Phlebotomy and Specimen Collection Flashcards

What does a light blue-top tube contain, and what test is it used for?

Answer: Sodium citrate; used for coagulation studies

Light blue-top tubes contain sodium citrate, an anticoagulant that binds calcium to prevent clotting, making them essential for PT, PTT, and INR coagulation tests.

What is the minimum number of times a lavender-top tube should be inverted after collection?

Answer: 8 to 10 times

Lavender-top tubes should be gently inverted 8 to 10 times to ensure EDTA is fully mixed with the blood and prevent clotting.

Which of the following specimens must be kept warm (at body temperature) after collection?

Answer: Cryoglobulin specimen

Cryoglobulin specimens must be kept at 37°C (body temperature) because cryoglobulins precipitate at cooler temperatures, which would affect test results.

What is the proper disposal method for used needles after venipuncture?

Answer: Place uncapped needle directly into a sharps container

Used needles must be immediately discarded uncapped into an approved sharps container to prevent needlestick injuries and comply with OSHA standards.

Which laboratory test requires a fasting specimen from the patient?

Answer: Fasting blood glucose

Fasting blood glucose requires the patient to fast for at least 8 hours because recent food intake raises blood sugar levels and produces inaccurate results.

When collecting a blood culture specimen, which site preparation technique is used?

Answer: Povidone-iodine or chlorhexidine after alcohol

Blood culture sites require a two-step process: 70% alcohol followed by povidone-iodine or chlorhexidine to achieve higher-level antisepsis and minimize contamination.

What does 'QNS' mean on a laboratory specimen rejection label?

Answer: Quantity Not Sufficient

QNS stands for Quantity Not Sufficient, indicating the collected specimen volume is too low to perform the required laboratory test.