7 Lab Values You MUST KNOW For Every Exam

In this video, we're walking through the seven lab values you need to know for every nursing school exam. I'll give you a super easy breakdown of the lab values you need to know what they are and why they are so important. Let's dive in. Okay, so these are the seven main lab values that you will need to know for every single nursing school exam. Bun, creatinine, hemoglobin, hematocrit, sodium, potassium, and glucose. These are all super important. And I can guarantee that on every nursing exam, at least, at least one of these, perhaps even all of them, will be mentioned. So fully understanding what they are and why they are important is really going to help you critically think through your nursing school exam questions. I'm also going to go through the normal ranges for you for them, but make sure to check with your specific hospital or your clinical site to get their specific standards for lab values, because they can really differ depending on the facility that you are at. Now, I also have a free lab values cheat sheet that I have for you so that you can remember all of the normal ranges when you're at clinical or while you're studying. So I'll put the link to that down below in the description. So be sure to check that out after you watch this video. So the first two that we are going to go through are directly related to the kidneys and how they're functioning. So let's start with creatinine. This is one of the most important kidney labs that you will need to look at. So let's break it down here. Super simple. Creatinine is one of those waste products that the kidneys are responsible for getting rid of. Now remember, the kidneys are responsible for filtering the blood and removing waste all throughout the day. Your muscle cells are constantly building up and breaking down. And creatinine is a byproduct of this natural muscle breakdown. So as it's released, it travels through the blood to the kidneys to be filtered out into the urine. So when we test for creatinine, we're testing for the level of creatinine in the blood. Now, a normal creatinine level is between 0.6 to 1.2 milligrams per deciliter. Now, let's do a little bit of critical thinking to pull it all together here. What do you think will happen to the creatinine level when the kidneys are damaged? Will it go up or down? It will go up. Since the kidneys are damaged, they can't filter that creatinine out of the blood, more and more of it will just build up in the blood. So the creatinine level will increase. Right. And since we know a normal creatinine level is between 0.6 to 1.2 milligrams per deciliter, if that level is higher than normal, I want you to be thinking, hmm, something might be going on with the kidneys, and look into it further. All right, let's move on to the next main kidney lab value that you will want to make sure you understand. It's called blood urea nitrogen, or BUN for short. It's a lot easier. Typically, when you hear of kidney labs being drawn, these two go hand in hand. Creatinine and bun. So we already learned that creatinine is one of the waste products that the kidneys filter out because. But there's another waste product that the kidneys usually filter out, too, and that one is called urea or urea nitrogen. Urea nitrogen is made by the liver as protein is broken down and metabolized in the body. So the liver makes all this urea nitrogen and sends it out into the blood to be filtered by the kidneys. A normal blood urea nitrogen level should be between 7-20mg per deciliter. Now, let's practice those critical thinking skills again. What do you think will happen to the BUN level if the kidneys are damaged? If kidney function declines, the blood urea nitrogen level will start to increase. Right? Since the kidneys aren't able to function as well and excrete as much of it out into the urine as they should. So you'll see that BUN start to increase because it's building up more and more in the blood rather than being excreted into the urine. Makes sense, right? If the kidneys aren't functioning, that urea nitrogen will build up in the blood, and so that BUN level will increase. So again, if you see a BUN that is increased, think about the kidneys and what might be happening with them that could be causing that B1 level to increase in the blood. Now, let's move on to the next two lab values that you will be hearing a lot about in nursing school and on your nursing school exams. Hemoglobin and hematocrit. We also call this the H and H. The hemoglobin value represents the actual number of red blood cells themselves, because the hemoglobin is actually the spot on the red blood cells that carry the oxygen molecule. A normal hemoglobin value is between about 12 to 17.5 grams per deciliter. A hematocrit value tells you how many red blood cells there are in relation to the total blood volume. It is a percentage. So if a normal hematocrit level is around 34 to 52%, which means that out of all the blood and a person has in their body, 34 to 52% of all that blood should be red blood cells. Now, both of these levels can be low for a variety of reasons. Trauma, malformation of the red blood cells, infection, decrease in kidney function, many other reasons. They are essentially measuring how effectively the blood is going to be able to properly circulate oxygen throughout the body. So make sure when you see an abnormal H and H value, you think about what happening with the blood. Now, let's talk about some electrolytes. Electrolytes are a big deal and you have to know a lot about them to pass your exams in nursing school. So I'll give you a quick breakdown of the main ones here. But be sure to print off all of the study guides that we have for you inside the nursing SOS membership community for fluids and electrolytes. We have a full fluids and electrolytes course for you and my friend. It is fantastic. You don't want to miss it, especially if you're having a hard time keeping up with electrolytes and keeping all of them straight. I will put the link down below to the NMC with all the details in the description. The first electrolyte you absolutely must know for your exams is potassium. This is probably the most important electrolyte you need to worry about. It has a very narrow normal range. If it goes out of that range, bad things can happen very quickly. So the normal range of potassium is between 3.5 to 5 mil equivalents per liter. Potassium plays a big role in the body and there are two key things that potassium affects. Okay muscle contraction and it keeps the heart pumping. So potassium has a big effect on the heart. So any shift in potassium level either way should lead you to think about cardiac symptoms that could develop and especially be watching their cardiac conduction through an ecg. So again, when you think of potassium, think muscle contraction, specifically the heart and stable levels. It helps the muscles function and it needs to remain at that small stable level within the body. Now, the second most common electrolyte that you will be hearing and learning about in nursing school is sodium. And a normal sodium level is between 135 to 145 milliliter equivalents per liter. So what does sodium actually do in the body? Well, sodium is vital for helping the muscles contract, and without it, the muscles wouldn't be able to do anything. I like to think of it this way. When there's too much or too little sodium in the body, the muscles are being over stimulated or under stimulated, so they're contracting too much or too little. When you're taking an exam, you can be fairly certain that any altered sodium levels in the body can cause a lot of different kinds of neurological and neuromuscular and cardiac changes. And sodium can cause fluid shifts as well. So making sure that you are considering these things, if you see any abnormal sodium levels, that's critical for your nursing school exams. If you want to dive deep into hypernatremia and sodium levels, be sure to check out this video right here. Now, the next lab value we're going to talk about is the blood glucose level. Now, this is probably one that you have heard of before and maybe even you have a pretty good understanding of, which is fantastic. But we'll touch on it a little more because it is so important to the function of everything in the body. A normal fasting blood glucose level is between 70 to 100 milligrams per deciliter. Now, if a blood glucose level is high or low, it can greatly impact how the body functions. The cells depend on glucose for energy. So if there is too little glucose in the blood, they will not be able to function. And if the glucose is high, the blood can't use it all for energy and it builds up in the blood, leading to hyperglycemia. And this can cause ketoacidosis and damage to the heart and the kidneys and the nerves in the body. Lots of major problems. Now, on the other side of lab values and electrolytes is IV fluids, and you will be tested on these a lot as well. So click on this video here and I'm going to give you a simple breakdown of the types of IV fluids that you need to know about for your exams. And as always, my friend, go become the nurse that God created only you to be. And I will see you over there in that next video.