Introduction to Clinical Chem Flashcards
Branch of laboratory medicine that is concerned with the quantitative measurement of analytes in body fluids to facilitate the diagnosis of diseases
Clinical Chemistry
They are biologically important substances. It includes ions, salts and minerals, small organic molecules, and large macromolecules. It also includes carbohydrates, proteins, lipids, enzymes, metabolites, vitamins, and drugs
Analytes
Purpose of testing for these analytes is to assist the clinicians in making a diagnosis, monitor disease progression and guide treatment decisions.
TRUE OR FALSE
TRUE
It is USUAL that results from a single laboratory assay will provide a diagnosis
TRUE OR FALSE
FALSE
UNUSUAL
Additional tests may be needed in order to take the decision making to the next step
TRUE OR FALSE
TRUE
When the results of this tests are used appropriately, in the context of the medical history and physical examination findings of the patient, the decision making of the doctor or clinician is improved
TRUE OR FALSE
TRUE
It can also be used to monitor the disease over time and to check if treatment is effective or working
TRUE OR FALSE
TRUE
Clinical Chemistry examines various analytes using different methodologies, and is fully-automated.
TRUE OR FALSE
FALSE
Methodologies are both manual and fully-automated. Technological advances in this field are intertwined with developments in automations and the clinical laboratory
The scope of clinical chemistry encompasses many scientific disciplines such as:
Analytical Chemistry
Biochemistry
Instrumentation and Computers
Endocrinology
Immunology
Pharmacology
Toxicology
Other
It is the science of obtaining, processing, and communicating information about the composition and structure of matter
Analytical Chemistry
It is the branch of science that explores the chemical processes within and related to living organisms
Biochemistry
In clinical chemistry, the analysis involves both manual and automated methods. The productivity of the chemistry laboratory depends heavily on instrumentation
What is being talked about here?
Instrumentation and Computers
Decades ago, DOCTORS usually prepared Protein Free Filtrate (PFF) in small glass jars before proceeding with the test. But now, it has been replaced with modern analytical devices
TRUE OR FALSE
FALSE
MEDICAL TECHNOLOGISTS
By using modern instruments, analysis becomes faster and more efficient. They are also COST-HEAVY in long term
TRUE OR FALSE
FALSE
THEY ARE COST-EFFECTIVE
Progress of the clinical chemistry has been influenced to a great extent by the development of instrumentation
TRUE OR FALSE
TRUE
There is no automated system today that can function without computers
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TRUE
Computers are not only responsible for giving instructions, but also control the operation of the entire system
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TRUE
Example. It gives warning when there is malfunction
This is concerned with the hormones, endocrine glands, and endocrine disorders
Endocrinology
The study of defense mechanisms that protect humans from foreign invaders
Immunology
The study of mechanism of drug action and therapeutic uses of drugs
Pharmacology
The science that helps us understand the harmful effects of chemicals and substances to humans
Toxicology
Important factor in toxicology is the dose of drugs or chemicals because ALL substances have the potential to be toxic in certain conditions and at certain doses
TRUE OR FALSE
TRUE
Example: Two aspirin tablets is okay for one patient, but is considered as toxic to others
The purpose of performing these tests is to confirm or to reject a diagnosis. They are used in conjunction with the medical history and the physical examination findings in order to make medical decisions
Chemistry Tests
Almost ONE-FOURTH of laboratory investigations are composed of chemistry tests
TRUE OR FALSE
FALSE
ITS ONLY ONE-THIRD
These are laboratory tests for evaluation of disorders of renal, water, electrolyte, and acid-base status.
Chemistry Tests
Screening tests are often grouped together in a basic metabolic panel.
TRUE OR FALSE
TRUE
is one of the major consequences of common disorders such as diabetes and hypertension.
Renal Disease
The blood sample is tested for the amount of _____ to diagnose Diabetes mellitus
GLUCOSE
is a metabolic disorder characterized by hyperglycemia
Diabetic mellitus
The blood sugar increases because there is a lack of secretion of insulin. This indicates?
hyperglycemia
▪ Waste products of metabolism
▪ When the blood levels of these substances increase, there
is a problem with the excretory function of the kidneys
Urea, Creatinine, Uric acid
The main function of kidney is to eliminate waste products from the blood and excrete this in the form of urine
TRUE OR FALSE (TAENA WAG NIYO MALIIN TOH)
TRUE
Body fluid that contains both organic and inorganic substances which are dissolved in water
Urine
Assess the excretion and retention capability of the kidneys
Renal Function Tests
Like: Urea, Creatinine, Uric acid
These tests evaluate the functions of the liver.
Liver profile/Hepatic panel
Which consist of: Bilirubin, Albumin, Total Protein, Alkaline Phosphatase (ALP), Aspartate Transferase (AST) , Alanine Transferase (ALT)
Functions of the liver:
- Detoxification
- Excretory function
- Synthetic function
- metabolism of proteins, fats, and carbohydrates
when an individual test is not sufficient to assess a medical condition, a combination of several tests may be used
Panel
The pattern of results from the combination of the tests may provide a better insight into the status of the patient as compared to the result of a single test result alone
TRUE OR FALSE
TRUE
This test is aimed at providing information about the state of the patient’s liver
Liver profile/Hepatic panel
It is used to measure the amount of fats or lipids in the blood, used to screen abnormalities in the lipids, and to assess the risk of the patient in developing heart diseases.
Lipid profile/panel
Triglycerides, Total cholesterol, HDL cholesterol, LDL cholesterol
Enzymes are proteins
TRUE OR FALSE
TRUE
Amylase, Lipase, Creatine Kinase
These are all examples of?
Enzymes
They are produced at a certain organ of the body. So, when there is a damage to that particular organ, then it will alert us to the possibility that it is the reason for the elevation of that particular enzyme in the blood
Enzymes
Responsible for regulating water content and osmotic pressure or osmolality
Electrolytes
major extracellular cation
Sodium
major intracellular cation
Potassium
major extracellular anion
Chloride
Hormones, specific proteins, trace elements, vitamins, drugs, lipoproteins are all?
Specialized Tests
These are complex tests that are too expensive for the laboratory. Some laboratories send out samples to reference laboratories who can carry out these tests.
Specialized Tests
They are not routinely performed and need special equipment for the test. Not all laboratories have the capability to perform these tests
Specialized Test
The specimens which are submitted in the chemistry section include the blood which is the most common, followed by urine, CSF, and other bodily fluids.
Clinical Specimens
Most common specimen that is received in the laboratory
Blood
2 parts of blood
Plasma and Cellular portion
fluid portion that contains dissolved ions and molecules
Plasma
What is being described?
▪ This is where most chemistry analytes are found.
▪ Part of the preparation of blood for testing these analytes
involves removing the cells.
▪ This is done by the centrifugation of the sample in order to
pack the cells at the bottom of the collection tube and to
allow for the removal of the plasma or serum for testing.
Plasma
Part of blood composed of RBC, WBC, and platelets
Cellular portion
Blood specimens are collected through venipuncture or phlebotomy.
TRUE OR FALSE
TRUE
Most common puncture site for blood collection
antecubital fossa
TRUE OR FALSE
o Blood will go directly to an evacuated tube
o This tube will hold 10mL of blood which is just enough to
perform many tests since automated analyzers require
only small amounts for single test
FALSE
The evacuated tube tube should only hold 5mL of blood
For obese patients or patients with poor veins, skin or capillary puncture is performed
TRUE OR FALSE
TRUE
o In ______ _______, the fleshy part of the fingertip is pricked
with a lancet
o We use the 2nd, 3rd, or 4th finger
o The blood is collected in a capillary tube or in a
microtainer tube
Capillary puncture
For infants, blood collection is through heel puncture.
TRUE OR FALSE
TRUE
Blood can also be collected from the artery, this method is known as
Arterial Puncture
Sites for arterial puncture include the
radial, brachial, and femoral arteries
Analysis is performed using gas in arterial blood
Arterial Blood Gas (ABG)
The parameters that are being measured for ABG(Arterial Blood Gas) are:
▪ partial pressure of oxygen
▪ partial pressure of carbon dioxide
▪ pH oxygen saturation
▪ pH carbon dioxide saturation
Test that assess collateral blood circulation. To determine if the site of puncture has other blood supply aside from it
Allen’s Test
collected in a tube CONTAINING an anticoagulant which is an additive that prevents blood clotting
Plasma
collected in a tube WITHOUT an anticoagulant, the blood will form a clot
Serum
▪ Contains fibrinogen
▪ Ex. When you extract and draw a blood with an
anticoagulant tube (citrated tube or lavender top tube)
and you centrifuge the sample, there will be a separation
of the solid and liquid portion
Plasma
Solid portion of unclotted blood is the plasma
▪ Has no fibrinogen because it has been exhausted or
used up during the clotting or coagulation process
▪ Upon centrifugation of the clotted blood, the clot will go to
the bottom of the tube, along with the cells. The liquid
portion on the top is called?
Serum
gelatinous of semi-solid mass that is composed of cross-linked protein in serum. The Cross-linked protein is formed through coagulation
Clot
➢ Composed of water and dissolved in water are the
organic and inorganic substances
➢ It is specially suitable for tests that evaluate kidney
function, waste products excreted by the kidneys, and
metabolites that are cleared from the bloodstream and
accumulated in the urine (such as drugs of abuse)
Urine
Urine is collected by midstream clean catch method
TRUE OR FALSE (WAG NIYO MALIIN TOH HAHAHA)
TRUE
o You collect the middle portion of a single continued
urination. For adults, it is relatively easy.
o Special techniques must be used for pediatric patients
midstream clean catch method
Urine can either be concentrated or dilute. The main factor affecting this is the hydration status of the PROFESSIONAL
TRUE OR FALSE
FALSE
IT SHOULD BE THE PATIENT
A difference in the concentration of the urine can affect the amount of the substances that are found in the sample at different times.
TRUE OR FALSE
TRUE
In chemistry, we usually perform a 24-hour urine collection to measure the amount of creatinine in the blood. For quantitative determination of serum or plasma creatinine
TRUE OR FALSE
TRUE
➢ The fluid that surrounds the brain and spinal cord. Acts
as a cushion that protects these structures from trauma
➢ It is crystal clear in appearance. Looks like distilled water
CEREBROSPINAL FLUID (CSF)
Specimen collection of CSF is through?
LUMBAR PUNCTURE
It is collected for patients who are suffering from meningitis, multiple sclerosis, and other neurologic disorders.
CEREBROSPINAL FLUID (CSF)
Since the manner of collecting the sample is delicate, CSF must be handled properly and must be processed as soon as possible
TRUE OR FALSE
TRUE
CSF are collected in 3 tubes which are labeled 1, 2, 3 depending on the order in which they are drawn. Identify what the tubes are used for.
Tube 1
used for Chemistry and Serology
CSF are collected in 3 tubes which are labeled 1, 2, 3 depending on the order in which they are drawn. Identify what the tubes are used for
Tube 2
used for Microbiology
CSF are collected in 3 tubes which are labeled 1, 2, 3 depending on the order in which they are drawn. Identify what the tubes are used for
Tube 3
used for performing cell counts in Hematology
CSF are collected in 3 tubes which are labeled 1, 2, 3 depending on the order in which they are drawn. Identify what the tubes are used for
Additional Tube
Cytology analysis
_____ is an ultrafiltrate of plasma. So the components of the plasma is similar to that of the _____ but differs in the concentration of the substances
CSF
In chemistry, the CSF is tested for the presence of glucose and protein
TRUE OR FALSE
TRUE
Typically used to test for congenital diseases also for neural tube defects and to assess or determine fetal maturity. This is the fluid that cushions the fetus in the mother’s womb.
AMNIOTIC FLUID
These are tested in the chemistry section in order to determine the origin of the fluid whether they are transudate or exudate.
PLEURAL FLUID, PERITONEAL FLUID, PERICARDIAL FLUID
they leak out of the blood vessels because of differences in hydrostatic pressure.
Transudate Fluid
they are the result of infection, inflammation, and malignancy.
Exudate Fluid
The POST-analytic phase is the most vulnerable phase for error.
TRUE OR FALSE
FALSE
it must be the PRE-analytic phase
Medical technologists should be able to detect these pre-analytical errors because this may lead to misdiagnosis and mismanagement of the patient
Specimens must contain 2 identifiers:
These identifiers must match the accompanying request form
o Patient’s name
o Date of birth
Note: For every specimen there must be a request form
In most request forms, it contains:
o Patient’s name
o Age
o Sex
o Date of birth
o Physician’s name
o Diagnosis
o Test requested
o Site or origin of the specimen
Microbiology and Histopathology are site specific and must be indicated in the request form
TRUE OR FALSE
TRUE
Most automated systems does NOT make use of barcode technology
TRUE OR FALSE
FALSE
automated systems do make use of barcode technology
serve as the label they are used for the positive identification of the patient and also for tracking the specimen. This is also one way of eliminating errors caused by poor handwriting or by misreading the information if the label is handwritten
Barcodes
QNS means?
quantity not sufficient
Commonly reported pre-analytical errors in the laboratory
QNS - quantity not sufficient
The specimen volume that must be submitted in the laboratory must be sufficient enough to perform the test and to perform repeat determinations if necessary
TRUE OR FALSE
TRUE
TRUE OR FALSE
➢ If you want to obtain plasma, use a tube with
anticoagulant
➢ If you want serum, there should be no additive (red top
or yellow top tube)
TRUE
TRUE OR FALSE
➢ Use of underfilled tubes can lead to erroneous results
➢ Use of overfilled tubes can lead to clotting, there is a
specified ratio and anticoagulant.
➢ There are markings which will indicate the maximum and
minimum fill line
➢ If the filling of blood stops for any reason this will result
in a partially filled tube (short draw)
TRUE
o These tubes are designed with vacuum
o When you draw blood, you allow the blood to fill the tube
until the vacuum is exhausted
It may result in increased K, Mg, P, Acid Phosphatase (ACP), Lactate Dehydrogenase (LDH), Aspartate Aminotransferase (AST)
o These chemicals are found in the plasma
o When the red blood cells rupture, these will also be
released into the blood causing its elevation
Hemolyzed sample
refers to the rupture or bursting of red blood cells
o Release of hemoglobin and intracellular contents of RBC
into plasma the resulting serum or plasma will be red in
color.
o Possibly due to poor technique in venipuncture or
excessive trauma in the blood vessel during collection
o It could also be the result of rough handling during
transport, tubes being mixed vigorously, and prolonged
contact of the red blood cells with serum or the plasma
Hemolysis
➢ It affects tests that use spectrophotometric methods
➢ Specimen has a milky white appearance due to the
presence of lipids or fats
➢ This is due to a fatty diet or the patient did not fast
enough before specimen collection.
➢ Increase absorption of light
➢ The turbid appearance of serum and plasma will interfere
with the passage of light into solution, which is known as
the Principle of spectrophotometry
➢ Removed by high speed centrifugation (10,000g) and
extraction with Trichlorofluoroethane
LIPEMIC SAMPLE
the recommended method by CLSI for lipemic samples
Ultracentrifugation
but the equipment of ultracentrifugation is expensive so not all laboratory have the capability to perform this
These are the consequences of specimen rejection
TRUE OR FALSE
➢ Repeated specimen collection
o Added cost on the part of the patient who will pay
for the assay
o Cause inconvenience
o Potential for complications
➢ Delay in analysis and reporting of results
o Increase in turnaround time
➢ Delay in treatment of patient
TRUE
Order the Laboratory workflow start to finish
Test ordered by clinican
Sample collection
Sample Transport
Result Transmission
Sample Analysis
Sample Processing
Test ordered by clinican
Sample collection
Sample transport
Sample processing
Sample analysis
Result transmission
