Elsa
Why are capillary blood gasses less desirable than arterial blood gasses (ABGs)
Capillary samples are more prone to contamination from tissue fluids, leading to altered results.
Capillary blood is a mix of arterial and venous blood, which can lead to lower oxygen (PaO₂) values compared to pure arterial blood.
Capillary samples can show higher carbon dioxide (PaC
A capillary puncture should be done rather than a venipuncture in all of the following situations EXCEPT when
a) a child is less than 1 year old.
b) a light-blue-top tube is needed.
c) the patient has difficult veins.
d) the test uses very little blood.
b) a light-blue-top tube is needed.
Which microtube would be used to collect a specimen for a CBC?
Purple/Lavender
If the alcohol is still wet when a capillary puncture is made it can
cause hemolysis of the specimen.
lead to errors in the testing process.
prevent round drops from forming.
This type of lancet is commonly used for heel sticks in infants.
Heel Lancet
What is the Clinical and Laboratory Standards Institute (CLSI) recommended maximum depth of heel puncture?
2.0mm for Infants
The purpose of wiping away the first drop of blood during skin puncture is to
eliminate tissue fluid contamination.
What is PKU?
A hereditary inability to metabolize phenylalanine
Capillary punctures that are deeper than recommended are more painful because pain fibers increase in abundance below
a) 0.5 mm
b) 1.2 mm
c) 1.5 mm
d) 2.4 mm
C 1.5
Which step should be performed first before a capillary puncture?
A) Squeeze the fingertip
B) Clean the site with alcohol
C) Make the puncture
D) Apply a bandage
B) Clean the site with alcohol
Why are EDTA specimens obtained before other specimens when collected by skin puncture?
To prevent contamination from carryover
Capillary puncture blood most closely resembles
arterial blood.
It is necessary to control depth of lancet insertion during capillary puncture to avoid
injuring the heel bone.
Which of the following scenarios represents correct capillary puncture technique?
a) Puncturing perpendicular to the fingerprint whorls
b) Scooping up blood that is running down the finger
c) Using povidone-iodine to clean the heel of an infant
d) Wiping the alcohol dry so the puncture doesn't sting
a) Puncturing perpendicular to the fingerprint whorls
This device is used to make a small puncture in the skin to obtain a capillary blood sample.
Lancet
Why should a laboratory report form indicate the fact that a specimen has been collected by capillary puncture?
Because test results can vary depending on the method of collection
What does the term “calcaneus” mean?
Heel bone
What is the purpose of warming the site before skin puncture?
Specific Number of times
It increases blood flow up to seven times.
A laboratory report form should indicate when a specimen has been collected by capillary puncture because
some test results vary with specimen source.
Used lancets should be disposed of in this container.
Sharps
Which of the following is the safest area for infant heel puncture?
The lateral plantar surface
Capillary puncture blood reference ranges are higher for which of the following analytes?
Glucose
Which of the following is a preferred capillary puncture site?
a) Earlobe
b) Little finger
c) Middle finger
d) Thumb
c) Middle finger
The blood specimen for which testing is placed in circles on special filter paper?
PKU
If a patient's hands are cold, the blood flow can be poor. The best solution is this.
Warming