POTASSIUM Flashcards
Assay for potassium is intended for?
Colorimetric method determination of POTASSIUM in human serum and plasma
What cation is the principle cation of the ICF?
Potassium
This is an important constituent of the extracellular fluid due to its influence on muscle activity.
Potassium
What are the intracellular functions of Potassium?
Influencing acid-base balance
Osmotic pressure
Water retention
Hyperkalemia is often associated with what disease?
Renal failure
Dehydration shock or Adrenal insufficiency
Hypokalemia are associated with what diseases?
Malnutrition
Negative nitrogen balance
GIT fluid losses
Hyperactivity of the adrenal cortex
The amount of potassium is determined by using?
Sodium tetraphenylboron
The amount of potassium is determined by using sodium tetraphenylboron to produce a _________________?
Colloidal suspension
What is the relationship of turbidity and potassium concentration in the range of 2-7mEq/L?
Proportional
What is the principle of the test utilizing potassium determination?
Turbidimetry
What are the potassium regents?
Sodium tetraphenylboron 2.1mM
Preservatives and thickening agents
What is the concentration of potassium standard?
Equivalent to 4 mEq/L
Potassium reagent is used for this diagnostic only
In vitro
What is the storage of potassium reagent and standard?
Potassium reagent: 15 - 30C (room temp)
Potassium standard: 2-8C (ref temp)
What is the stability of potassium reagent and standard?
Until expiration date indicated on the package level
Potassium reagent should not be used if?
The reagent is very cloudy
The reagent fails to achieve assigned value on fresh control serum.
Potassium in serum is stable for at least __________ at ______.
2 weeks at 2-8C
TRUE OR FALSE:
Plasma from anticoagulants not containing potassium is not suitable.
False: SUITABLE
What are the interferences of the Potassium test?
Turbid or icteric samples
Bilirubin above 40mg/dL
Nitrogen above 80mg/dL
Hemolyzed sera
What are the materials required but not approved?
Spectrophotometer
Test tubes/rack
Timer
In the laboratory, what is the volume of the potassium reagent added?
1000 uL
In the laboratory activity, what is the volume of the sample, blk and std added?
10uL
How many minutes are the sample, blk and std sit at room temperature?
3 minutes
At what absorbance is the potassium test read?
500nm
The usage of this may not produce accurate results.
Potassium calibrator
What are the other products that may interfere with the procedure and tend to falsely elevate the results?
Preservatives
What should be done if the sample’s value is above 7 mEq/L?
It should be diluted with 1:1 with normal saline, re-assayed and multiplied by 2.
