Question

You hook up an IV for someone and can give them either 5% dextrose or normal saline (doesn't matter which). What is the osmolality of the IV?

(A) Hyperosmolar
(B) Hypoosmolar
(C) Isosmolar
(D) Anisosmolar

Answer 1

IV solutions like 5% dextrose or normal saline are isosmolar with body fluids, having an osmolarity close to 300 mOsm, which is designed for patient safety and maintaining fluid balance within the body.

Step-by-step explanation:

When considering the osmolality of intravenous (IV) fluids such as 5% dextrose and normal saline, it is important to recognize that these solutions are formulated to be isosmolar with the body's fluids. Typically, the body's osmolarity is about 300 mOsm. Solutions like 0.9% saline and 5% dextrose are designed to match this osmolarity to ensure that red blood cells maintain their normal volume, thus avoiding damage caused by too much water entering (hypotonic solutions) or leaving (hypertonic solutions) the cells.

So, when considering if an IV solution of either 5% dextrose or normal saline is hyperosmolar, hypoosmolar, isosmolar, or anisosmolar with regard to body fluids, the answer is (C) Isosmolar. These IV solutions have solute concentrations designed to mimic the osmotic balance of the blood, making them safe choices for rehydration and maintaining fluid balance in the body.