09 Fluids & Electrolytes {Pathophysiology} Flashcards
Each compartment in the body has a particular composition of electrolytes, which differs from that of their compartments. To function normally, ______ _______ must have fluids and electrolytes in the right compartments and in the _____ ______.
body cells
right amounts
Whenever an electrolyte moves out of a cell ___________.
another electrolyte moves in to takes its place.
The number of cations and _______ must be ______ to have _______.
The number of cations and anions must be the same to have homeostasis to exist.
Intravascular compartment
fluid inside a blood vessel
Intracellular compartment
all fluid inside the cell
Most body fluids are
inside the cells
Extracellular compartments are
the interstitial fluid (fluid BETWEEN cells) often called third space, blood, lymph, bone, connective tissue, water and transcellular fluid
Third spacing
the accumulation and sequestration of trapped extracellular fluid in an actual or potential body space as a result of disease or injury; considered a volume loss and is unavailable for normal physiological processes
Edema
an excessive accumulation of fluid in the interstitial space; occurs as a result of alterations in oncotic pressure, hydrostatic pressure, capillary permeability and lymphatic obstruction
localized edema
occurs as result of traumatic injury for accidents or surgery, local inflammatory processes or burns
generalized edema (also called anasarca)
is the result of extra fluid throughout the body and is a result of conditions such as cardiac, renal, or liver failure
Total body fluid (intracellular and extracellular)
60% of weight in adult
55% in older adults
80% in infants
Who is at higher risk for fluid related problems?
infants and older adults due to their higher and lower percentages of body fluids
Osmotic pressure
a pull that draws water through a membrane to a more concentrated side, or side with more solute; it is caused by this imbalance in solutes
filtration
the movement of solutes and solvent by hydrostatic pressure
hydrostatic pressure
the force exerted by the weight of a solution
At the ______ ______ of the capillary, the hydrostatic pressure is _______ than the osmotic pressure; therefore fluids and diffusible solute move _____ of the capillary.
arterial end
higher
out
At the _______ ______, the osmotic pressure or _____, is higher than the hydrostatic pressure and fluids and some solutes move _______ the capillary.
venous end
pull
out
What happens to the excess fluid and solutes taht remain in teh interstitial space?
They are returned to the interstitial space by the lymph channels.
Osmolality
the number of osmotically active particles per kilogram of water; also known as the concentration of a solution
What is the normal osmolality of plasma?
270-300 milliosmoles/kg (mOsm/kg)
What happens with an individual has diarrhea?
the body loses more electrolytes that it does fluids and it creates an environment where the extracellular fluid contain fewer electrolytes or less solutes than he intracellular fluid
The thing to remember about electrolyte/solute equilibrium
fluids and electrolytes must be kept in balance for health; when they remaine out of balance, death can occur
isotonic solutions
the solution on both side of a selectively permeable membrane have established equilibrium or have an equal concentration; very little osmosis will occur
hypotonic solutions
when a solution contains a lower concentration of salt or solution than another solution
hypotonic solutions have fewer solutes than the cell so osmosis or the pulling in of the solution into the cell would occur
hypertonic solutions
a solution that has a higher concentration of solutes than another, less concentrated solution; have a higher osmolality than body fluids
a hypertonic solution would draw fluid out of the cells and into the interstitial or vascular space
osmotic pressure
the amount of osmotic pressure is determined by the concentration of solutes in solution
A ________ solution has less solutes than the cells
A ________ solution has more solutes than the cells
A ________ solution has the same amount of solutes as the cells
hypotonic
hypertonic
isonoinc
Substance that are moved through active transport
sodium
potassium
calcium
the amount of water released by metabolism of each 100 calories of fat, carbohydrates, or protein
10 mL of water
insensible water loss
loss through skin (about 100 mL per day)
loss from the lungs (varies)
water balance related to the gastrointestinal tract
large quantities of electrolyte-containing liquids are secreted into the GI tract but almost all of this fluid is reabsorbed unless there is severe diarrhea; in this case large quantities of fluid and electrolytes are lost
kidneys
play a major role in regulation of fluids and electrolytes and excrete the largest amount of fluids; normal kidneys can adjust the amounts of water and electrolytes leaving the body
adrenal glands in fluid volume homeostatis
the adrenal glands (that sit atop the kidneys) secrete aldosterone which aids in the control of extracellular fluid volume by regulating the amount of sodium that is reabsorbed by the kindneys (look up more info on this!!)
the effect of the pituitary gland (located in the brain) on fluid homeostasis
the pituitary gland regulates the osmotic pressure of extracellular fluid through the release of antidiuretic hormone that helps in the regulation of the amount of water that is reabsorbed by the kindneys`
What is the GOAL of TX in fluid volume deficient?
to restore fluid volume, replace electrolytes as needed and eliminate the cause of the fluid volume deficit
Three types of fluid volume deficit
isotonic dehydration
hypertonic dehydration
hypotonic dehydration
isotonic dehydration
water and electrolytes are lost in equal proportions
it is known as hypovolemia and is the most common type of dehydration
results in decreased circulating blood volume and inadequate tissue perfusion
hypertonic dehydration
water loss exceed electrolyte loss (the serum osmolality is too high)
problems occur from alteration in concentration of specific electrolytes
moves from the intracellular compartments into the plasma and interstitial fluid spaces causing the cells they be dehydrated and shrink
hypotonic fluid volume deficits
electrolytes exceed water losses (to few electrolytes)
clinical problem occur as a result from fluid shifts between compartments, causing a decrease in plasma volume
fluid moves from the plasma and interstitial space into the cells, causing a plasma volume deficit causing cells to swell
causes of isotonic dehydration
inadequate intake of fluids and solutes
fluid shifts between compartments
excessive losses of isotonic body fluids
causes of hypertonic dehydration
conditions that increase fluid loss; excessive perspiration, hyperventilation, ketoacidosis, prolonged fevers, diarrhea, early-stage kidney disease and diabetes insipidus
causes of hypotonic dehydration
chronic illness
excessive flid replacement (hypotonic)
kidney disease
chronic malnutrition
In general isotonic dehydration is treated with _________ fluid solutions, hypertonic dehydration is treated with _______ fluid solutions and hypotonic dehydration is treated with _______ fluid solutions.
isotonic
hypotonic
hypertonic
Fluid volume excess is also called
overhydration or fluid overload
Types of fluid volume excess
isotonic overhydration (known as hypervolemia)
hypertonic overhydration
hypotonic overhydration
isotonic overhydration
known as hypervolemia is excessive fluid in the extracellular fluid compartment; shifting does not occur and it causes circulatory overload and interstitial edema; pulmonary edema may occur
hypertonic overhydration
is rare and is caused by excessive sodium intake; fluid is drawn from the the intracellular fluid compartment; the extracellular fluid volume expands and the intracellular fluid volume contracts
hypotonic overhydration
also known as water intoxication; excessive fluid moves into the intracellular space, and all body fluid compartments expand; electrolyte imbalances happens as a result of dilution
causes of isotonic overhydration
inadequately controlled IV therapy
kidney disease
long-term corticosteroid therapy
causes of hypertonic overhydration
excessive sodium ingestion
rapid infusion of hypertonic saline
excessive sodium bicarbonate therapy
causes of hypotonic overhydration
early kidney disease
heart failure
syndrome of inappropriate antidiuretic hormone secretion
inadequately controlled IV therapy
replacement of isotonic fluid loss wit hypotonic fluid loss
irrigation of wound and body cavities with hypotonic fluids
