Abstract
Infusion therapy specialists are recognized for their technical expertise and their knowledge of the anticipated reactions and adverse effects of many complicated therapies. But when asked the rationale for intravenous fluid selection, many infusion nurses can only shrug their shoulders. Although intravenous fluid selection may seem a complex principle, it is really quite simple. Once the flow of body fluids among fluid compartments is understood, it is easy to follow the intended path of IV fluids. But infusion specialists should be cautious of the manner in which IV fluids are categorized prior to infusion (isotonic, hypotonic, and hypertonic) because these are not always consistent with how they react in the body.