Hey everyone, it's Nurse Sarah with RegisteredNurseRN.com and in this video I want to do a quick review over colloids versus crystalloid solutions. So let's get started. Both of these solutions are administered IV, so to that intervascular space and both of these solutions expand our plasma volume. Now whenever I say expand plasma volume what I'm talking about is that we are adding more fluid to that intervascular space.
So we're adding more fluid into our blood vessels. So first let's take a look at colloid solutions. These solutions can include natural and synthetic type solutions.
For instance, a natural type of colloid is known as albumin, whereas we can have synthetic types which includes dextran, hydroxy ethyl starches, and gelatin. And how these fluids work is that they are going to pull water into that intravascular space. Now how do they do this?
Well, whenever you're administering a bag of colloids, inside that bag you have very, very large molecules. So whenever those molecules go inside the intravascular system, they are unable to actually escape that capillary wall because they're just so big. So because they can't escape that capillary wall, high concentrations of them hang out inside the intravascular system.
So whenever we have a high concentration of something hanging out in there, what's going to happen is that that's going to increase oncotic pressure. Another term for oncotic pressure is known as colloid or colloidal osmotic pressure. And this results in water being pulled from around that blood vessel. So from that interstitial fluid.
So water is going to be pulled inside that blood vessel, hence our intervascular space. And it's going to expand the volume, hence the fluid inside that vessel. And this is something we definitely want whenever our patient is experiencing hypovolemic shock, severe burns, or they've had some type of severe bleeding. And because how these fluids work, they are fast at expanding this plasma volume because they have such a great effect at pulling that water across that capillary wall into the intravascular space. So the amount administered, so the amount of colloids we give the patient is usually equal to the amount of fluids that the patient has lost.
So we don't have to just throw in a bunch. of colloids to this patient. Now there are some downsides to these fluids.
Two things. big things is that they can have allergic reactions and coagulation problems with these solutions. So we really have to monitor for that as the nurse.
Plus they're not as easily accessible and they tend to cost more. Now let's compare this to crystalloid solutions. So crystalloids, they include hypertonic, hypotonic, and isotonic solutions.
So in these bags of fluid, we have fluid, but we also have electrolytes and they are smaller molecules. Whereas with colloids, Those are big molecules, typically like proteins, but these are electrolytes. Therefore, because they're smaller, they don't hang out as long in that intravascular space.
And because of this, the patient is going to need high amounts of these fluids in order to replace the amount of fluid they have lost. So they really carry a huge risk with fluid volume overload. And these fluids can work in a variety of ways, depending on the tonicity of the bag of fluid. For instance, whenever we're dealing with hypertonic crystalloid solutions, we have a high tonicity.
So there's a high amount of solutes in that bag of fluid compared to the tonicity or the osmolarity of your blood plasma. So when we throw a hypertonic solution into that intravascular space, what it can do is that it can pull water from the cells and dehydrate them, which sometimes we need to do that if we have like cell swelling like with cerebral edema. However, on the flip side, hypotonic solutions work in an opposite way. They, in this bag of fluid, they have a lot of fluid, but they don't have a lot of solutes. So it has a lower osmolarity, hence tonicity, than compared to your blood.
So whenever you throw those fluids into that intravascular space, Heterovascular space it can cause water to go inside of the cell which sometimes is what we need when that cell is dehydrated But sometimes they can cause problems because it can cause that cell to swell and rupture and then we have isotonic Fluids and I so just means equal so that bag of fluid its tonicity has the equal amount of solutes compared to your blood so it's the same type of tonicity. So whenever we put that isotonic solution into the blood, it doesn't really cause this mass movement of fluid in and out of the cell. It really is just going to expand that intravascular space.
And all of this is happening because of osmosis. Now, some good things about crystalloid solutions that unfortunately colloid solutions did not have is that crystalloid solutions do not cause allergic reactions. or coagulation problems.
Plus, they are easily accessible. You can typically go in your clean hold and get whatever type of fluid you want based on what the doctor ordered. And they tend to cost less, which is really good for the patient.
Okay, so that wraps up this video. If you'd like to watch more in-depth lectures over IV solutions, cell transport, and other fluid electrolyte topics, you can access the link in the YouTube description below.