health

1. BLOOD
COLLECTION

2. Introduction
 Blood is the body fluid used most frequently for
analytical purposes.
 Blood must be collected with care and adequate
safety precautions to ensure test results are reliable,
contamination of the sample is avoided and infection
from blood transmissible pathogens is prevented.
 The proper collection and reliable processing of blood
specimens is a vital part of the laboratory diagnostic
process in hematology as well as other laboratory
disciplines.

3. Introduction
 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 and wear
gloves.
 Care must be taken when handling especially, syringes and needles as
needle-stick injuries are the most commonly encountered accidents.
 Do not recap used needles by hand. Should a needle-stick injury
occur, immediately remove gloves and vigorously squeeze the wound
while flushing the bleeding with running tap water and then
thoroughly scrub the wound with cotton balls soaked in 0.1%
hypochlorite solution.
 Used disposable syringes and needles and other sharp items such as
lancets must be placed in puncture-resistant container for subsequent
decontamination or disposal.

4. Blood Collection
 Three general procedures for obtaining blood are (1) Venipuncture,
(2) Skin puncture, and (3) arterial puncture.
 The technique used to obtain the blood specimen is critical in order to
maintain its integrity. Even so, arterial and venous blood differs in
important respects.
 Arterial blood is essentially uniform in composition throughout the
body. The composition of venous blood varies and is dependent on
metabolic activity of the perfused organ or tissue.
 Site of collection can affect the venous composition. Venous blood is
oxygen deficient relative to arterial blood, but also differs in pH,
carbon dioxide concentration, and packed cell volume.
 Blood obtained by skin puncture is an admixture of blood from
arterioles, venules, and capillaries. Increased pressure in the arterioles
yields a specimen enriched in arterial blood. Skin puncture blood also
contains interstitial and intracellular fluids.

5. Venipuncture
 Venipuncture or phlebotomy: is a procedure done
to have an access to a vein (Blood collection, IV).
• There are three veins most commonly used in
venipuncture, or phlebotomy:
• The cephalic
• The median cubital
• The basilic veins
• These three veins are found in the
antecubital area.
Common Sites for
Venipuncture

6. The median cubital vein is the preferred vein for
phlebotomy because:
• It is usually larger than the other veins.
• Best anchored vein (More stationary(.
 Median Cubital – First Choice
• Well anchored vein, usually large and prominent.
• Very few problems. Offering the best chance for a close to painless puncture,
as there are few nerve endings close to this vein.
 Cephalic Vein – Second Choice: The cephalic vein may lie
close to the surface.
 Basilic Vein – Third Choice
• In many patients this vein may not be well anchored and will roll, making it
difficult to access with the needle.
• Additionally, this area is often more sensitive, thus a stick is slightly more
painful for the patient

7. Hand Veins
• At times, none of the veins of the antecubital fossa will be felt or
not be able to be used due to intravenous placement or injury,
hand veins may be used.
• Veins of the hand and wrist are usually close to the surface, but
they are prone to movement and rolling.
• Using these veins tends to be more painful for the patient, since
there are nerves running through the hand as well.
• If using these veins, it is important to anchor the vein with your
hand, holding it in place, when you are drawing the blood.

8. Venipuncture, why?
• Intravenous therapy
• Venous blood sample
• Treatment of certain diseases (hemochromatosis)
• Parenteral nutrition

9. Perform the Venipuncture process including
• Proper patient identification procedures.
• Proper equipment selection and use.
• Proper labeling procedures and completion
of laboratory requisitions.
• Preferred venous access sites, and factors to
consider in site selection, and ability to
differentiate between the feel of a vein,
tendon and artery.
• Patient care following completion of
venipucture.
• Safety and infection control procedures.

10. Venipuncture Procedure
1. Identify the patient.
2. Check the requisition form for requested tests, patient
information, and any special requirements.
3. Select a suitable site for venipuncture.
4. Prepare the equipment, the patient and the puncture site.
5. Perform the venipucture.
6. Collect the sample in the appropriate container.
7. Recognize complications associated with the phlebotomy
procedure.
8. Assess the need for sample recollection and/or rejection.
9. Label the collection tubes at the bedside or drawing area.
10. Promptly send the specimens with the requisition to the
laboratory

11. Order form / Requisition
Type of fluid

12. Labeling the Sample
• Patient's name, first and middle.
• Patient's ID number.
 NOTE: Both of the above MUST match the same
on the requisition form.
• Date, time and initials of the phlebotomist must be
on the label of EACH tube.

13. Equipment
• Needles (Smaller gauge numbers indicate larger
outer diameters.)
• Syringes
• Cotton
• Alcohol
• Tourniquet
• Collection tubes
• Adhesive bandages
• Gloves
• Sharp box

15. Needle and Syringes Components
Butterfly Needle

16. Procedural Issues
• Proper patient identification is MANDATORY match
with that on the request form
• Ask for a full name
• An outpatient must provide identification other than
the verbal statement of a name.
• Speak with the patient during the process

17. Venipucture Site Selection
• Median cubital then cephalic veins of the arm are used
most frequently
 Avoid
• Extensive scars from burns and surgery
• Hematom.
• Intravenous therapy (IV) / blood transfusions
 Turn off the IV for at least 2 minutes before
venipuncture.
 Apply the tourniquet below the IV site. Select a vein
other than the one with the IV.
 Perform the venipuncture. Draw 5 ml of blood and
discard before drawing the specimen tubes for testing.

18. Procedure for Vein Selection
• Palpate and trace the path of veins with the index
finger. Arteries pulsate, are most elastic, and have a
thick wall.
• If superficial veins are not readily apparent, you can
force blood into the vein by massaging the arm from
wrist to elbow, tap the site with index and second
finger, apply a warm, damp washcloth to the site for 5
minutes. Median basalic
Median Cephalic
Cephalic vein

19. Performance of a Venipucture
• Position the patient. The patient should either sit in a chair, lie
down or sit up in bed.
• Apply the tourniquet 3-4 inches above the selected puncture
site. Do not place too tightly or leave on more than 2 minutes.
• The patient should make a fist without pumping the hand.
• Select the venipuncture site.
• Prepare the patient's arm using an alcohol prep.
• Cleanse in a circular fashion, beginning at the site and working
outward.
• Allow to air dry.
• Grasp the patient's arm firmly using your thumb to draw the
skin taut and anchor the vein. The needle should form a 15 to
30 degree angle with the surface of the arm. Swiftly insert the
needle through the skin and into the lumen of the vein. Avoid
trauma and excessive probing.

21. The needle bevel up

23. Venipuncture Procedure after Tracing the Vein
• When the blood is drawn is , remove the tourniquet.
• Remove the needle from the patient's arm using a
swift backward motion.
• Press down on the gauze once the needle is out of the
arm, applying adequate pressure to avoid formation
of a hematoma.
• Dispose of contaminated materials/supplies in
designated containers.
• Mix and label all appropriate tubes at the patient
bedside.
• Deliver specimens promptly to the laboratory.

24. Blood won’ t flow
• If you do not see blood flow, the tip of the needle:
 May not yet be within the vein.
 May have already passed through the vein.
 May have missed the vein entirely.
 May be pushed up against the inside wall of the vein.

25. If An Incomplete Collection Or No Blood Is Obtained
Move forward Move backward
A hematoma forms under the
skin adjacent to the puncture
site - release the tourniquet
immediately and withdraw the
needle. Apply firm pressure.
Adjust the angle Withdraw and pressure for
5 min
Loosen the tourniquet

26. Collection Tubes
• The most common means of collecting blood
specimens is through the use of an evacuated tube
system.
• The system includes an evacuated tube, which can be
either plastic or glass; a needle; and an adapter that is
used to secure the needle and the tube.
• When the needle is inserted into a vein and a tube is
inserted into the holder, the back of the needle pierces
the stopper, allowing the vacuum pressure in the tube
to automatically draw blood into the tube

27. Collection Tubes
• For safety, OSHA recommends the use of plastic
tubes whenever possible.
• Most glass tubes are coated with silicone to help
decrease the possibility of hemolysis and to prevent
blood from adhering to the sides of the tube.
• Evacuated tubes are available in various sizes and
may contain a variety of premeasured additives.
• Manufacturers of evacuated tubes in the United States
follow a universal color code in which the stopper
color indicates the type of additive contained in the
tube.

28. Collection Tubes

29. Collection Tubes

30. Collection Tubes

31. Order of Draw in Vacutainer Tubes
• Blood culture studies tube (yellow stopper)
• Coagulation studies tube (light blue stopper)
• Serum tube with or without activator (red, gold, red-
gray marbled, orange, or yellow-gray stopper)
• Heparin tube (green or light green stopper)
• EDTA tube (lavender or pink stopper)
• Sodium fluoride with or without EDTA or oxalate
(gray stopper)

32. Skin Puncture
• Capillary blood (peripheral blood / microblood
samples) is frequently used when only small
quantities of blood are required, e.g., for hemoglobin
quantitation, for WBC and RBC counts and for blood
smear preparation.
• It is 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 and in
patients whose arm veins are being used for
intravenous medication.

33. Performance of a fingerstick
• The best locations for fingersticks are the 3rd (middle)
and 4th (ring) fingers of the non-dominant hand.
• Do not use the tip of the finger or the center of the
finger.
• Avoid the side of the finger where there is less soft
tissue, where vessels and nerves are located, and
where the bone is closer to the surface.
• The 2nd (index) finger tends to have thicker, callused
skin.
• The fifth finger tends to have less soft tissue overlying
the bone.
• Avoid puncturing a finger that is cold or cyanotic,
swollen, scarred, or covered with a rash.

35. • Using a sterile lancet, make a skin puncture just off
the center of the finger pad.
• The puncture should be made perpendicular to the
ridges of the fingerprint so that the drop of blood does
not run down the ridges.
• Wipe away the first drop of blood, which tends to
contain excess tissue fluid.
• Collect drops of blood into the collection device by
gently massaging the finger.
• Avoid excessive pressure that may squeeze tissue
fluid into the drop of blood.

36. Blood Collection on Babies
• Prewarming the infant's heel is important.
• Clean the site to be punctured with an alcohol sponge.
Dry the cleaned area with a dry cotton sponge.
• Hold the baby's foot firmly to avoid sudden
movement.
• Do not use the central portion of the heel because
• you might injure the underlying bone, which is close
to the skin surface.

37. • Do not use a previous puncture site.
• Make the cut across the heel print lines so that a drop
of blood can well up and not run down along the
lines.
• The recommended location for blood collection on a newborn
baby or infant is the heel.
• The diagram below indicates in green the proper area to use
for heel punctures for blood collection:

39. To prevent a hematoma
• Puncture only the uppermost wall of the vein.
• Remove the tourniquet before removing the needle.
• Use the major superficial veins.
• Make sure the needle fully penetrates the upper most
wall of the vein. (Partial penetration may allow blood
to leak into the soft tissue surrounding the vein by
way of the needle bevel).
• Apply pressure to the venipucture site.

40. To prevent hemolysis
• Mix tubes with anticoagulant additives gently 5-10
times.
• Avoid drawing blood from a hematoma.
• Avoid drawing the plunger back too forcefully, if
using a needle and syringe.
• Make sure the venipucture site is dry.
• Avoid a probing, traumatic venipuncture.

41. Hemoconcentration
• An increased concentration of larger molecules and
formed elements in the blood may be due to several
factors:
 Prolonged tourniquet application (no more than 2 minutes).
 Massaging, squeezing, or probing a site.
 Long-term IV therapy.

42. Anticoagulants used in Blood Preservation
• Anticoagulants are chemical substances that are
added to blood to prevent coagulation.
• In other words, certain steps are involved in blood
coagulation, but if one of the factors is removed or
inactivated, the coagulation reaction will not take
place.
• The substances responsible for this removal or
inactivation are called anticoagulants.
• While clotted blood is desirable for certain laboratory
investigations, most hematology procedures require
an anticoagulated whole blood.

43. Anticoagulants
• The blood is withdrawn from the patient, it is mixed
with an anticoagulant to prevent coagulation.
• The three most commonly used anticoagulants in the
hematology laboratory are discussed below:
1- EDTA:
• Is generally available as the sodium, dipotassium or
tripotassium salt of ethylene diamine tetra acetic acid. It
is used in concentration of (1.5±.25).
• EDTA prevents coagulation by binding the calcium in
the blood (calcium is required for blood coagulation).

44. Excessive concentration of EDTA cause:
• Shrinkage of the red blood cells leading to decreased
hematocrit increased MCHC, falsely low ESR.
• Degenerative changes in the white cells and the
platelets will swill and break up causing a falsely
increased in platelet counts.

45. 2- Sodium citrate:
• Used for coagulation studies in a concentration of 1
part 0.109M sodium citrate (tri sodium citrate
dehydrate) to 9 part whole blood.
• Sodium citrate prevents coagulation by binding the
calcium of the blood in a soluble complex.
3- Heparin:
• May be used in concentration of 15 to 30 units/ml of
whole blood. its may cause clumping of platelets and
white cells.
• Coagulation is prevented by interaction with anti
thrombin III and subsequent inhibition of thrombin.

46. 4- Double Oxalate:
• Salts of oxalic acid by virtue of their ability to bind and
precipitate calcium as calcium oxalate serve as suitable
anticoagulants for many hematologic investigations.
• Three parts of ammonium oxalate is balanced with two
parts of potassium oxalate (neither salt is suitable by
itself, i.e., ammonium oxalate causes cellular swelling
and potassium oxalate causes erythrocyte shrinkage).
• It is used in the proportion of 1-2mg/ml of blood.

47. Fainting; what to do?

48. Fainting; what to do?