Laboratory Procedures and Specimen Handling Flashcards
6 cards from real NHA practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Laboratory Procedures and Specimen Handling flashcards as text
What is the correct order of draw for a light blue top tube, a lavender top tube, and a serum separator tube (SST)?
Answer: Light Blue, SST, Lavender
The standard order of draw prevents additive cross-contamination. Coagulation tubes (light blue) are drawn first, followed by serum tubes like the SST, and then tubes with other additives like EDTA (lavender).
The additive in a lavender-topped collection tube is:
Answer: EDTA
Lavender (or purple) top tubes contain the anticoagulant Ethylenediaminetetraacetic acid (EDTA). EDTA works by binding to calcium in the blood, which prevents the clotting cascade from occurring and preserves blood cell morphology for hematology tests.
Which type of urine specimen is required for a culture and sensitivity test?
Answer: Clean-catch midstream specimen
A clean-catch midstream specimen is necessary to minimize contamination from external bacteria. This ensures that any microorganisms grown in the culture are from the patient's urinary tract, leading to an accurate diagnosis.
Which of the following is an example of a CLIA-waived test commonly performed in a medical office?
Answer: Urine pregnancy test
CLIA-waived tests are simple procedures with a low risk of an incorrect result. A rapid urine pregnancy test is a prime example of a waived test that medical assistants are trained to perform.
What is the most critical step in ensuring the accuracy of a laboratory result?
Answer: Properly labeling the specimen
Properly identifying the patient and correctly labeling the specimen at the time of collection is the most critical step. A mislabeled or unlabeled specimen can lead to a catastrophic error in diagnosis and treatment.
When preparing a blood specimen for transport to an outside laboratory, what action should the medical assistant take?
Answer: Complete a requisition and place it in the outer pocket of the transport bag
The specimen must be placed in a biohazard transport bag, and the completed laboratory requisition form should be placed in the bag's outer pocket. This keeps the form clean and dry while ensuring all necessary information travels with the specimen.