Bloodwork or blood work is a type of medical testing which is performed on a blood sample. In bloodwork, a medical technician analyzes a sample of blood to look for key indicators which can provide clues about the patient's health. Bloodwork is a routine part of many medical procedures, from a diagnostic workup to an evaluation of a candidate for surgery, and many people experience blood draws for bloodwork at some point in their lives.
Samples of blood are classically taken intravenously, by inserting a needle into one of the veins on the inside of the elbow to access a sample of blood. Sometimes, bloodwork can be accomplished with a smaller sample obtained from a fingerstick blood test. In other instances, arterial blood may be required for bloodwork, depending on the patient and the circumstances. In all cases, a nurse, phlebotomist, or doctor can take the blood sample, observing careful procedures to maintain the integrity of the blood sample.
Doctors can order bloodwork to look for a variety of things. In a full blood panel, the technician who does the analysis provides a full discussion of the various components in the patient's blood chemistry, including liver enzymes, electrolytes, trace hormones, and the levels of red and white blood cells. Full panels tend to be expensive, because they require a variety of tests on the blood sample. The full panel often comes with information about average ranges of various substances in the blood which can be compared against the patient's results, and the technician may offer additional commentary about the implications of the results.
In other instances, a doctor may request that the technician look for something in particular, such as traces of the hormones associated with pregnancy, or glucose levels after a fasting test to check for diabetes. The cost of this type of bloodwork can vary, depending on what the technician is looking for. Liver enzyme panels, for example, can be quite costly, while pregnancy tests are often inexpensive.
Some doctors recommend annual bloodwork to check for signs of underlying medical conditions or emerging diseases which can be caught early. Annual bloodwork is especially strongly recommended for animals, since they are not able to communicate about symptoms. Bloodwork is also routinely requested before surgery, as part of an evaluation to determine whether or not the patient is fit for surgery, and it is also used in doping tests to determine whether or not someone has been using banned substances.