Renal labs Flashcards
Name the renal function tests
BUN
Creatinine
Urinalysis
BUN stands for and measures what
blood urea nitrogen
measures concentration of nitrogen (urea) in serum
Normal BUN
8-20mg/dl
What is the BUN a marker of?
Protein metabolism
- –Kidney failure
- –CHF, acidosis
Creatinine is a catabolic product of _____
creatine (important in skeletal muscle contraction)
Daily production of creatinine depends on ______ _____
muscle mass
Creatinine is entirely excreted by______
Kidneys
Directly related to renal function
T/F: a person with increased muscle mass can have higher creatinine values
True
NL value for creatinine
0.5-1.1 mg /dl
Elevation of creatinine suggests?
Chronicity of renal disease
A doubling of creatinine equals a ______% decrease in renal function.
50%
1.0 - 2.0 is doubling
2 groups that may have lower levels of creatinine
females
debilitated c muscle wasting
NL creatinine clearance? males vs female
90-140 ml/min
Males: 107-140
Females: 90-107
Why is GFR important.
Proper dosing and treatment decisions
What test most accurately assesses GFR?
inulin filtration rate
not available clinically
What is CrCl used for?
assessing kidney fx
Monitor drug therapy
monitor therapetuic drugs and determine doses
CrCl requires 2 things:
24 hr urine
serum drawn w/in 24 hrs of urine collection
Estimated Glomerular filtration rate (EGFR) has what advantages over CrCl?
- no need for 24hr urine collection
- quick, from BMP
What equation estimates crcl without 24hr urine study?
Cockcroft-Gault equation
MDRD stands for?
Modification of diet in renal disease
MDRD equations incorporates what into the equation?
age
Sex
ethnicity
Stage 1 CKD
GFR 90 or higher
NL
Stage 2 CKD
GFR 60-89
Mild loss
Stage 3a CKD
GFR 45-59
mild to mod
Stage 3b CKD
30-44
Mod to severe loss
Stage 4 CKD
GFR 15-29
Severe loss
Stage 5 CKD
GFR<15
Kidney failure