LAB MANUAL - CAPILLARY BLOOD COLLECTION Flashcards
Implies puncturing the ________ layer of the skin to access the capillary beds that run through the subcutaneous layer of the skin.
dermal
Capillary Blood Collection: Preferred method of blood specimen collection for _____ and _______
newborns and infants
CLSI
Clinical Laboratory Standards Institute
for infants less than one year of age
Heel stick
children older than one-year
Fingerstick
CAPILLARY BLOOD MAY ALSO BE USED FOR ADULTS UNDER CERTAIN CIRCUMSTANCES INCLUDING:
Patients with fragile, superficial, or difficult to access veins.
Patients requiring only one blood test for which a capillary specimen is appropriate.
Point-of-care testing where only a few drops of blood are needed.
Patients where multiple unsuccessful venipunctures have already been performed, especially if the test(s) requested requires only a small volume of blood.
Patients with burns or scarring in venous blood collection sites.
Extremely obese patients
Patients requiring frequent blood tests.
Patients receiving IV therapy in both arms or hands
Patients at risk for serious complications associated with venipuncture, venous thrombosis, or deep venous puncture.
Patients whose veins are “reserved” for intravenous therapy or chemotherapy.
CAPILLARY BLOOD COLLECTION IS INAPPROPRIATE FOR:
Severely dehydrated patients
Patients with poor circulation
Coagulation studies requiring plasma specimens.
Tests that require large volumes of blood (such as Erythrocyte Sedimentation Rate and blood cultures).
THE FOLLOWING TESTS ARE COMMONLY PERFORMED USING CAPILLARY BLOOD:
Point-of-Care testing (POCT, i.e. blood glucose monitoring)
Complete blood count, hemoglobin, and hematocrit
Peripheral Blood Smear (manual slide for white blood cell differential)
Neonatal Blood Gases
Neonatal Bilirubin
Neonatal Screening (filter paper or bloodspot testing)
Electrolytes.
For the order of draw in Capillary Blood Collection, CLSI recommended to collect_________ first, as the blood becomes an increasingly more like venous blood if the collection is delayed.
blood gases
If collection of blood for a CBC is
delayed, there is an increased likelihood of erroneous cell counts due to ____________.
platelet clumping
To minimize effects of platelet clumping, the following order is recommended:
- Blood Gases
- EDTA tubes
- Other additive tubes
- Serum tubes
EQUIPMENT FOR CAPILLARY SPECIMEN COLLECTION
PUNCTURE DEVICES
INCISION DEVICES
LASER LANCETS
MICROHEMATOCRIT CONTAINERS
MICROHEMATOCRIT TUBES AND SEALANTS
Used to puncture the skin by inserting either a needle or blade vertically into the tissue.
PUNCTURE DEVICES
Preferably for sites that are repeatedly punctured.
PUNCTURE DEVICES
slice through capillary beds
INCISION DEVICES
Create less painful than puncture devices and require fewer repeat incisions and shorter collection times.
INCISION DEVICES
Recommended for infant heel sticks.
INCISION DEVICES
skin puncture should be:
_________, _________, ________ with a _________ to reduce the possibility of accidental needlestick injuries and reuse.
sterile, disposable, single-use device with a permanently retractable blade or needle
use a safety type of laser (in compliance with laser and medical device safety standards) that generates high energy when the laser comes in contact with the skin
Laser lancet
A small hole is created in a very short time (Less than 1/10000 second) with very little pain.
Laser lancets
Some are fitted with narrow plastic capillary tubes to facilitate specimen collection.
MICROHEMATOCRIT CONTAINERS
Have color-coded caps or stoppers that correspond to ETS blood collection tubes, and markings for minimum and maximum fill levels
measured in microliters.
MICROHEMATOCRIT CONTAINERS
Are narrow-bore plastic or plastic-clad glass capillary tubes that fill by capillary action.
MICROHEMATOCRIT TUBES
MICROHEMATOCRIT TUBES can hold up to ___ - ___ of blood
50 to 70 uL
The tiny tubes are used for manual hematocrit
or packed cell volume determinations
Microhematocrit Tubes
The walls of red-banded tubes are coated with __________
ammonium heparin
Are used in collecting hematocrit tubes directly from a capillary puncture.
red-banded tubes
Plain, uncoated
Used when blood collected from a lavender top tube.
Blue-banded
What should be taken into
consideration when selecting the skin
patient’s age
accessibility of the puncture site blood volume required
Select a site that is
warm
pink
free of any calluses
burns
cuts
scar
bruises
rashes
The site should NOT be
cyanotic (bluish from lack of oxygen)
edematous (swollen)
or infected.
Avoid skin areas that have evidence of
previous punctures
Recommended site for capillary collection on adults and children over one year of age.
Palmar surface of the distal (end) segment or the THIRD (middle) or FOURTH (ring) finger of the nondominant hand.
The puncture should be made slightly off center from the central, fleshy portion of
the fingertip and if using a blade-type puncture device, __________ to the fingerprint whorls.
perpendicular
Puncturing _______________________ may cause the blood to flow the pattern of the fingerprint, redirecting the flow and making it more difficult to collect.
along or parallel to the whorls
The ___________ is often calloused and potentially more sensitive to pain due to additional nerve endings.
index finger
The _______ also may be calloused and has a pulse, indicating arterial presence, and, therefore, should be avoided.
thumb
The distance between the skin surface and the bone in the_________ also makes it unsuitable for puncture.
fifth finger
The _____ and _____ of the finger should be avoided as the tissue is about half as thick as the central portion of the fingertip.
side and tip
The recommended site for heel punctures is the
lateral (outside) or medial (inside) plantar surface of the heel
In small or premature infants, the heel bone (calcaneus) may be no more than _____ beneath the skin surface and no more than half this distance at the posterior curvature of the heel.
2.0 mm
When using incision devices, puncturing the heel at a ________ to the length of the foot is recommended.
90° angle
FOR INFANTS, PUNCTURES MUST NOT BE PERFORMED ON:
The posterior curvature of the heel.
The central area of an infant’s foot (area of the arch).
The fingers of a newborn or infant less than one year old
Earlobes
