ATI TEAS (Test of Essential Academic Skills) Version 7ScienceMedium
A patient is admitted to the emergency department with severe dehydration. The medical team decides to administer an intravenous (IV) fluid that has a higher solute concentration than the patient's blood plasma. Which of the following terms best describes this type of IV fluid?
- AIsotonic
- BHypotonic
- CNormotonic
- DHypertonic
Show answer & explanationAnswer & explanation
Correct answer: D. Hypertonic
A hypertonic solution has a higher solute concentration than the body fluids, such as blood plasma. When administered intravenously, it causes water to move out of the cells and into the extracellular fluid to dilute the higher solute concentration, which can be useful in certain clinical situations like severe dehydration with cerebral edema.
Why the other options are wrong
- A. Isotonic solutions have the same solute concentration as body fluids; they do not cause net fluid shift.
- B. Hypotonic solutions have a lower solute concentration than body fluids; they cause water to move into cells.
- C. Normotonic is not a standard term for describing tonicity; isotonic is the correct term for equivalent concentration.
Hypertonic Solution
A solution that has a higher solute concentration than another solution, typically referring to body fluids like blood plasma.
- Causes water to move out of cells.
- Cells will shrink or crenate.
- Used clinically to reduce edema or increase blood volume.
Memory trick: Hyper-tonic solutions make cells 'hyper-shrink'.