SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
●
OUTLINE
I.
A.
B.
C.
D.
E.
FINALS
CAPILLARY PUNCTURE
EQUIPMENTS
CAPILLARY BLOOD COMPOSITION
ORDER OF DRAW
CAPILLARY PUNCTURE STEPS
NEWBORN SCREENING
I.
●
●
CAPILLARY PUNCTURE
The process of obtaining blood by puncturing or
making an incision in the capillary bed in the
dermal layer of the skin with a lancet or other
sharp device.
○ Dermal puncture
○ Skin puncture
It can be done if the test can be performed
using small sample volumes.
Microscope slides
LANCETS
●
●
●
●
●
NOTE:
●
This capillary puncture is very useful in pediatric
patients. It is used when a small amount of
samples is needed.
A. EQUIPMENTS
●
●
●
●
●
●
Lancets or incision devices
Microcollection containers
Microhematocrit tubes
Sealants
Warming devices
Capillary blood gas equipment
A sterile, disposable, sharp-pointed or
bladed instrument.
Used to puncture the skin to obtain
capillary blood
Different lengths and depths
○ Depends on the amount of
volume needed and age of the
patient, so that it can
accommodate
various
specimen collections.
○ In selecting a lancets, obtain
the required volume without
injuring the bone of the patient.
Designed for both finger and heel
puncture
○ OSHA requires a lancet safety
feature which is a permanent
retractable blade or needle
point to reduce the risk of the
needle prick injuries.
LASER LANCETS
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
MICROCOLLECTION CONTAINERS
●
●
●
Special small plastic tubes to collect
tiny amounts of blood.
○ Also known as microtubes
○ After the capillary puncture, the
sample collected should be put
in here.
○ Referred as a bullet, because
of their size and shape.
○ Some with narrow plastic
capillary tubes to facilitate the
specimen collection.
Color-coded bodies or stoppers
Markings for maximum and minimum
fill (250-500 uL)
○ It shouldn’t be underfilled or
overfilled because the ratio of
the blood and anticoagulant is
not balance and will lead to clot
formation.
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
MICROHEMATOCRIT TUBES
●
●
●
Disposable, narrow-bored plastic or
plastic or plastic-clad glass.
○ Primarily used for manual
hematocrit determination.
Can hold 50-75 uL of blood
Color-coded bands
○ Red and green
■ Heparin
○ Blue
■ No additive
NOTE:
● When collecting venous blood and you
place it into a microcollection tube,
don’t forget to label that it is a venous
collection, because capillary puncture
and venipuncture have a different
reference range.
● When there is only a little amount of
sample collected, it is possible to put it
in a microcollection container, but
always note the type of collection you
have utilized.
SEALANTS
●
●
For sealing capillary tubes
Plastic or clay placed in small trays
○ You can place the hematocrit
tubes in the holes beside the
numbers.
WARMING DEVICES
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
●
●
●
Warms the site to increase blood flow
○ Increase blood flow means
efficient blood collection
○ Recommended
to
kids,
because it will be hard to
collect blood from them.
○ Collecting samples from a
newborn is challenging and
needs a technique.
Temperature : <42 degree celsius
Alternative:
○ Towel or diaper damped with
warm water.
CAPILLARY BLOOD GAS EQUIPMENT
○
○
Magnet
■ Both ends of CBG tubes
are sealed to prevent
exposure and air, the
magnets are used to mix
the sample
Plastic caps
■ Used to seal the CBG
tubes and to maintain the
anaerobic environment
MICROSCOPE SLIDE
●
●
The blood is dropped in the slide directly
from a capillary puncture
Microscope slide is used to make a blood
smear for hematology determination
manually.
B. CAPILLARY BLOOD COMPOSITION
●
●
To collect capillary blood gas specimens
COMPONENTS:
○ CBG collection tubes
■ Long, thin, narrow bore
capillary tubes
■ Are plastic for a safety
purpose
■ Comes in different sizes
depending on the volume
needed
■ 100 mm in length with a
capacity of 100 μL is the
common CBG tube
○
Stirrers
■ Small metal bars that are
inserted in tubes after
collection of CBG
■ For
mixing
the
anticoagulant
●
Mixture of:
○ Arterial blood
■ Enters capillaries under
a pressure
■ Capillary blood contains
a higher proportion of
the
arterial
blood
compared
to
the
venous blood
○ Venous blood
○ Interstitial fluid
■ Fluid in tissue spaces
between the cells
■ We
also
have
intracellular fluid which
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
is the fluid within the
cells
CONTRAINDICATIONS
●
●
●
●
Glucose is higher while total protein,
calcium, and potassium is lower
Potassium values are normally lower
When
collecting
samples
for
potassium, we have to be careful
because levels may be falsely
elevated
INDICATIONS FOR ADULTS
●
●
●
●
●
Veins are fragile or must be saved for
other procedures
Thrombotic
Intense fear of needles
No accessible veins
POCT procedures
INDICATIONS FOR INFANTS AND
YOUNG CHILDREN
●
●
●
Due to low total blood volume
○ Drawing too much blood could
result to anemia
○ Every 10 mL of blood drawn
from
a young child is
equivalent to 4 mg of iron is
removed
Venipuncture may damage veins
Capillary blood is the specimen
preferred
●
Tests:
○
○
○
○
○
○
Erythrocyte sedimentation rate
Coagulation studies
PT
APTT
Blood cultures
Other tests that require large
volumes of serum/plasma
Patients:
○ Dehydrated
○ Poor circulation
C. ORDER OF DRAW
●
●
●
●
Blood gas specimens
EDTA specimens
Other additive specimens
Serum specimens
➢ Puncturing the skin releases the tissue
thromboplastin, this is the one who
activates the coagulation process in
our blood so the specimens must be
collected quickly so it can minimize the
microclot formation and to get the
desirable volume of the test
➢ Specimen samples for newborn
screening
should
be
collected
separately
D. CAPILLARY PUNCTURE STEPS
1. Review and accession of test request
2. Approach,
identify,
and
prepare
request
3. Verify diet restrictions and latex
sensitivity
4. Sanitize hands and put on gloves
5. Position patient
● Finger puncture
- Place on a firm surface
- Hand extended and palm
up
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
●
Heel puncture
- Infant should be supine
- Foot lower than the torso
6. Select the puncture/incision site
● Warm
● Pink
● Free of scars, cuts, bruises, or
rashes
● Not cyanotic(bluish in color)
● Not edematous
● Not swollen
Recommended site for capillary puncture
- Palmar surface of distal end or middle of
the ring finger (orange arrow in the
picture letter a)
- Should be central portion of the finger and
slightly on the side to the center and
perpendicular of the spirals of the
fingerprints (Do not follow letter b)
-
For the infant, heel is the puncture site
and must be taken care properly because
it can be very painful which can result to
the inflammation of bone marrow and
adjacent
bone
which
we
call
osteomyelitis or osteocondritis which is
an inflammation to the bone or cartilage
as a result of infection
7. Warm the site if applicable
● To increase blood flow
● Recommended for heel stick
procedures
● Wrap the site for 3-5 minutes
-
Warming the site increases the
blood flow 7 fold and does not
significantly alter the results of the
tests.
8. Clean and air-dry the site
● 70% isopropanol should be used
● Do Not use Povidone-iodine
because affects some tests like
bilirubin, acid, phosphorus, and
potassium
9. Prepare equipment
● Select devices according to the
test, age of patient, amount of
blood to be collected and puncture
site
10. Puncture the site and discard lancet
● Hold the hand securely in case of
sudden movement
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
●
Puncture in the fleshy pad of the
finger, slightly to the side of center,
perpendicular to the fingerprint
● Heel Puncture - grasp the foot
gently but firmly with your
non-dominant hand.
● Remove the device from the skin
immediately following puncture
and discard it in a sharps container
11. Wipe Away the First Blood Drop
● Position the site downward and
apply gentle pressure toward the
site to encourage blood flow
● Prevents contamination of tissue
fluid and removes alcohol residue,
thus preventing hemolysis of the
specimen and allows the blood to
form a well-rounded drop
● In addition, there have been
reports
of isopropyl alcohol
contamination causing errors in
blood glucose testing
12. Fill and mic tubes/containers in order
of draw
● Caution: Do not squeeze, use
strong repetitive pressure, or “milk”
the site, as hemolysis and tissue
fluid
contamination
of
the
specimen can result
● Microhematocrit tubes:
○ Make sure that the tube is
only touching the blood
○ Tilt the tube in a lower
angle as it fills
○ Do not lose contact with
blood to avoid spaces
○ Do not remove the tube
from the drop or continually
hold or tip the tube below
the site
● Microcollection container:
○ Turn the patient’s hand
upside down
○ Touch the tip of the
container to the blood drop
○
○
Do not scoop against the
skin
The scoop should touch
only the blood and not the
surface of the skin. This
allows blood to be collected
before it runs down the
surface of the finger or heel
and avoids contamination.
13. Place Gauze and Apply Pressure
● After collecting specimens, apply
pressure to the site with a clean
gauze pad until bleeding stops
● Keep the site elevated while
applying pressure
● An infant’s foot should be elevated
above the body while pressure is
applied
14. Label Specimen and Observe Special
Handling Instructions
● Label the specimens with the
appropriate information
● Follow any special handling
required, such as cooling in
crushed ice (e.g., ammonia),
transportation at body temperature
(e.g., cold agglutinin), or light
protection (e.g., bilirubin)
15. Check the Site and Apply Bandage
● Site must be examined to verify
that bleeding has stopped.
● If bleeding persists beyond 5
minutes, notify the patient’s nurse
or physician.
● If bleeding has stopped and the
patient is an older child or adult,
apply a bandage and advise the
patient to keep it in place for at
least 15 minutes.
● Caution: Do not apply bandages to
infants and children under 2 years
of age because they pose a
choking hazard.
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG
16. Dispose of Used and Contaminated
Materials
● Wrappers and packaging are
discarded in regular trash
● Sharps must be disposed in
sharp-proof containers
17. Thank Patient, Remove Gloves, and
Sanitize Hands
● Be professional and courteous
● Gloves must be removed in an
aseptic manner and hand washed
or decontaminated with hand
sanitizer
18. Transport Specimen to the Lab
● Prompt delivery to the lab protects
specimen integrity and is typically
achieved by personal delivery,
transportation via a pneumatic
tube system, or a courier service
●
●
●
Fun fact: baby bottles are not allowed
inside the hospital
Unfilled or incompletely filled circles can
result in the inability to perform all
required tests.
Circles must be filled from one side of the
paper only and by one large drop that
spreads throughout the circle. Application
of multiple drops or filling circles from both
sides of the paper causes layering of
blood and possible misinterpretation of
results.
E. NEWBORN SCREENING
●
●
●
●
Mandated testing of newborns for the presence
of certain genetic (inherited), metabolic
(chemical changes within living cells),
hormonal, and functional disorders that can
cause severe mental handicaps or other
serious abnormalities if not detected and
treated early
Typically performed on a few drops of blood
obtained by heel puncture
The blood drops are collected by absorption
onto circles printed on a special type of filter
paper that is typically part of the NBS form
NBS Form contains the information of mother,
physician, and the baby (time of birth, date of
birth, mode of food source)
EXAMPLES OF DISORDERS TESTED
DURING NEWBORN SCREENING
●
●
●
●
●
PHENYLKETONURIA
○ Genetic disorder characterized by
a defect in the enzyme that breaks
down
the
amino
acid
phenylalanine, which is in almost
all food
HYPOTHYROIDISM
○ insufficient
levels
of thyroid
hormone
GALACTOSEMIA
○ Lack of enzyme to convert
galactose into glucose
CYSTIC FIBROSIS
○ Mutations in the gene that directs
a protein responsible for regulating
the transport of chloride across cell
membranes
Recommended Newborn Screening Tests
by Category (found on the next page)
SAN PEDRO COLLEGE – MAIN CAMPUS
BACHELOR OF SCIENCE IN MEDICAL LABORATORY SCIENCE
PRINCIPLES OF MEDICAL LABORATORY SCIENCE (LEC)
LECTURER: MS. DONAMIE PUTONG