ROUTINE CAPILLARY PUNCTURE Flashcards
When should capillary puncture be used?
Ideal for small children when only a small volume of blood is needed.
Advantageous in certain adult populations whose veins are inaccessible:
Severely burned.
Cancer patients
Obese
Geriatric patients
Point of care testing (POCT)
Patients performing tests on themselves.
Special procedures that require capillary blood
The capillary puncture should not be used on patients who ____
Should NOT be used on patients who are extremely dehydrated or cold
INDICATIONS FOR PERFORMING CAPILLARY PUNCTURE: Adults
No accessible veins
To save veins for chemotherapy
Clotting tendencies
POCT procedures such as glucose monitoring
INDICATIONS FOR PERFORMING CAPILLARY PUNCTURE: Children and Infant
To prevent anemia
To prevent cardiac arrest from removal of large quantities of blood
Venipuncture too difficult
To prevent injury
CAPILLARY EQUIPMENT
Lancet
Micro-Collection Containers
Hematocrit Tubes
Plastic/ Clay Sealant
Microscope Slides
Warming Devices
Lancets should be
Sterile and disposable
Retractable blade
Either finger or heel
Collects tiny amounts of blood.
MICRO-COLLECTION CONTAINERS
Manual Hct
HEMATOCRIT TUBES
Used to seal the tip of capillary tubes
PLASTIC/CLAY SEALANT
Smearing
MICROSCOPE SLIDES
SITE SELECTION
Ring or great finger
Infant’s heel
Earlobe
Why should the non-dominant hand be used when performing capillary puncture?
less calloused
What should be the direction of the puncture?
opposite direction of the fingerprint
Capillary SPecimen is a mixture of
arterial, venous and capillary
blood
- fluid outside of the body’s cells (extracellular)
Interstitial fluid
fluid in the tissue spaces between cells
Interstitial fluid
fluid within cells from surrounded tissues
Intracellular fluid
contains water and dissolved solutes (electrolytes) and proteins
Intracellular fluid
Puncture blood
Higher result in
Glucose
Puncture blood:
Lower result in
Total Protein, Calcium and Potassium
Choose a finger that is not ___ or __________ for the puncture site
cold or edematous
Clean the puncture site with ______________________ and let it dry.
70% Isopropyl alcohol
Massage the _________ of the finger to stimulate blood flow.
lower portion
Puncture the skin while pressing the area ______ the puncture site. Dispose puncture device.
below
Wipe away the first drop of blood with a___________.
sterile dry gauze
Collect the sample in the chosen container in a ______________ and a gentle pressure is applied to the finger
downward angle
In cleaning the site, do not use
Povidone-lodine (Betadine)
What would happen if betadine is used to clean the site?
this will result to an increase in
Potassium
As you hold the patient’s hand, position the hand so that the puncture site permits the _________________ of blood.
downward flow
T or F | Do not scrape the blood from the surface of the skin.
T
If blood lodges in the tip of the device, a ____ on the hard surface should facilitate blood flow.
tap
T or F | Rotate the tube after every drop
T
OBTAINING BLOOD SAMPLES FROM BABIES: SITES TO AVOID
Medial or big toe side.
Lateral or little toe side.
Central arch area of the foot.
DEPTH OF PUNCTURE: Premature
0.85mm
DEPTH OF PUNCTURE: Full-Term
2mm
Puncture of the fingers of infants __________________ should be done only after other options are considered.
<1 year old
Distant to the _________________________ of the infant’s fingers is 1.2-2.2mm.
bones and main nerves
Distant to the bones and main nerves of 6 months- 8y/o
1.5mm
Distant to the bones and main nerves of Child over 8 y/o
2.4mm
Distant to the bones and main nerves of Adult
2.4mm
PRECAUTIONS: When collecting blood from babies
Excessive crying
Hemolysis
Newborn with elevated bilirubin
Concentration of chemical constituents in capillary blood.
Collecting sequential sample
CAUSES OF HEMOLYSIS
Alcohol used to clean the skin was not allowed to dry.
Finger or heel was squeezed too vigorously in an attempt to produce greater blood flow.
Newborn infants have increased red cell fragility and high RBC volume.
Blood was scraped off, instead of allowing it to flow into the micro-collection container.
DIFFERENCES IN LABORATORY VALUES IN CAPILLARY BLOOD IN RELATION TO VENOUS BLOOD: Glucose
Higher in capillary blood
DIFFERENCES IN LABORATORY VALUES IN CAPILLARY BLOOD IN RELATION TO VENOUS BLOOD: Total Protein
Lower in capillary blood
DIFFERENCES IN LABORATORY VALUES IN CAPILLARY BLOOD IN RELATION TO VENOUS BLOOD: Calcium
Lower in capillary blood
DIFFERENCES IN LABORATORY VALUES IN CAPILLARY BLOOD IN RELATION TO VENOUS BLOOD: Potassium
Lower in capillary blood
ORDER OF DRAW FOR A CAPILLARY PUNCTURE
- Gas tubes
- Slides
- EDTA (purple top tube)
- Heparin- light or dark green top tube
- Other additive micro-collection cont.
- Serum - red top or amber tube with red top.
