Green Top Tube (Lithium Heparin) – (Use for Routine Chemistry, Ionized Calcium)
- Allow the tube to fill until blood flow ceases.
- Immediately after drawing, gently invert the tube 5-10 times to activate the anticoagulant and prevent clotting.
- Use the bar code label with the patient’s name and ID to identify the specimen.
- Centrifuge 20 minutes for fixed angle, 15 minutes for swing bucket centrifuges. Centrifuge immediately after collection, but no more than 2 hours after collection.
- Check for a good gel separation. If separation is not complete, transfer the clear portion of the plasma into another labeled Green Top Tube and recentrifuge. Never recentrifuge the same tube.
- Refrigerate at 2°- 8° C.