Electrolytes Ctnd Flashcards
Major extracellular anion
CHLORIDE
CHLORIDE
FUNCTIONS
• Involved in maintaining osmolality, blood volume, and electric neutrality
• Chloride shifts secondarily to a movement of sodium or bicarbonate ions
Chloride Specimen Consideration
• Specimens:
Serum
plasma(Li heparin)
whole blood
urine (24-hour)
sweat
Used to measure cystic fibrosis
Sweat (sweat patch
CHLORIDE
Hemolysis…
• However, with marked hemolysis, levels may be______ as a result of a dilutional effect
does not cause a significant change in serum or plasma values
decreased
Chloride Determination
ISE
AMPEROMETRIC COULORIMETRIC METHOD
MERCURIMETRIC TITRATION
MERCURIC THIOCYANATE
Chloride
reference method
ISE
Chloride ISE
• lon exchange membrane
- Tri-n-octylpropylammonium chloride decanol
TRI-N-OPA CD
Chloride
• Amperometric-coulometric titration
Measuring device
• Cotlove Chloridometer
Chloride
Ag + 2Cl → AgCl
Excess or free Ag → endpoint of titration
What method?
Amperometric coulorimetric titration method
(Schales and Schales Method)
Mercurimetric Titration
Chloride
Mercurimetric Titration
• Precipitating agent:
tungstic acid
Chloride
Mercurimetric titration method
________is titrated with a standard solution of mercuric ions (_____) to form a soluble compound of_____, which does not dissociate to mercuric ions
Excess mercuric ions combine with_________(indicator) to form a______ complex
Protein Free Filter
mercuric nitrate
mercuric chloride
s- diphenylcarbazone
blue-violet colored complex
Chloride
• Specimen is mixed with a solution of mercuric thiocyanate
Mercuric chloride - final product
Mercuric Thiocyanate (Whitehorn Titration) Method
Chloride
• Free thiocyanate reacts with ferric ions present in ferric nitrate to form a reddish-brown complex
Mercuric Thiocyanate (Whitehorn Titration) Method
Method 1.2
Chloride ions react with a mercury(II)-2,4,6-tri-(2-pyridyl)-s-triazine
(TPTZ) complex to form mercury(Il)-chioride. The liberated TPTZ reacts with iron(il) ions yielding ablue coloured complex
The resulting absorbance change at____ is directly proportional to the amount of chloride ions in the sample.
590 mm
Chloride package insert
Mix, incubate for____ minutes in the darkand measure the absor-bance of sample (Asample) and STD (Ast)) within____ minutes against the reagent blank. Do not expose to light!
5
60
• Composes the largest fraction of the total carbon dioxide
Bicarbonate (>90%)
Bicarbonate
• Specimen
• Venous serum or heparinized plasma
• Anaerobic collection
If the sample is left uncapped before analysis, CO2 escapes (decrease by….)
Bicarbonate
6 mmol/L per hour)
Bicarbonate Determination
• Uses an acid to convert all the forms of CO, to CO, gas and is measured by a pCO, electrode
ISE
• Alkalinizes the sample to convert all forms of CO, to CO3-
Enzymatic Method
Bicarbonate Reference Range
Reference Ranges
CO2-venous 23 to 29 mmol/L (plasma, serum
• Fifth most common element
• Most prevalent cation in the human body
Calcium
Calcium FUNCTIONS
• skeletal mineralization
• blood coagulation
• neural transmission
• plasma buffering capacity and enzyme activity
• maintenance of normal muscle tone and excitability of skeletal and cardiac muscle
Calcium Distribution
• → bone
• → circulation (blood) + ECF
99%
1%
Calcium Distribution
• 1% → circulation (blood) + ECF
• → bound to anions (citrate, bicarbonate, lactate)
• → bound to protein (albumin)
• → free/ ionized Ca?+
15%
40%
45%
Calcium Specimen Consideration
For total calcium determination:
• Serum
• Lithium heparin plasma collected without venous stasis
• Do not use EDTA, oxalate, or citrate
Calcium Specimen Consideration
For ionized calcium determination:
Samples must be collected anaerobically, transported on ice, and stored at 4 degrees Celsius to prevent loss of COz
Heparinized plasma (Do not use heparin in liquid form)
Calcium Specimen Consideration
For urine calcium determination:
24-hour urine sample acidified with 6mol/L HCl
1mL of acid added for each 100mL urine
Calcium Determination
• Ortho-cresolphthalein Complexone Method
• Arsenazo Ill Dye Method
• AAS (Reference method)
• ISE (Current Method)
Calcium Determination
• Ortho-cresolphthalein Complexone(CPC) Method
• O-CPC reacts with calcium to form _____ in alkaline solution, which is measured at near____
• Uses______ to prevent magnesium interference
red color; 580 nm
8-hydroxyquinoline
Calcium Determination
• Arsenazo Ill reacts with calcium to form a calcium-indicator complex
usually measured at near___
• Arsenazo III Dye Method
650 nm
Calcium Determination
• Certain dye solutions like cal-red, calcein, ammonium purate, and Eriochrome Black T have a characteristic color in the presence of ionized calcium.
The addition of a chelating agent binds the calcium, and a change in color results.
EDTA Titration (Bachra, Dower, and Sobel)
EDTA Titration
(Bachra, Dower, and Sobel)
Calcium Determination
• calcium is first precipitated as calcium oxalate, converted to oxalic acid with sulfuric acid, and then measured by titration against potassium permanganate
Clark-Collip Precipitation method
Calcium Determination
• Clark-Collip Precipitation method
• calcium is first precipitated as calcium oxalate, converted to oxalic acid with sulfuric acid, and then measured by titration against…
potassium permanganate
Calcium Determination
Calcium is precipitated as calcium chloranilate by sodium chloranilate solution
Excess chloranilic acid is removed by washing the precipitate with isopropyl alcohol
Precipitate is treated with EDTA, which chelates calcium and releases chloranilic acid (purple color)
• Ferro Ham Chloranilic Acid Precipitation
Calcium Determination
• Ferro Ham Chloranilic Acid Precipitation
Calcium is precipitated as calcium chloranilate by _____solution
Excess chloranilic acid is removed by washing the precipitate with isopropyl alcohol
Precipitate is treated with EDTA, which chelates calcium and releases_____
sodium chloranilate
chloranilic acid (purple color)
Found everywhere in living cells (major intracellular anion)
Phosphate
• Reservoirs of biochemical energy
ATP, creatine phosphate, and PEP
2,3-BPG in red blood cells
Phosphate
• Participate in many of the most important biochemical processes
• Inversely related to calcium
Phosphate
Phosphate
_____%present in the skeletons
• Primarily inorganic phosphate, predominantly as hydroxyapatite and calcium phosphate
80 - 85%
Phosphate
•____% present in the ECF in the form of inorganic phosphates
• intracellularly in the soft tissues in the form of organic phosphates
15%
Phosphate Specimen Consideration
• Specimen
• Serum
• Lithium heparin plasma
• 24-hour urine
• Circulating phosphate levels are subject to_____ rhythm
•____ in the late morning and_____ in the evening
circadian rhythm
Highest; lowest
Phosphate Determination
• Involve the formation of an ammonium phosphomolybdate complex
• Measured by UV at 340 nm or can be reduced to molybdenum blue, which is read between 600 and 700 nm
• Fiske-Subbarow Method
Phosphate Determination
• Fiske-Subbarow Method
• Involve the formation of an_______
• Measured by UV at____ or can be reduced to______, which is read between_______
ammonium phosphomolybdate complex
340 nm
molybdenum blue
600 and 700 nm
Fiske Subarrow (Phosphate)
• Reducing agents: PEAS
pictol (ammonium napthol sulfonic acid),
elon (methyl amino phenol)
ascorbic acid
senidine (N-phenyl-P-phenylene Diamine
Hydrochloride),
• Is a by-product of an emergency mechanism that produces a small amount of ATP when oxygen delivery is severely diminished
Lactate
_____is the normal end product of glucose metabolism (glycolysis)
• Conversion to_____ is activated when a deficiency of oxygen leads to an accumulation of excess NADH
Pyruvate
lactate
Lactate Specimen Consideration
• Tourniquet should not be used
• After sample collection, anaerobic glycolysis will occur
LACTATE
Specimens:
plasma or whole blood
Lactate
• After sample collection, anaerobic glycolysis will occur
• Heparinized plasma but must be______, and the plasma must be separated quickly
delivered on ice
Lactate
inhibit glycolysis but the specific method directions must be consulted
Fluoride and iodoacetate
Lactate Determination
• Uses lactate oxidase to produce pyruvate and hydrogen peroxide
Addition of chromogen and catalyzed by peroxidase to form a colored complex
• Enzymatic Method
Lactate Determination
• Enzymatic Method
• Uses_____ to produce _____ and _____
• Addition of_____ and catalyzed by______ to form a colored complex
lactate oxidase
pyruvate and hydrogen peroxide
chromogen
peroxidase
• Useful in indicating an increase in one or more of the unmeasured anions in the serum
• As a form of quality control for the analyzer used to measure electrolytes
Anion Gap
Anion gap
It has a reference range of
10 to 20 mmol/L.
Anion Gap
• Concentration difference between…
commonly measured cations (Na + K) and commonly measured anions (Cl + HCO3)
Bawal ang venous stasis sa kay?
Total calcium
Ionized calcium must be transported
With ice
Collected anaerobically
Stored at 4C
Prevents loss of CO2
Asa tung bawal ang liquid form sa heparin?
Ionized calcium
For urine calcium determination… urine must be…
Acidified with 6mol/L HCl
1ml of HCl per 100mL of urine