CLC Specimen Collection, Handling & Pre-Analytical Processes Flashcards
6 cards from real CLC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 CLC Specimen Collection, Handling & Pre-Analytical Processes flashcards as text
A laboratory consultant notices that hemolysis interference is causing falsely elevated potassium results. Which pre-analytical intervention would best reduce this problem?
Answer: Training phlebotomists on proper technique and minimizing tourniquet time
The most effective long-term intervention is training phlebotomists to use proper technique and limit tourniquet time, which directly reduces hemolysis at the source.
Which labeling requirement is considered the minimum for patient specimen identification according to laboratory safety and accreditation standards?
Answer: Patient full name and date of birth (or second unique identifier)
At minimum, specimens must be labeled with the patient's full name and a second unique identifier (such as date of birth or medical record number) to prevent misidentification.
A 24-hour urine collection for creatinine clearance requires special pre-collection instructions. Which instruction is most critical for accurate results?
Answer: Discard the first void, then collect all urine for exactly 24 hours
The standard 24-hour urine protocol requires discarding the first morning void (to clear residual urine), then collecting all urine for the next 24 hours to ensure a complete timed collection.
When collecting a blood culture, which antiseptic preparation sequence follows current best practice to minimize contamination rates?
Answer: 70% isopropyl alcohol followed by chlorhexidine gluconate (or povidone-iodine), allowed to dry fully
Current best practice for blood culture collection uses 70% isopropyl alcohol followed by chlorhexidine gluconate (or povidone-iodine), allowed to fully dry to minimize skin flora contamination.
A laboratory consultant is reviewing cold agglutinin test pre-analytical requirements. What is the critical handling step for this specimen?
Answer: Keep the specimen at 37°C from collection through serum separation
Cold agglutinin specimens must be kept warm (37°C) from collection through serum separation because cooling causes antibody binding to RBCs, making them undetectable.
Which pre-analytical variable most commonly causes a falsely decreased glucose result when specimens are not processed promptly?
Answer: Glycolysis by RBCs and WBCs consuming glucose over time
Cellular metabolism (glycolysis) continues in unprocessed whole blood, consuming glucose at a rate of approximately 5–7% per hour at room temperature, causing falsely low glucose results.