition
spinal shock
Term
What are the 3 major cardiovascular function of the medulla oblongata?
Definition

- generating tonic(maintenance) excitatory signals to spinal sympathetic pregangionic fibers

-intergrating cardiovascular reflexes

-integrating signals from supramedullary neural networks and from circulation hormones and drugs

Term
Where are reflex control in mechanoreceptors located?
Definition
aorta, carotid sinus, atria, ventricles, pulmonary vessels
Term
Are mechanoreceptors sensitive to stretch?  What happens when stretch occurs?
Definition

yes

when wall is stretched by increased transmural pressure (inside vessel), firing rate of nerves from mechanoreceptors increases

Term
Where are the baroreceptors located?
Definition
aorta, carotid sinus
Term
Where are the cardiopulmonary baroreceptors located?
Definition
atria, ventricles, pulmonary vessels
Term
Increased ____ pressure stretches baroreceptors?
Definition
BP
Term
Baroreceptors: increased action potential traffic reaching NTS leads to excitation and inhibition of ____ neurons?
Definition
Term
Baroreceptors: Results in increased ______neural activity to heart?
Definition

parasympathetic

-decreased sympathetic activity

Term
Baroreceptors: What is the net result?
Definition
decreased CO and SVR which results in deceased mean arterial pressure
Term
baroreceptor reflex influences ____ levels?
Definition
hormone
Term
What is the most important hormone influenced by baroreceptors?
Definition
renin-angiotensin-aldosterone system (RAAS)
Term
Baroreceptors: kidneys release renin which activates RAAS which?
Definition
increases vascular resistance causing kidneys to save salt and water increasing blood volume, and raises BP
Term
Baroreceptors: What causes decreased firing rate or baroreceptors?
Definition

-results in increased AVP

-AVP vasoconstrictor causing water retention by kidneys

-increase in blood volume

-increase in BP causes decreased AVP release and increased water excretion by kidneys

Term
Baroreceptors: when arterial pressure drops, vasoconstriction caused by baroreceptor reflex which does what?
Definition
spared the brain and heart, allowing flow to these two vital organs to be maintained
Term
Baroreceptors: Mean arterial pressure suddenly raised baroreceptor causing firing to decline/incline during the next few seconds.
Definition
declines
Term
Baroreceptors: The firing rate continues to decline/incline more slowly until it returns to the original firing rate over the next 1-2 days
Definition
decline
Term
Baroreceptors: are the first line of defense in sudden____changes
Definition

BP

-only works from moment to moment not long term

Term
cardiopulmonary: stretch receptors that sense?
Definition
central blood volume
Term

cardiopulmonary: unloading (decreased stretch) results in _____sympathetic nerve activity to heart and blood vessels and _____ parasympathetic nerve activity.

 

Definition

increased; decreased

-also activate RAAS and increased release of AVP

Term
cardiopulmonary: does unloading enhance/decrease baroreceptor reflex (aorta, carotid)
Definition
enhances
Term
cardiopulmonary: loading inhibits/enhances baroreceptor reflex
Definition
inhibits
Term
chemoreceptors: specialized structures in areas of carotid and aortic baroreceptors sense change in?
Definition
blood O2, CO2, and pH
Term
chemoreceptors: primarily involved with control of ?
Definition

ventilation

-also affect cardiovascular system through neurogenic reflexes

Term
chemoreceptors: Increased firing rate when?
Definition

-PO2 or pH or arterial blood is low

-PCO2 of arterial blood increased

-flow through bodies is low or stopped

-chemical given that blocks oxidative metabolism in chemoreceptor cells

Term

chemoreceptors: increased firing leads to?

-profound peripheral vasoconstriction/dilation

-elevation/decrease arterial pressure

 

Definition

vasoconstriction

elevation

-if respiratory movement voluntarily stopped, vasoconstriction more intense and a striking bradycardia and decreased cardiac output occur

Term
chemoreceptors: hypotension <80mmHg caused by?
Definition

-decreased blood flow through bodies

-chemoreceptor firing increases

-serves as secondary emergency reflex if BP continues to fall despite baroreceptor reflex action

Term
In cardiovascular response to pain there is?
Definition

increased sympathetic activity to heart and blood vessels

decreased parasympathetic activity to heart

Term

Cardiovascular response to pain leads to?

Is known as?

Definition

increased cardiac output, SVR, and mean arterial pressure

-cold pressor response

Term
Deep pain results in?
Definition

diminished sympathetic activity

-enhanced parasympathetic activity with

-decreased cardiac output, SVR, and BP

-contributes to cardiovascular shock from severe trauma

Term
Occurs in posterior and inferior myocardium which causes reflex bradycardia and hypotension, increased parasympathetic tone, dilation of systemic arterioles and veins?
Definition
myocardial ischemia
Term
What response causes autonomic rxn in response to fear or feeling threatened, elevated heart rate, BP, and increased sympathetic neural activity to blood vessels and the heart, increased skeletal muscle tone, and general alertness?
Definition
fight or flight response
Term
Stimulation of the cerebral cortex can lead to a sudden relaxation of skeletal muscle, depression of respiration, and loss of conciousness known as?
Definition
vasovagal sncope
Term
Profound parasympathetic-induced bradycardia, withdrawal of resting sympathetic vasconstrictor tone and a net dramatic drop in heart rate, cardia output, and SVR-vasodilation is caused by?
Definition
vasovagal syncope
Term
Intense slowing of the heart rate (parasympathetic) and peripheral vasconstriction (sympathetic) of extremities describes what kind of response?
Definition
diving response
Term
With breath holding arterial PO2 and pH falls and PCO2 rises causing
Definition
chemoreceptor reflex to reinforce diving response
Term
Why so conditioned responses of the heart hold clinical significance?
Definition

psychological stress can raise blood pressure, increase atherogenesis, and predispose person to fatal cardiac arrhythmias

-results from activation of fight or flight

Term
What hormones play a role in the control of the cardiovascular system and where do they come from?
Definition

EPI- adrenal medulla

AVP- posterior pituitary

Renin- kidneys

atrial natriuretic peptide- cardiac atrium

Term
What receptor does EPI bind to and what response does it cause?
Definition
B2-adrenergic receptors of skeletal muscle causing vasodilation
Term
EPI and NE have similar direct effects on the heart but NE elicits a powerful? WHy?
Definition

baroreceptor reflex bc it causes vasocontriction and increases mean arterial pressure

-also actos on a1 receptros in skeletal muscles and get vasoconstriction

-NE increases cardiac parasympathetic tone

Term

Low concentration of EPI causes

-vasco_____ in skeletal muscle bc activates B2 over A1 receptors of the arterial system

-SVR may fall/rise and mean arterial BP does not rise

-baroreceptor reflex in activted/not activated

Definition

dilation

fall

not activated

Term
High concentration of EPI results in?
Definition

binding to A1 receptors and causes peripheral vasocontriction

-only reached when administered as a drug

Term
Activation of the B2 and A1 receptors by EPI cause what respectively?
Definition

B2 vasodilation

A1 vascocontriction

Term
Reduced arterial pressure and blood volume cause the release of _____ from the kidneys?
Definition
renin
Term
Andiotensis II counteracts drop in arterial pressure by?
Definition

-arteriolar vasconstriction

-reduced Na secretion by increased Na reabsorption by proximal tubule of kidneys

-release of aldosteron from adrenal cortex which promotes Na reabsorption in distal convoluted tubules

-causes release of AVP from post pituitary gland promoting water reabsorption 

-enhances NE release, reducing NE uptake potentiating sympathetic nervous system effect

Term
What is the net result of Andiotensin II?
Definition
raise inBP
Term
Increase plasma osmolality, decreased baroreceptor and cardiopulmonary receptor firing, and various types of stress are the 3 primary classes of stimuli leading to?
Definition
AVP release
Term
AVP exerts its major effect on CV system by causing?
Definition
retention of water by kidneys
Term
Atrial natriuretic peptide is released when?
Definition

atria are stretched

-increase blood volume increases stretch

-leads to higher Na excretion and reduction in blood volume

Term
What are short term BP controls?
Definition

activation of neural reflexes

hormonal control mechanisms

Term
What are long term BP controls?
Definition

kidneys- responsible for setting mean arterial pressure values

depends upon salt and water excretion by kidneys

 

Term
Increased arterial pressure results in increased salt and water excretion called?
Definition
pressure diuresis
Term
As long as mean arterial pressure is elevated, salt and water excretion will exceed the normal rate bc of?
Definition
pressure diuresis
Term
Pressure diuresis persists until?
Definition

it lowers blood volume and cardia output sufficiently to return mean arterial pressure to original set levels

-decrease in arterial pressure has the opposite effect

Term
Insufficient organ blood flow accompanied by hypotension, direct cardia dysfuntion, and diminished venous filling pressure in preload are characteristics of?
Definition
circulatory shock
Term
What are the three stages of circulatory shock?
Definition

compensated shock

progressive shock

irreversible shock

Term
Normal CV regulatory mechanisms will compensate for the initial decrease in cardiac output and/or arterial pressure.  Activation of baroreceptor reflex stimulation of renin-andiotensin system, and release of AVP characterize?
Definition

compensated shock

-ex donation of blood

Term
Vicious positive-feedback cycle in which body in unable to compensate fully, heart and brain deteriorate as result of poor blood supply, and body cannot recover without CV support intervention characterizes?
Definition

progressive shock

-ex car accident and bleeding out in shock, must give meds to increase BP 

Term
In progressive shock coronary circulation is ______, myocardial contractility progressively increase/decreases, drop/raise in arterial pressure reducing coronary blood supply, basic/acidotic conditions promote arterial clotting, and deterioration of vasomotor centers in brain
Definition

compromise

decreases

drop

acidotic

Term
Without proper intervention, progressive shock will enter?
Definition
irreversible phase
Term
Decreased body temp, decreased mental function/unconsciousness, renal failure, and generalized muscle weakness characterize?
Definition
irreversible shock
Term
What is a type of circulatory collapse brought about by loss of neurogenic tone to veins and arteries?
Definition

neurogenic shock

-secondary to inhibition or dysfunction of CNS

Term
General or spinal anesthesia, traumatic brain injury, and depressed vasomotor center function from fever, stress, insomnia, or severe emotional distress are causes of?
Definition
neurogenic shock
Term
What is a severe allergic antigen:antibody rxn resulting in tremendous amounts of histamine being released into tissues spaces?
Definition
anaphylaxis
Term
What is disseminated infection throughout the body that next to cardiogenic shock is the leading cause of death from shock?
Definition

septic shock

-blood poisoning

Term
High body temp, and high cardiac output as a result of intense vasodiation in infected area are characteristics of?
Definition
septic shock
Term
In septic shock bacterial products stimulate production of _____ producing intense vasodilation?
Definition
NO
Term
Peritonitis secondary female reproductive organ infection, rupture of appendix, introduction of skin bacteria in bloodstream are causes of?
Definition
septic shock
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