Which test is commonly performed with Dark Green tube samples?

• A. Electrolytes
• B. Blood cultures
• C. TSR tests
• D. Ammonia

Answer: (D)

The Dark Green tube is specifically designed for the collection of blood samples for certain tests, one of which is ammonia testing. The additive in the Dark Green tube is sodium heparin, an anticoagulant that prevents the blood from clotting, making it ideal for tests where the sample needs to remain in a liquid state for analysis. Ammonia levels in the blood can be indicative of liver function, and therefore, measuring ammonia requires a sample that has been treated in a way that preserves its integrity; the Dark Green tube serves this purpose effectively.

While other tests like electrolytes could potentially be run on a variety of tube types, ammonia testing is particularly suited to the conditions provided by the Dark Green tube. Blood cultures and TSR tests typically require different collections and additives, which do not align with the use of the Dark Green tube.