Green Top Tube (Lithium Heparin) – (Use for Routine Chemistry, Ionized Calcium)

  1. Allow the tube to fill until blood flow ceases.
  2. Immediately after drawing, gently invert the tube 5-10 times to activate the anticoagulant and prevent clotting.
  3. Use the bar code label with the patient’s name and ID to identify the specimen.
  4. Centrifuge 20 minutes for fixed angle, 15 minutes for swing bucket centrifuges. Centrifuge immediately after collection, but no more than 2 hours after collection.
  5. 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.
  6. Refrigerate at 2°- 8° C.