Electrolytes: Phosphate

Question 1

____________
-major__________________
-most phosphorus form is phosphate
-exist as _________ phosphate (part of blood buffer) or ____________phosphate (principal anion within the cells) esters
-____________ related to calcium
-exists in blood in 3 forms:
* Free phosphate - ____
* Complexed phosphate - ____
* Protein bound - ______
-__________________ - inorganic
-most phosphorus ___________________ are organic compounds

Answer 1

Phosphate
intracellular anion
inorganic, organic
inversely
55%
35%
10%
serum phosphate
inside the cell

Question 2

-Hormones:
* ____ - lowers phosphate conc by increasing renal excretion
* ______ - increases by absorption in kidney
* __________ - increases by regulation of skeletal grow

Answer 2

PTH
Vit D
Growth hormone

Question 3

Functions of Phosphate
* Serves as_________
-____________________________________ buffer system
* Serves as _______________________ like ATP

Answer 3

buffer
diphosphate dihydrogen
part of energy molecules

Question 4

Specimen Considerations and Patient Preparation
* ________, _______________-_______, _____________
o Must be ___________
o High _____________ diet - ___________ levels of phosphate
o Separate serum and blood immediately after clotting is completed
o ______________ - anticoagulant of choice
* ________,________, ________ - should not be used
o ________________________ - may also contain phosphate
* No to __________ - False increase
* Diurnal variation
o Highest levels in _______
o Lowest in ________

Answer 4

serum, lithium heparinized plasma, 24 hr urine
fasting
carbohydrate - decreased
dry lithium heparin
oxalate, EDTA, Citrate
commercial heparin preparations
hemolysis
late morning
evening

Question 5

Methodologies
* Formation of __________________________________ (_______-color)
-read at _____ nm
* _________________________ (______________________ method)
-uses molybdate rgt.
-measurement of ammonium molybdate complex at _____ nm (___________ and _______)
-conversion of inorganic phosphate to heteromolybdenum blue by reacting with ammonium molybdate
-reduction to form molybdenum blue, read at _______ nm (Vitros)
-reducing agents:
-ANSA - ______________________
-_________________
-______________
-_____________________________
-serum proteins are precipitated by ____ and ________________ –> converted into phosphomolybdate complex (Mo VI) by the addition of sodium molybdate (________ m)
-pH must be maintained in acid range

Answer 5

• Formation of ammonium phosphomolybdate complex (colorless)
  -340 nm
  *Fiske-Subbarow Method (ammonium molybdate method)
  -at 340 nm (Hitachi dimension and Synchron)
  -conversion of inorganic phosphate to heteromolybdenum blue by reacting with ammonium molybdate
  -660 nm (Vitros)

-ANSA - amino naphthol sulfonic acid
-Stannous chloride
-Ascorbic Acid
-N-phenyl phenylinediamine
-serum proteins are precipitated by TCA and phosphate –> converted into phosphomolybdate complex (Mo VI) by the addition of sodium molybdate (700 nm)
-pH must be maintained in acid range

Question 6

Reference Values
* Serum/Plasma
o Neonate:________________
o Child: __________________
o Adult: ________________

• 24-hour urine - _______________

Conversion Factor
* mg/dL to mmol/L = _________

Answer 6

1.45-2.91 mmol/L
1.45-1.78 mmol/L
0.87-1.45 mmol/L

13-42 mmol/day

0.323