1
Which tube contains EDTA and is used for CBC testing?
Lavender
A hemoglobin level below normal indicates what general condition?
Anemia
What is the maximum time a tourniquet should remain on a patient?
1 Full Minute
What is the term for fainting during a blood draw?
Syncope
What test measures average blood glucose over 2–3 months?
HbA1c
Which tube must be completely filled to maintain a 9:1 ratio?
Light Blue
Which electrolyte is most dangerous when elevated due to its effect on the heart?
Potassium
What happens if you shake a lavender tube?
Hemolysis/Destruction of cells
What early signs indicate a patient may faint?
Pallor, sweating, dizziness
Why must the first drop of capillary blood be wiped away?
Contains tissue fluid (interstitial fluid)
Which tube is used for blood cultures and must be drawn first?
Yellow
A patient with elevated WBC is most likely experiencing what?
Infection or inflammation
What occurs if a red tube is centrifuged before clotting is complete?
Fibrin strands/invalid specimen
What is the immediate action if a patient reports sharp, shooting pain during venipuncture?
Stop procedure immediately
Why should you NOT squeeze the finger during capillary collection?
What additive is found in gray tubes and what is its function?
Fluoride/prevents glycolysis
A potassium level above 5.0 mEq/L places the patient at risk for what?
Cardiac Arrythmias
What is the most common cause of rejected specimens in phlebotomy?
Hemolysis
Why are patients on anticoagulants at higher risk during blood draws?
Increased Bleeding Risk
What type of blood is collected during a capillary puncture?
Mixture of arterial, venous, and tissue fluid
Explain why the order of draw must be followed and what can happen if it is not.
Prevents additive carryover, incorrect order leads to contaminated samples and false lab results
A patient presents with low hemoglobin, low hematocrit, and low RBC count. What is the most likely condition?
Anemia
What is hemoconcentration and what causes it during a blood draw?
Increased concentration of blood components, caused by prolonged tourniquet use.
Describe the physiological mechanism behind syncope during a blood draw.
Vasovagal response- decreased heart rate & blood pressure-reduced cerebral blood flow
Why is HbA1c considered more reliable than a single glucose reading?
Reflects long-term levels 2-3 months, not affected by daily changes