Why is osmolality important in tube feeding?
The osmolality of an enteral formula is an important consideration in terms of tolerance. Osmolality is the number of molecules and ions per kilogram of a solution. It may be easier to think of osmolality as the number of particles per kilogram of water.
What is the most common electrolyte imbalance associated with enteral feeding administration?
Defined as potassium serum blood levels below 3.5 mEq/L, hypokalemia is a common electrolyte imbalance, and GI loss is the most common cause.
What is a hypertonic tube feeding?
Hypertonic Formulas If the enteral formula has an osmolality greater than that of the body fluid it is considered a hypertonic formula. Hypertonic formulas create an osmotic gradient that attracts water from the body into the lumen of the GI tract.
What high osmolality formula may cause?
Formula with a higher osmolality than that of normal body fluids produces an osmotic effect in the stomach and small intestine; this hyperosmolality draws water into the GI tract to dilute the concentration of the formula. An influx of water into the GI tract may cause diarrhea, nausea, cramping, and distention.
Are osmolarity and osmolality the same?
Osmolarity and osmolality are frequently confused and incorrectly interchanged. Osmolarity refers to the number of solute particles per 1 L of solvent, whereas osmolality is the number of solute particles in 1 kg of solvent. Osmolality has the units of Osm/kg H2O.
What is the optimal osmolality of a normal diet tube feeding?
The osmolality of full-strength isotonic formulas is similar to the osmolality of normal body fluids, approximately 300 mOsm/L.
What is an isotonic tube feeding formula?
Isotonic means that a formula is within the normal physiologic range, approximately 300 mOsm/kg of water. Generally, tolerance problems are minimized by using an isotonic formula.
Can a high osmolality formula cause diarrhea?
High-osmolality formulations can contribute to diarrhea, especially when delivered into the small bowel. Diarrhea in the tube fed patient has many causes. Typically, it is not the tube-feeding formula itself, as most are lactose-free and have lower osmolality.
Are there fluid and electrolyte disturbances associated with tube feedings?
FLUID AND ELECTROLYTE DISTURBANCES ASSOCIATED WITH TUBE FEEDINGS Tube-fed patients tend to have the fluid and electrolyte dis- turbances associated with their underlying disease and treatment conditions. Theoretically, then, it should be pos- sible to observe all types of electrolyte disturbances in tube- fed patients.
How does osmolality affect the renal solute load?
A formula’s osmolality affects the renal solute load and thus the water requirements. Renal solute load can be defined as the sum of substances that must be excreted by the kidneys (such as urea, potassium, sodium, and chlo- ride). A high renal solute load (created by nutrient use) requires a large water volume for excretion.
What is the normal plasma osmolarity for large animals?
The normal plasma osmolarity for solutions to be administered to large animals is approximately 306 mOsm/L; solutions can therefore be defined as isotonic (300–312 mOsm/L), hypertonic (>312 mOsm/L), or hypotonic (<300 mOsm/L).