SKIN PUNCTURE/ CAPILLARY PUNCTURE

SKIN PUNCTURE/ CAPILLARY PUNCTURE

A fingerstick to obtain blood for routine laboratory analysis and usually preferred for children.

Dermal Puncture

SKIN PUNCTURE/ CAPILLARY PUNCTURE are also known as __________.

1.75mm

Length of the lancet: _______.

<2.0mm ; <2.5 mm

The depth of the incision should be ______ for children and ________ for adults.

across the fingerprints or perpendicular

The cut should be oriented _________ to generate a large drop of blood using single deliberate motion.

Lateral plantar heel surface

- the preferred site for newborns and infants

Palmar surface of the non dominant fingers (3rd and 4th fingers)

- the most common site for adults

Earlobes

- the least used site

Enumerate the preferred sites for skin puncture:

• Lateral plantar heel surface – newborns and infants
• Palmar surface of the non dominant fingers (3rd and 4th fingers) – most common
• Plantar surface of the big toe
• Earlobes – least used site

SITES TO AVOID

• Inflamed and pallor areas
• Cold and cyanotic areas
• Congested and edematous areas
• Scarred and heavily calloused areas

Advantages of Skin Puncture

• It is accessible to the operator
• Easy to manipulate
• Ideal for peripheral blood smears.

Disadvantages of Skin Puncture

• Less amount of blood can be obtained
• Additional and repeated test cannot be done
• Blood obtained has tendencies to hemolyze easily.

Lancets

- __________ are sterile, disposable, sharp instruments used for capillary puncture.
- Their blades or points must permanently retract to prevent sharp injuries.

70% isopropyl alcohol

- CLSI recommends using __________to clean surface of the skin before puncturing with a lancet or other sharp device.

Gauze or cotton balls

- _____________ are used to wipe away the first blood drop to eliminate alcohol residue and excess tissue fluid.

first blood drop

- Gauze or cotton balls are used to wipe away the _______ to eliminate alcohol residue and excess tissue fluid.

Bandages

- _______ are used to cover the site after collection.

MICROCOLLECTION CONTAINERS

Also known as microtubes

MICROCOLLECTION CONTAINERS

Special small plastic tubes used to collect tiny amounts of blood obtained from capillary punctures

MICROCOLLECTION CONTAINERS

Often referred to as bullets because of their size and shape

MICROHEMATOCRIT TUBES

Disposable, narrow-bore plastic or plastic-clad glass capillary tubes that fill by capillary action and typically hold 50-75 uL of blood.

MICROHEMATOCRIT TUBES

Also known as capillary tubes

MICROHEMATOCRIT TUBES

Used primarily for manual hematocrit (PCV) determinations

Packed Cell Volume

PCV

MICROHEMATOCRIT TUBES

Coated with ammonium heparin or plain

red or green

Heparin tubes have _______ band on one end

blue

Nonadditive tubes have _____ band

WARMING DEVICES

• Warming the sites increases blood flow up to seven times and is especially important when performing heel sticks.
• Water temperature must not exceed 42ºC or it could scald the patient

42ºC

Water temperature must not exceed ______ or it could scald the patient

SEALANTS

- are claylike substances used to seal one end of microhematocrit tubes

4-6mm

The clay plug should be _____ long

1st: clay sealant
2nd: paraffin wax

- when sealing the microhematocrit tubes what are the two things you are going to use?

PROCEDURE FOR SKIN PUNCTURE

• Identify the patient properly
• Choose an appropriate site for collection
• Clean the site with 70% alcohol
• Hold finger between your index finger and thumb
• Puncture the finger using a quick, smooth motion
• Wipe away the first drop of blood
• Collect blood sample
• Apply pressure to puncture site
• Label specimen in sight of patient

INDICATIONS FOR CAPILLARY PUNCTURE

• Can be done if small amount of blood is required.
• There are no accessible veins
• Available veins are fragile or must be saved for other procedures such as chemotherapy
• Blood is to be obtained for POCT procedures such as glucose monitoring
• Capillary blood is the preferred specimen for some tests such as newborn screening

RED BAND

Capillary blood obtained through skin puncture transferred to an anticoagulated capillary tube (HEPARIN) – with ______.

BLUE BAND

EDTA-anticoagulated blood transferred to a non-anticoagulated capillary tube – with ______

2/3 TO ¾ FULL

▪ NOTE: CAPILLARY TUBES MUST BE _____.

air bubbles and spaces

In collecting the sample by microhematocrit tubes avoid ________.

clay sealant ; paraffin

Sealed first with a ______ then ______.

Label the specimen properly with:

• patient’s full name
• age
• date of birth
• time and date of collection
• initials of the phlebotomist

ORDER OF DRAW (MICROTAINER)

• Blood Gases (CBGs)
• Slides & Smears
• EDTA tubes
• Other additive microtainer
• Serum microtainer

Clinical and Laboratory Standards Institute

CLSI

Heparin

_______ is a natural anticoagulant found in the body

capillary action

capillary tubes are fill by __________ and typically hold 50-75 uL of blood.

50-75 uL

- the capillary tube can typically hold ______ of blood