NHA Certified Phlebotomy Technician (CPT)Collection RoutineMedium
A phlebotomy technician is preparing to collect a blood specimen for an ammonia level test. Which of the following special handling procedures is required for this specimen?
- APlace in an ice slurry immediately
- BCentrifuge and separate plasma within 30 minutes
- CKeep at room temperature
- DProtect from light
Show answer & explanationAnswer & explanation
Correct answer: A. Place in an ice slurry immediately
Ammonia levels are sensitive to temperature and can falsely increase if not immediately chilled. Placing the specimen in an ice slurry slows down metabolic processes that produce ammonia.
Why the other options are wrong
- B. Centrifugation and separation are standard for many tests, but immediate chilling is paramount for ammonia.
- C. Keeping at room temperature would allow metabolic processes to continue, falsely elevating ammonia.
- D. Protecting from light is typically for bilirubin or vitamin levels, not ammonia.
Ammonia Specimen Handling
Blood specimens for ammonia level testing require immediate chilling in an ice slurry to prevent falsely elevated results due to continued metabolic activity.
- Inhibits enzymatic activity
- Prevents ammonia production post-collection
- Crucial for accurate diagnosis of liver disease or encephalopathy
- Often collected in an EDTA (lavender top) tube
Memory trick: Some specimens are 'Chill' and some 'Shade' – know their special needs.