Introduction to Serum Creatinine Test (Nursing)

00:00 Hi! Welcome to our series on interpreting lab values.

00:04 In this one we're going to give you an introduction to serum creatinine.

00:08 Now if you're going to do a serum creatinine blood test this requires a venous blood sample, you're going to use a gel barrier tube.

00:15 It be a red top tube, a green top tube, that's Heparin or a lavender top tube.

00:22 Creatinine levels are different for men and for women.

00:26 So a normal level for a man is going to be 0.6 to 1.2.

00:31 Women is 0.5 to 1.1.

00:34 Now don't let this throw you off.

00:36 Let's keep in mind that creatinine is attached to muscles. Right? It's part of the muscle metabolism, men tend to have higher percentages of body muscle than women do.

00:47 So just memorize one of those values and keep in mind women are just a notch lower in their normal creatinine levels.

00:55 Alright, so we know what tube you draw it in, we know differences for men and for women just the tiniest bit of difference.

01:03 Now let's look at what serum creatinine is see, it's one of the chemical waste products and it's produced by muscle metabolism.

01:11 That's why the male number is a little bit higher because they generally have higher muscular percentages.

01:17 So it's muscle metabolism to waste product and there's a smaller extent due to eating meat but predominantly creatinine is related to your muscle metabolism.

01:29 Now creatinine is a waste product of creatine the muscles use that to make energy so that all ties together when you think about creatinine I want you to think about muscle metabolism and that males are going to be a little bit higher normal numbers than females.

01:46 Now normally healthy kidneys filter creatinine that waste product and other waste products from your blood into your urine.

01:54 So if I have good strong healthy functioning kidneys, I should have a normal serum creatinine level.

02:02 So that's another key takeaway piece about serum creatinine it assesses renal or kidney function.

02:09 If your kidneys impaired, you're going to have an elevated level of creatinine in your blood.

02:14 So make sure you've got that underline in your notes.

02:17 If I have impaired kidneys watch for elevated serum creatinine.

02:22 Now serum creatinine can also help give an estimate of how well the kidneys are able to filter right down to that specific level.

02:30 GFR is glomerular filtration rate, and a serum c reatinine can help us assess that.