Studied by 0 peopleWhat does the circulatory system transport?
oxygen and nutrients
The circulatory system removes _____.
metabolic wastes
The circulatory system is arranged in a _____.
circuit
Arteries and veins have _____ distinct layers.
three
Arteries are _____ than veins.
thicker
Veins have a _____ lumen and valves that arteries.
larger
_____ is a single thickness of endotherlial cells.
capillaries
Capillaries continue to narrow to a diameter only as big as an _____.
rbc
The capillary bed in brain has little space between endothelial cells resulting in the…
blood brain barrier
The capillary bed in kidneys has more space between endothelial cells which allows…
much larger molecules to move between (filter)
What is pulmonary circulation?
moves blood through the lungs and creates a link with the gas exchange function of the respiratory system
Pulmonary circulation is the _____ side of the heart.
right
What parts of the heart is pulmonary circulation?
pulmonary artery, capillaries, and veins
What is systemic circulation?
supplies all the other tissues of the body
Systemic circulation is the _____ side of the heart.
left
What parts of the heart is systemic circulation?
-Aorta and its branches
-Capillaries supplying the brain and peripheral tissues
-Systemic venous system and the vena cava
What is central circulation?
blood that is in the heart and pulmonary circulation
What is peripheral circulation?
blood that is outside the central circulation
What does lymphatic circulation contain?
channels and nodes
Lymphatic circulation starts deep in _____ tissue.
connective
What is lympathic circulation?
reabsorb fluid (lymph) that leaks out of vascular network and returns to general circulation
Lymph is derived from _____.
interstitial fluids (plasma proteins and other osmotically active particles)
Lymphatic system filters the fluid at the lymph nodes and removes…
foreing particles such as bacteria
What is hemodynamics?
principles of circulatory blood flow
What are the pressure principles of flow?
-blood moves to lower pressure (arteries to capillaries)
-greater the pressure difference the faster the blood flow
What are the velocity principles of flow?
longer the distance, the decrease in velocity
What are the laminar/turbulent flow principles of flow?
-laminar is less friction, turbulent is disordered flow
-turbulent flow decreases velocity too
What are the wall tension principles of flow?
affected by wall thickness (arteries less compliant, veins very compliant)
If wall pressure falls, vessels _____.
collapses
_____ decreases as blood flows from arteries to capillaries.
mean pressure
What is laminar blood flow?
-layering of blood components in the center of the bloodstream
-reduces frictional forces and prevents clotting factors from coming in contact with the vessel wall
What is turbulent flow?
-Disordered flow
-The blood moves crosswise and lengthwise in blood vessels.
-Describes the relation between wall tension, transmural pressure, and radius
-States that wall tension becomes greater as the radius increases
Wall tension _____ as the wall becomes thinner.
increases (decreases as the wall becomes thicker)
What is the resistance principle of blood flow?
force that opposes movement of blood
What are determinants of resistance?
vessel length and vessel radius
Shorter vessel length; _____ resistance.
less
Larger vessel radius; _____ less resistance.
larger
Some disease processes alter the _____ of the vessel. (atherosclerosis)
radius
Viscosity of blood _____ resistance.
increases (higher hct leads to higher resistance)
What is total peripheral resistance?
resistance throughout the entire vascular system
Total peripheral resistance is also known as _____.
systemic vascular resistance (SVR)
Conditions that _____ systemic vascular resistance cause more work on the heart.
increase
What is microcirculation?
smallest vessels of vascular and lymphatic system
What is the capillary bed’s role in microcirculation?
to exchange gas and nutrients
Materials exchanged through diffusion move along the _____.
concentration gradient
Materials exchanged through filtration move along the _____.
pressure gradient
What is capillary fluid pressure?
-blood pressure in the capillary \n -force pushing fluid from capillary into interstitum (hydrostatic \n pressure)
What does capillary fluid pressure depend on?
BP, flow, and resistance
What is plasma colloid osmotic pressure?
\n -plasma proteins responsible (albumin) \n -large molecules cannot move out of capillary space \n -number of dissolved molecules determines plasma colloid osmotic pressure
If pathology is an alteration in lymphatic flow then _____ develops.
lymphedema
What is edema?
excess interstitial fluid in the tissue
What are the causes of edema?
-imbalance of any of the factors that control movement of water between the vascular compartment and the tissue spaces \n -disproportionate increase in capillary fluid pressure or \n permeability, decreased capillary colloidal osmotic pressure, or impaired lymph flow
What is vasomotor tone?
contraction of vascular smooth muscle
_____ is alpha receptors.
vasoconstriction
_____ is beta adrenergic receptors.
vasodilation
What are veins?
skeletal muscle activity activates venous pump \n forcing blood back to heart
What is autoregulation?
ability of blood vessels in organs to maintain constant flow
Lymph flow is enhanced by:
increased activity, increased BP, and increased RR
What is arterial blood pressure?
the pressure differences between the left and right \n sides of the heart that produce the gradient allowing \n systemic movement of blood
What is arterial blood pressure produced by?
the force of left ventricular contraction overcoming the resistance of the aorta to open the aortic valve
Arterial diameter affects arterial resistance therefore _____.
blood pressure
_____ = CO x SVR
blood pressure
Alteration of cardiac output and SVR alters _____.
blood pressure
What is systolic?
peak pressure in aorta during ventricular contraction
What is diastolic?
pressure during ventricular diastole
What is the difference between systolic and diastolic called?
pulse pressure
What is mean arterial pressure (MAP)?
calculated average pressure within the circulatory system throughout the cardiac cycle
What is the formula for mean arterial pressure?
(2x diastolic) + systolic /3
What is the direct measurement of blood pressure?
arterial line; waveforms
What is the indirect measurement of blood pressure?
BP cuff measurements (cuff size affects and should be the same in both arms unless condition present)
What are some things that affect BP?
stress, HR, activity, and position
What is the systolic blood pressure?
peak pressure during cardiac systole
What is diastolic blood pressure?
lowest pressure during cardiac diastole
_____ is the primary factor influencing systolic pressure.
stroke volume
_____ is the major determinant of diastolic pressure.
systemic vascular resistance
What is the pulse pressure formula?
systolic - diastolic
What is the sympathetic nervous system?
baroreceptor reflex and vasomotor center in medulla
Vasomotor center is activated by:
fever or stressors
Parasympathetic nervous system _____ HR.
slow
What is the primary function of the heart?
-pump blood through circulatory system \n -distributes oxygenated blood and nutrients to tissues
What is oxygen rich blood?
enters the heart from the lungs and goes out to the body
What is oxygen poor blood?
enters the heart from the body and goes out to the lungs
What is cardiac output (CO)?
amount of blood pumped out of the heart each minute
What is the cardiac output formula?
CO = HR x SV
What is stroke volume (SV)?
amount of blood ejected from the ventricle with each \n contraction
What is preload?
volume of blood in heart
What is contractility?
contractile capability of the heart
What is afterload?
impedance/resistance opposing ejection of blood from ventricle
What is ejection fraction?
influenced by preload, contractility, and afterload
What is the SA node?
pacemaker of the heart (60-100)
What is the AV node?
back up if SA node fails (40-60)
What is the echocardiography?
reflected sound waves (US) provides image of structure and motion
What is the nuclear cardiography?
radioactive tracing of blood flow patterns
What is cardiac catheterization?
structural and hemodynamic characteristics (direct measurement of pressures, visualization)
What does reduction in blood flow impair?
ability to transport oxygen, nutrients (arterial) or to return flow to remove metabolic waste (venous)
What is a thrombus?
a clot
What is an embolus?
a clot that is on the move and we don’t know where it is going to lodge
What does a thrombus obstruct flow of?
arterial and venous flow
What does a embolus obstruct flow of?
arterial and venous flow
What does a vasospasm obstruct flow of?
arterial flow
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