The 2 Most Common Types of IV Fluids and How They Help
You probably already know you can find IVs with vitamins and medications that address specific health concerns to provide the maximum benefits. But did you know the fluid itself can also do the same?
Different types of IV fluids serve specific purposes. The patient’s health condition will determine the choice of IV fluid. For instance, a fluid that may work well for someone with kidney disease may not be best for a malnourished person.
To better understand how an IV can help you, it’s wise to learn about the various IV fluids. But first, let’s look at why you may need an IV in the first place.
Why Do You Need an IV?
Our bodies run on a finely calibrated system called homeostasis. We achieve this state when our levels of fluids, oxygen, and electrolytes are balanced.
Fluid is necessary because it supplies our cells with the electrolytes they need to function. This happens with fluid moving in and out of cells (from the intracellular to extracellular), also called osmosis. To prevent too much fluid from moving in or out of a cell, the body exerts osmotic pressure to keep a regular, constant, and even flow of fluids.
If our fluid levels are thrown off balance, from sickness or injury, for instance, then we no longer have homeostasis, and our cells won’t receive the electrolytes they need. An IV replenishes those fluids and helps restore homeostasis.
There are two main types of IV fluids: crystalloids and colloids. In a crystalloid solution, the particles in the fluid are tiny enough to pass through the semi-permeable cellular membranes. In colloid IV solutions, the molecules are too big to cross the membranes. This allows the fluid to stay in your bloodstream rather than entering the cells.
Crystalloid solutions are popular because they are shelf-stable, readily available, fairly cheap to manufacture, and carry no allergy risk. There are three kinds of crystalloid solutions, categorized by their tonicity, or how they move in and out of cells via osmosis.
Hypotonic IV Solutions
A hypotonic IV moves from the bloodstream (or extracellular space) to the intracellular. If cells are lacking fluids, this IV type remedies that condition. For instance, people with diabetic ketoacidosis may need a hypotonic IV to counteract cellular dehydration.
Hypotonic IV fluids include the following:
- 0.45% NaCl
Like other hypotonic solutions, this one has a low concentration of sodium chloride or saline. That’s why it’s often used to treat patients with high sodium levels in their bodies, a condition called hypernatremia. People who have heart or renal failure or those with edemas should avoid this solution. The 0.45% NaCl solution can also cause excessive fluid in the body, leading to edemas or diluted electrolyte levels in the body.
- 0.33% NaCl
This solution is often for patients whose kidneys don’t function properly and can’t retain water as they usually would. Like 0.45% NaCl, this IV isn’t for people with heart or severe kidney problems. It can also cause pulmonary edemas.
- 0.225% NaCl
With the lowest amount of saline, this solution is typically reserved for children for health maintenance. It should be combined with dextrose, which is a form of glucose or sugar.
- 2.5% dextrose in water
This solution helps alleviate dehydration while also lowering the body’s potassium and sodium levels.
Hypertonic IV Solutions
“Hyper” is the opposite of “hypo;’” therefore, hypertonic IVs have the opposite effect of hypotonic ones. Instead of bringing water into the cells, they take water out.
Hypertonic solutions are best for people who lack the necessary sodium. Hypertonic IVs are generally designated for short-term use until electrolytes are re-balanced, as patient’s carry the risk of pulmonary edema from too much fluid. People with dehydration, coupled with heart or kidney problems, should avoid these IVs.
The following are hypertonic IVs:
- 3% NaCl
- 5% NaCl
- Dextrose 5% in 0.45% NaCl
- Dextrose 5% in 0.9% NaCl
- Dextrose 5% in Lactated Ringer’s
Lactated Ringer’s is a solution containing sodium chloride, potassium chloride, calcium chloride, and sodium lactate.
- 10% Dextrose in water
Unlike many other IVs, this one does not have electrolytes.
- 20% Dextrose in water
- 50% Dextrose in water
Isotonic IV Solutions
These IVs mimic the volume of particles in blood plasma. As a result, they don’t draw fluid into or out of the cells but rather maintain a balance between the two.
The following include isotonic IVs:
- 0.9% NaCl
This is a common IV fluid, also known as normal saline solution. It’s used to treat dehydration caused by a range of issues, such as vomiting, diarrhea, and hemorrhage.
- Lactated Ringer’s
Helpful for people with burns or traumatic injuries, Lactated Ringer’s also helps with acute blood loss. People with renal failure or those with liver disease who cannot metabolize lactate–one of its ingredients–should avoid this solution.
- 5% Dextrose in water
This is a rare solution that is both isotonic and hypotonic. Calories in this IV help provide short-term nourishment and deliver water to help the kidneys function.
- Ringer’s Solution
This is just like Lactated Ringer’s, minus the presence of lactate.
This is a solution that can be infused with red blood cells. It very closely resembles the electrolyte levels in blood plasma.
Colloid IV Fluids
Because the particles in colloid solutions are too large to enter the intracellular areas, the fluid expands the blood plasma. Patients don’t need as much of this solution compared to crystalloid IVs, so these solutions are ideal for people who can’t handle large volumes of fluid. Colloid IVs are helpful for people who are malnourished.
Below are some colloid IVs:
- Albumin 5%
- Albumin 25%
Albumin is a protein produced by the liver. It’s good for providing protein to patients, as well as stabilizing the blood flow from the heart in people who are in shock.
- Low-molecular-weight dextran
- High-molecular weight dextran
Get the Right IV for You with Mobile IV Nurses
We use our medical expertise to provide a wide variety of mobile IV services. Mobile IV Nurses offers two types of IV fluids: 0.9% NaCl (normal saline) and Lactated Ringer’s, both of which are isotonic crystalloid solutions. Available at affordable prices, both IV types are customizable with a range of add-on supplements and medications. Contact us today to learn more about our mobile IV services and how we can help you.