Transcript Clinical Chemistry

Clinical Chemistry
Clinical Pathology, K. Canga, RVT
Reading and Assignment
Laboratory Procedures for Veterinary
Technicians,pp: 75 – 113
 Study Guide as desired

Sample Collection & Handling
Most chemical analyses require collection and
preparation of _____________ samples
 Whole blood or blood plasma may be used for some
test methods or with specific types of equipment
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◦ Do not use __________; ___________ is usually the best
choice for clinical chemistry samples
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Most adverse affects on sample quality can be avoided
by careful sample ___________________ and
________________.
Sample Collection & Handling
Specific blood collection protocols vary depending
on patient ______________, volume of blood
needed, method of restraint, and type of sample
needed
 Collect blood samples for chemical testing
______________ beginning treatment.
 __________________________ samples are
preferred; postprandial samples may produce
inaccurate results.
 Label sample tube with _________ and time of
collection, ______________ (owner’s and
patient’s), and patient’s ______number.
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Serum Sample Collection
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Blood should be collected from __________, fasted animal
when possible
Avoid ________________ by selecting needles of the
correct size.
Place blood in a tube that contains no
_____________________. (Serum Separator tubes can
also be used.)
Allow blood to clot at room temperature for 20 to 30
minutes. (If SST used, gently invert before clotting)
Gently separate clot by “_____________” with a wooden
stick around the inside of the tube.
Replace top and centrifuge at 2000 to 3000 rpm for 10
minutes.
Remove ___________ with a pipette and transfer to
appropriate container.
Factors Influencing Results
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_______________: may result when a blood sample is:
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drawn into a moist syringe
drawn in through too __________ of a needle
drawn too _____________ in to needle
mixed too __________________ after collection
forced through a ___________ when being transferred to a
tube
◦ _________________ as a whole blood sample
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Hemolysis can also occur when excess ____________
is used to clean the skin and not allowed to dry prior to
drawing blood.
Hemolysis
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Fluid from ________________ blood cells can
dilute the sample, resulting in falsely ___________
concentrations of constituents present in the animal.
Certain constituents, normally not found in high
concentrations in serum or plasma, escape from
ruptured blood cells, causing falsely elevated
concentrations in the sample.
Hemolysis may elevate levels of _____________,
organic phosphorus, and certain ______________
in the blood
Hemolysis also interferes with __________ activity
and ________________ determinations.
Factors Influencing Results
_________________ contamination: collection
tubes must be chemically pure
 Improper ______________: label all tubes properly.
 _________________ influences: obtain samples
from a _____________animal
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◦ Postprandial samples may have increased blood
______________ levels and decreased inorganic
phosphorus.
◦ _______________ results in turbid or cloudy serum
◦ _________________ assays affected due to increase
in GFR after eating.
Factors Influencing Results
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Improper Sample Handling: complete chemical
analysis within __________ of sample
collection.
◦ Do not allow samples to become too _________.
◦ Thoroughly mix serum or plasma that has been
frozen after thawing to avoid
____________________ gradients.
Reference Ranges
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Reference ranges are a range of values
derived when a __________________ has
repeatedly assayed samples from a significant
number of clinically _____________ animals
of a given species using specific test methods.
Protein Assays
Plasma proteins are produced primarily by the
___________ , as well as
__________________________ tissues,
_______________ tissues, and ___________ cells
 Plasma proteins have many functions:
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◦ Form the structural matrix of all ________, ___________,
and ______________
◦ Maintain _________________ pressure
◦ Serve as enzymes for biochemical reactions
◦ Act as ________________ in acid-base balance
◦ Serve as _______________
◦ Function in blood ___________________
◦ Defend the body against pathogenic microorganisms
◦ Serve as _____________/______________molecules for
most constituents of plasma
Protein Assays
Total Plasma Protein
 Total Serum Protein
 Albumin
 Globulins
 Albumin/Globulin Ratio
 Fibrinogen
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Protein Assays
Total _____________ protein measurements include
fibrinogen values
 Total _____________ protein determinations
measure all the protein fractions except fibrinogen.
 Total protein concentration may be affected by altered
_____________ synthesis, altered protein
_________________, and altered protein
______________ or excretion, as well as
_________________ or ____________________.
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Determination of Total Protein Levels:
Refractometric & Biuret Photometric Methods
Refractometric method measures the refractive
index of serum or plasma with a
_____________________________.
 Refractive index of the sample is a function of the
concentration of solid particles in the sample. In
plasma, the primary solids are the _______________.
 Biuret method measures the number of molecules
containing more than three peptide bonds in serum or
plasma. (Done via ______________)
 Note: Both techniques are _______________
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Albumin
Albumin comprises 35% to 50% of the total plasma
_______________ in most animals.
 Significant _____________________________ is
most likely caused by albumin loss.
 ___________ disease, ___________ disease, dietary
intake, and intestinal protein _______________ may
influence the plasma albumin level.
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Globulins: Complex Group of ______________
____________ globulins are synthesized in the
___________ and primarily transport and bind
proteins.
 __________ globulins include complement (C3 & C4),
transferrin, and ferritin
 _______________ globulins (immunobulins) are
synthesized by ___________ cells
 Concentration is calculated by determining difference
between total protein and albumin concentrations.
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Albumin/globulin (A/G) ratio
Alteration in the normal ratio is frequently
the first indication of a protein abnormality
 Determined by dividing the albumin
concentration by the globulin concentration.
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Fibrinogen
3% to 6% of the total plasma protein content
 Most common method of fibrinogen
evaluation is the heat precipitation test (If
you would like to know more about this,
please reference chapter 2, pg 71).
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Hepatobiliary Assays
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Liver functions include:
◦ _________________ of amino acids,
carbohydrates, and lipids
◦ _______________ of albumin, cholesterol, plasma
protein, and clotting factors
◦ ___________________ and
________________ of nutrients related to bile
formation
◦ secretion of ______________, or bile
◦ _________________, such as detoxification of
toxins and ________________of certain drugs
Hepatobiliary Assays
The __________________ is closely associated
with the liver, both anatomically and functionally; its
primary function is as a storage site for _________.
 More than 100 different types of tests can be used to
evaluate liver function
 Liver disease is usually greatly ________________
before clinical signs appear.
 Damage to one _________ of the liver may not
affect all liver functions.
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Hepatobiliary Assays
Liver function tests are designed to measure
substances ________________ by the liver, modified
by the liver, _________________ when
_________________ are damaged, or those
enzymes with altered serum concentrations as a result
of _________________.
 Liver function tests are usually done with serial
determinations and several different types of liver tests
completed to assist in verifying functional status.
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Enzymes Released from Damaged
Hepatocytes
Alanine aminotransferase (ALT)
Aspartate aminotransferase (AST)
Sorbitol dehydrogenase
Glutamate dehydrogenase
Alanine Aminotransferase (ALT)
Enzyme found free in the cytoplasm of hepatocytes
Considered a ________-specific enzyme in dogs,
cats, and primates
 ___________, ruminants, ________, and
___________ do not have enough ALT in the
hepatocytes for this enzyme to be considered liver
specific
 Other sources of ALT are _________ cells,
_____________ muscle, ____________ muscle,
and the _______________.
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ALT (cont’d)
Used as a __________________ test for liver
disease because it is not precise enough to identify
specific liver diseases
 Increases are usually seen within _____ hours of
hepatocyte damage and peak levels in 24 to 48
hours
 Serum levels will return to reference ranges within
a few weeks unless _____________ liver damage
is present.
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Aspartate Aminotransferase (AST)
Found free in the cytoplasm of hepatocytes and
bound to the __________________ membrane.
 Levels tend to rise more ___________ than ALT
and return to normal levels within a day if chronic
liver insult is not present
 Found in __________________ amounts in many
other tissues, including _______, cardiac muscle,
____________ muscle, ______________, and
pancreas
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AST (cont’d)
Increased blood level may indicate
_______________ liver damage or be
caused by strenuous exercise or
intramuscular injection
 Assess _________ ____________ activity
to rule out muscle damage before
attributing an AST increase to liver damage.
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Sorbitol Dehydrogenase
Found in liver, kidney, small intestine, skeletal muscle,
and RBCs
 Especially useful for evaluating liver damage in
___________ animals such as ________, ________,
_________, ___________, and ____________.
 Plasma level rises __________ with
___________________ damage or ____________.
 Assays can be used in all species to detect
hepatocellular damage or necrosis
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◦ Tests not readily available to average vet. lab.
Glutamate dehydrogenase
Mitochondrial-bound enzyme found in high
concentrations in the hepatocytes of cattle,
sheep, and goats
 No standardized test method has been
developed for use in a veterinary practice
laboratory
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Enzymes Associated with
Cholestasis
Alkaline phosphatase (AP)
Gamma glutamyltransferase (GGT)
Alkaline Phosphatase (AP)
Present as isoenzymes in _________________ in
bone, and as ___________________ in cartilage,
intestine, placenta, and cells of the hepatobilary system
in the liver.
 Isoenzymes of AP remain in circulation for
approximately 2 to 3 days, with the exception of
intestinal isoenzyme, which circulates for just a few
hours.
 A corticosteroid isoenzyme of AP has been identified
in dogs with exposure to increased endogenous or
exogenous ______________________________.
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AP (cont’d)
Source of an isoenzyme or location of the
damaged tissue is determined by
electrophoresis and other tests performed in
commercial or research laboratories.
 In older animals, nearly all circulating AP
comes from the ___________ as
_________ development stabilizes.
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AP (cont’d)
Assay in a practice laboratory determines the
total blood concentration.
 Concentrations used to detect
_________________ in adult dogs and cats
 Not a useful test for detecting cholestasis in
cattle and sheep because of wide fluctuations
in ____________blood levels in these
species.
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Gamma glutamyltransferase (GGT)
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Also called gamma glutamyltranspeptidase
Primary source is ____________
Also found in _________ , _____________, and
_____________,epithelia, as well as in the kidneys,
pancreas, intestine, and muscle cells
Cattle, horses, sheep, goats, and birds have
___________blood activity than dogs and cats
Blood level is evaluated with liver disease, especially
_________________disease.
Hepatocyte Function Tests
Bilirubin
Bile acids
Cholesterol
Others (dye excretion, ammonia tolerance,
caffeine clearance)
Hepatocyte Function Tests
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Evaluated substances are taken up, modified,
produced, and/or secreted by the liver,
primarily _____________ and
__________ acids; other tests include
albumin, ammonia, and cholesterol.
Bilirubin
Derived from the breakdown of
___________________ by macrophages in the
_____________
 Measurements of the circulating levels of these
various populations of bilirubin can help pinpoint the
cause of _______________.
 Assays can directly measure _________ bilirubin
(____________ bilirubin plus ________________
bilirubin), and _______________ bilirubin
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Bilirubin (cont’d)
Blood levels of _______________ bilirubin are
elevated with _________________ damage or bile
duct injury/obstruction
 Blood levels of ___________________ bilirubin
are elevated with excessive erythrocyte
__________________ or defects in the transport
mechanism that allow bilirubin to enter hepatocytes
for conjugation.
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Bile Acids
Aid in ______ absorption and modulate
cholesterol levels
 Synthesized by hepatocytes from cholesterol and
conjugated with glycine or taurine
 Conjugated bile acids are secreted across the
_______________ membrane and reach the
duodenum by the biliary system
 Gallbladder stores ________ acids (except in the
___________) until contraction associated with
feeding.
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Bile Acids (cont’d)
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Any process that impairs the hepatocellular, biliary, or
portal enterohepatic circulation of bile acids results in
elevated serum levels.
Serum level is normally ______________ after a meal
because the gallbladder has contracted and released
increased amounts of _______ into the
__________________.
Paired serum samples performed after 12 hours of fasting
and 2 hours postprandial are needed to perform the test.
◦ Difference in concentration of the samples is reported
◦ Only a single sample is tested in horses.
Bile Acids (cont’d)
Inadequate ______________ or spontaneous
___________________ contraction can increase
fasting bile acids; prolonged fasting and
_______________ decreases bile acids
 Most commonly used method for determination of
bile acids is an enzymatic method measured by
machine
 Bile acid test that uses immunologic methods
(ELISA) is available for use in the veterinary clinic.
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Cholesterol
Produced primarily in the __________ and
ingested in food.
 _________________ causes an increase in
serum cholesterol in some species
 Some automated analyzers provide
cholesterol and other lipoprotein values
 Fluoride and oxalate anticoagulants may
______________ enzymatic method results
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Cholesterol (cont’d)
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Assay is sometimes used as a screening test for
________________________
◦ _______________ hormone controls
_________________ and _____________________ of
cholesterol in the body
Other diseases associated with hypercholesterolemia
include _____________________________,
_______________ ____________, and nephrotic
syndrome.
 Administration of ____________________ may
also cause an elevated blood cholesterol
concentration.
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Other Tests of Liver Function
Dye excretion: bromsulfophthalein excretion and
indocyanine green excretion tests require
administration of a dye that binds to a protein in
serum.
 Ammonia tolerance: any condition that reduces the
uptake of ammonia or conversion of ammonia to
urea can lead to increased plasma ammonia
concentration.
 Caffeine clearance: test used in human medicine;
few experimental studies have been performed in
canine species.
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Kidney Assays
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Kidney functions:
◦ _______________ or ____________water and
electrolytes in times of imbalance.
◦ Excrete or conserve _________ ions to maintain blood
_______ within normal limits.
◦ Conserve ________________
◦ Remove end products of ______________ metabolism
◦ Produce renin, _______, and prostaglandins
◦ Lower blood pressure
◦ Regulate acid secretion in the stomach
◦ Aid in regulation of body temperature and platelet
aggregation
◦ Aid in vitamin D activation
Kidney Assays
Kidneys receive blood from the _________ arteries;
blood enters the ________________ of the
______________where nearly all water and small
dissolved solutes pass into the collecting tubules.
 Each nephron contains sections that function to
______________ or ____________specific solutes.
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◦ Resorption of glucose occurs in the _______
◦ Secretion and reabsorption of mineral salts occurs in the
ascending limb of the loop of __________ and in the
__________.
Kidney Assays (cont’d)
Nephron has a specific reabsorptive
capability for each substance called the
_________________________.
 Blood returns from the _____________ to
the rest of the body through the renal
__________, which connect to the caudal
___________ ___________.
 _____________ and ___________ may be
analyzed to evaluate kidney function.
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Kidney Assays (cont’d)
Primary serum chemistry tests for kidney
function: ____________________ and
______________.
 Other tests are designed to evaluate the
rate and efficiency of
__________________ filtration.
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Blood Urea Nitrogen (BUN)
Also called serum urea nitrogen
 Urea is the principal end product of __________________
breakdown in mammals.
 Urea passes through the glomerulus and enters the renal
tubules
 Approximately __________ the urea is reabsorbed in the
tubules and the remainder excreted in the urine
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◦ If the kidneys do not remove sufficient urea from the plasma,
BUN levels _________________.
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Contamination of the blood sample with urease-producing
bacteria may result in decomposition of urea and decreased
BUN levels.
◦ Staphylococcus aureus, Proteus spp. and Klebsiella spp.
BUN (cont’d)
Several photometric tests are available to measure
urea nitrogen
 _________________ results in increased retention
of urea in the blood (_______________)
 High-______________ diets and strenuous
exercise may cause elevated BUN levels because of
increased _____________________ breakdown.
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Serum Creatinine
Formed from creatine found in ____________
muscle as part of muscle metabolism
 Creatine diffuses out of muscle cells and into most
body fluids, including ___________
 Amount of creatine metabolized to creatinine
usually remains _______________, as does blood
level of creatinine
 Total amount of ______________ is a function of
the animal’s total muscle mass.
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Creatinine (cont’d)
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Serum creatinine is filtered through the
_______________ and eliminated in urine
◦ Any condition that ___________ glomerular
filtration rate alters serum ____________ level
Nearly ____% of kidney tissue must be
_________________ before blood creatinine
levels rise.
 __________________ decreases in creatinine
occur from transient increase in glomerular
filtration rate after a meal.
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Creatinine (cont’d)
Increased serum creatinine levels are seen when
there is a lack of functional _______________
 Serum creatinine concentrations are influenced by:
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◦ Fluid and _______________ levels
◦ _____________ factors, such as shock
◦ _________________ factors, such as bladder and
urethral obstructions
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Used to evaluate __________________ function
BUN/Creatinine Ratio
Both measurements have a wide range of
reference intervals
 Used in human medicine for diagnosis of renal
disease
 BUN and creatinine have an ___________
logarithmic relation.
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Urine Protein/Creatinine Ratio
Mathematical method that compares urine
______________ level with urine
_____________________ levels in a single urine
sample
 5 to 10 mL of urine collected via
________________________.
 Sample is centrifuged and
____________________ used to determine both
concentrations for each sample by photometric
methods.
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Pancreas Assays
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The pancreas has both ______________ and
_________________ functions.
◦ Pancreatic endocrine function involves production of
____________ and ___________. Diabetes mellitus,
or a deficiency of ___________ resulting in
hyperglycemia, is the most common endocrine disorder
of the pancreas.
◦ Pancreatic exocrine function involves the production
of ____________, _____________, and
____________. Most pancreatic disturbances occur in
the exocrine function of the pancreas. ___________
seem to have a greater incidence than ____________.
Pancreas Assays
Exocrine pancreas: also referred to as the acinar
pancreas.
 Secretes enzymes necessary for ____________
into the small intestine
 Primary pancreatic enzymes are trypsin, amylase, and
lipase
 Trauma to pancreatic tissue is often associated with
pancreatic duct ____________________ that
results in a back-up of digestive enzymes into
peripheral circulation.
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Pancreas Assays
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Endocrine Pancreas: interspersed within the
exocrine pancreatic tissue are the __________ of
_________________
Four types of islet cells present; designated as
α(_________), β(__________), δ(________), and
____ cells.
Delta and PP cells comprise less than 1% of the islet
cells and secrete somatostatin and pancreatic
polypeptide, respectively.
Beta cells comprise approximately _____% of the
islet cells and secrete _____________.
20% consists of alpha cells that secrete glucagon and
somatostatin.
Pancreas Assays
Diseases of the pancreas may result in
inflammation and cellular damage that causes
leakage of ______________ enzymes or
insufficient ___________________ or
___________________of enzymes.
 Primary ______________ pancreas tests
are amylase and lipase; trypsinlike
immunoreactivity and pancreatic lipase
immunoreactivity
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Amylase
Primary source is the pancreas, but also produced in
the ______________ glands and small intestine.
 Increases in serum amylase are nearly always caused
by pancreatic disease (_________________),
especially when accompanied by increased lipase
levels
 ______________, intestinal obstruction, or
intestinal ___________________may also result in
increased serum amylase from increased absorption
of intestinal amylase into bloodstream.
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Amylase (cont’d)
Animals have a greater serum amylase activity level
than humans (___ times greater in dog and cat) so it
is recommended to dilute the serum with normal
saline before testing if using tests designed for human
samples.
 ______________, ________________, and calcium
cheleating anticoagulants will affect results.
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Lipase
Nearly all serum lipase is derived from the
____________________.
 Excess lipase is normally filtered through the
________________, so lipase levels tend to remain
normal in the early stages of pancreatic disease.
 Increased lipase is also seen in ___________ failure,
hyperadrenocorticism, dexamethasone treatment,
and bile tract disease.
 Manual methods for testing are cumbersome, easier
to use automated or SNAP test.
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Trypsinlike Immunoreactivity (TLI)
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Considered the test of choice, TLI is highly specific and
sensitive in detecting __________________ insufficiency in
dogs.
Radioimmunoassay using antibodies to trypsin that can detect
both trypsinogen and trypsin
Antibodies are species specific
Trypsin and trypsinogen are produced only in the pancreas
Serum TLI decreases in parallel with functional pancreatic
mass
Decreased _____________filtration rate increases TLI
Important to fast animal for ___ hours prior to collecting
sample.
Serum Pancreatic Lipase
Immunoreactivity (PLI)
Serum feline PLI is specific for
___________________ and is
recommended instead of the previously
validated serum feline TLI to diagnose cats
with symptoms of pancreatitis.
 Cats must also be fasted for ___ hours
prior to drawing blood sample.
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Pancreas Assays
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Endocrine Pancreas Tests
Primary test is blood __________; others
include fructosamine, beta-hydroxybutyrate,
glycosylated hemoglobin, serum cholesterol,
and triglyceride
Glucose
Pancreatic islets respond directly to blood glucose
concentrations and release ____________ (from
the beta cells) or ______________ (from the
alpha cells) as needed.
 Blood glucose level is used as an indicator of
_____________________ metabolism in the
body and as a measure of _________________
function of the ________________.
 Some tests for blood glucose react with only
glucose, whereas others may quantify all sugars in
the blood.
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Glucose (cont’d)
Ideally, samples should be taken from an animal
that has been fasted for ___ to ___ hours
(ruminants should not be fasted)
 ____________ is preferred
 It is essential to centrifuge sample and transfer
serum to another tube immediately because
blood continues to use glucose at a rate of 7%
to 10% per hour if allowed to remain in contact
with the serum or plasma.
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Glucose (cont’d)
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_______________________ may result from
______________ ____________, or any of
several nonpancreatic causes such as stress and
hyperadrenocorticism (_____________ disease)
*Diagnosis of diabetes mellitus is not made unless
_________________ accompanies hyperglycemia.
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_______________________ may result from
malabsorption, severe liver disease, or prolonged
contact of the _________ or _________ with the
cellular component of blood.
Fructosamine
Represents irreversible reaction of glucose
bound to protein, particularly
_____________.
 Increased fructosamine indicates persistent
____________________.
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Glucose Tolerance Test
Sometimes referred to as “glucose curve”
 Challenge the pancreas with a glucose load
and measure ___________ effect by blood
or urine glucose concentrations; used to
rule out __________ ____________.
 IV test is preferred over oral because oral
test is affected by abnormal intestinal
function such as ______________ or
hypermotility, and excitement.

Glucose Tolerance Test (cont’d)
Glucose is injected after a 12- to 16-hour
fast (except in ruminants)
 Blood glucose is subsequently checked and
progress mapped as a tolerance curve.
 Results are standardized as disappearance
half-lives or glucose turnover rates
expressed as percent/minute
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Insulin Tolerance Test
Probes causes of diabetes mellitus
 Serum glucose levels are measured in
blood samples obtained before
__________ injection (fasting blood
glucose) and every ___ minutes after
injection for __ hours.
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Other Endocrine Pancreas Tests
Glucagon tolerance: indicated when repeated
borderline results are obtained.
 Insulin/glucose ratio: involves simultaneous
measurements in a fasting animal.
 Miscellaneous tests of insulin release: glucose,
epinephrine, leucine, tolbutamide, or calcium
challenges may be attempted.
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Other Endocrine System Assays
Adrenocortical Function Tests
Thyroid Assays
Pituitary Function Tests
Adrenocortical Function Tests
Brain or pituitary ___________ leading to
secondary bilateral adrenal ____________,
idiopathic adrenal hyperplasia, or neoplasia may cause
excessive ____________ release and
_________________________. (Cushing’s
disease)
 Misuse of _________________________ is the
most common cause of cortisol excess.
 ___________________________, (Addison’s
disease) includes mineralocorticoid deficiency, which
does not occur in iatrogenic disease from rapid
withdrawal of _________________________.
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Adrenocortical Function Tests (cont’d)
Addison’s disease also may result from Lysodren (Rx
for adrenal hyperplasia) or from
____________________ causes.
 Dogs with nonadrenal disease such as diabetes
mellitus, liver disease, or renal disease may have falsepositive results
 _________________________ hormone (ACTH)
and _____________ concentrations may be a
helpful diagnostic aid in differentiating primary
(adrenal-dependent) from secondary (pituitarydependent) hypoadrenocorticism.
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Adrenocortical Function Tests (cont’d)
Measurements taken as _____________ data and
compared with data obtained from challenge to the
adrenal gland with ACTH or dexamethasone.
 Low to undetectable ACTH concentrations occur in
secondary Addison’s disease, whereas normal (or
increased) concentrations are expected in primary
Addison’s disease.
 Refer to pp 100-101 in your textbook for step-bystep instructions on performing ACTH stim. and
Dex. suppression tests!
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Thyroid Assays
Baseline thyroxine (T4) concentrations are used
diagnostically, but normal values vary dramatically
 Semiquantitative immunologic tests are available to
measure T4 concentrations
 ________ response test is used on small animals
(except _________________ cats) and horses
and provides a reliable diagnostic separation of
patients with normal versus abnormal thyroid
function.

Thyroid Assays (cont’d)
Free T4 test measures the fraction of thyroxine
not bound to protein; levels are less influenced by
nonthyroidal diseases or drugs than are total T4
concentrations.
 Triiodothyronine (T3) suppression test: based on
the expected ____________________
regulation of TSH; induced by high concentrations
of circulating thyroid hormone.
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Pituitary Function Tests
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Diagnosis of canine ______________ may
be based on documentation of elevated
____________ hormone (GH).
Electrolyte Assays
Electrolytes: negative ions, or ___________, and
positive ions, or ___________, of elements found in
all body fluids of all organisms.
 Functions of electrolytes include:
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◦
◦
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maintenance of ________ balance,
fluid ____________ pressure, and
normal ___________ and ____________ functions.
Also function in the maintenance and activation of several
enzyme systems and in acid-base regulation
Acid-base status depends on _________________
and should be interpreted together.
Electrolyte Assays
___________, ______________,
____________, and ________________
are the four electrolytes in plasma.
 Minerals of importance are __________,
_____________, and ______________.
 These two groups together are often
simply called “________________”
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Electrolyte Assays
Calcium
Inorganic Phosphorus
Sodium
Potassium
Magnesium
Chloride
Bicarbonate
Calcium
Do not use _______, _________, or _________
anticoagulants to collect calcium samples for testing
because they bind with calcium and make it
unavailable for assay.
 ___% of the body’s calcium is in _________.
 Remaining calcium maintains
__________________ excitability and tone, acts as
an enzyme activator, plays a role in _____________
, and helps in transport of ions across cell
membranes.
 Serum calcium levels vary with serum protein and
albumin levels (these levels should be
_____________ with increased serum calcium)

Calcium (cont’d)
______________________: seen with
hyperparathyroidism, excessive vitamin __
intake, bony ______________.
 ______________________: seen in
malabsorption, ____________, pancreatic
necrosis, hypoalbuminemia,
hypoparathyroidism, gastrointestinal
__________ or blockage in ruminants,
postparturient ________________ in cow,
bitch, ewe, and mare.

Inorganic Phosphorus
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Most phosphorus in whole blood is found within the
RBCs as _______________ phosphorus
Phosphorus in plasma and serum is _____________
phosphorus and is the phosphorus assayed in the
laboratory
Plasma or serum phosphorus and calcium concentrations
are _____________ related: as phosphorus
concentrations decrease, calcium concentrations
___________.
___________________ samples should not be used
because organic phosphorus liberated from
______________ may be hydrolyzed to inorganic
phosphorus, which results in a falsely ______ inorganic
phosphorus concentration.
Inorganic Phosphorus
______________________________: may be
seen in renal failure, ________, excessive
vitamin __ intake, ethylene glycol poisoning,
and hypoparathyroidism.
 ______________________________: may
occur in primary hyperparathyroidism,
____________________, inadequate intake,
hyperinsulinism, _____________________,
lymphosarcoma, hyperadrenocorticism

Sodium
Most abundant ______________ cation that
plays a major role in the distribution of
___________ and the maintenance of
_____________ pressure of fluids in the
body.
 If ________ is retained, _____ is retained.
 Sodium heparin should not be used as an
anticoagulant because it may falsely _____
results.

Sodium (cont’d)
_______________________ is rare unless
the animal is deprived of ________.
 _______________________ is quite
common and is seen in such conditions as
________ failure, __________, or diarrhea;
use of diuretics; excessive ____; congestive
heart failure; water toxicity; or excessive
________ administration.

Potassium
Major _______________ cation; important for
normal _______________ function, nerve impulse
transmission, and ________________ metabolism.
 __________ levels are so ____ that measurement
of serum potassium does not give much information
about the body’s potassium levels.
 ___________ is the preferred sample because
platelets may release potassium during the clotting
process (elevating K+ levels).
 ______________ releases potassium into plasma
(elevating K+ levels).

Potassium (cont’d)
______________________: will be seen in
adrenal cortical hypofunction,
____________, or late-stage ________
failure.
 ______________________: will be seen in
____________, ____________ therapy, or
excess fluid _________ due to diuretics,
vomiting, and diarrhea.

Magnesium





Functions to activate _____________ systems and
involved in production and decomposition of
acetylcholine
__________ and ________ are the only domestic
animals that show clinical signs related to magnesium
deficiencies.
Imbalance in __________ -_____________ ratio
can lead to muscle _________ in cattle and sheep
Anticoagulants other than ___________ may
artificially decrease results
________________ may elevate the results
through liberation of magnesium from RBCs
Chloride





Predominant ________________ ion.
Functions in maintenance of _______ distribution,
____________ pressure, and the normal
________/_________ ratio.
Concentration is regulated by the ___________.
There is a close relationship between ________
and ___________ levels
______________ may affect test results by
diluting the sample with RBC fluid
Chloride (cont’d)
_______________________: may be due to
metabolic ___________ or renal tubular
acidosis
 _______________________: may be due to
excessive ___________ , anorexia,
________________, or diabetes insipidus,
or may accompany hypokalemia.

Bicarbonate
Second most common __________ of plasma.
Functions in the bicarbonate/carbonic acid
__________ system and aids in the transport of
____ from the tissues to the lungs.
 Kidney regulates bicarbonate levels in the body by
excreting excesses after it has ____________ all
that it needed.
 Levels are frequently estimated from blood carbon
dioxide levels (___________ blood = best)
 Bicarbonate level is approximately ___% of the total
carbon dioxide measured.
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