POLICY:
A work instruction on how to perform Venipuncture to serve as
a guide to the Medical Technologists.
PURPOSE:
procedure.
To establish a documented work instruction for the Venipuncture
MATERIALS: Requisition form, gloves (nitrile), goggles and mask, laboratory gown,
phlebotomy collection tray, tourniquet, 70% isopropyl alcohol pad, 10 mL syringe and
21-gauge hypodermic needle, 21-gauge multidraw needle, vacuum tubes or special
collection tubes, vacuum tube adapter or holder, transfer devices, cotton balls, 2×2
gauze, adhesive bandage or micropore tape, antimicrobial hand gel, indelible pen,
sharps container and biohazard red bag, test tube rack, biohazard transport bag
(optional).
PRINCIPLE: Venipuncture describes the procedure of entering a vein with a needle
to obtain a sample of the circulating blood for hematological, biochemical, or
bacteriological laboratory testing as required by a physician. Venipuncture by syringe
— the venous blood collected is to be aliquoted into evacuated tubes and/or special
collection containers. Venipuncture by evacuated tube system — the amount of the
venous blood sample is dependent on the size of the tube and the test requirements.
PROCEDURES:
Venipuncture (Syringe and Evacuated Tube System)
1.
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9.
Assemble the supplies. Organizing supplies before the procedure ensures
a more timely and professional process.
Obtain and examine the requisition form.
Greet and reassure the patient and explain the procedure to be performed.
Help the patient into a comfortable position in a phlebotomy chair or bed.
Identify the patient verbally by asking the patient’s both first name and last
name. Verify it with the tests ordered and the computer label or
identification number. If a fasting specimen is required, the patient should
be verified from refraining food or drink consumption except water for 12
hours.
Wash hands and apply gloves, goggles, and mask.
Needle preparation:
A. Syringe
i. Open the sterile needle and sterile syringe packages. Check if the
syringe and needle is well-assembled by pulling the plunger
halfway out and pushing it all the way in again.
ii. Choose the right vacuum tubes for later transfer of the specimen.
B. Evacuated Tube System
i. Break the seal on the shorter needle; thread the shorter needle
into the holder/adapter. Select the first tube and gently place it into
the holder/adapter (do not puncture the tube yet).
All tubes with anticoagulants should be tapped and checked for expiration
dates. Place the tubes in the correct order in a holding rack.
Apply the tourniquet 3 to 4 inches above the antecubital fossa and select a
site. Pull it tight enough to trap venous blood without cutting off the arterial
flow.
Position the patient by slightly bending their arm and asking them to make
a fist. Patient must avoid a hand pumping action and hard tapping of the
veins is discouraged. The patient must not hyperextend the arm.
10. Select a vein by palpation. Note the location and direction of the vein.
Palpate the area in a vertical and horizontal direction to locate a large vein
and to determine the depth, direction, and size. To test the vein's elasticity
and rebound, place the index finger over it and lightly press, then release
the pressure.
11. Cleanse the site with 70% isopropyl alcohol alcohol swab in concentric
circles moving outward and allow it to air dry. Avoid touching the site after
cleansing.
12. Draw the skin taut with the thumb by placing it 1 to 2 inches below the
puncture site
13. With the bevel up, line up the needle with the direction of the vein and
perform the puncture. The point of the needle should enter the skin about
1⁄4 inch below where the vein was palpated. Do not move the needle from
side to side once the vein has been entered. Do not push down or pull up
the needle.
14. Proceeding venipuncture procedures:
A. Syringe
i.
Let go of the skin and use the other hand to pull back on the
plunger. Pull gently and only as fast as the syringe fills. If the vein
collapses, stop pulling on the plunger and let the vein refill.
ii. Have the patient open the hand when the syringe is full. Remove
the tourniquet.
iii. Lightly place a cotton ball above the puncture site and remove the
needle in the same direction as inserted.
iv. Apply pressure to the site for 2 to 3 minutes. Let the patient assist
by holding the pressure if desired. The patient can elevate the arm
but should be instructed not to bend the elbow.
v. Aliquot blood into the appropriate tubes in the rack in the proper
order. During transfer, hold each tube at the base only.
vi. Puncture the vacuum tube through the rubber stopper with the
syringe needle and allow the blood to enter the tube until the flow
stops. Never push on the plunger or force blood into the tube.
vii. Implement safety mechanism or devices on the needle
immediately.
viii. Mix any anticoagulant tubes immediately.
B. Evacuated Tube System
i. Let go of the skin and use that hand to grasp the flange of the
vacuum tube holder and push the tube forward until the needle
has completely entered the tube. Do not change hands while
performing venipuncture. The hand performing the venipuncture is
the hand that is holding the vacuum tube holder. The other hand is
free for tube insertion and removal.
ii. Fill the tube until the vacuum is exhausted and the blood flow
stops. Rotate tubes so the label is down.
iii. When the blood ceases, gently remove the vacuum tube from the
needle and holder.
iv. Immediately mix the blood in the anticoagulant tubes by gently
inverting them several times.
v. Insert the second tube onto the needle by using the same motion
as the first tube. Let it fill then remove it with the same motion as
the first tube. Invert it several times if it contains anticoagulants.
vi. When the last tube has filled, remove it from the needle. Ask the
patient to open the hand and release the tourniquet.
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vii. Lightly place a cotton ball above the puncture site and remove the
needle in the same direction as inserted.
viii. Immediately activate the safety device.
ix. Apply pressure to the site for 2 to 3 minutes. Let the patient assist
by holding the pressure if desired. The patient can elevate the arm
but should be instructed not to bend the elbow.
Discard the syringe and needle into a sharps container and the
contaminated cotton ball and other contaminated waste into a red
biohazard bag.
Label all tubes before leaving the patient and verify identification with the
patient ID band or verbally with an outpatient. Label the patient’s tube with:
surname/family name, first name, date of birth, unique numeric identifier,
date taken, and the phlebotomist’s initials. If any special treatment is
required for the specimens, institute the handling protocol. Complete
paperwork.
Check the patient. Observe for signs of stress. When sufficient pressure
has been applied to stop the bleeding, apply a small pressure bandage by
pulling a cotton ball in half, applying it to the puncture site, and placing an
adhesive bandage or tape over it. Instruct the patient to remove the
bandage in 20 minutes. If the patient is sensitive or allergic to latex, use
nonlatex paper tape. If the bleeding has not stopped after 2 to 3 minutes,
have the patient continue to hold direct pressure on the site for another 5
minutes with the arm elevated above the heart and by lying down with the
other arm on a pillow. Recheck after 5 minutes.
Disinfect surfaces and supplies/equipment and dispose of all contaminated
items properly. Remove gloves using proper technique.
Thank the patient, wash hands, record the procedure, and complete the
laboratory requisition.
QUALITY CONTROL:
Quality control of venipuncture equipment is essential
to patient safety and sample quality. Needles must be sterile and visibly inspected for
nonpointed or barbs. The expiration date should be checked each time a new
package of tubes is opened. Use of expired tubes may cause short draws, clotted
anticoagulated samples, improperly preserved samples, and insecure gel barriers.
Properly identify the patient and tests ordered as well as the preparation of the
patient for blood tests. Quality control (QC) procedures on new lots of evacuated
tubes:
a)
b)
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f)
g)
Measure the amount of water drawn into a tube to QC the tube vacuum.
Check anticoagulant tubes for the presence of small clots.
Visually check the appearance of additives.
Check the stability of tubes and gel barriers following centrifugation.
Check stopper integrity and ease of stopper removal.
Document results of the checks.
Notify the manufacturer if defects are discovered.
REFERENCE VALUES:
N/A
PRECAUTIONS:
a)
b)
c)
Wear gloves and a laboratory gown when handling blood/body fluids.
Perform hand hygiene before patient contact.
If swelling is noticed during venipuncture, immediately release tourniquet,
remove needle and apply pressure using gauze pad.
d)
e)
f)
g)
h)
i)
j)
k)
l)
m)
n)
o)
On patients with a bleeding disorder (Hemophilia or von Willebrand's
Disease), use a 21 gauge butterfly needle or smaller. Do not probe if blood
is not obtained immediately. Remove needle and start over.
If first attempt fails, pull needle back slowly, relocate vein, pull skin taut
(anchor vein), and redirect needle. Lateral needle relocation should never
be attempted to access the basilic vein, since nerves and the brachial
artery are in close proximity.
Do not attempt to stick patient more than two times; contact another
phlebotomist.
If patient feels a shooting, electric-like pain, tingling, or numbness, remove
the needle, notify nurse or physician, and document the incident.
If blood flow ceases:
 Raise or lower angle of needle, this may free bevel of needle from wall
of vein.
 Pull needle back slowly. (Needle may have penetrated wall of vein
while changing tubes.)
 Pull skin taut from above or below site. (This may also help to free the
needle from wall of vein.)
 Rotate needle one half turn.
 If venipuncture attempt fails, a new sterile needle/butterfly must be
used.
Change gloves after each patient or when contaminated. Perform hand
hygiene after glove removal.
Wash hands frequently.
Dispose of items in the appropriate containers.
Dispose or clean tourniquet after collection.
Dispose of needles immediately upon removal from the patient’s vein. Do
not bend, break, recap, or re-sheath needles to avoid accidental needle
puncture or splashing of contents.
Never take venipuncture trays into isolation rooms.
Clean up any blood spills with a disinfectant such as freshly made 10%
bleach.
REFERENCES: