Normal Glomerular Filtration Rate (GFR) Test (Nursing)

00:00 Let's talk about a normal GFR because remember actual GFR is really particular to measure its kind of cumbersome.

00:08 So we use an estimate.

00:10 That's a calculation of fancy math using serum creatinine, age, body size, and gender.

00:18 Now, I've heard someone call this a taco and that is a pretty good example.

00:23 I'm from the southwest, we love our tacos.

00:25 So wherever you are, you may too.

00:28 When you're remembering this in your mind, look at this and remember our taco.

00:33 Look at what's right in the middle there.

00:36 Okay. So we've got that yellow piece actually looks like the color of a taco shell.

00:42 120 - 60 if the GFR is 120-60 that's considered normal.

00:47 When you look at your patients lab results, you won't even see a number reported unless it's less than 60.

00:53 So if you get GFR back, there's no number, don't panic.

00:56 Know that it means it's normal. We're right within that range.

00:59 We're not going to see an actual number.

01:02 Now, let's move to the middle chunk between the 60 and 15.

01:07 If it's less than 60, we likely have some kidney disease going on.

01:12 Now you can have kidney disease, you can have damaged your kidney, before your patient even realizes that it's happening.

01:20 Now, look at that last chunk we've got it in red.

01:23 Because the problem there is that's kidney failure.

01:26 If it's less than 15 we have definite kidney failure and huge issues.

01:32 Okay, so it looks like a taco but look at the colors, green, yellow, red, just like a stoplight.

01:40 So if you're in that first range, 60 to 120, normal.

01:44 Everything's fine, green light.

01:46 If you're in the 60 - 15 range, okay, we're on guard because we're thinking this might be an acute issue, this could be a chronic issue.

01:54 We're keeping an eye on it.

01:55 And the closer you tick towards 15, we're in big trouble, that's the red zone, 0 to 15.

02:03 So when you're trying to remember these values for practice and for exams, picture the taco, think, green, yellow, red, and the number should be easier for you to remember.

02:16 Okay, let me give you some values up on the screen for you again.

02:20 Now, here's a lot of words, but you already have laid the groundwork in your brain to remember this.

02:25 So normal estimate GFR for patients is? There you go.

02:31 Look what we're looking for. The actual numbers are noted only when the patient is less than 60.

02:37 So you won't see numbers on your results.

02:41 Okay, so men and women here we go again.

02:43 We're talking about glomerular filtration rate.

02:45 You know, in other lab work we've noted like creatinine that dealt with muscle, it was a little higher in men than women.

02:52 GFR, it's also a little higher for men.

02:55 Look at that a rate of 130.

02:58 Then women is 120.

03:00 I would just use the 120 number that we gave you on our taco and you'll have a great chance of keeping that solid in your brain for memory on tests and in practice.

03:11 Now, as you age GFR changes.

03:14 Look if I was 24 years old, look at our chart, what would your average eGFR be? Right, 116.

03:22 Now, as I move through my 30s, look it drops down a little bit.

03:25 What's the number? Right, 107.

03:29 Hey, hang with me.

03:30 Sometimes when you can answer a question right in nursing school, it's a win, just take it baby.

03:34 It's a win.

03:35 All right. Now, I'm in my 50s.

03:38 Look at my GFR.

03:39 Okay, 93. Compare that in my 20s, which was 116.

03:45 So just want you to keep in mind as you age that GFR through the process of aging is going to decline that's why age needs to be part of the formula.

03:57 So look at this overview.

03:59 We've got GFR as a specific measure of chronic kidney disease.

04:04 Now, before we go anything else, I want you to write in what kind of GFR would you want.

04:09 Just point with your finger. You don't have to write it in.

04:11 Point with your finger what range would you want to be in as far as GFR? Yeah. Hopefully you're pointing in the green range, right? We like to be be in a perfectly healthy strong kidney.

04:21 Now, as it progresses, as kidney disease progresses and as we age, which way would your finger move? Right, you be moving away from 120 closer to 60, closer to the yellow zone.

04:35 Good deal.

04:36 If you can track that with me your understanding the concept and that's spot-on.

04:40 That's what we're looking for.

04:42 So GFR greater than or equal to 60 is considered normal.

04:47 We know that less than 60 means we're heading towards kidney disease.

04:51 And GFR less than 15 is an urgent emergency.

04:56 Now, I'm going to show you the stages of chronic kidney disease.

04:59 Are you with me? Don't memorize this.

05:02 I just want you to see this as a reference.

05:04 So we've got five stages.

05:07 Stage one: Look at that normal GFR or is least greater than 90 Stage 2: Hey, you're still within normal, but you've got mild chronic kidney disease.

05:19 Hey, this is a rough conversation to have with somebody to say, "Hey, I know you don't know there's a problem, but we need to keep an an eye on this." Now, look at the two kidneys.

05:28 See the first one in stage one how it's all pretty much dark-colored? That is stage two.

05:35 That's representing we have fewer functioning nephrons.

05:38 Yeah. There we go.

05:40 Stage 3A: Now it's progressing.

05:42 The numbers are getting lower and we have less of a kidney that's working well.

05:47 Stage 4:Now, we're in severe kidney disease.

05:51 and Stage 5.

05:53 So when you see patients come in and they have a diagnosis of stage 3 chronic kidney disease, this is exactly what they're talking about.

06:00 This is the criteria.

06:01 Do I want you to memorize this? No, you don't have enough real estate in your brain to memorize this.

06:08 You do have enough real estate to remember taco, red, yellow, green, 120, 60, 15.

06:15 That anybody can do.

06:17 This is information you can look up when you need it.

06:21 Just keep in mind stage one, super. Stage 5, yikes.

06:25 We're on some type of dialysis in Stage 5.