I.
Principle
Blood specimens obtained by skin puncture are especially important in
pediatrics, because small but adequate amounts of blood for laboratory tests can
be obtained with this technique. It is also the primary sample used when
collecting blood for bedside testing such as whole blood glucose and
hemoglobin. The quantity of blood removed and the avoidance of injury during
specimen collection are important considerations. Therefore, blood collection by
skin puncture is the technique of choice for collecting small amounts of blood
from children, especially newborns. In children, depending on the age, skinpuncture blood may be obtained from the heel or the finger.
II.
Supplies
Assemble the following supplies on a tray or in a drawing room:
 Microtainers
 Retractable lancets
 Alcohol, 78% isopropyl, or alcohol prep pads
 Gauze pad or cotton ball
 Bandages
 Heel warmer
Lancets
Various devices for skin puncture are available. Refer to the manufacturer’s
directions for optimum performance.
In small or premature infants, the heel bone may be no more than 2.0 mm
beneath the plantar heel-skin surface. Puncturing deeper than 2.0 mm on the
plantar surface of the heel of small infants may therefore risk bone damage. The
major blood vessels of the skin are located at the dermal-subcutaneous junction,
which in the newborn’s heel is 0.35 to 1.6 mm beneath the skin surface.
Therefore, even in the smallest infant, a puncture 2.0 mm deep on the plantar
surface of the heel will penetrate the major skin vasculature and not risk puncture
of the bone.
III.
Patient Preparation
A.
Patient identification- Testing personnel must positively identify the
patient that is being drawn. The following step ensure patient
identification:
1.
In an Outpatient setting:
a.
Ask the patient to state their full name, including the
spelling of an unusual name. If the patient is very
young, ask his/her parents or guardian to state the
name and/or the correct spelling.
b.
Compare the name with that on the patient chart you
have.
2.
B.
C.
D.
E.
IV
In an inpatient setting:
c.
Compare your information with the patient’s name
and hospital number found on the patient’s wristband.
d.
If the patient is old enough, identify yourself to the
patient stating that you have come to test their blood.
Reassuring the Patient
Testing personnel must gain the patient’s confidence and assure
him that although the puncture will be slightly painful, it will be of
short duration. Patients should never be told that “this will not hurt,”
and they should be told when the needle enters the skin so as to
avoid fright.
Determine whether the patient has fasted (if necessary)
Some tests require the patient to fast or to eliminate certain foods
from the diet before the blood drawing. Time and diet restrictions
vary according to the tests. Such restrictions are needed to ensure
accurate results.
Verify that the patient is free of latex allergies.
Assemble the necessary supplies, wash your hands, and put on
gloves.
Procedure for Heelstick
A.
B.
C.
D.
E.
F.
G.
Prewarm the infant’s heel with a warm, wet towel (or other warming
device) at a temperature no higher than 42C for three to five
minutes (if the temperature used to warm the heel is too high, you
risk burning the baby). This is essential for capillary blood gas
sample collection, and it greatly increases the blood flow for
collection of other specimens.
Clean the chosen puncture site with alcohol and allow the site to
thoroughly dry. Use the sides of the heel. Do not perform
punctures on the posterior curvature of the heel. Do not puncture
through previous sites which may be infected. (See training
manual for details on selecting a puncture site).
If possible, place the baby in a prone position (on stomach). This
may not be possible in the neonatal intensive care unit.
Hold the patient’s heel firmly to prevent sudden movement and to
facilitate adequate puncturing.
Select the appropriate retractable lancet, position it above the
selected site, and activate. Discard of used lancet in approved
puncture-resistant sharps container.
Puncture sites should be oriented perpendicular to the skin print
lines so the blood drop will well up, and should not be in the same
place as a previous heel stick.
After the chosen site has been prepared and punctured, the first
drop of blood should be wiped away with a gauze pad, since the
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first drop is most likely to contain excess tissue fluid. Discard of
gauze in a biohazard container.
Newborns often do not bleed immediately. If the blood is not free
flowing, blood flow may be enhanced by holding the puncture site
downward and gently applying intermittent pressure to the
surrounding tissue. Strong repetitive pressure (milking) must not
be applied. Milking may cause hemolysis or tissue-fluid
contamination of the specimen.
Fill the testing device as needed by gently scooping up the drops of
blood and allowing them to roll into the testing device.
Drops of blood should be allowed to flow freely.
After blood has been collected from an infant’s heel, the foot should
be elevated above the body and a clean gauze pad should be
pressed against the puncture site until the bleeding stops.
Do not use adhesive bandages on infants. Adhesive bandages can
cause irritation to an infant’s skin, and an older infant might remove
the bandage, put it in its mouth, and aspirate it.
Continue with the testing at the bedside (see individual testing
procedures for specific instructions). If sample is to be taken to
another location for testing, properly label the specimen with
patient’s name and/or MR#.
Remove gloves and wash hands. Discard of gloves, lancets, and
other used materials in their appropriate containers.
Procedure for Fingerstick
NOTE:
A.
B.
C.
D.
E.
Fingersticks should not be performed on infants younger
than 6 months of age due to the short distance between the
finger bone and the skin surface.
Clean the chosen puncture site with alcohol and allow the site to
thoroughly dry. Perform the puncture on the center of the palmer
surface the finger- not at the side or tip of the finger, because the
tissue on the side and tip of the finger is about half as thick as the
tissue in the center of the finger.
The middle finger and ring finger are the preferred site, because the
thumb has a pulse and the index finger may be more sensitive or
callused. The fifth finger must not be puncture, because the skin is
too thin. (See training manual for details on selecting a puncture
site). Avoid a finger that is cold, cyanotic (blue), swollen, or
inflamed.
The patient should be positioned so that the finger is steady and
supported in a comfortable position.
With your thumb and index finger, grasp the patient’s finger about
three inches from the tip of the finger.
With your other hand, hold the sides of the patient’s finger.
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VI.
Moving your supporting hand toward the tip of the patient’s finger.
Applying a massaging motion to the fleshy portion of the finger.
Repeat this massaging process five or six times.
Clean the chosen puncture site with alcohol and allow the site to
thoroughly dry.
Select the appropriate retractable lancet, position it above the
selected site, and activate. Discard of used lancet in approved
puncture-resistant sharps container.
Puncture sites should be oriented perpendicular to the lines of the
fingerprint (across the fingerprint).
If the cut is made across the fingerprints and the area has been
wiped dry, the blood should well up into a large rounded drop. (If
the cut has been made along the lines of the fingerprint, the blood
will stream down the finger).
After the chosen site has been prepared and punctured, the first
drop of blood should be wiped away with a gauze pad, since the
first drop is most likely to contain excess tissue fluid. Discard of
gauze in a biohazard container.
If blood does not flow freely, increase blood flow by holding the
finger downward and applying gentle continuous pressure above
the puncture site. Do not massage the area since this may
contaminate the blood sample with tissue fluid.
If blood does not flow easily after gentle pressure, make another
puncture using a new sterile lancet.
Fill the testing device as needed by gently scooping up the drops of
blood and allowing them to roll into the container.
Drops of blood should be allowed to flow freely.
After blood has been collected from the patient’s finger, place a
piece of gauze on the site and apply gentle pressure to stop the
blood flow.
Apply bandage to puncture site after bleeding has stopped.
Continue with the testing at the bedside (see individual testing
procedures for specific instructions). If sample is to be taken to
another location for testing, properly label the specimen with
patient’s name and/or MR#.
Remove gloves and wash hands. Discard of gloves, lancets, and
other used materials in their appropriate containers.
Additional Considerations
Blood must not be obtained from the:

Earlobe.

Central area of an infant’s heel.

Fingers of a newborn.

Swollen or previously punctured site, because accumulated tissue
fluid will contaminate the blood specimen.
VII.
References
NCCLS Procedures and Devices for the Collection of Diagnostic Blood
Specimens by Skin Puncture; Approved Standard- Fourth Edition, September
1999
NCCLS Specimen Collection 1989. 6.14-3.
Blumenfeld, TA: Clinical Application of Microchemistry. In Werner M(ed): MicroTechniques for the Clinical Laboratory: Concept and Application, pp 1-15. New
York, John Wiley & Sons, 1976.
Blumenfeld, TA, Turi GK, Blanc WA: Recommended Sites and Dept. of Newborn
Heel Skin-Punctures Based on Anatomic Measurements and Histopathology,
Lancet 1: 213, 1979.
Meites, S, Levitt MS, Blumenfeld, TA, Hammond KB, Hicks JM, Jill GJ, Sherwin
JE, Smith EK: Skin Puncture and Blood Collecting Technique for Infants, Clinical
Chemistry 25: 183-189, 1979.
Blumenfeld TA, Hertelendy WG, Ford SH: Simultaneously Obtained Skin
Puncture Serum, Kin Puncture Plasma and Venous Serum compared and Effects
of Warming the Skin Before Puncture. Clinical Chemistry 23: 1705, 1977.
Michealsson M, Sjolin S: Hemolysis in Blood Samples from Newborn Infants.
Acta Pedatric Scand 54: 325-330, 1965.
Hicks JR, Rowland GL, Buffone GJ: Evaluation of a New Blood Collection Device
(microtainer) That is Suited for Pediatric Use. Clinical Chemistry 22: 2034-2036,
1976.
Sell EJ, Hansen RC, Struck-Pierce S: Calcified Nodules on the Heel: A
Complication of Neonatal Intensive Care. J Pediatr 96: 473-475, 1980.
Feusner JH, Behrens JH, Detter JC, Cullen TC: Platelet Counts in Capillary
Blood. AM J Clin Pathol 72: 410-414, 1979.