Chapter 3 Basic Hematological tests..pdf

CHAPTER 3
3. Basic Hematological tests
3. Basic Hematological tests

Objectives
Upon completion of this chapter the student will be able to:
 List the safety precautions that should be taken and
observed in blood collection
 Identify the tests that are done on capillary blood
 Indicate the anatomical sites of capillary blood collection
 Perform the procedure of capillary blood collection by
 Perform the procedure of capillary blood collection by
skin puncture
 List the advantages and disadvantages of capillary
blood sample
 Distinguish the laboratory tests for which venous blood is
required

Objectives cont’d
 Indicate the anatomical sites of venous blood collection
 Perform venous blood collection
 List the advantages and disadvantages of venous blood
sample
 Explain the difference between capillary and venous
blood
blood
 Explain complications of venous blood sample collection
 Describe arterial blood collection
 List the advantages of the vacutainer method of venous
blood collection over the syringe method
 Identify the watch word in preventing hemolysis in a
sample of blood
 Exercise ethical handling of patients

3.1. Introduction to sample collection
 Hematology is the branch of medicine concerning the
study of blood, the blood-forming organs, and blood
diseases
 Hematology tests include laboratory assessments of blood
 Hematology tests include laboratory assessments of blood
formation and blood disorders
 Proper collection and reliable processing of blood
specimens is a vital part of the laboratory diagnostic
process in hematology laboratory

Cont,,,
 Blood must be collected with care and adequate safety
precautions to ensure:
 test results are reliable
 contamination of the test sample is avoided and
 infection from the blood transmissible pathogens is
prevented

Cont,,,
 All material of human origin should be regarded as
potentially infectious
 When collecting blood sample, the operator should wear
disposable rubber gloves
 The operator is also strongly advised to cover any cuts,
abrasions or skin breaks on the hand with adhesive tape
before wearing gloves

Cont,,,
 Care must be taken when handling syringes and needles
 Do not recap used needles by hand
 needle-stick injuries are the most commonly
encountered accidents
 Should a needle-stick injury occur:
 immediately remove gloves
vigorously squeeze the wound while flushing the
 vigorously squeeze the wound while flushing the
bleeding with running tap water
 thoroughly scrub the wound with cotton balls soaked in
0.1% hypochlorite solution
 Report to supervisor immediately
 Adhere to national guideline on HIV exposure risk
regarding post exposure prophylaxis (PEP)

Cont,,,
 Used disposable syringes , needles, other sharp items
such as lancets must be placed in puncture-resistant
container for subsequent decontamination or disposal

3.2. Capillary blood collection
 Also referred to as microblood samples
collection/dermal puncture
 Is collecting blood after an incision is made
to the skin with a lancet
 Preferred when only small quantities of
blood are required
 e.g., for hemoglobin quantitation, for WBC
and RBC counts and for blood smear
preparation

Cont,,,
 Also used when venipuncture is impractical, e.g.,
 In infants
 In cases of severe burns
 In extreme obesity where locating the veins could be
a problem
 In patient whose arm veins are being used for
intravenous medication

Cont,,,
 Sites of Puncture
 Adults and children:
 Palmer surface of the tip of the ring or middle
finger or free margin of the ear lobe
 Infants: plantar surface of the big toe or the heel

Cont,,,
 The areas of the foot of a baby or infant
that are suitable for obtaining capillary
blood

Cont,,,
 Considerations:
 Edematous, congested and cyanotic sites should not be
punctured
 Cold sites should not be punctured as samples collected
 Cold sites should not be punctured as samples collected
from cold sites give falsely high results of hemoglobin
and cell counts
 Site should be massaged until it is warm

3.2.1. Capillary sample collection method
 Materials Required
 Cotton or gauze pads
 70% alcohol or other skin
antiseptic
 sterile disposable lancet
(Automatic lancet)

Cont,,,
Technique:
1. Rub the site vigorously with cotton or a gauze pad
moistened with 70% alcohol
 to remove dirt and epithelial debris and
 to increase blood circulation in the area
 If the heel is to be punctured, it should first be warmed by
immersion in a warm water or applying a hot towel
compress. Otherwise values significantly higher than
those in venous blood may be obtained.

Cont,,,
2. After the skin has dried, make a puncture 2-3mm
deep with a sterile lancet
 A rapid and firm puncture should be made with
control of the depth
 A deep puncture is no more painful than a
superficial one and makes repeated punctures
unnecessary.

Cont,,,
 The first drop of blood which contains tissue juices
should be wiped away
 The site should not be squeezed or pressed to get
blood since this dilutes it with fluid from the tissues.
 a freely flowing blood should be taken or a
moderate pressure some distance above the
puncture site is allowable

Cont,,,
3. Stop the blood flow by applying slight pressure at the site
preferably with a gauze pad
 Cotton balls are not recommended, because they
stick to the site and can initiate bleeding
 Advantages of Capillary Blood
 obtained with ease
 the preferred specimen for making peripheral blood films
since no anticoagulant is added that may affect cell
morphology

Cont,,,
 Disadvantages of Capillary Blood
 only small amounts of blood can be obtained and
repeated examinations require a new specimen
 Platelet count cannot be performed on capillary blood
 some platelets are unavoidably lost by adherence
onto the wound
onto the wound
 Precision is poorer in capillary than venous blood
 because of variation in blood flow and dilution with
interstitial fluid
 Blood in microtubes frequently hemolyse
 hemolysis interferes with most laboratory tests

3.3. Venous Blood Collection
 Collection of blood from the vein (venipuncture)
 Also referred to as phlebotomy
 Necessary for most tests that require anticoagulation or
larger quantities of blood, plasma or serum.
 Sites of Puncture
 Veins of the forearm are preferred; wrist or ankle can
 Veins of the forearm are preferred; wrist or ankle can
also be used
 veins in the antecubital fossa of the arm are the
preferred sites
 they are larger than those in the wrist or ankle
regions
 hence are easily located and palpated in most
people

The three main veins in the forearm
1. Medial Cubital
 First choice well
anchored and easy to
penetrate
2. Cephalic
 On the outside surface
 On the outside surface
 Well anchored
3. Basilic
 Not well anchored, tends
to roll, painful and can
cause nerve damage
Anterior surface of the left arm showing
veins most suitable for venepuncture.

Cont,,,
Venous blood collection in infants and
children
 presents special problems
 small size of the veins
 difficulty in controlling the patient; needs excellent
interpersonal skill
interpersonal skill
 Require experience
 Areas also used for obtaining blood
 external jugular vein in the neck region
 femoral vein in the inguinal

Cont,,,
 Materials:
 Gloves
 vacutainer tube
 vacutainer tube holder and Two-way needle
 sterile syringe and needle (if the syringe method is
used)
used)
 tourniquet
 gauze pads or cotton,
 70% alcohol or suitable skin antiseptic
 test tubes with or without anticoagulant (for syringe
method)
 Sharp container
 Band Aid (to stop further bleeding)

Vacutainer Tubes color
codes??
Vacutainer tube holder

Needles
 Sterile, Disposal and for
Single use only
 Color coded for size or
 Color coded for size or
gauge
 Hollow stainless steel shafts
 Bevel or slant at the end

Needle Features
 Bevel or slant:
 Must face up
 Shaft:
 cylindrical portion, length
ranges from .65 to 3.80 cm
ranges from .65 to 3.80 cm
 Hub:
 attaches the needle to the
holder
 Gauge:
 The size of the needle, refers
to the diameter of the needle

Needle
 Needle Size or Gauge
depends on the size and
depth of the vein to be
punctured
 Gauge is the diameter of the
needle
 The larger the gauge number
 The larger the gauge number
the smaller the needle
 Range from 16 – 25
 Routine: 21 gauge
 Children: 23 gauge
 Most common used 21g by
3.80 cm
 Colored coded for size

Multi Sample Needle
 Used for multiple samples
during a single
venipuncture
 Composed of a double
pointed needle
pointed needle
 The hub screws into the
needle holder
 Open with a twist motion

Safety Needles
 Allows the user’s hand to
remain behind the needle
 Always use a safety
needle when available
needle when available
 Minimizing exposure to
blood borne pathogens

Tourniquet
 Slow down venous flow
without affecting arterial
flow
 To enlarge the vein for
easier location and easier
easier location and easier
penetration
 To assess the width,
direction and depth of
veins
 Should be left on for no
longer than one minute

Gloves
 ‘Universal Precautions”
require the wearing of gloves
 Gloves provide protection
from infection
 A new pair of gloves must be
worn for each client and for
each new procedure
each new procedure
 Types: “A good fit is essential”
 Nitrile
 Vinyl
 Latex Free
Sharp container

3.3.1. Vacutainer technique of venous
blood collection
 Techniques
1. Assemble the necessary materials and equipment
thread the short end of the double-pointed needle into
2. thread the short end of the double-pointed needle into
the holder and push the tube forward until the top of the
stopper meets the guide mark on the holder

Cont,,,
Needle Holder and Adapter
 The second pointed
needle with rubber sleeve
resides in the holder
resides in the holder
 Push the tube directly into
the middle of the holder
for proper collection
 Second needle will
penetrate top of tube

Cont,,,
 The point of the needle will thus be
embedded in the stopper without
puncturing it and loosing the vacuum in
the tube.
the tube.
3. Identify the right patient and allow
him/her to sit comfortably preferably in
an armchair stretching his/her arm

Adult Venipuncture Procedure
Identify yourself
 Great your client
 Be friendly
 State your name
 State your purpose

Client Identification
 The most important step in specimen collection is client
identification
 Misidentification of a client can be grounds for dismissal
 When identifying a client, ask them to state his or her full
 When identifying a client, ask them to state his or her full
name
 NEVER SAY: “ARE YOU MRS SMITH?”

Client Identification
 Verbal: Spell their last name followed by their first
Make sure their name is spelt correctly
 Ask them to state their birth date or check an
identification number for a second form if identification
 Two forms of identification are needed

Inpatient or Ward Contact
 Before entering a patient’s room
 Always knock before entering
 Greet patient in a friendly manner
 Always make your presence know before proceeding
 Always make your presence know before proceeding
into the room and pulling back the curtain

Identifying Yourself
 State your name, where are from and the purpose of you
visit
 If a patient is sleeping, wake gently
 Speak softly
 Speak softly
 Never turn on a bright light
 Never attempt to draw blood from a sleeping patient

Unconscious Patient
 Identify yourself and inform the patient of your intent
 Ask caregiver to identify the patient
 Compare this information to the identification bracelet
 Continue to speak to the patient
 Continue to speak to the patient
 Ask for help in holding the patient because they can
sense pain but can not control their reactions

Doctors and Visitors
 If a doctor is with a patient, don’t interrupt but come back
latter
 If the blood work is needed immediately, excuse yourself
and explain why you are there
 If visitors are present, it is best to ask them to step out of
the room
 If a patient is not in the room, find out where they are or
notify the nurse in charge

Cont,,,
4. Reassure the patient
5. Apply the tourniquet
6. Prepare the arm by swabbing the antecubital fossa with
a gauze pad or cotton moistened with 70% alcohol

Cont,,,
Tourniquet Application
 Position the tourniquet 7.5
– 10 cm above the
venipuncture site with strip
venipuncture site with strip
equal on both sides
 Pull Left side over the
Right side and make an X

Tourniquet Application cont’d
 With X in place, tuck a loop
 Have both ends of strip facing
up
up
 End of the tourniquet that is
facing up is used for easy
removal

Cleaning the Arm
 Clean the arm using 70%
isopropyl alcohol
 Clean area in concentric
circles starting at site and
circles starting at site and
ending outside of site. Do
not re-touch the cleaned
area
 Let air dry

Cont,,,
7. Grasp the back of the patient’s arm at the elbow and
anchor the selected vein by drawing the skin slightly taut
over the vein
8. insert the needle properly into the vein;
 the index finger is placed along side of the hub of the
needle with the bevel facing up
 The needle should be pointing in the same direction
as the vein
9. Then the point of the needle is advanced 0.5-1.0cm into
the subcutaneous tissue (at an angle of 450) and is
pushed forward at a lesser angle to pierce the vein wall

Cont,,,
10. When the needle is properly in the vein, the vacuum tube
is pushed into the needle holder all the way so that the
blood flows into the tube under vacuum
11. The tourniquet should be released the moment blood
starts entering the vacuum tube
 otherwise, some hemoconcentration will develop after
 otherwise, some hemoconcentration will develop after
one minute of venous stasis
12. After drawing the required blood sample, apply a ball of
cotton to the puncture site and gently withdraw the needle.
13. Instruct the patient to press on the cotton

Cont,,,
14. Remove the tube from the vacutainer holder and if the
tube is with anticoagulant, gently invert several times
 Invert 8-10 times for EDTA tube
15. Label the tubes with patient’s name, hospital number
and other information required by the hospital (before
the patient leaves the collection area)
the patient leaves the collection area)
16. Re-inspect the venipuncture site to ascertain that the
bleeding has stopped
17. Do not let the patient go until the bleeding stops
 If bleeding does not stop apply band aid
18. Bid farewell to the patient with smile

Inverting and Mixing the Tubes
 Tubes with additives must
be gently mixed
 Gently invert several
times for proper mixing

Cont,,,
1 2
1. Venepuncture technique using an evacuated container; the
distal end of the needle has been screwed into the holder and
the proximal needle has then been unsheathed and inserted
into a suitable vein.
2. Venepuncture technique using an evacuated container; the
evacuated container has been inserted into the holder and
forced onto the sharp end of the needle.

Anticoagulants
 EDTA
ethylenediaminetetraacetic
acid in a tripotassium or
disodium base (Purple):
prevents clotting by binding
prevents clotting by binding
Ca.
 Used in hematology or TBC
and CD4

Anticoagulants
 Sodium Citrate (Light
Blue): prevents clotting by
binding the calcium.
 Used for coagulation
 Used for coagulation
workup (PT and APTT)

Anticoagulants
 Heparin (Green): Three
types: ammonium, lithium,
and sodium. Prevents
clotting by inhibiting
clotting by inhibiting
thrombin. Used for plasma
chemistry testing
 Use appropriate type of
heparin

Anticoagulant/Additive
 ANTICOAGULANT
 Potassium or ammonium
oxalate (Gray): prevents
clotting by binding the
calcium. Used in glucose
calcium. Used in glucose
testing
ADDITIVE
 Sodium Fluoride (Gray):
inhibits the metabolism of
glucose by the cells. Used
for glucose tolerance
testing

Additives
 Clot activator:
 initiate or enhance
coagulation. Can be
thrombin, glass or silica
particles
particles
 Gel Separator:
 forms a barrier between the
cells and the serum portion
after the blood has been
spun
 Used for Chemistry
Testing

Tube Stoppers
 Red/Glass: no additives
 Red/Plastic: clot activator
 Red/Gray or marbled: gel separator
 Green: Heparin (three types)
 Mint Green: Heparin with gel separator
 Lavender: EDTA
 Light Blue: Sodium citrate
 Gray: potassium oxalate and sodium fluoride
 Hemogard: plastic stopper with rubber inside.
Used for safety

Order of Draw with the
Evacuated Tube System
 Blood Cultures: sterile specimen
 Light Blue: sodium citrate for coagulation. Tube should
be full and well mixed
 Gel Separator with or without clot activator
 Gel Separator with or without clot activator
Glass or Plastic Tubes
 Green: heparin or plasma chemistry
 Purple: EDTA for Hematology, CBC, CD4
 Gray: oxalate/fluoride, glucose testing

Recommended order for taking blood
samples.
Blood culture tubes
Plain glass tubes for serum samples
Sodium citrate tubes
Sodium citrate tubes
Gel separator tubes/plain plastic tubes for serum
Heparin tubes/heparin gel separator tubes
EDTA tubes
Fluoride tubes for glucose
EDTA= ethylenediaminetetra-acetic acid.

Advantages of the Vacutainer Method of Venous
Blood Collection:
 an ideal means of collecting multiple samples with ease
 eliminates many of the factors that cause hemolysis.
 no preparation of anticoagulants and containers needed.
 One can choose among a wide range of tube size with or
with out anticoagulant.
with out anticoagulant.
 Because the evacuated tubes are sterile, avoids
possible bacterial contamination
 Thus, an ideal blood sample for microbiological
analysis

3.3.2. Syringe method of blood
collection
 Remove the syringe from its protective wrapper and the
needle from the cap
 assemble them allowing the cap to remain covering the
needle until use.
 Attach the needle so that the bevel faces in the same
 Attach the needle so that the bevel faces in the same
direction as the graduation mark on the syringe
 Check to make sure:
 the needle is sharp
 the syringe moves smoothly
 there is no air left in the barrel

Syringe method cont’d
 Identify the right patient and allow him/her to sit
comfortably preferably in an armchair stretching his/her
arm.
 Reassure the patient
 Apply the tourniquet
 Prepare the arm by swabbing the antecubital fossa with
 Prepare the arm by swabbing the antecubital fossa with
a gauze pad or cotton moistened with 70% alcohol.
 Grasp the back of the patient’s arm at the elbow and
anchor the selected vein by drawing the skin slightly taut
over the vein

Syringe method cont’d
 Using the assembled syringe and needle, enter the skin
first and then the vein
 insert the needle properly into the vein;
 the index finger is placed along side of the hub of the
as the vein.
 The plunger is drown back to create suction pressure to
draw the blood

Venepuncture technique using
needle and syringe

Advantages of Venous Blood:
 various tests to be repeated in case of accident or
breakage
 checking of a doubtful result
 performance of additional tests
 aliquots of the specimen (plasma and serum) may be
 aliquots of the specimen (plasma and serum) may be
frozen for future reference.
 reduces the possibility of errors resulting from
 tissue dilution with interstitial fluid
 constriction of skin vessels by cold that may occur in
taking blood by skin puncture.

Disadvantages of Venous Blood:
 lengthy procedure
 technically difficult in children, obese individuals and in
patients in shock.
patients in shock.
 more likelihood of occurrence of Hemolysis
 hemolysis must be prevented because it leads to lowered red
cell counts and interferes with many chemical tests.
 Hematoma (or blood clot formation inside or outside the
veins) may also occur

Difference Between capillary and Venous
Blood:
 Higher values in peripheral blood than in venous blood
for
 PCV
 RBC
 Hgb
WBC
 WBC
 Neutro
 Mono (by about 12%)
 Higher values in venous than peripheral blood for
 Platelet (by about 9%); may be due to adhesion of
platelets to the site of the skin puncture.

3.4. Arterial blood collection
 An ideal specimen for many analyses because its
composition is consistent throughout the body whereas
venous blood varies relative to the metabolic needs of the
areas of the body it serves
 Not used for routine tests
 More invasive
 Technically difficult

 Lots of pre-analytical interferences:
 Exposure to air before testing
 Delay in transport
 Requires proper specimen collection
 E.g. In patients with metabolic diseases, it is
difficult to differentiate whether it is venous or
arterial origin
arterial origin
 Never select a site in a limb within A-V shunt or
fistula
 Primarily for evaluation of arterial blood gases (ABGs)
 For the diagnosis and management of respiratory
diseases

Prevention of Hemolysis
 Use syringe, needle and test tubes that are dry and free
from detergent
 traces of water or detergent cause hemolysis
 Use smooth and good quality sharp needles
 Avoid rough handling of blood at any stage
 Avoid rough handling of blood at any stage
 Do NOT eject the blood from the syringe through the
needle as this may cause mechanical destruction of
the cells
 Transfer the blood from the syringe by gently ejecting
down the side of the tube
 Mix blood with anticoagulant by gentle inversion not
by shaking

Prevention of Hemolysis cont’d
 Tourniquet should NOT be too tight and should be
released before blood is aspirated
 If examination is to be delayed beyond 1-3 hrs, do not
allow the sample to stand unplugged or at room
temperature.
 Apply stopper and store in a refrigerator at 40C
overnight

Prevention of Hemolysis cont’d
 Blood should NOT be stored in a freezer because the red
cells will hemolyse on thawing
 Make sure that all solutions with which blood is to be
mixed or diluted are correctly prepared and are isotonic
 Hypotonic solutions will lead to hemolysis.
 When obtaining blood by skin puncture:
 Make sure the skin is dry before pricking
 Use sharp, 2-3mm lancets that produce clean puncture
wounds
 Allow the blood to flow freely

Inpatient or Ward Identification
 Emergency Room patients:
 should have a identification band on, can be asked
directly if conscious or put a temporary band on
 Always make sure all information matches
 Always make sure all information matches
 Young children:
 confirmed by parents or relatives
 Two identifiers are needed for any person that is to be
drawn

Cont’d
 It is very important for healthcare professional to ensure
that specimens are drawn from the correct patient
 Ask the patient to state his/her full name, birth date or
identification number
 Compare the information given with the information on
the patient’s identification bracelet
 Report any error before drawing the patient

Cont’d
 Any discrepancy between ID band and request slips
should be verified
 ID bracelet missing on wrist, check ankle
 If band is not on patient but on the wall, bed or night
 If band is not on patient but on the wall, bed or night
table the patient Can Not be Drawn
 A new band must be issued and placed on the patient

Bed Side Manner
 Gain the client’s or patient’s trust and confidence
 Put the client/patient at ease
 Use a cheerful and pleasant manner
A phlebotomist who has a professional appearance and
 A phlebotomist who has a professional appearance and
behaves in a professional manner will convey confidence
to the client

Handling Difficult Clients
 Remain calm and professional
 Treat the client in a caring manner under any
circumstances
 Never force a client to do anything that they do not want
 Never force a client to do anything that they do not want
to do

Test Request Form
 Lists the information
needed for collection
 Includes:
 Client’s complete name
 Client’s complete name
 Client’s date of birth/age
 Date and Time specimen is
to be drawn
 Types of tests
 Physician name

Explain the Procedure
 Some clients may have had their blood drawn for testing
 State to the client “I’m going to draw some blood from
you today.”
 Serves two purposes:
 Serves two purposes:
 client aware of what is to happen and gives you
consent to proceed

Client Inquiry About Tests
 Most often asked question is
“What are these tests for?”
 If you do not feel comfortable about the question, refer
them to their doctor
them to their doctor
 If the tests are routine and non threatening you can
explain “ a kidney function test”
 All test results are given to the doctor

If the Client Objects
 The client has the right to refuse
 Never force a client
 You may try to convince them how important the
procedure is
procedure is
 Ask for assistance

Assemble Equipment
Requires:
 Gloves
 Tourniquet
 Alcohol Pad
 Alcohol Pad
 Gauze Pad
 Appropriate Tubes
 Needle and Holder
 Band Aid

Wash Hands
 Proper hand washing
 Followed by glove application
 Always put a clean pair of gloves for each client and
each new procedure
each new procedure

Position Client
 Reassure the client
 Always have the arm in comfortable position for the
client and for you
 Have the arm in a downward position
 Have the arm in a downward position
 Client should be in a chair or lying down

Apply Tourniquet
 Applied to increase
pressure in the veins and
aid in site selection
 Applied 7.5 – 10 cm
 Applied 7.5 – 10 cm
above the intended site
 Should not be left on for
no longer than ONE
minute

Vein Selection
 Have client make a fist
 Use tip of index finger to
palpate the vein
 Determine size, depth and
 Determine size, depth and
direction
 A vein has a bounce to it

Veins Used for Phlebotomy
 Antecubital Region
 1st: Median Cubital
 2nd: Cephalic
 3rd: Basilic
 3rd: Basilic
 Volar Venous network
(hand)

Vein Selection
 1st choice
 Median Cubical
 2nd choice
 Cephalic
 3rd choice
 Basilic

Cleanse Site
 70% isopropyl alcohol
 Clean site using a circular motion starting from the
center moving outward
 Let alcohol dry or dry site
 Let alcohol dry or dry site
 DO NOT TOUCH THE SITE AFTER IT HAS BEEN
CLEANED

Anchor the Vein
 Use thumb to pull vein taut
but not tight
 This helps the vein not to
move or roll
 Pick up needle and
 Pick up needle and
visually inspect
 Needle should be bevel
side up
 Insert needle at a 15 to 30
degree angle using a
quick smooth motion

Fill Tubes
 As soon as blood appears
in the tube the tourniquet
is to be released
 When changing tubes
hold the needle and
hold the needle and
holder in correct position
 Hold Steady
 Follow order of draw
 Mix all tubes with
additives

Withdraw Needle
 After last tube is full remove the tube from the holder
 Remove needle in one quick motion
 Have gauze ready to apply pressure.
Apply pressure to the arm. Hold in a straight position.
 Apply pressure to the arm. Hold in a straight position.
DO NOT HAVE THE client BEND HIS ARM UP
 Make sure tourniquet is removed before last tube is
filled

Needle Disposal
 Needle disposal is done
immediately after the draw
 Dispose needle in a
Biohazard SHARPS
container
container
 Needle and holder are
disposed of together
 Do Not Re-Use Needles
or holders
 They are for single use
only

Specimen Labeling
 Label all tubes after
blood is in them
 Should contain:
 Client’s full name
 ID number
 Time of collection
 Date
 Phlebotomist initials

Last Steps
 Check clients arm and
apply band aid
 Dispose of contaminated
materials
materials
 Thank client
 Remove gloves and Wash
hands

Failure to Obtain Blood
 REMAIN CALM
 Check:
 Needle Position
Reposition
 Reposition
 Vacuum of the tube
 replace with a new tube
 Tube position
 Lift up or down

Needle Position
 Needle not deep
enough: slightly push
the needle back in
 Needle bevel against
vein wall: blood flow
will be impaired if the
bevel is not in the up
position

Needle Position
 Correct angle
 Needle too deep: Pull
back slightly

Needle Position
 Needle has slipped beside vein:
 Vein not anchored well, try to redirect slightly
Needle position can not be determined:
 Needle position can not be determined:
 Try to feel for the vein above or below the site of the
needle
 If you can feel the vein, again try to redirect

Needle position
 If you can’t feel the vein,
DO NOT PROBE BLINDLY, IT HURTS
 Remove the needle and begin again
A phlebotomist should only attempt twice to obtain the
 A phlebotomist should only attempt twice to obtain the
specimen

Collapsed Vein
 Sometimes the vacuum in
the tube will cause the
vein to disappear
 Reapply the tourniquet; it
 Reapply the tourniquet; it
may increase the flow into
the area
 If you still don’t feel the
vein, remove the needle
and begin again

Complications Associated
with Blood Collection
 SITE SELECTION
 Avoid scars and burns
 Mastectomy:
 Venipuncture should never be performed from the
 Venipuncture should never be performed from the
arm on the same side of the mastectomy
 Edema:
 Abnormal accumulation of fluid in the tissues. Lab
results will be inaccurate

 Hematoma: is a swelling or
mass of blood under the skin.
This area is usually sore and
painful.
 Leakage of a large amount of
fluid around the puncture site
fluid around the puncture site
and the area swell
 Apply enough pressure at the
venipuncture
- Should be avoided

 Obesity:
 Veins may be deep. The cephalic is the vein of
choice
 Damaged veins:
 Damaged veins:
 Feel hard and cord like, difficult to penetrate and
should be avoided

Complications Affecting the
Client
 Allergies:
 May have a reaction to the alcohol or band-aid
 Seizures:
 Remove the needle immediately
 Remove the needle immediately
 Hold pressure to the site without restriction of the
client’s movements
 Excessive Bleeding:
 Pressure should be maintained for more than 5
minutes

Client
 Fainting /syncope
 If there is history, lie the client down.
 If the client faints during the procedure, remove the
needle immediately.
needle immediately.
 Put the client’s head between their knees and make
them take deep breaths.
 Apply ammonia inhalation

Client
 Nausea:
 client should be made comfortable, deep breaths
 Infection:
 Rare occurrence, clean site properly and apply a
band-aid
 Pain:
 A little pain is associated with the procedure
 No blind probing
 Petechiae:
 Red spots under the skin which appear when a
tourniquet is left on.
 Usually there is capillary fragility

Complications cont’d
 Bruise/Echymoses caused by leakage of a small amount
of fluid around the tissue
 To prevent apply direct pressure to the venipuncture
site
site
 Do NOT advise patients to bend his arm at the elbow

Inadvertent Arterial Puncture
 Hold pressure for at least 5 minutes
 Arterial blood has a bright red color and the tube fills
very quickly
 The lab should be aware that it is arterial blood
 The lab should be aware that it is arterial blood
 Lab values are different

Collection Techniques
Affecting the Specimen
 Hemoconcentration:
 Prolonged application of the tourniquet, vigorous and
probing
 Hemolysis: results from the destruction of the red cells
 Hemolysis: results from the destruction of the red cells
 shaking the tube hard
 drawing from a hemtoma
 pulling on a syringe to quickly
 probing
 to small a needle
 forcing the blood into another tube

Collection Techniques Affecting
the Specimen
 Partially filled tubes:
 Filling additive tubes until the vacuum is exhausted is
important for proper ratio of anticoagulant to blood
 Very important for coagulation studies, under
 Very important for coagulation studies, under
filled tubes are not acceptable
 Specimen Contamination:
 Alcohol can cause contamination, touching the site,
not following order of draw

Safety Reminders
 Always use standard or universal blood precautions
when drawing blood
 Always wear gloves when drawing blood
 Identify patient by asking for a name or check armband
 Identify patient by asking for a name or check armband
 Do not allow tourniquet to remain on the arm for more
than one minute
 Properly label tubes after the blood is in them

Cont’d
 Patient identification is the most important step in blood
collection
 Wash hands and wear gloves for every patient
 Clean arm in concentric circles, let dry
 Clean arm in concentric circles, let dry
 Anchor vein with the thumb and enter the vein at a 15 –
30 degree angle
 Always follow order of draw

Chapter 3 Basic Hematological tests..pdf

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