Lab Testing

Question 1

>20:1 ratio=prerenal pathology (or dehydration) 10:1-20:1=instrinsict kidney damage

Answer 1

BUN:Cr

Question 2

Concentration of nitrogen (as urea) in serum Used in combination with other labs

High: GI bleed, drug effects Low: poor liver/kidney fx

Low: Poor liver/kidney function

Answer 2

BUN

Question 2

Can be suggestive of HTN, diabetic neuropathy, glomerular disease

Answer 2

Protein

Question 4

Indicator of renal (in)sufficiency Better indicator than SCr

Answer 4

Creatine Clearance

Question 5

High result suggests renal failure. Ultimately used as a rough measure of GFR

Answer 5

Serum Creatine

Question 6

Assess handling of Sodium >2% suggests increased sodium excretion and tubular damage

Answer 6

Fractional Excretion of Sodium

Question 7

Measures renal tubular concentration ability. Closely related to specific gravity. Increases with hypovolemia. Decreases with DI, exercise.

Answer 7

Urine Osmolality

Question 8

Used to assess volume status

Answer 8

Urine Sodium