Identify the correct order of draw for blood collection tubes.

The order of draw is critically important in phlebotomy to prevent cross-contamination of additives from one tube to another, which can affect test results. The correct sequence starts with blood cultures to minimize the risk of contamination from other tubes. Following blood cultures, light blue tubes are collected because they contain sodium citrate, which is used for coagulation tests; it is essential to ensure that any potential contamination from other additives is avoided.

Next comes the red tube, which is a plain tube used for serum tests. After red tubes, the gold tube, which contains a gel separator or clot activator, is typically used for serological tests that require serum. The green tube, containing heparin for plasma tests, follows next. This is then followed by the lavender tube, which contains EDTA for hematological tests, and finally, the gray tube, which usually contains additives like fluoride for glucose testing.

Each step in this order has been established to maintain the integrity of the specimens collected and ensure accurate lab results, making this order the standard practice in phlebotomy.