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hemodynamics Flashcards

1
Q

What is intravascular pressure secondary to? 5 Things

A
  1. Pressure arising from cardiac contraction producing cardiac output and peripheral resistance
  2. THe hydrostatic (water) pressure of blood = the pressure exerted by the blood itself in the closed circulatory system. Related to the specfic gravity of the blood
  3. gravitational forces on the blood. This is important with the patient in the upright position. Orthostatic hypotension. Blood pooling in the lower extremities
  4. The static filling pressure of blood: The pressure that exists becasue of the amount of blood in the vessel and eleasticity of the blood vessel wall
  5. friction
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2
Q

What are the 3 interchangeable forms of energy in the blood stream?

A
  1. Pressure secondary to cardiac output, elasticity of the vessels walls, peripheral vascualr resistance - this pressure is perpendicular presusre on the vessel walls called the transmural pressure
  2. hydrostatic pressure from gravitatiional forces. This can be minimized by having the patient supine.
  3. Kinetic energy of blood flow - remmeber this is largely related to teh velocity of the blood, ie greatest in the ascending aorta. This can be minimized by having the patient at rest.
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3
Q

Determinants of blood pressure.

A
  1. Blood volume
  2. effectiveness of the heart as a pump
  3. resistance of the system to blood flow
  4. Relative distribution of blood between arterial and venous blood vessels.
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4
Q

What is MAP?

A
  • MAP is the mean arterial pressure. It is the average blood pressure during a cardiac cycle. It can be measured invasively or can be estimnated by the following formula
  • MAP = (CO x SVR) + CVP
    • CO = cardiac output
    • SVR = systemic vascular resistance
    • CVP = central venous pressure
  • AKA MAP is proportional to CO times SVR
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5
Q

What is MAP considered to be seen by organs? What is needed to sustain the organs of an average person? Clinical significance?

A
  1. MAP is considered to eb the perfursion pressure seen yb organs int he body
  2. MAP of >60 is enough to sustain the organs of the average person
  3. MAP less than 60 does not adequately perfuse organs and they will become ischemic
  4. Clinical significance
    1. MAP is a better indicator of tissue perfusion than SBP
    2. Hence MAP is calculated for the management of patients with acute conditions when there is a concern for appropriate organ perfusion.
  5. AGAIN MAP IS PROPORTIONAL TO CO TIMES SVR (ALSO KNOWN AS TOTAL PERIPHERAL RESISTANCE
    1. MAP = CO X SVR
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6
Q

wHAT IS BLOOD FOW DRIVEN BY?

A
  • Blood flow through a vascular network is driven by pressure gradient (also called the perfusion pressure) from an aera of higher pressure ot an area of lower pressure
  • Flow is dependent on arterial pressure minus venous pressure divided by the resistance to flow.
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7
Q

How do you measure blood flow?

A
  • Blood flow is described by measuring the total volume of blood pumped by the ventricle per minute. ie the cardiac output
  • Blood flow is also the volume of blood moving past a reference point in a specifc point of time.
    • Measured in mililiters/minute.
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8
Q

What is the relationship between area and flow?

A
  1. Blood flow at any given point in a closed hydraulic system wil be equal to the flow at any other point
  2. Even through areas and velocities are changing, the flows at any given point are the same below.
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9
Q

Blood flow at any given point in a closed hydrualic system will be ____ to the flow at any other point?

A
  • Equal to the flow at any other point
  • Even though the areas and velocities are changing, the flows at any given point are the same.
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10
Q

What is the continuity equation?

A
  • States that the blood flow past any given point is proportional to the velocity of flow times the cross sectional areas.
    • Q(flow)= Area1 x Velocity1 = area2 x velocity2
  • The average velocity of blood at any given point within the circulation can be calcualted by knowing the volume of blood flowing (Q) past a given cross sectional area.
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11
Q

Fluid energy of blood is equal to? What is blood flow a function of?

A

The sum of kinetic energy and potential energy.

Blood flow is a function of the total fluid energy in the vascular system

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12
Q

Energy in the blood stream is in what 3 interchangeable forms?

A
  1. Pressure, secondary to cardiac output, elasticity of the vessel walls, and peripheral vascular resistance- lateral pressure on walls (called the transmural pressure)
  2. Hydrostatic pressure from gravitational forces
  3. kinetic energy of blood flow - rememebr this is largely related to the velocity of blood - ie greatest in the ascending aorta.
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13
Q

When are gravitational forces important in blood flow?

A
  • only imporatnt in the standing person. (orthostatic hypotension, coldstream guards, passingout when standing) they are not important in a horizontal patient.
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14
Q

What are the differenet blood values in a human?\

Body weight %?

Women and men amount?

A
  1. Blood comprises 7% of body weight
  2. a unit of blood is roughly one pint 473ml
  3. amount of blood people have depends on age, gender, weight, and height
  4. generally men have 4.5 to 6 quarts and women have 3.5 to 4.0 quarts
  5. A quart is .95 liters, therefore men have about 4.3-5.7 L and women ahve about 3.3-3.8L
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15
Q

What is cardiac output equal to?

A
  1. CO= SV x HR
    1. thus it is the volume of blood pumped by the ventricle in one minute (liters/minute)
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16
Q

How can cardiac output be regulated?

A
  1. parasympathetic nerves - affect cardiac rate by slowing, sympathetic increase rate
  2. stroke volume - MAP can affect stroke volume. (high map = low SV and vice versa). Frank starling law can also affect SV. Based on contraction strength and amount of EDV/volume in the ventricle.
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17
Q

What is the cardiac index?

A
  • To correct for the difference in patient size and shape, the cardiac index measures the cardiac output divided by the body surface area.
    • Cardiac index= CO/Body surface area.
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18
Q

Relative pressures in.

Systemic MAP

Mean pressure in capillaries

mean venous pressure in vena cavae

right atrium

right ventricle

venous pressure

left atrium and ventricle

A
  1. systemic arterial pressure int he brachial arteries is 120/80. Mean pressure is 100mmHG
  2. mean pressure in the capillaries is 50mmHg
  3. Mean venous pressure in the vena cavae is 4 mmHg
  4. pressure in the right atrium is 0-4
  5. right ventricle - 25/4
  6. pulmonary aretery - 22/8
  7. venous pressure - 8
  8. left attrium 8-10
  9. left ventricle - 120/10
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19
Q

what is pulse pressure?

A

Pulse pressure is the difference between teh systolic and diastolic pressure.

120-80=40mmgHg. This is the pressure that delivers the blood to the body.

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20
Q

What is the pressure waveform? Average MAP estimation?

A
  • Pressure waveform has a non-sigmoidal line. It is a pressure waveform for the blood in the aorta and it is not a flat line.
  • Estimation of MAP?
    • MAP is the average arterial press arterial pressure during a single cardiac cycle.
    • It can be estimated with
      • MAP = 1/3 systolic presure + 2/3 diastolic pressure
      • MAP = CO x SVR
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21
Q

Where does arterial vascular resistance primarily take place? What is the most important quantitative change for regulating blood flow?

A
  • There is resistacne to blood flow in the cardiocvascular system
  • Resistance takes place primarily in the arterioles
    • Changes in vessel diameter are the most important quantitatively for regulating blood flow through an organ.
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22
Q

Describe the blood flow in arteries?

A
  1. Blood flow in arteries is
    1. pulsatile - secondary to cardiac contractions
    2. laminar - blood flows in layers (lamina) within the aterial lumen (channel, opening of the hollow tube) friction between layers results in a parabolic flow profile
    3. Blunted by turbulence secondary to narrowing and tortuosity of vessels
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23
Q

describe laminar flow

A
  • blood flows in layers (lamina) within the aterial lumen (channel, openin of hollow tube). Friction between the layers results in parabolic flow profile.
    • In non-turbulent, laminar steady flow of a viscous fluid through the tube is a parabola. the peak velocity occuring the the centre of the tube, and zero velocity occuring for a layer of fluid lining the walls of the tube (the no-slip boundary condition)
    • The central - midsteram velocity is twice the average fluid flow velocity across the tube
  • The flow resistnace in laminar flow is due to viscous resistance, ie the viscosity of the blood.
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24
Q

Describe turbulent flow, when does it occur?

A
  1. Tubulent flow occurs with narrowing (stenosis) and toruosity of the blood vessel, primarily arteries.
    1. Turbulent flow is disorganized, multidirectoinal, irregular, swirly, flow with eddy currents and there is increased flow resistance from the turbulence.
    2. Turbluent flow causes a loss of energy and thus a drop in blood pressure distal to a stenosis
    3. therefore, in order to maintain perfusion of an organ, say the heart, greater presssure is required.
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25
Q

What is the sounds of turbulence?

A
  1. The sounds of some heart murmurs and the Korotkoff sounds heard when measuring blood pressure are from turbulence.
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26
Q

What is hematocrit? What does it do to blood?

A
  1. The viscosity of the blood is the measure of thickness of blood
    1. This depends on hematocrit, this is the amount of RBC in the blood. The higher the hematocrit, the higher the viscosity
  2. Viscosity is also dependent on temperature and flow rate.
  3. Low flow rates and stasis increase cell adhesion and thrombus formation
  4. The greatest work the heart performs is overcoming viscous resistance.
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27
Q

What is elasticity in terms of arterial walls?

A
  1. Elasticity of arterial walls is determined by the elastic fibers in the tunica media of the walls.
  2. The stretched walls return to the original state
  3. The force causing deformation is called stress.
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28
Q

What are doppler flow wave forms in normal vs stenosed vessels?

A
  1. Doppler flow wave forms.
    1. Normally with a parabolic laminar flow the specturm is narrow and spectrum of velocities is narrow
    2. In a stenosed vessel, the veloscity is increased and there is a broad spectrum of velocities giving a broad spectral display
    3. Beyond the stenosis, there is turbulence secondayr to the increase in the vessel diameter, overall slowing of velocity, but the broad specturm of velocities.
      2.
29
Q

What are the hemodynamics of stenosis?

A
  1. Doppler sonography shows the direct and indirect effects of occlusive disease.
  2. There needs to be approximately 80% stenosis (the critical area) before a measureable decrease in flow is seen.
  3. Note the vessel diamter decreases, the mean velocity begins to increase rapidly, then the flow rate falls off. Then at a critical narrowing, the velocity and flow rate go to zero, total occlusoin.
  4. As a general rule, as diamter of vessel becomes more narrow - velocity increases but flow rate decreases. Then at a certain point velocity tanks, and with flow rate they both go to zero.
30
Q

What is aterial blood pressure dependent on?

A
  • Stroke volume, compliance, and elastic rebound of the aorta (dicrotic notch), and resistance to blood flow (primarily in the arterioles)
31
Q

Describe the dicrotic notch and wave

A
  1. immediately after the aortic valve closes, there is a dip in the aortic wave form. This is the dicrotic notch.
  2. The aorta has an elastic rebound and there is a breif reversal of blood flow in the aorta which creates the dicrotic wave.
32
Q

What is blood presure proportional to?

A
  • Blood pressure is proportional to the COxTPR
  • Blood pressure is proportional to the SVxHR x TPR
33
Q

What is cardiogenic shock and what is septic shock?

A
  1. Cardiogenic shock: Cardiac disease causes a low cardiac output. This is compensated for by an increase in systemic vascular resistance
    1. low CO, high SVR
  2. Septic shock: bacterial toxins cause extensive peripheral vasodilated with decreases SVR. This is compensated by an increase in cardiac output
    1. high CO, low SVR
34
Q

What are intrinsic and extrinsic mechanisms of control of BP and blood flow

A
  1. Intrinsic
    1. blood flow in most tissues is proportional to metabolic needs
      1. autoregulation of blood flow
  2. extrinsic
    1. nervous system
    2. hormonal control.
35
Q

Describe autoregulation - intrinsic regulation of blood flow.

A
  1. Vasodilation - leads to increased flow when tissue senses
    1. chemical changes, decreased oxygen, decreased pH or increased CO2 and lactic acid or nitrous oxide
    2. blood flow can increase 7-8 times as a result of vasodilation of arterioles and precapillary muscle sphincters
  2. Vasoconstriction: occurs when tissue senses
    1. chemical changes, incrased oxygen, increased sympathetic stimulation, vasopressin, angiotensin II, and cold.
36
Q

Describe the extrinsic factors in regulation of blood flow.

A
  1. Extrinsic regulation of blood flow
    1. sympathoadrenal stimulation increases cardiac output and increases total peripheral resistance
    2. Baroreceptor and chemoreceptor responses
    3. renin angitotensin aldosterone system
    4. atrial natriuretic peptide mechanism.
37
Q

What are 7 factors that can control blood pressure?

A
  1. High pressure baroreceptors (pressure receptors, pressoreceptors)
  2. low pressure baroreceptors
  3. renin-angiotensin - aldosterone system
  4. epinephrine and norepinephrine
  5. atrial natriuretic mechanism
  6. vasopressin (antidiuretic hormone) system
  7. diuretics
38
Q

High pressure baroreceptors location and function

A
  1. High pressure baroreceptors are in the carotid sinus and aortic arch
    1. they sense pressure
  2. These are mechanoreceptors senstive to blood pressure, the baroreflex
  3. this reflex is mediated via the glossopharyngeal nerve to the medualla to the vagus nerve.
  4. Increases pressure stimulatesthe vagus nerve to decrease the heart rate and decrease contractility of the heart
  5. carotid massage stimulates the carotid baroreceptors. what is the downside of carotid massage?
    1. Cause an increase of pressure on the receptors - decreases BP
    2. dis - dislodging clots.
39
Q

Low pressure baroreceptors control and location

A
  1. Low pressure baroreceptors sense blood volume in low pressure receptor zones: atria, vena cavae, and pulmonary veins
  2. When increase blood volume sensed
    1. decreased secretion of antidiuretic hormone to decrease salt and water retention by the kidneys
    2. increased secretion of atrial natriuretic peptide to increase vasodilation and increased sodium and water excretion.
    3. renal vasodilation increasing salt and water loss
    4. increased heart rate
  3. and vice versa. If low blood volume is sensed - activates the RAAS
40
Q

Renin-angiotensin-aldosterone system

A
  1. When there is low blood flow or low pressure in the renal arteries, renin is secreted.
  2. Renin converts angiotensinogen to angiotensin I
  3. Anigotensin converting enzyme (ACE) converts angiotensin I into angiotensin II which is a potent vasoconstrictor
  4. Angiotensin II also stimulates aldosterone secretion in the renal cortex. Aldosterone acts on the kidneys to reabsorb sodium and water, thus increasing the blood volume.
41
Q

Control of ABP of epinephrine and norepinephrine

A
  1. From the adrenal medulla and neurotransmitters int he stympathetic nervous sytem
  2. acts to increase the heart rate and increase cardiac contractility
  3. acts to relax smooth muscle in airways
  4. acts to contact smooth muscle in arterioles incresaing peripheral resistance and increasing blood pressure.
42
Q

ANP mechanism. What is linked in this process?

A
  1. Stretch in the atria due to increase BP releases ANP
  2. ANP goes to three targets
    1. JG apparatus of the kidney
      1. decreases renin release - RAAS system inhibited
      2. causes vasodilation
    2. hypothalamus and posterior pituitary
      1. decrease ADH release and inhibits collecting ducts on kidneys from resorbing Na and H20
      2. decreases blood volume
    3. Adrenal cortex
      1. decreases aldosterone release
      2. less na+ and h20 is absorbed - inhibits collecting ducts of kidneys
      3. more na and h20 is excreted
      4. decrease in blood volume
    4. all decrease blood pressure.
43
Q

What does vasopressin do?

A
  • Vaospressin and RAAS work via the kidneys
    • Vasopressin is also called ADH
      • Vasopressin works to reabsorb H20
      • H20 reabsorption helps to prevent further osmolarity increase
44
Q

Control of arterial blood pressure based on the BP equation is?

A
  1. BP = CO x TPR
  2. BP = (SVxHR) x TPR
  3. Blood volume is decreased by diuretics such as hydrochlorothiazide and spironolactone
    1. act on kidney to decrease blood volume
  4. The RAAS is treated by an ACE (angiotensin converting enzyme) inhibitor.
    1. Blocking conversion of ACE1 to ACE2
  5. The RAAS system is also treated by blocking aldosterone inhibitors
    1. spironolactone
      1. inhibits aldosterone from reabsorbing sodium and water
  6. beta blockers (sympatholytics) block epinephrine receptors,
    1. propanolol
45
Q

What are the determinants of resitance to blood flow?

A
  • whether the vessels creating resistance are in series or parallel
  • What is the overall area/diamter of th eparts of the circulatory system
  • How is the resistnace being changed by the body
    *
46
Q

What is the distribution of vascular resistance?

A
  1. 50-60% of resistance is in the small arteries and arterioels
  2. 25% of resistance is in the capillareis
  3. 20% of resistance is in the large arteries
  4. 5% of resistance is in the veins.
47
Q

Resistance to blood flow arteries/arterioles vs capillaries

A

the small arteries and especially arterioles ahve smooth muscle which makes their vascular beds the most responsive to active reistance to blood flow

Capillareis do not have muscle alls and hae a passive resistance to blood flow.

48
Q

Blood vessels in series or parallel resistance change

A

Resistance increases when blood vessels are connected in series and decreases when they are connected in parallel

  • The resistance of a system in series is always greater than the resistance in any one vessel
    • The human circulation is two pumps in series.
  • the resistance of a system in parallel is always less than the resistance of any one vessel.
49
Q

Resistance in blood flow and cross sectional area

A

the cross sectional area of arterioles and capillary beds is greatest so that flow is diminished through them.

We know blood pressure is proportional to the total peripheral resistance, therefore, the largest drop in blood pressure will occur in the arterioles where there is the mos dramatic increase in overall cross sectional diamter.

50
Q

vasodilators do what to aterioles and capillaries

A

they dilate arterioles in a tissue bed and will decrease pressure proximal tothe arterioles but increase pressure in the capillary bed

Vasoconstrictors that constrict the arterioles will increase the blood pressure proximal to the arterioles but dedcrease the pressure in the capillary bed

51
Q

The following also contribute to the resistance of blood flow

A
  1. blood vessel radius - most significant component of resistance
  2. blood viscosity - thicker the blood the more energy is required to pump
  3. vessel length - friction along edges
  4. friction - force resisting the motion of an object, see laminar flow
  5. turbulence - secondary to irregular and narrow blood vessels.
52
Q

Pressure gradient equation

A
  1. The pressure gradient across a segement of blood vessel is proportional to the flow across the segment and the resistance across the segment
  2. pressure gradient = flow x resistance = q x r
  3. therefore flow = pressure gradient/resistance
  4. thus to increase flow you need to increase the pressure gradient and or decrease resistance.
53
Q

Given the contributions to the resistance to blood flow, outlined above, resitsacne is proportional to the radius of the vessel, the length of the vessel and the viscosity of the blood

resistance = 8LV/PiR^4

thus, pressure gradient is?

A

Pressure gradient = 8 Q L V / pi r^4

This equation is poiseuille’s law

Q is the fow through the segment, L is the length of the segment, V is the viscosity of blood, generally the viscosity of blood is 3 to 4 times greater than the viscosity of water, and is a function of hematocrit

r is the radius of the vessel. the 4th power makes the radius the greatest effect on resistance.

54
Q

Poiseuille’s law in words.

A
  • As length and viscosity increase the resistance increases
  • Smaller vessels have increased resistance, in fact the arteriorlar bed is where most reistnace actively occurs as the arteriole has constricting smooth muscle that makes the radius smaller.
  • you also need to consider the total area of the components of the vascular bed
  • atherosclerosis also narrows the vessel radius increasing resistance. When the diameter of the vessel is 50% or more, it becomes hemodynamically significant
  • Collateral vessels ahve greater length and thus greater resistance.
55
Q

Viscosity as a function of hematocrit

A
  1. As hematocrit increases, viscosity increaess, but not lineraly
  2. polycythemia means increased viscosity
  3. anemia means decreased viscosity
56
Q

What are the two low resistance systems?

A

Brain and kidneys

for their size they recieve a disproportionately large amount of blood flow

15-20% of cardiac output.

57
Q

What are the two ways to regulate blood flow?

A
  1. regulation of the rate of blood flow moving through the circulatory system
  2. regulation of the rate of blood flow moving into and out of a given area of the body.
58
Q

What are normal rates for SV, EF, HR, CO

A
  1. Stroke volume is the volume of blood ejected from the heart with each contraction of the left ventricle, normal is about 55-100ml per contraction. Around 70
  2. Ejection fraction is the fractin of blood ejected from the ventricle with each contraction. Normally about 55-70%
  3. Heart rate is the beats per minute, normally 60-80bpm
  4. Cardiac output is the volume of blood ejected from the left ventricle in one minute
    1. co=svxhr
59
Q

Integrity of what is key to producing adequate cardiac output.

A

The key to producing an adequate CO is the integrity of the myocardium

Can see this in starling law, ischemia/infarction, heart failure leading to decreased cardiac output.

60
Q

Control of heart rate is determined by what?

A
  1. Baroreceptors (pressoreceptors) in the carotid sinus and aortic arch
    1. a mechanoreceptor sensitive to blood pressure, the baroreflex via glossopharygneal n to medulla to vagus nerve
    2. increased pressure stimulates the vagus nerve to decrease heart rate and vice versa
    3. carotid massage stimulates carotid baroreceptors
  2. exteroreceptors in the skin will stimulate decreased HR in cold and increased in the heat
  3. exercise: note that with heavy exercise, the cardiac output markedly increases and proportionately the muscles get the most blood.
    1. Muscles go from 0.75L/min to 20L/min
61
Q

Control of peripheral resistance is determined by what?

A
  1. peripheral resistance is primarily controlled by the expansion (vasodilation) and contraction (vasoconstriction) of the arterioles
  2. At any given time, a large number of arterioles are contracted to maintain blood pressure. If all the arterioles were dilated at the same time the blood pressure would drop catastrophically. This occurs in septic shock.
  3. Neurologically, the sympathetic nervous sytem controls the arterial and the arteriolar vascular smooth muscle through adrenergic receptors responding to primarily norepinephrine.
    1. alpha 1 receptors cause vasoconstriction activated in shock and hypotension
    2. alpha 2 receptors cause vasoconstriction
    3. beta 2 receptors cause vasodilatoin and hypotension
  4. A reduction in oxygen (hypoxia) and an increase in carbon dioxide will cause vasodilation.
    1. local ischemia (decrease in oxygenated blood) will also cause vasodilation
    2. after a meal (post prandial) ther will be vasodilatoin and increaesd flow in the splannchic circulation. In celiac disease this may not occur.
62
Q

How are veins characterized?

A

Thin walls, distensible and collapsible (they are a high capactiance system)

Meaning they can take an increase in blood volume without changing pressure much

63
Q

What will cause increased venous return? What does this cause?

A
  • This is one of the primary mechanisms by which cardiac output is increased rapidly. Veins smooth muscles can contract.
    • lying down will increase venous return to the heart
    • valsavla maneuever will decrease venous return to the heart.
64
Q

Where is most of the blood in the circulatory system?

A

60-75% of the blood is in the venouys sytem. a large part in the lower extremities.

65
Q

What is phasicity?

A

This describes venous flow. Phasicity is the ebb and flow response to respriation. Inspiratoin and expiration and right atrial cardiac transmitted pulsations.

With standing inspiratoin the pressure within the thorax decreases and venous blood flows into the chest. The intraabdominal pressure increases and squeezes the intra abdominal veins increaing their pressure. This increase in the resitance to flow from veins in the lower extremities

With experiation it is vice versa.

66
Q

How does gravity affect the blood in the venous system? How does it get back to the heart standing up. What pressures are relative?

A
  • Because of the capacitance of veins, the blood in them is responsive to gravity.
    • Hydrostatic pressure is the primary factor in determining intravascular pressure within the venous system.
  • When supine, the pressure in the leg veins is almost equal to the right atrial pressure. With standing, the pressure in the ankle veins goes from 10mmHg supine to 90+mmHg standing. With the calf muscle pump (see below), this pressure can be reduced to about 30 mmHg.
    • With standing, about 250 ml blood pools in the lower extremities
    • To handle this increased hydrostatic pressure in the lower extremities, the body has developed venous valves to prevent reflux (back flow) and the pumping action of leg muscles (calf muscle pump) to propel blood towards the heart. The valves in the perforating veins direct blood to the deep veins.
67
Q

What happens when blood pools in the lower extremity veins?

A

When blood pools in the lower extremity veins, the increased hydrostatic pressure causes edema.

When enough blood pools in the lower extremity veins, you have a decreased amount of blood to the heart and resulting syncope (Coldstream Guards)

When you are sitting or standing and not using your lower extremity muscle, DVT (Deep Venous Thrombosis) can occur.

68
Q

what is virchow’s triad?

A

Virchow’s Triad: Factors thought to contribute to DVT, hypercoagulability, stasis, endothelial injury.

69
Q

Lymphatic system averages how many liters of plasma a day?

A

An average of 20 liters of plasma passes out of the capillaries per day , with about 17 liters reabsorbed. The remaining 3 liters is taken up by the lymphatic system and returned to the venous system.

random patho (6 decks)

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