American Medical Certification Association Flashcards

Which additive in a lavender-top tube prevents coagulation by binding calcium?

Answer: EDTA

EDTA (ethylenediaminetetraacetic acid) chelates calcium ions to prevent blood from clotting in lavender-top tubes used for hematology.

A patient's arm shows a hematoma forming during venipuncture. What is the FIRST action to take?

Answer: Remove the needle and apply firm pressure

When a hematoma forms, the phlebotomist must immediately remove the needle and apply firm pressure to stop bleeding and limit bruising.

What is the maximum recommended angle for needle insertion during routine venipuncture?

Answer: 30 degrees

The recommended needle insertion angle for venipuncture is 15–30 degrees, with 30 degrees being the accepted maximum for most patients.

Which of the following is the correct order of draw when using a syringe transfer?

Answer: Blood culture, EDTA, coagulation, SST

Syringe transfers follow the CLSI order: blood culture bottles first, then anticoagulant tubes in the standard order of draw.

The AMCA phlebotomy exam requires candidates to demonstrate competency in which primary area?

Answer: Specimen collection, processing, and patient safety

The AMCA Phlebotomy Technician exam focuses on specimen collection procedures, processing protocols, and maintaining patient safety throughout.

A gray-top tube contains sodium fluoride. What is its primary purpose?

Answer: Inhibits glycolysis to preserve glucose levels

Sodium fluoride inhibits the enzyme enolase, halting glycolysis and preserving accurate glucose concentrations in the specimen.

Which action BEST prevents preanalytical error related to specimen integrity?

Answer: Inverting additive tubes the recommended number of times immediately after collection

Proper inversion immediately after collection ensures the additive mixes thoroughly with the blood, preventing clot formation in anticoagulant tubes and incomplete activation in SSTs.