Transcript Skin Puncture

Blood Specimen
Collection
by: Angeli Paula Malang
Objectives:
• Define skin puncture and venipuncture
• Locate the acceptable sites for skin
puncture and venipuncture
• List the supplies necessary for performance
of skin puncture and venipuncture.
• Differentiate the methods of venipuncture
• Differentiate Venous, Arterial, and Capillary
Blood Specimens
What is skin puncture?
Skin-puncture collection is useful
for collection of minimum amounts
of blood from adult or pediatric
patients.
Selecting the proper skin puncture
site is key to obtaining a quality blood
sample.
• Infants: Heel puncture is generally performed
on infants less than 1 year of age.
o Lateral or medial plantar surface of the heel.
o Do not puncture deeper than 2.0 mm. injure the
bone
• Adults and older children: Finger Puncture is
generally performed
o The recommended site is the end segment of the
finger in the middle or ring finger of the nondominant hand.
o The puncture should occur across the fingerprints,
not parallel to them.
Materials needed for skin puncture:
What is Venipuncture?
Venipuncture is the process of
piercing a vein with a needle to withdraw
blood or start an intravenous line for giving
medications.
There are many ways in which blood
can be drawn from a vein. The best method
varies with the age of the patient, equipment
available and tests required.
Methods of Venipuncture
• Evacuated system is used for multiple draws. It
uses plastic hub, a hypodermic needle and a
vacuum tube.
• Syringe method is the most common Because
syringes are manually operated, the amount of
suction applied may be easily controlled.
• The butterfly winged infusion set is frequently
used for collecting blood from pediatric patients
and patients with tiny, fragile veins.
The preferred site is the antecubital
fossa, which is where the arm bends at
the elbow. The vein of choice is the
median cubital vein. The cephalic vein
is not preferred because it has a tendency
to roll but can be used as an alternative to
the median cubital vein. The basilic vein
lies close to the brachial nerve and artery,
and for this reason should be avoided.
Difference between Capillary,
Venous & Arterial blood
• Capillary Blood
o The specimen from a dermal puncture will therefore be
a mixture of arterial and venous blood along with
interstitial and intracellular fluids.
• Venous Blood
o Venous blood is deoxygenated blood that flows from
tiny capillary blood vessels within the tissues into
progressively larger veins to the right side of the heart.
• Arterial Blood
o Deoxygenated blood is pumped from the right side of
the heart to the lungs where it takes up oxygen. The
now oxygenated blood is pumped through the left side
of the heart via arteries.
Materials needed for skin puncture:
•
•
•
•
•
•
•
•
•
Disposable latex gloves
Tourniquet
Adapter
Blood Collection Tubes
Hypodermic needle
Syringe (5cc)
Antiseptic (70% isopropyl alcohol)
2x2 gauze pads or cotton balls
Micropore