IV fluids
What is involved in the solution of hypertonic solutions
Adds calories to Na, electrolytes or water. D50 used in severe hypoglycemia.
Hypertonic considerations
Are used as volume expanders. Hypertonic solutions affect renal filtration mechanisms and can cause hypervolemia. Used for patients with Severe hyponatremia and patients with cerebral edema; will raise Na in bloodstream while osmosis removes water from intracellular space causing volume expansion.
Hypotonic solutions
Hypotonic solutions contain less solute then blood does, which causes water to want to leave the hypotonic solution and enter an area that has a higher concentration of solute via osmosis. When discussing IV fluids, that usually means that the water will want to leave the intravascular space and enter Red Blood Cells (RBCs).
Hypotonic solutions
Hypotonic solutions have an electrolyte content of less than 250 mEq/L and are administered to expand the intracellular space. They are commonly infused to dilute extracellular fluid and rehydrate the cells of patients who have hypertonic fluid imbalances and to treat gastric fluid loss and dehydration from excessive diuresis. This type of solution provides free water, sodium, and chloride but does not provide calories or other electrolytes.
Isotonic solutions
Isotonic solutions have an approximate electrolyte content of 300 mEq/L. This type of solution is infused to replace fluid losses, usually extracellular losses, and to expand the intravascular volume. Most isotonic solutions do not provide calories or free water.
Why are isotonic solutions given
Normal Saline is given to increase the amount of fluid in the blood vessels (intravascular space), without significantly changing the balance of electrolytes in the body. This is useful for making sure a patient remains in a well-hydrated state of homeostasis.
Why would you give a hypotonic solution
Probably the most common reason to give 0.45% Saline is for true dehydration, which is when the body has lost water only, without losing any electrolytes (this is different from fluid volume deficit, when the body loses BOTH water AND electrolytes). In dehydration, the body already has a normal amount of electrolytes, so there is no need to provide more in the IV solution. The patient simply needs some of their water replaced!
hypertonic solutions
Solutions with an electrolyte content of 375 mEq/L or more are considered hypertonic. Hypertonic solutions are infused to treat patients who have severe hyponatremia. Depending on the type of hypertonic fluid infused, it can provide patients with calories, free water, and some electrolytes
Hypotonic considerations
These solutions will hydrate cells, although their use may deplete fluid within the circulatory system.treats intracellular dehydration (DKA, hyperosmolar hyperglycemia); shifts fluid from vascular bed into cells and interstitial spaces. Can worsen hypovolemia and hypotension; can cause vascular collapse; monitor for volume deficit; older adults may show confusion or dizziness. NEVER give to increased ICP, liver disease, trauma or burns due to potential for hypovolemia.
When are hypertonic solutions used
They can be used for patients that have edema because they have higher osmolality than cells so the water comes out of the cell into the veins and thus is forced out by the kidney into the urine. Hypertonic solutions can also be used for patients with hypertension because it increases blood volume by pulling water into the vessels.
define hypertonic solutions
They have more solutes than blood
Define Isotonic fluids
a solution in which body cells can be bathed without net flow of water across the semipermeable cell membrane; also, denoting a solution having the same tonicity as another solution with which it is compared.
Caution for hypertonic solutions
give slowly to avoid fluid overload and pulmonary edema. Store hypertonic NaCl solutions away from other floor stock and monitor for s/o hypervolemia due to fluid shifts; Do not give to renal or cardiac conditions who are dehydrated; Do not give to pts with cellular dehydration such as DKA (diabetic ketoacidosis).
Examples of Hypotonic solutions
•0.45% Saline •*5% Dextrose in Water (this is technically isotonic, but once the dextrose is absorbed then it acts on the body as if it were hypotonic)
List of isotonic solutions
•0.9% Saline (aka Normal Saline) •Ringer's Solution •Lactated Ringers •5% Dextrose in 0.225% Saline •5% Dextrose in Water (technically, Isotonic, but physiology hypotonic...I'll explain in a minute)
Examples of hypertonic solutions
•10% Dextrose in Water •3% Saline •5% Dextrose in 0.45% Saline •5% Dextrose in 0.9% Saline