Lithium heparin glass tubes are a type of blood collection tube used in medical settings for the collection of blood samples. These tubes contain lithium heparin, an anticoagulant, which prevents blood from clotting by inhibiting the action of thrombin and other clotting factors.When blood is collected into a lithium heparin tube, the heparin prevents clotting, allowing the blood to remain in a liquid state. It's also crucial to label the tubes accurately with patient identification information to prevent sample mix-ups.