In this instructional YouTube video, the presenter walks nursing students through the three core renal laboratory values—glomerular filtration rate (GFR), serum creatinine, and blood urea nitrogen (BUN)—that are essential for understanding kidney function and for exam preparation. She begins by emphasizing the kidneys’ role as the body’s primary filter and offers a free downloadable cheat‑sheet of normal lab ranges. For each lab value she defines what it measures, provides the normal reference range, explains how the value changes when kidney function declines (including the effect of aging on GFR), and inserts a “critical‑thinking point” that prompts learners to predict the direction of change and consider compensatory mechanisms. The video also includes a shout‑out to a viewer comment, promotes a paid membership course for deeper renal‑disorder study, and ends with a call‑to‑action to subscribe and watch the next video on study strategies. The overall purpose is to give a concise, memorable framework for interpreting renal labs and to encourage active learning through questioning.
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In this video, we're diving into the renal lab values that you must know for nursing school. The kidneys are a big deal and you will be tested on them a lot in nursing school, but it can be kind of tricky to learn how it all works. So I'm going to give you an easy breakdown of the renal labs you absolutely must know, along with some critical thinking points to help you understand how it all fits together. I'm going to give you all all the answers. So hit that subscribe button and click the notification bell and let's dive in. The first thing you need to understand about the kidneys is that they are one big filter. It's their job to filter out and get rid of waste products and excess fluid from the body. Without the kidneys, toxic waste products would just build up in the blood and cause a lot of problems. And it's super important for you to know how to tell when something is wrong with the kidneys and what it all means. So let's walk through the lab values you'll need to look for. Now don't worry, I have a free lab values cheat sheet to give you that has all the normal ranges listed for the most common lab values that you need to know about in nursing school. We'll put the link down below in the description for you to download it. Be sure to print it off for clinical because it will be super helpful for you. So the first lab value we'll talk about is the GFR or glomerular filtration rate. The GFR is the amount of blood the glomeruli, which are little filters inside the kidneys, can process in one minute. When the glomerular filtration rate is good, somewhere between 90 to 125 milliliters per minute is considered normal. That means that the glomeruli are filtering 90-125ml of blood every minute. But if the kidneys are damaged, that number will start to decrease since they can't filter as much or as fast as usual. Now, it's also important to point out that the GFR will naturally decrease with age, so an older patient will naturally have a lower gfr. So that needs to be taken into consideration as well. Now here's a critical thinking point that I want you to remember. If the kidneys are damaged and some of the glomeruli aren't able to filter as much, the remaining healthy glomeruli will step up their game and try to compensate. So if you have a patient whose kidneys are compromised, you might notice that their GFR is still within normal range, even though the kidneys are damaged. Now, as the damage continues and more glomeruli can't function, you'll see that GFR start to decline. If you're a nursing SOS member and want to know more about kidney function and renal disorders, head on over to your membership dashboard and check out the renal GU course that we have for you. In there, I walk you through all of the disorders and help you to critically think through them all. It's super helpful, especially as you go to take your exams. Now, let's talk about creatinine. This is one of the most important kidney labs that you'll need to look at. Creatinine is one of those waste products the kidneys are responsible for getting rid of. 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. So here's your critical thinking point. What do you think will happen to the creatinine level when the kidneys are damaged? Will it go up or down? Now, I'll give you a minute to think about it. I know you can do will go up. Since the kidneys are damaged and they can't filter that creatinine out of the blood, more and more of it will just build up in the bl. So the creatinine level will increase. A normal creatinine level is between 0.6 and 1.2 milligrams per deciliter. So if that level is higher than normal, I want you to be thinking there might be something happening with the kidneys and then look into it further. Now, the next lab value is another super important kidney lab, but before we get there, I want to give a shout out to Julie for our YouTube comment of the week, which says, I love the way you explained it. Made it so much easier to understand. Thank you. Yay. I'm so happy it all just finally clicked for you, Julie. I know learning so much in nursing school in such a short amount of time can be tough, so I'm glad that we can help condense it for you and explain it all in a way that makes sense. That is what we're here for now. I love reading your comments. Each and every week, friend, they make me very happy and I feel so blessed to have your support. So thanks for being here. Now, as promised, the next lab value we'll talk about is another really important renal lab. This one's called blood urea nitrogen, or BUN for short. Typically, when you hear of kidney labs being drawn, these two go hand in hand. Creatinine and bun. So along with creatinine, there's another waste product that the kidneys usually filter out, and that one's 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? Go ahead and think about it for a second. If kidney function declines, the blood urea nitrogen level will start to increase since the kidneys aren't able to function as well and excrete as much of it out into the urine. So as the glomerular filtration rate slows down, you'll see the BUN start to increase because it's building up more in the blood rather than being excreted out into the urine. Make sense? If the kidneys aren't functioning, that urea nitrogen will build up in the blood and so the BUN level will increase. Now remember that creatinine and BUN do the opposite of gfr. If the kidneys are damaged, the creatinine and BUN levels will increase, but the GFR will decrease when the kidneys are damaged. Now in the next video, I'm going to walk you through the one thing you absolutely must be doing if you want to be successful in nursing school. Seriously, friend, do not miss this video. It's one of the most important things I could ever teach you. So make sure that you've clicked the notification bell to get notified when that video goes up. Now make sure to like, comment, subscribe and share this video with a friend. And click on one of these videos here so you can keep rocking nursing school and friend as always. Go become the nurse that God created only you to be. And I will see you in the next video. Take care. Bye bye.
