U2.3 NPN : Urea [L] Flashcards
Nitrogen-containing compounds measured after removal of proteins in specimen
Non-Protein Nitrogen
Non-Protein Nitrogen is measured by converting _____ to _______
converting nitrogen to ammonia
reagent used to convert nitrogen to ammonia
Nessler’s reagent
product measured spectrophotometrically (color)
yellow product
Measured by converting nitrogen to ammonia and subsequent reaction with Nessler’s reagent (K2[Hgl4]) to form a yellow product measured spectrophotometrically
Non-Protein Nitrogen
Select: Part of Non-Protein Nitrogen (NPN)
A. Urea
B. Creatinine
C. Glucose
D. Uric Acid
A B D
In urine, __________ contributes 4.5% of excreted nitrogen, while __________ contributes 1.7%.
Creatinine, Uric Acid
% of total Urea in Plasma
45-50
% of Urea in urine Concentration
86
Specimens used for Urea Determination
serum, urine & plasma
Also known as carbamide
Urea
Highest concentration in blood
Urea
Urea is produced in the _____ from amino groups (-NH2) and free ammonia
liver
Major excretory product of protein metabolism
Urea
Chemical formula of Urea
CO(NH2)2
T/F Clinical application of urea include evaluation of renal function
T
T/F Clinical application of urea includes assessing hydration status
T
T/F Clinical application of urea include determination of nitrogen balance
T
T/F Clinical application of urea include aid in the diagnosis of liver disease
F renal
T/F Clinical application of urea include verify adequacy of dialysis
T
Select: Clinical applications of Urea testing
A. Evaluation of renal function
B. Determination of blood glucose levels
C. Assessing hydration status
D. Verifying adequacy of dialysis
A C D
More appropriate term for quantification of urea
Blood Urea Nitrogen (BUN) Determination
BUN Determination
Conversion factor (mg/dL to mmol/L):
x 0.357
BUN Determination
BUN to Urea
Urea = BUN x 2.14