fluid and electrolytes Flashcards
How much of body mass is water?
60%
How many mls are required per day for life?
1500 ml/day
How much water do we typically consume a day?
~2000 ml/day
what is a healthy daily water consumption?
4,000 ml/day
What does out water balance affect?
cardiovascular function (blood pressure)
temperature regulation
renal performance
What are some factors that affect water balance?
Burns sweating Dry air diarrhea drugs disease
What makes up total body water (TBW)?
intracellular fluid
extracellular fluid
what is extracellular fluid composed of?
interstitial fluid
intravascular fluid
lymoh, synovial, intestinal, biliary, hepatic, pancreatic, CSF, sweat, urine, pleural, peritoneal, pericardial, and intraocular fluids
Where does ADH (vasopressin) come from?
posterior pituitary
where does ADH act?
collecting Duct of Nephron
what does ADH do?
causes insertion of aquaporins into collecting duct which leads to water reabsorption by kidneys.
ADH
Antidiuretic hormone
What does ADH do?
regulates urine flow by increasing the permeability of the renal collecting duct to water.
more water is removed from the urine when ADH is present.
How do baroreceptors in the aortic arch and carotid sinus regulate ADH?
It sensing the decrease in blood pressure
How does the hypothalamic osmoreceptor regulate ADH?
it detects increased plasma osmolarity which then reduces blood volume.
right arterial stretch as well as a alcohol and caffeine _____ ADH release
inhibit
as blood pressure ______, urine flow _____.
as blood pressure increase, urine flow increases.
where is aldosterone released from?
adrenal cortex
what does aldosterone regulate?
sodium and potassium balance.
how does aldosterone increase sodium?
Sodium reabsorption from the urine and sweat
uptake from the gut
how does aldosterone decrease potassium?
by increasing secretion into the urine
ANP
Atrial natriuretic peptide or factor
the signal to increase or decrease blood volume
When is ANP released from the right atrium?
when the atrium is stretched as a cause of high venous blood volume and congestive heart failure.
what are pressures that determine the movement of water between vessels and tissues (capillary shift)?
hydrostatic pressure
oncotic pressure
hydostatic pressure
the physical pressure that the fluid is excerting on walls
a function os heart beat, water volume, gravity and vessel size
oncotic pressure
its kinda of a pulling pressure. Is there is a compartment with more “stuff” it will have a higher oncotic pressure. The more proteins the more it will pull water in.
it’s a function of plasma proteins
Capillary hydrostatic pressure
out of the capillary
plasma oncotic pressure
into the capillary
interstitial hydrostatic pressure
out of the interstitial fluid (into the capillary)
interstitial oncotic pressure
into the interstitial fluid (from the capillary)
How much water comes out the Arterial end of capillaries?
30mm Hg
How much water comes out of the venous end of the capillary?
10 mmHg
the hydrostatic pressure is _____ as the blood goes through blood vessels
reduced
Where is the high pressure zone in a capillary?
the arterial end
where is the low pressure zone in a capillary?
the venous end
Why is interstitial fluid hydrostatic pressure (IFP) negative compared to atmospheric pressure?
It is because of draining of fluid from the tissue by the lymphatic vessels.
the IFP is pushing toward the capillary but it’s not strong enough to counter the hydrostatic pressure pushing out so the net pressure is going out.
What is the value for interstitial hydrostatic pressure?
-3mmHg
neg bc its coming out then going in like it wants
Plasma oncotic pressure (POP)
The blood contains large amounts of protein and this exerts an osmotic pressure.
What is the value of the POP?
28 mHg going into the blood (capillary)
Interstitial fluid oncotic pressure (IFOP)
the interstitial fluid has small amounts of protein that pulls fluid into the tissues (out of the blood).
What is the value for IFOP?
8 mmHg out of the blood (capillary)
which pressures occur through the length of the vessel?
plasma oncotic pressure
interstitial fluid oncotic pressure
interstitial hydrostatic pressure