What is the first step in the order of draw for phlebotomy?

The first step in the order of draw for phlebotomy is to collect blood cultures. This step is crucial because blood cultures are drawn to detect the presence of bacteria or fungi in the bloodstream. To ensure the accuracy of these tests, it is important to avoid contamination from other tubes or materials used in the collection process. Blood cultures require a sterile environment and are sensitive to the presence of any microorganisms that may originate from skin flora or other sources. Therefore, they must be collected before any other types of blood specimens to maintain the integrity of the sample.

This practice aligns with the principle of using a specific order of draw to prevent cross-contamination between different tube additives, which can potentially affect the results of various tests. By prioritizing blood cultures, phlebotomists can ensure that the most critical and sensitive tests are performed correctly. Other types of tubes, such as serum tubes or anticoagulant tubes, are collected afterward in a specific sequence to avoid contamination and ensure accurate test results.