Renal (Kidney) Failure Labs

All right in this lesson we’re going to take a look at Labs that you’ll probably see for your patients who have renal failure.

Like some of the other lessons that you may have seen this lesson and others focus on the different types of labs that you may run into depending on the type of disease, or illness, or injury that a patient may have. This list is not all inclusive, what the purpose is to really focus on giving you guys some sort of idea of the types of labs are groups in Labs that you may see for your patient.

In this lesson we’re really going to focus on the types of labs that you would use for your patient that may have renal failure. Renal failure is a very common admission into the hospital, and the goals and usually are to find out if there’s a problem before the kidneys, and the kidneys or after the kidneys. That’s what we call prerenal, intrarenal, or post renal. The goal here is to develop a plan of care based on the types of results that you’re getting from your Labs on your patient

So like I said this is not an all-encompassing list, but these are the most common types that you’re going to see.

BUN & creatinine focus primarily on kidney function, as well as creatinine clearance. Also you’ll use lab tests like the glomerular filtration rate, and that’s more specific to the kidney. You also take a look at your patient’s comprehensive metabolic panel, including a complete blood count and potentially cultures. The other thing you’ll have to keep in mind our drug levels as some of the medications that your patient may be on could be toxic to the kidneys. Also it’s not uncommon to see biopsies performed or even some Imaging and we’ll go into all of that.

The main focus of checking kidney function is by using the two tests BUN, which is blood urea nitrogen, and creatinine. Both of these are very specific to the kidney, in addition to get a test called creatinine clearance. Important thing that you need to know about the creatinine clearance is that it’s both a serum and a urine test, so you’ll submit both is blood sample and a urine sample. The thing about the urine sample is that it’s a 24-hour urine. If you seen any of the lessons on creatinine, you’ll know that creatinine in the urine is a 24-hour test . So the thing that you need to remember is that you need to place the urine on ice, and also the most important part is you have to discard the first urine sample. Allow the patient avoid then get rid of that sample, and start collecting urine for the next 24 hours after that.

More specific test that indicate kidney function is going to be the glomerular filtration rate, or GFR. There’s a great lesson on GFR, and I encourage you to check that out. But basically the gist of it is that it indicates a percentage of functional kidney. You’re also going to do things like a comprehensive metabolic panel which is going to take a look at other organs like liver function, and protein. Both of those are important to kidney function. The other thing you’ll pay attention to our your electrolytes on your patients metabolic panel.

Another test you’re probably going to see if the complete blood count which were looking for infection or anemia since the kidneys are responsible for the production of epo or erythropoietin.

You’re also going to want to pay attention to any types of cultures that you may run. If there is some concern for some sort of systemic infection, or if there is concern for urinary tract infection, it’s not uncommon or cultures on these samples.

One thing that you going to need to be mindful of is if your patients on any drugs that potentially are toxic to the kidneys and they already have some sort of kidney impairment. They’re not going to be able to filter out those drugs is well or some drugs even may be damaging to the kidneys. You may also need to talk to your provider about adjusting the dose because they don’t have the same kidney function than a normal patient has.

Sometimes you’re patient may have to undergo a kidney biopsy or they may have to undergo some sort of Imaging like a CT scan or a kidney ultrasound, which helps to identify the structure of the kidney and if there’s any problems anatomically with it.

So what do you need to be thinking about whenever you’re getting these labs for your patient?

Well first off your bun, creatinine, and metabolic panel are all going to go in your green top tube.

Any cultures that you do are going to be specific to that type of test. So urine culture is going to go in a urine collection cup and if you’re doing blood culture is you’re going to have to get the blood sample and goes into your blood culture jars.

Drug levels are going to be more specific, and you’re going to need to ask your facility on what the policy is.

For your complete blood count that one goes in a lavender top tube because it’s got the EDTA in it.

If you need to do any Imaging on your patient or the provider needs to get biopsies just asked what the facility policy is so that you can make that process smooth for your patient

The nursing concepts for patient has renal failure look at lab values, because we focus on our patients ability to eliminate and also we pay attention to the fluid and electrolyte balance for them

So let’s recap.

For patients with renal failure we really focus on BUN and creatinine. They are specific to the kidneys and you also need to consider maybe a creatinine clearance for your patient.

The GFR, or the glomerular filtration rate indicates the percentage of the kidney damage that’s occurring.

When you’re looking at your metabolic panels, you’re looking at your overall organ function plus any electrolytes. This is important for your patient because sometimes a liver can be impacted as well as having an electrolyte imbalance.

If there’s some sort of suspicion that there is an infection going on, don’t be surprised if you get cultures on your patient

And finally biopsies and imaging can be really beneficial to your patient especially if they’re in an early stage of kidney failure, so that you can identify the cause of what’s going on and to help plan their care

That’s it for a lesson on Labs that you’ll do for your patients if they have renal failure.Make sure you check out all the resources attached to this lesson. Now, go out and be your best selves today. And, as always, happy nursing!!