Since antiquity there have been many myths and beliefs about the characteristics of the blood. From the Middle Ages, and until the early part of the Industrial Age, people believed that the blood carries the evil humors of disease. With the discovery of how blood works in the body and the benefits of modern medicine circulating, emerged a more scientific description of blood. Blood ceased to be a mysterious medium and became a vital biological fluid that provides valuable information about human health and disease. Because of this, there is literally one Blood-Testing Center in every major city in the world today. Currently blood tests are essential in healthcare, and they are generally carried out in one of three different samples: whole blood, plasma or serum. There are numerous criteria that determine which is the most suitable sample for the testing in particular. But before the bloodwork gets to the lab, it must leave the body. And that is where many people have issues. Even though it is a necessary part of medicine, many have a fear of phlebotomy (the art of drawing blood). Below is a step by step procedure that the phlebotomist will take.
- Phlebotomy is the study of a sample of blood drawn, usually from a vein in the arm and is taken to the laboratory for analysis.
- The puncture site is then cleaned with antiseptic, and a tourniquet (or rubber band) is placed on the arm. This causes the vein below the tourniquet to distend (fill with blood). Then a needle is inserted into a vein of the phlebotomist’s choice and blood is collected in a syringe or airtight vial. During the procedure, the tourniquet is removed to restore circulation. Once the blood is taken, the needle is withdrawn and the punctured site will be covered with gauze and tape to ensure bleeding has stopped.
Preparation Preparation may vary depending on the specific test. In fact, many do not require preparation, but your local Blood-Testing Center does offer a number of recommendations:
- Adults and children: A 3-hour fasting is sufficient for most tests. However, if you can, fasting for 8-hours to have assurances that nothing you eat or drink will not affect any test they perform is optimal.
- Babies should fast for 3-4 hours and never longer.
- Do not smoke before blood extraction.