Clinical Laboratory Testing – Basic Clinical Chemistry
Purpose of Clinical Chemistry Tests
:‫االغراض التي تعمل الجلها تحاليل الكيمياء السريرية‬
1. Measure levels of substances found normally in human blood that
have biological functions. Examples: Glucose, Calcium
2. Detect or measure non-functional metabolites or waste products.
Examples: Creatinine, Blood Urea Nitrogen (BUN)
3. Detect or measure substances that indicate cell damage or disease.
Examples: Liver enzymes, such as ALT, Cardiac enzymes, such as CKMB
4. Detect or measure drugs or toxic substances. Examples: Dilantin,
Drugs of abuse screen
 Types of Specimens for Chemical Analysis
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:‫انواع العينات المستخدمة في تحاليل الكيمياء السريرية‬
Whole blood, serum or plasma. The most common specimen is
serum, collected in a tube with no anticoagulant so that the blood will
clot.
Urine – often 24 hour collections
Others – Cerebrospinal Spinal Fluid (CSF) and other fluids
 Collection and Handling of Blood Specimens for Chemical Analysis
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Blood collection tubes for obtaining serum - Serum Separator
Tubes (SST) do not have an anticoagulant but do contain a gel
substance which will form an interface between the clot and the
serum when the blood specimen is centrifuged.
Patient preparation; time of collection; & effects of eating on
chemistry analysis
 Some specimens are increased or decreased after eating
(ex. Glucose, triglycerides), so it is important to know what
the test and collection method call for. Specimens for
these tests are usually collected in a fasting state.
 Sometimes serum or plasma appears lipemia (milky) after a
patient has eaten a fatty meal. Lipemia affects most
chemistry analyses. The blood must be recollected when
the patient is fasting.
 Clinical Chemistry Tests
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Normal or Reference Values – range of values for a particular
chemistry test from healthy individuals
Chemistry Panel grouping – some tests are “bundled” according to
the system or organ targeted. Examples: thyroid panel, liver panel,
cardiac panel, kidney panel, basic metabolic panel, etc.
 Commonly Performed Chemistry Tests or Analytes
‫بعض التحاليل الكيميائية المهمة والشائعة‬
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Proteins – essential components of cells and body fluids. Some made
by body, others acquired from diet. Provides information about state
of hydration, nutrition and liver function, since most serum proteins
are made in the liver.
Electrolytes – sometimes called “lytes”
 Includes sodium (Na), potassium (K), chloride (Cl) and
bicarbonate (HCO3-)
 Collectively these have a great effect on hydration, acidbase balance and osmotic pressure as well as pH and heart
and muscle contraction
–
 Levels differ depending on if inside vs. outside cells
 Important in transport of substances into and out of cells
Minerals ‫المعادن‬
 Calcium
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Used in coagulation and muscle contraction
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Hypercalcemia – occurs in parathyroidism, bone
malignancies, hormone disorders, excessive vitamin D,
and acidosis; may cause kidney stones
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99% is in skeleton and is not metabolically active
Influenced by vitamin D, parathyroid hormone,
estrogen and calcitonin
Hypocalcemia – can cause tetany; occurs in
hypoparathyroidism, vitamin D deficiency, poor dietary
absorption and kidney disease
 Phosphorus
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80% in bone and rest in energy compounds such as ATP
–
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Essential for hemoglobin
–
Increased in hemolytic anemia, increased iron intake or
blocked synthesis of iron-containing compounds, such
as in lead poisoning
 I r on
–
Influenced by calcium and certain hormones
Deficiency results in anemia; may be caused by lack of
iron in diet, poor absorption, poor release of stored
iron or loss due to bleeding
Kidney Function Tests
 Serum Creatinine
–
Best test for overall kidney function; not affected by
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diet or hormone levels
Waste product of muscle metabolism
Serum creatinine rises when kidney function is
impaired
 BUN (Blood Urea Nitrogen)
–
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BUN is surplus amino acids that are converted to urea
and excreted by kidneys as a waste product
BUN influenced by diet and hormones, so it is NOT as
good an indicator of renal function as serum creatinine
levels
BUN increased in kidney disease, high protein diet, and
after administration of steroids
BUN decreased in starvation, pregnancy and in persons
on a low protein diet
 Uric Acid
–
–
–
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Formed from breakdown of nucleic acids and excreted
as a waste product by kidneys
Increased in kidney disease, but most often used to
diagnosis gout (pain in joints, mainly big toe, due to
precipitated uric acid crystals)
Also increased in increased cell destruction, such as
after massive radiation or chemotherapy
Liver Function Tests
 Liver functions:
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Synthesizes glycogen from glucose
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Forms cholesterol and degrades it into bile acids,
Makes plasma proteins (albumin, lipoproteins,
coagulation proteins)
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which emulsifies fats for absorption
Stores iron, glycogen, vitamins and other substances
Destroys old blood cells and recycles components of
hemoglobin
 Total Bilirubin
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Waste production of hemoglobin breakdown
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Alkaline Phosphatase (ALP or AP) - Greatly increased in
liver tumors and lesions; moderately increased in
diseases such as hepatitis
Increased in excessive RBC breakdown, such as
hemolytic anemia, or impaired liver function or some
sort of obstruction, such as a tumor or gall stone
 Liver Enzymes – levels increase following damage to liver
tissues
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Alanine Aminotransferase (ALT; formerly called SGPT)
- Increases up to 10x in cirrhosis, infections or tumors
and up to 100x in viral or toxic hepatitis
Asparate Aminotransferase (AST; formerly called
SGOT) - Increased in liver disease, but also in heart
attacks
Gamma Glutamyl Transferase (GGT) - Often used to
monitor patients recovering from hepatitis and
cirrhosis
Lactate Dehydrogenase (LD) - Increased in liver
disease and following heart attacks
 Cardiac Function Tests
–
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Creatine Kinase (CK) - Widely used to diagnosis and
monitor heart attacks
Troponins
 Only present in heart muscle, making it a more
accurate indicator of heart attack than CK
 Cardiac Troponin T (cTnT)
 Cardiac Troponin I (cTnI)
 Lipid Metabolism Tests
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Cholesterol
 Present in all tissues
 Serves as the skeleton for many hormones
 Recommended to be less than 200 mg/dL in
adults)
 LDL = “bad” cholesterol; HDL = “good” cholesterol
Triglycerides
 Main storage form of lipids, comprising 95% of
fat tissue
 Hyperlipidemia – having high blood levels of
triglycerides – may increase risk of heart attack
 Carbohydrate Metabolism Tests
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Glucose - Largely regulated by insulin
 Thyroid Function Tests
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Thyroid Stimulating Hormone (TSH) - Inverse
relationship to thyroid function (the higher the TSH,
the lower the thyroid function and vice versa)
Other less common thyroid tests include T3 and T4
Hypothyroidism – underactive thyroid gland
Hyperthyroidism – overactive thyroid gland
‫انتهت محاضرة التحاليل الكيميائية االساسية‬
Spectrophotometer
Spectrophotometer (Spec)
 An instrument that measures the amount of light that passes through
(is transmitted through) a sample.
Uses a type of light to detect molecules in a solution
Light is a type of energy, and the energy is reported as
wavelengths, in nanometers (nm).
Two different types of Spectrophotometer:
Ultraviolet (UV) Spectrophotometers.
 Uses ultraviolet light of wave lengths from 200 nm to 350 nm.
Visible (VIS) Light Spectrum Spectrophotometers.
 Uses visible light (white light) of wave lengths from 350 nm to 700
nm.
‫كيف يعمل جهاز السبكتروفوتوميتر‬
Shines a beam of light on a sample.
The molecules in the sample interact with the light waves in of 3 ways:
 Absorb the energy
 Reflect the energy
 Transmit the energy between and through the atoms and molecules
of the sample.
‫لون االشياء يمثل الطيف الضوئي المعكوس من قبل الجزيئات فالصندوق االزرق يعني ان جزيئاته امتصت‬
.‫جميع االلوان وعكست اللون االزرق فقط‬
How a spectrophotometer works:
Consider blue molecules, all the wavelengths of light are absorbed,
except for the blue ones.
The blue wavelengths are transmitted or reflected off the molecules.
If these blue wavelengths hit a detector (such as in the
spectrophotometer or the nerve cells in your eye), they appear blue.
Molecules are whatever color of light that they do not absorb.
Green molecules appear green because they absorb most wavelengths
of visible light, except the green wavelengths.
The spectrophotometer measures the amount of light transmitted
through the sample (Transmittance).
The concentration of an unknown sample can be determined by
comparing the absorbance data to standards of known concentration.
The data generated with the set of known standards is called a
standard curve.
Parts of a spectrophotometer
Inner parts
 Lamp
 Prism or grating that direct light of a specific wavelength.
VIS Spec vs. UV spec
Visible spectrophotometer
 Contains a tungsten lamp that produces white light.
Ultraviolet spectrophotometer
 Contains a deuterium lamp that produces light in the UV light part
of the spectrum.
Parts of a Spectrophotometer
Outer parts:
How a spectrophotometer works:
Visible Spectrophotometer
 White light hits the prism or grating, it is split into the colors of the
rainbow (Visible Spectrum).
 The wavelength knob rotates the prism/grating, directing different
color of light toward the sample.
How a spectrophotometer works:
The wavelength of light produced by the tungsten lamp range from
about 350 nm (Violet light) to 700 nm (red light).
The molecules in the sample either absorb or Transmit the light
energy of one wavelength or another.
How a spectrophotometer works:
The detector measures the amount of light being transmitted by the
sample and reports that value directly (% transmittance) or converts it
to the amount of light absorbed in absorbance units (au) using Beers
Law.
The function of a spectrophotometer
The spectrophotometer can
measure the amount of absorbance
or
lack of absorbance of different colored light for a given molecule.
The relationship of concentration in a solution:
The concentration of molecules in a solution affects the solution’s
absorbance.
 If there are more molecules in one solution than in another, than
there are more molecules to absorb the light.
Applications of a spectrophotometer
Determines the presence and concentrations of samples.
Determines the purity of a sample.
Look at the change of samples over time.
‫انتهت محاضرة السبكتروفوتوميتر‬
Definitions:
•
Quality Control:-
… to ensure the reliability of the test results to give the best patient care !
Unreliable Performance ?
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Potential consequences include:-
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patient misdiagnosis
delays in treatment
increased costs
•
avoidable retests cost US 200million USD per year
Error Classification..
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Pre-analytical:errors before the sample reaches the laboratory
Analytical:errors during the analysis of the sample
Post-analytical:errors occurring after the analysis
Pre - Analytical Errors..
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Improper preparation of the patient:-
Other Factors..
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The sex of the patient
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male or female
The age of the patient
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new born / juvenile / adult / geriatric
Dietary effects
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low carbohydrate / fat
high protein / fat
When the sample was taken
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early morning urine collection pregnancy testing
Patient posture
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urinary protein in bed-ridden patients
Other Factors..
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Effects of exercise
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creatine kinase / CRP
Medical history
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heart disease / diabetes / existing medication
Pregnancy
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hormonal effects
Effects of drugs and alcohol
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liver enzymes / dehydration
Analytical Errors..
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The sample:
Glassware / pipettes / balances:
The application:
The instrument:
Other Factors..
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Calculation errors:
– incorrect factor / wrong calibration values
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Transcription errors:
Dilutions errors:
– incorrect dilution or dilution factor used
Lack of training:
The human factor:
– tiredness / carelessness / stress
Post - Analytical Errors..
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The prompt and correct delivery of the correct report on the correct patient
to the correct Doctor.
How the Clinician interprets the data to the full benefit of the patient.
Accuracy ?
How correct your result is.
Precision ?
The reproducibility of your results.
Accurate and Precise..
Imprecise but Accurate !
Precise but Inaccurate !
Specificity ?
•
The ability of a method to measure solely the component of interest. (No
false +ve)
Sensitivity ?
•
The ability to detect small quantities of a measured component. (No false –
ve)
How can Analytical
Quality be Controlled ?
•
Internal Quality Control (IQC).
– daily monitoring of quality control sera using samples of known
values.
•
External Quality Assessment (EQA).
– comparing of performance to other laboratories.
Internal Quality Control..
•
Daily monitoring
•
Quality control sera
– precision
– accuracy
– results within control limits indicates that analytical system is
running satisfactorily
‫انتهت محاضرة السيطرة النوعية‬
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Basic Clinical Laboratory Math
Metric System
Most countries use the metric system for measurement
 Examples:
– Gasoline by liter
– Body weight in kilograms
– Distance in meters or kilometers
U.S. uses English system of measurement in everyday life
 Examples:
– Gasoline in gallons
– Weight in pounds
– Distance in miles
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Metric System
English system of measurement is not accurate enough for
most scientific measurements
Because metric system is a decimal system, it can be used for
very small quantities with accuracy
International System of Units (SI) is a form of the metric
system adopted for use by the worldwide scientific
community.
Units of Metric System
Base Units
 Distance = meter (m)
 Mass or Weight = gram (g)
 Volume = liter (L)
Prefixes are used to indicate larger or smaller quantities of
the base units above
Common Metric Prefixes
–
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Kilo (k) = 1000 x base unit
Centi (c) = .01 x base unit
Milli (m) = .001 x base unit
Micro (µ) = .000001 x base unit
Nano (n) = 10 -9 x base unit
Pico (p) = 10-12 x base unit
Converting within Metric System
Move decimal to left
Move decimal to right
Example:
Convert Kilograms to Grams: Move decimal 3 places to right
‫ غرام‬1000 ‫ كل كيلو غرام هو‬: ‫مثال‬
‫ ملليلتر‬1000 ‫كل لتر هو‬
‫ سنتيمتر‬100 ‫كل متر هو‬
Example:
Convert Centimeters to Meters: Move decimal 2 places to left
SI System
(International System)
 Base Units of the SI System
– Length = Meter (m)
– Mass = Kilogram (kg)
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Time = Second (s)
Amount of Substance = Mole (mol)
Electric Current = Ampere (A)
Temperature = Kelvin (K)*
Luminous Intensity = Candela (cd)
Volume = Liter (L)**
Dilutions for the Clinical Laboratory
 Dilution = making weaker solutions from stronger ones

Example: Making orange juice from frozen concentrate. You mix
one can of frozen orange juice with three (3) cans of water.
Dilutions are expressed as the volume of the solution being
diluted per the total final volume of the dilution
In the orange juice example on the previous slide, the dilution
would be expressed as 1/4, for one can of O.J. to a TOTAL of
four cans of diluted O.J. When saying the dilution, you would say,
in the O.J. example: “one in four”.
 Another example:
If you dilute 1 ml of serum with 9 ml of saline, the dilution would be
written 1/10 or said “one in ten”, because you express the volume of
the solution being diluted (1 ml of serum) per the TOTAL final
volume of the dilution (10 ml total).
 Another example:
One (1) part of concentrated acid is diluted with 100 parts of water.
The total solution volume is 101 parts (1 part acid + 100 parts
water). The dilution is written as 1/101 or said “one in one hundred
and one”.
 Notice that dilutions do NOT have units (cans, ml, or parts) but are
expressed as one number to another number
Example: 1/10 or “one in ten”
 Dilutions are always expressed with the original substance diluted as
one (1). If more than one part of original substance is initially used,
it is necessary to convert the original substance part to one (1) when
the dilution is expressed.
Example:
Two (2) parts of dye are diluted with eight (8) parts of diluent (the
term often used for the diluting solution). The total solution volume
is 10 parts (2 parts dye + 8 parts diluent). The dilution is initially
expressed as 2/10, but the original substance must be expressed as
one (1). To get the original volume to one (1), use a ratio and
proportion equation, remembering that dilutions are stated in terms
of 1 to something:
______2 parts dye
= ___1.0___
10 parts total volume
x
2x
=
10
x
=
5
The dilution is expressed as 1/5.
Serial Dilutions
 Dilutions can be made singly (as shown previously) or in series, in
which case the original dilution is diluted further. A general rule
for calculating the dilution of solutions obtained by diluting in a
series is to MULTIPLY the original dilution by subsequent dilutions.
 Example of a serial dilution:
 In the serial dilution on the previous slide, 1 ml of stock solution is
mixed with 9 ml of diluent, for a 1/10 dilution. Then 1 ml of the 1/10
dilution is mixed with another 9 ml of diluent. The second tube also


has a 1/10 dilution, but the concentration of stock in the second
tube is 1/10 x 1/10 for a 1/100 dilution.
Continuing with the serial dilution, in the third tube, you mix 1 ml of
the 1/100 dilution from the second tube with 9 ml of diluent in the
third tube. Again you have a 1/10 dilution in the third tube, but the
concentration of stock in the third tube is 1/10 x 1/10 x 1/10 for a
1/1000 dilution.
This dilution could be carried out over many subsequent tubes.
 Serial dilutions are most often used in serological procedures, where
technicians need to make dilutions of patient’s serum to determine
the weakest concentration that still exhibits a reaction of some
type. Example of determining a titer:
A technician makes a serial dilution using patient serum:
Tube #1 = 1/10
Tube #2 = 1/100
Tube #3 = 1/1000
Tube #4 = 1/10,000
Tube #5 = 1/100,000
Reactions occur in tubes 1 through 3, but NOT in tubes 4 or 5. The
titer = 1000.
‫انتهت محاضرة الرياضيات المختبرية‬
Basic Principles of Phlebotomy
Modern Phlebotomy
•
D i a g no s i s a n d m a n a g e m e n t o f d i s e a s e
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Remove blood for transfusions
•
Therapeutic reasons:
– Polycythemia
– Hemochromatosis
Blood Function:
•
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Supplies nutrients to tissues:
O2, hormones, glucose
Removes end-products of metabolism:
CO2, urea, creatinine
Provides defense mechanism: WBC, antibodies
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Prevents blood loss:
platelets, coagulation proteins
Blood Composition:
Formed elements (~45%)
– RBC
– W BC
– P l a te l e ts
Liquid elements(~55%)
Coagulation:
•
In v i v o
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B l o o d i s fl u i d
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Clot is formed to
protect injured vessel
In vitro
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S p o n ta n e o u s r e a c ti o n
Triggered by glass or poor drawing technique
Coagulation Reaction:
Clotting factors + calcium  thrombin
Fibrinogen + thrombin
Anti-coagulants:
•
•
fibrin strands
Remove calcium (Like EDTA)
Neutralize thrombin (Like heparin)
S am pl es us ed i n l ab
•
•
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W hol e bl ood
P l as m a
Serum
Blood with anticoagulant:
•
Clotting is prevented and irreversible, after collection mix: completely
invert 8-10 times, we will have whole blood. After centrifugation 
plasma. Plasma contains fibrinogen
Blood without anticoagulant:
•
Spontaneous clotting occurs and is irreversible, Fibrinogen in blood 
fibrin strands. After centrifugation  serum. Serum lacks fibrinogen
Appearance
•
Normal: clear and ‘yellow’
•
Abnormal:
– Hemolyzed = pink to red (ruptured RBC)
– Icteric = dark orange-yellow (bilirubin)
– Lipemic = cloudy (fat, triglycerides)
Blood Collection Tubes:
•
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C o n t ai n a v a c u u m
Used with Vacutainer and Syringe systems
Type and Amount of Specimen:
•
D e p en d e n t u p o n
– Test
Whole blood: EDTA or heparin?
Plasma: EDTA or heparin?
Serum: trace free? Separator gel interference?
– Amount of sample needed to perform test
– M u l ti p l e l a b s n e e d i n g th e s a m e s p e c i m e n a t th e s a m e ti m e
Valid Test Results Require:‫ما هي المستلزمات المطلوبة للحصول على نتائج صحيحة؟‬
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Trained personnel
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Causes of pre-analytical error
Invalid test results
Quality control
Quality assurance
S o p hi s t i c a t e d
instruments
Safety Practices: ‫الممارسات الصحيحة للسالمة المختبرية‬
For infection to spread:
•
Infectious substance: HBV, HCV, HIV
•
•
Mode of transmission
S u s c e p ti b l e h o s t
Modes of Transmission:
•
Parenteral: any route other than the digestive tract
– Intramuscular
– Intravenous
– S u b c u ta n e o u s
– M uc os al
•
I n g e s ti o n
S a fe t y P r a c ti c e s :
Infection Control: stop the spread of infection
Safety: Infection Control
•
Hand washing
– Primary means of preventing spread of infection (especially
no s o c o m i a l )
•
•
– Minimum 15 seconds, soap, friction
– Wash hands before and after each blood draw
We should wear
– La b c o a t
– Gloves
– M as k
Cleaning agent ‫المعقمات‬
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Alcohol pads: routine
Povidone iodine: blood culture collection and blood gases
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Soap and water: alcohol testing, allergies
Cotton balls, gauze
E q u i p m e nt :
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Bandage, tape (use caution with children)
•
Sharps container:
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Discard needles,
l a n c e ts
Biohazard marking
Puncture resistant
NEVER recap, bend
break needles
E q u i p m e nt :
6.
Tourniquets:
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Slows venous blood flow down
Causes veins to become more prominent
NEVER leave on for >1 minute
AVOID rigorous fist clenching or hand pumping (potassium,
lactic acid, LD)
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Latex allergy
Tying on the Tourniquet:
E q u i p m e nt :
7.
Needles
–
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NEVER reuse a needle
NEVER use if shield is broken
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NEVER recap, cut, bend or break
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Drop immediately into sharps container after venipuncture
–
Size of needle is indicated by gauge:
• Larger gauge number indicates smaller needle diameter
• 21, 23 gauge needles routinely used for phlebotomy
E q u i p m e nt :
8.
Tube holder/
v a c u ta i n e r a d a p t e r
–
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Threaded
Flanges
E q u i p m e nt :
•
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Syringe
B l ac k
water proof
p en
Syringe Safety Device:
Labeling Blood Collection Tubes:
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Black indelible marker (water proof)
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Never pencil
Legal document
Print legibly
Required information: 5 items
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Full Patient name
Id e n ti fi c a ti o n n u m b e r
Date of draw (mm,dd,yyyy)
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Time of draw (military time)
Phlebotomist signature: first initial, last name
Vacutainer or Syringe?
•
Vacutainer
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Syringe
– M o s t o fte n u s e d
– M os t ec onom i c al
– Quick
– Least risk of accidental needle stick
– More control
– Reposition easily
– Will see ‘flash’ of blood in syringe hub when vein successfully
entered
The Patient:
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Approach
C o m m u n i c a ti o n
E m p at h y
H a n dl i n g s p e c i a l s i t u a t i o n s
P a t i e nt i d e n t i f i c a t i o n
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Arm band
Le g a l d o c u m e n t
Prepare patient for blood draw
–
Latex allergy?
S e l e c ti n g th e S i te :
•
Antecubital area most often accessed
•
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Hand or wrist
R e m em b e r : 2 a r m s
Use tip of index finger on non-dominant hand to palpate area to feel for
t h e v ei n
Collection Site Problems:
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•
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V e i n s th a t l a c k
resiliency
Extensive
scarring
H e m at o m a s
E d e m a to u s
area
•
S i d e of m a s t e c t o m y
Collection Site Problems:
•
Intravenous line
–
NEVER draw above an IV
–
Draw from other arm
–
Draw from hand
on other arm
–
Draw below the IV
Draw Below IV site:
Inserting the Needle:
•
A n c h or t h e v e i n
–
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Grasp arm with your non-dominant hand
Use thumb to pull skin taut
Smoothly and confidently insert the needle bevel up
–
15-30 degree angle
No Needle Movement!
•
You must anchor the blood-drawing equipment on the patient’s arm to
m i ni m i z e c hanc e o f i nj ur y
Withdraw Needle:
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•
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First release tourniquet
D i s e ng a g e t u b e
Place cotton directly over needle, without pressing down
Withdraw needle in swift, smooth motion
Immediately apply pressure to wound
Do not bend arm
Needle Position:
You should try again
•
•
•
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Look at alternate site
–
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Other arm
Hand
U s e c l ean needl e
Use fresh syringe if contaminated
Only try twice
Poor Collection Techniques:
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V e n ou s s t a s i s
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Prolonged application of tourniquet (>1 min)
H e m od i l u t i o n
–
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Drawing above IV
Short draw (blood to anticoagulant ratio)
Hemolysis
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Traumatic stick
Too vigorous mixing
Alcohol still wet
Using too small of needle
Forcing blood into syringe
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C l o t t ed s a m p l e
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Partially filled tubes
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Using wrong anticoagulant
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S pec i m en handl i ng
– Inadequate mixing
– Traumatic stick
– Short draw
– Sodium citrate tube draw volume critical
– Exposure to light (Bilirubin)
– Pre-chilled tube
– Body temperature
Venipuncture Procedure:
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W as h hands
P u t on g l o v e s
I d e n ti f y p a ti e n t
Latex allergy?
Position arm
A p p l y to u r n i q u e t
Venipuncture Procedure:
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Locate vein
Release tourniquet
Cleanse site in outward rotation
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A l l o w to a i r d r y
Reapply tourniquet
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Do not contaminate site
A n c h or v e i n
Insert needle
Fill tubes
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Quick mix additive tubes
Release tourniquet
Withdraw needle
E n g ag e s a f e t y d e v i c e
D i s p os e o f n e e d l e i m m e d i a t e l y
Apply pressure to puncture site
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L a b e l tu b e s
R e c he c k p u n c t u r e s i t e
Thank patient
R e m ov e g l o v e s ,
wash hands
‫انتهت محاضرة سحب الدم‬