Needle Components & Equipment
This needle component prevents blood from leaking out before a tube is inserted.
Rubber sleeve
Drawing a serum tube after a lavender tube can falsely elevate potassium levels due to contamination with this additive.
EDTA
This is the correct angle of insertion for routine venipuncture.
15–30 degrees
What must be verified using at least two identifiers before performing any blood collection?
Patient identity
Which tube must always be collected first to prevent contamination from other additives?
Blood culture tubes
This part of the needle must face upward during venipuncture to allow smooth entry into the vein and reduce tissue trauma.
Bevel
Which tube color contains sodium citrate and must be completely filled to ensure accurate coagulation test results?
Light blue top
This vein is the first choice for venipuncture due to stability and size.
Median cubital vein
What patient response is characterized by a sudden drop in blood pressure and heart rate during or after venipuncture?
Vasovagal syncope
Which quality control step ensures specimens are linked to the correct patient and test order?
Proper specimen labeling
Using a needle gauge that is too small most commonly causes this specimen problem.
Hemolysis
How many times must EDTA tubes be inverted to properly mix the additive without causing hemolysis?
8-10 times
Failure to anchor the vein during venipuncture most commonly results in this technical complication.
Vein rolling (missed vein)
What immediate action reduces injury risk when a patient reports dizziness during venipuncture?
Discontinuing the procedure
Which tube color must be drawn immediately after blood cultures?
Light blue
A butterfly needle is preferred over a straight needle when drawing blood from a
pediatric patients or patients with fragile veins
Which tube additive prevents glycolysis by inhibiting glucose metabolism in the blood specimen?
Sodium fluoride (gray top)
Failure to release the tourniquet before withdrawing the needle most directly increases the risk of this complication.
Hematoma and hemolysis
What physiologic change occurs immediately before loss of consciousness during a vasovagal episode?
Decreased blood pressure
Which tube color must always be drawn before lavender to prevent EDTA contamination?
Red or gold (serum tube)
The most critical determinant in preventing needle-related specimen rejection is maintaining appropriate blood flow velocity, which is primarily controlled by this needle characteristic.
Gauge size
Which tube requires gentle inversion rather than shaking to maintain specimen integrity?
All additive tubes
Repeated probing during venipuncture increases the risk of nerve injury and this vascular complication.
Hematoma
Phlebotomy practice standards require immediate response to patient distress to prevent injury and comply with this ethical principle.
Nonmaleficence
Standard order of draw
Yellow → Light Blue → Red → Gold → Green → Lavender → Gray