Breaking Down IV Fluids: The 4 Most Commonly Types and Their Uses

iv fluids

In most nursing programs there is at least one lesson on intravenous (IV) hydration. If you are like many nurses, the information may have gone into your brain, you spit it out on paper, and then promptly forgot what you had learned! If this sounds like you, you’re in luck, because this article will refresh your memory on the four most common types of IV fluids, their components, and their common uses!

First, lets re-explore why IV fluids are administered in the first place. You may remember from your schooling that the body is made up of approximately 60% water! Up to 2/3 of this water is stored intracellularly. When a patient enters the hospital, whether for an illness or pre-operatively for a surgery, hydration status is often one of the first things that is addressed. There are many different types of IV fluids that a physician may choose from, depending on the patient’s history and current diagnosis! Solutions are most often either crystalloids or colloids. Crystalloids have small particles that can pass easily back and forth over cellular membranes, and are either hypertonic (more particles in the solution than in the plasma), hypotonic (less particles in the solution than in the plasma), or isotonic (roughly the same amount of particles in both the solution and the plasma). Colloids, alternatively, have large particles that remain in the extracellular space and therefore draw water out of the cells into the plasma. This article will focus on crystalloids, as they are the most commonly ordered. Here are four of the IV fluids you are most likely to see ordered for your patient, and their common uses:

  1. 1

    9% Normal Saline ( also known as NS, 0.9NaCl, or NSS)

    normal saline
    Less commonly, this solution is referred to as physiological saline or isotonic saline

    This is one of the most common IV fluids because it works for most hydration needs due to vomiting, diarrhea, hemorrhage, or even shock. It’s the fluid of choice for resuscitation efforts as well. NS is also the only fluid used in conjunction with blood product administration. It is an isotonic crystalloid that contains 0.9% sodium chloride (salt) that is dissolved in sterile water. It is sometimes used with caution or even avoided in patients with cardiac or renal compromise because of the sodium causing fluid retention that may put extra stress on the heart or kidneys.

  2. 2

    Lactated Ringers (also known as LR, Ringers Lactate, or RL)

    This solution is an isotonic crystalloid that contains sodium chloride, potassium chloride, calcium chloride, and sodium lactate in sterile water. It is the most similar to the body’s plasma and serum concentration, and is especially great for burn victims or those with hypovolemia due to fluid shifts. It is avoided in patients with liver disease because the liver may not be able to efficiently process the lactate. Watch the following video if you want to learn more about LR.

  3. 3

    5% Dextrose in Water (also known as D5 or D5W)

    Is an isotonic carbohydrate (sugar) solution that contains glucose (sugar) as the solute. When this is absorbed, the glucose is usually quickly grabbed up by cells and utilized for energy, leaving only water which is then a hypotonic solution. One interesting fact is that this solution provides 170 calories per liter, and is often used for diabetic patients who are nothing by mouth for various reasons. It is avoided in patients with renal failure, cardiac compromise, or those who are at risk for increased intercranial pressure. This is because it can sometimes lead to fluid overload in cardiac and renal patients, and cerebral edema those with intercranial pressure issues. Here is a short animation that explains consequences of fluid overload for tissues.

  4. 4

    45% Normal Saline (also known as Half Normal Saline, 0.45NaCl)

    This is a hypotonic crystalloid solution of sodium chloride dissolved in sterile water (unlike 0.9% Normal Saline which is isotonic, as mentioned above). This fluid is designed to treat cellular dehydration, caused by such conditions as hypernatremia or diabetic ketoacidosis. It is always avoided in patients with burns, trauma, or liver disease because of its tendency to deplete intravascular fluid levels. Infusing half normal saline, causes water to shift from the extracellular fluid compartment to the ICF compartment.

It is important for all nurses to understand why their patient has specific orders in place, and how it affects their overall treatment plan.

This quick list should assist with providing a basic understanding of the common IV fluids you are hanging for your patients, so that you can provide the education and advocacy necessary for your patients’ hydration needs.