Intravenous Fluids Flashcards
What is the recommendation for treating hyponatremia?
Use normal saline or 3% saline, depending on the severity and symptoms.
What should be done if sodium levels rise too quickly?
Use a hypotonic solution like D5 half-normal saline to level off sodium.
What does D5W stand for?
5% dextrose in free water.
What are IV fluids used for?
To maintain blood pressure, hydration, and electrolyte balance.
What are the two types of IV fluids?
Crystalloids and colloids.
What are crystalloids?
Molecules small enough to pass through a blood vessel membrane.
What are colloids?
Large molecules, like albumin, that generally do not pass through blood vessel membranes.
What are the two fluid compartments of the body?
Intracellular fluid space and extracellular fluid space.
What does the extracellular fluid space consist of?
Intravascular volumes within blood vessels and interstitial fluid.
How is total body water content calculated?
Extracellular fluid plus intracellular fluid.
What is osmolality?
The amount of ions or content of a fluid, normal is 280 osmoles.
What is diffusion?
Movement of fluid from one space to another without a semipermeable membrane.
What is osmosis?
Fluid movement past a semipermeable membrane, like a cell membrane.
What is isotonic fluid?
Fluid with similar plasma osmolality as serum, around 280 osmoles.
What is hypotonic fluid?
Fluid with osmolality less than plasma osmolality (less than 280 osmoles).
What is hypertonic fluid?
Fluid with osmolality greater than plasma osmolality (greater than 280 osmoles).
What is the osmolality of D5W?
278 osmoles, slightly hypotonic.
What is normal saline composed of?
150 mEq of sodium and 154 mEq of chloride, making it isotonic.
What is the osmolality of normal saline?
286 mOsm/kg, slightly hypertonic but close to plasma osmolality.
What is half-normal saline?
Contains 77 mEq of sodium and 77 mEq of chloride, isotonic with 143 mOsm.
What does D5 half-normal saline contain?
77 mEq of sodium, 77 mEq of chloride, and 50 mEq of dextrose.
What is the characteristic of D5 half-normal saline?
It is slightly hypotonic due to rapid consumption of dextrose by the body.
What is the composition of 3% normal saline?
Contains over three times the sodium and chloride of normal saline, hypertonic.
What does lactated Ringer’s solution contain?
Contains 130 mEq of sodium, 4 mEq of potassium, 109 mEq of chloride, 28 mEq of bicarbonate, and 50 mEq of dextrose.
What is the osmolality of lactated Ringer’s solution?
Around 272 mOsm/kg, slightly hypotonic but generally isotonic.
When should you use D5W or D50?
For hypoglycemia, especially if the patient has had too much insulin.
What is recommended for hypotension?
Use isotonic solutions like lactated Ringer’s or normal saline.
What to do if a patient is hyponatremic and seizing?
Use 3% saline but do not increase sodium more than 10 mEq in 24 hours.
