The Art of Phlebotomy: Why Is the Order of Draw So Important?

According to the National Cancer Institute, phlebotomy is defined as "a procedure in which a needle is used to take blood from a vein, usually for laboratory testing." However, phlebotomy involves more than just simply sticking a needle in a vein and drawing blood. In order to become a successful phlebotomist, one must realize that the art of phlebotomy involves utilizing the proper equipment, technique, and procedures in order to collect suitable specimens for testing. Proper collection of blood samples is highly crucial in preserving the integrity of the specimen as well as the accuracy of results. Accurate results ensure that the patient receives the proper care in a timely and efficient manner. A phlebotomist (or any medical professional who is tasked with collecting blood samples from patients) must remember several key principles regarding blood collection. One of these principles is what's known as "the order of draw." At first glance, the average person may think that the order of draw is merely an optional suggestion. Many are not even aware that an order of draw exists or see the importance of adhering to it. Nevertheless, the order of draw has an important place in phlebotomy and was established to improve the quality of human blood specimens as well as the accuracy of test results. This article will answer the following questions: 1) what is the order of draw?, 2) what are the blood collection tubes and their additives/assays?, and 3) why is it important to follow the order of draw?