the movement of WATER btwn two compartments separated by a semipermeable membrane.
Water moves thru the membrane from an area of of low solute concentration to an area of high solute concentration.
Water moves from the more dilute compartment (more water) to the side that is more concentrated (less water)
movement of molecules from high concentration to low.
Stops when concentrations are equal in both areas.
(liquids, gases, and solids)
molecules moving against the concentration gradient using ATP as it's energy.
Example of active transport
sodium moves out of the cell and potassium moving in to the cell to maintain a concentration gradient.
Oncotic pressure/Colloid osmotic pressure
osmotic pressure exerted by colloids (proteins) in a solution.
Proteins attracting water, pulling fluid from the tissue space to the vascular space.
Proteins are too large to get out of the vascular space.
ECF is made of
Consists of interstitial, intravascular and transcellular fluid
ICF is made of
Consists of fluid within the cell itself
used to describe fluids inside the body...
ie-concentration of urine and plasma
used to describ fluids outside of the body.
normal is btwn 275-295
above 295 =high concentration or low water content "water deficit"
below 275=little solute for the amount of water or too much water "water excess"
Solution in which the solutes are less concentrated than the cell...
Solution in which the solutes are more concentrated than the cells ....
If a cell is surrounded by hypotonic fluid, water moves....
in to the cell causing it to swell and possibly burst
If a cell is surrounded by hypertonic fluid, water moves....
out of the cell to dilute the ECF, causing the cell to shring and possible death
transfer of water and dissolved substances thru a permeable membrane from a region of high pressure to low pressure
Insensible losses are from respiration and fever. They are pure water losses and are __________ losses. Leaving the body fluids in a ___________state.
Positively charged ions
Cations-Ca, K and Na
Negatively charged ions
Anions-Cl (chloride) and HCO3 (bicarb)
General functions of electrolytes (4)
promote neuromuscular irritability needed for proper functioning of nerves and muscles
regulate acid/base balance
distribute body water btwn fluid compartments
maintain body fluid volume and osmolality
Water moves in same proportion as body fluids
D5W (w is water)
D5 1/4 NS
D5 & 1/4 NS
LR (Lactated Ringer)
Causes less movement of body water than body fluids do.
1/2 NS (0.45% sodium chloride solution)
1/4 NS (0.225% sodium chloride solution)
Causes more movement of water than body fluids do
3% (or greater) Sodium Chloride Sol.
10% (or greater) D/W
5% D 1/2 NS
5% D/0.9% NS
5% D in Ringers Lactate Solution
Increased Osmolarity and Osmolality and Hyperosmolar =
Increased particles in the solution
Hypertonic, Decreased Osmolality and Osmolarity, and hypo-osmolar and hypotonic=
Decreased particles in the solution
How much water do the lungs remove daily through exhalation?
300mL....insensible water loss
What does ADH do?
Causes the body to retain water by water reabsorption
If the body senses too high of BP...what does it do?
decreases the amount of ADH released, allowing for water loss
What does the secretion of Aldosterone do?
causes sodium and water to be retained and the excretion of potassium
decrease in aldosterone causes sodium and water loss and potassium retention
What does Angiotensin II do?
stimulates the adrenal cortex to release Aldosterone
causes vasoconstriction of arterial smooth muscles.....increasing BP
Parathyroid Hormone does what?
increased PTH causes elevated serum calcium and lowered serum phosphate.
decreased PTH causes lowered serum calcium and increased serum phosphate.
Elevation of one means a decrease in the other
When plasma proteins are lowered, by colloid osmotic pressure, the fluids are shifted from the intravascular compartments in to the interstitial space. These fluids are not available for use by the body. (ascites)
How much urine should we expel in 24hrs or per hour?
30mL's for 2 hours....call Dr.
minimal amount is 400-600mL/day
Fluid loss in stool, respiration and perspiration
an equal loss of fluids and electrolytes from the ECF
NO shift of fluid from intracellular space-lose sodium and water in = amounts
What causes isotonic dehydration?
losing more solutes from the ECF than water
Causing ECF to have a lower osmotic pressure than ICF so fluid shifts from ECF to ICF causing vascular swelling
What causes hypotonic dehydration?
Chronic renal failure
Over admin of hypotonic IV fluids (0.45 NS or D5)
a greater loss of EC Fluid than electrolytes
Causes a shift of fluid from ICF to ECF, resulting in cellular dehydration and shrinking
What are serum sodium levels in hypotonic dehydration and hypertonic dehydration?
hypotonic sodium is low
hypertonic sodium is high
What causes hypertonic dehydration?
decreased water intake
excess loss of water without loss of elctrolytes
increased solute intake without sufficient water
excess accumulation of solutes due to disease process
Example of decreased water intake that causes hypertonic dehydration
NPO for a procedure....procedure may get pushed back to NPO for all day!
Example of excess loss of water without loss of elctrolytes causing hypertonic dehydration
increased respiratory rate
Example of increased solute intake without sufficient water that causes hypertonic dehydration
Example of excess accumulation of solutes due to disease process causing hypertonic dehydration
S/S of deficient fluid volume
Subjective-c/o dry mouth, dysphagia, weakness, hx of vomiting, diarrhea, polyuria
Objective-output greater than intake
dry skin-tenting turgor
Increased HR, RR and depth, temp, but decreased BP
Decreased urine output
Elevated specific gravity-above 1.0125
When you have deficient fluid volume what happens to H&H?
it will increase but you dont have more blood cells
What happens first when a person has deficient fluid volume?
decreased urine output
Where do you assess skin turgor in the elderly?
S/S of fluid volume excess:
Subjective-SOB, weight gain, fatigue, HTN, Hx of cardiac or renal disease, steroid therapy, history of use of excessive tap water enemas
S/S of fluid volume excess:
pedal or sacral edema (+1-+4)
Shiny taut skin
Increased BP, bounding pulse
Decreased urinary output
Change in behavior-confused and lack of coordination
accumulation of fluid in all body tissues-can hear as fluid in lungs
What causes fluid volume deficienty?
What causes Isotonic fluid volume excess?
causes ECF excess and edema
Increased secretion of Aldosterone
What causes hypo-osmolar volume excess aka water intoxication?
causes Cellular edema....
excess intake of electrolyte free fluids-athelete drinking pure water
Interventions for fluid volume deficiency
Control vomiting/diarrhea/reduce fever
replace fluid loss as order by MD(IV or parentally)
BP test to see if a pt has fluid volume deficiency....
BP taken laying, sitting and standing with 2 min. btwn each.
+ sign is 15mmhg drop in systolic or 5 mmhg drop or +10 in diastolic
How do you treat isotonic dehydration?
replace with isotonic iV solution
How do you treat hypertonic dehydration?
replace with isotonic or hypotonic solutions (solutions that contain less electrolytes or solutes than the bloodstream)
How do you treat hypotonic dehydration?
replace with isotonic or hypertonic solutions (solutions that contain more electrolytes or solutes than the bloodstream
Interventions for fluid excess...
Encourage pt. to decrease salt intake
keep edematous extremity elevated above heart
Fluid restriction as ordered
Normal Serum Na levels
Normal serum Potassium levels
Normal serum calcium levels
S/S of hyponatremia
delussions and hallucinations
Biggest symptoms of hyponatremia are brain issues...why?
it causes brain cells to swell....cerebral edema and ICP
S/S of hypernatremia
Dry, sticky mucous membranes
low urinary output
rubbery tissue turgor
S/S of hypokalemia
apathy, confusion, coma
No clinical symptoms in mild cases
Initially-skeletal muscle spasms
Later-muscles become weak
S/S of hypocalcemia
muscle spasms and rigidity
Tingly lips, nose and fingertips
Anxiety, irritability, seizures
Where do you first notice muscle spasms for hypocalcemia?
hands and feet
Chvostek sign-cheek spasm
Trousseau's sign-blood pressure cuff tightened and muscle contraction occurs at hand and wrist
S/S of hypercalcemia
GI upset-anorexia, NV and constipation
Lethargy, confusion, coma
Bone and flank pain (kidney stones)
What causes hyponatremia?
What should you irrigate GI tubes and body cavities with? Why?
Using water will deplete Na
What can you use normal water with when it comes to NG tubes?
flushing tubes, before, between and after medication administration
Disease processes that cause hyponatremia
Cirrhosis fo the liver
Syndrome of Inappropriate Antidiuretic Hormone
Excess secretion of ADH causing hyponatremia
If a person uses plain water enemas, or replenishes after sports with plain drinking water....what will happen?