In the correct order of draw for blood collection, which color tube comes last?

In the order of draw for blood collection, anticoagulant tubes are typically drawn before serum tubes in order to avoid cross-contamination of additives. The green tube, which contains heparin as an anticoagulant, is used for plasma determinations and should be drawn earlier in the sequence to prevent any potential interference with the tests being performed.

The last tube in the correct order of draw is usually the red tube. This tube is used for serum collection and does not contain any additives that could affect test results. It is essential to collect serum tubes after those containing additives to ensure that the serum is free of anticoagulants or other substances that might be present in the earlier tubes.

Therefore, in this context, the red tube being drawn last is aligned with standard venipuncture protocol to maintain the integrity of the samples collected.