Fluid and Electrolytes
Exemplars
Dehydration-gastroenteritis-elderly and pediatric
Extracellular fluid volume excess
Chronic renal failure
Homeostasis- when body functions best
Hypertonic- shrinks the cell, water is drawn out (3% sodium chloride/NS commonly used with
ICP and cerebral edema)
Isotonic-balanced flow in and out stays the same (0.9% normal saline, Lactated ringers)
Hypotonic-enlarges cells and they sometimes can burst, water is drawn in, rapid rehydration
(0.45% sodium chloride/ NS)
Intracellular fluid (ICF) is 60% of our body water
Ex; cells are little houses, ICF is what keeps it running/nutrients, so it runs the houses
Extracellular fluids (ECF) 40% total body water, fluid outside of cells, blood plasma
Interstitial fluid is between cells
Cell transport-
Diffusion- high to low movement of solutes
Osmosis- diffusion of water in low to high
Active transport- energy from low to high concentration
Hydrostatic pressure- water is being pushed out causing edema in the tissues
Osmotic pressure- water moving from high to low into the blood vessels which increases BP
Colloidal osmotic pressure- pressure exerted by proteins especially in the blood. Pulling fluid
back into the blood vessels from the extracellular space
Albumin increases BP
Fluid Balance
Impact of Dehydration- old people and babies/kids can suffer greatly
S/S- increased strain on the heart,headache/nausea,fatigue
Encourage fluids,fruits,metabolism and IV fluids
Water leaving the body- sweat,breathing out,urine&feces
Dehydration Vital Signs
High HR
Low BP
, High temp maybe
Vomiting
High RR
Fluid spacing
First spacing- normal distribution of fluid in intracellular fluid AND extracellular fluid
Second spacing- abnormal accumulation of interstitial fluid like EDEMA
Third Spacing-fluid accumulation in the extravascular space (tissues) where water is not easily
exchanged ex; ascites (bad liver failure, stomach is filled with fluid), burns,trauma (car wreck,
fluids leaving the cells), sepsis, LOW BP, use albumin (plasma protein in the blood medication)
to pull fluid back in the blood vessels
Common IV fluids-
Isotonic-0.9% NS, Lactated Ringers
Hypotonic- Dextrose 5%, 0.45% NS
Hypertonic- 3% NS, D5 ½ NS AND D5w but they have to be together
*dont give D5W to head injury pts or infants
Isotonic Solutions-
Normal Saline- go to for rehydration
Uses-IV hydration,Hypotension,sepsis,shock
Caution with-CHF,ESRD,SIADH
Lactated Ringers- substitute for NS, sometimes preferred
Nursing Interventions for giving fluids- watch for fluid overload symptoms, extra heart sounds,
elevated legs for edema
Hypotonic Fluids- swelling cell
0.45% NS
Uses- maintenance fluids, with dextrose, potassium, high BS (DKA)
Caution with- head trauma,burns and liver failure
D5W- 5% dextrose in water
Nursing considerations- don’t administer to head injury pts, at risk for increased ICP (cerebral
edema), monitor for manifestations of fluid volume deficit (s&s- confusion, dizziness, Low BP,
decreased urine output)
Hypertonic Solutions- cell shrinks and wrinkles
3% NS (very salty)
Uses- give for head trauma to reduce swelling ICP, severe hyponatremia
Caution- anything else
Basics of hydration-
Dehydration- sodium is increased, hematocrit (how many RBCs are in the blood) is increased,
urine specific gravity is high
Exemplars
Dehydration-gastroenteritis-elderly and pediatric
Extracellular fluid volume excess
Chronic renal failure
Homeostasis- when body functions best
Hypertonic- shrinks the cell, water is drawn out (3% sodium chloride/NS commonly used with
ICP and cerebral edema)
Isotonic-balanced flow in and out stays the same (0.9% normal saline, Lactated ringers)
Hypotonic-enlarges cells and they sometimes can burst, water is drawn in, rapid rehydration
(0.45% sodium chloride/ NS)
Intracellular fluid (ICF) is 60% of our body water
Ex; cells are little houses, ICF is what keeps it running/nutrients, so it runs the houses
Extracellular fluids (ECF) 40% total body water, fluid outside of cells, blood plasma
Interstitial fluid is between cells
Cell transport-
Diffusion- high to low movement of solutes
Osmosis- diffusion of water in low to high
Active transport- energy from low to high concentration
Hydrostatic pressure- water is being pushed out causing edema in the tissues
Osmotic pressure- water moving from high to low into the blood vessels which increases BP
Colloidal osmotic pressure- pressure exerted by proteins especially in the blood. Pulling fluid
back into the blood vessels from the extracellular space
Albumin increases BP
Fluid Balance
Impact of Dehydration- old people and babies/kids can suffer greatly
S/S- increased strain on the heart,headache/nausea,fatigue
Encourage fluids,fruits,metabolism and IV fluids
Water leaving the body- sweat,breathing out,urine&feces
Dehydration Vital Signs
High HR
Low BP
, High temp maybe
Vomiting
High RR
Fluid spacing
First spacing- normal distribution of fluid in intracellular fluid AND extracellular fluid
Second spacing- abnormal accumulation of interstitial fluid like EDEMA
Third Spacing-fluid accumulation in the extravascular space (tissues) where water is not easily
exchanged ex; ascites (bad liver failure, stomach is filled with fluid), burns,trauma (car wreck,
fluids leaving the cells), sepsis, LOW BP, use albumin (plasma protein in the blood medication)
to pull fluid back in the blood vessels
Common IV fluids-
Isotonic-0.9% NS, Lactated Ringers
Hypotonic- Dextrose 5%, 0.45% NS
Hypertonic- 3% NS, D5 ½ NS AND D5w but they have to be together
*dont give D5W to head injury pts or infants
Isotonic Solutions-
Normal Saline- go to for rehydration
Uses-IV hydration,Hypotension,sepsis,shock
Caution with-CHF,ESRD,SIADH
Lactated Ringers- substitute for NS, sometimes preferred
Nursing Interventions for giving fluids- watch for fluid overload symptoms, extra heart sounds,
elevated legs for edema
Hypotonic Fluids- swelling cell
0.45% NS
Uses- maintenance fluids, with dextrose, potassium, high BS (DKA)
Caution with- head trauma,burns and liver failure
D5W- 5% dextrose in water
Nursing considerations- don’t administer to head injury pts, at risk for increased ICP (cerebral
edema), monitor for manifestations of fluid volume deficit (s&s- confusion, dizziness, Low BP,
decreased urine output)
Hypertonic Solutions- cell shrinks and wrinkles
3% NS (very salty)
Uses- give for head trauma to reduce swelling ICP, severe hyponatremia
Caution- anything else
Basics of hydration-
Dehydration- sodium is increased, hematocrit (how many RBCs are in the blood) is increased,
urine specific gravity is high
