U4 LAB: BUN Flashcards
Nitrogen-containing compounds measured after removal of proteins in specimen
Non-Protein Nitrogen
NPNs are measured by converting nitrogen to?
ammonia
Subsequent reaction with what reagent forms a yellow product?
Nessler’s reagent (K2[HGI4])
Specimen for NPNs
Urine and Plasma
Urea is also known as?
Carbamide
Highest concentration in blood, major excretory product of protein metabolism
Urea
Chemical Formula of Urea
CO(NH2)2
Clinical Applications
- Evaluation of renal function
- Assess hydration status
- Determination of nitrogen balance
- Aid in diagnosis of renal disease
- Verify adequacy of dialysis
More appropriate term for quantification of Urea
Blood Urea Nitrogen (BUN)
Conversion factor
BUN to Urea
2.14
Conversion factor
BUN Conventional to SI
0.357
Most frequently used method
Enzymatic (Urease) Method
This enzyme catalyze hydrolysis of urea and the liberated ammonium ion is quantified.
Urease
Most common assay, best as kinetic measurement
Glutamate dehydrogenase (GLDH)-coupled enzymatic reaction
GLDH
Measures rate of disappearance of reduced ______ at what wavelength?
Nicotinamide adenine dinucloetide, 340 nm