A History of Bloodwork: Part I
- V. A. Cyr
- Sep 25, 2024
- 5 min read
Updated: Jan 20
We have discussed parts of the nursing assessment (Auscultation, Palpation & Percussion) and the vital signs (Blood Pressure, Pulse & Pulse Oximetry, Temperature, and Respirations). Now, we will discuss diagnostic methods, starting with a two-part examination of Bloodwork. In Part I of this topic, we will discuss the blood and the history of blood testing. In Part II, we will learn of the uses of bloodwork in medicine. So, how did bloodletting become common practice? And how did we go from bloodletting to modern practices of phlebotomy?
Definitions
Bloodwork has many terms that are all used interchangeably: blood draw, venipuncture, and phlebotomy. All these mean a procedure in which blood is drawn from the veins. Blood can be taken from any vein (or artery in some cases), but it is most popular to take it at the arm’s antecubital fossa (brachial vein) or the hand’s dorsal side (back). These are also common areas for intravenous (IV) catheter insertion.
This is a diagram of the popular venipuncture sites on the arm and hand (Nurse Key, 2020).
Components of Blood
Blood comprises three main components: red blood cells (RBCs), white blood cells (WBCs, including platelets), and plasma. RBCs or erythrocytes transport oxygen from the lungs to the body’s tissues. WBCs or leukocytes are part of the immune response and fight infection. WBCs comprise of neutrophils (digest bacteria), monocytes (macrophages), and lymphocytes (B and T cells) (Dean, 2005). Platelets act by clotting the blood to prevent exsanguination (bleeding out).
These are estimates of the components of the blood (Shalom Education, n.d.).
Blood Types
There are four types of blood (ABO): A, B, AB, and O (initially called type C). Testing must be done to determine which antigens and antibodies are present in the blood.
Type A has type A-antigens on the RBC and anti-B antibodies in the plasma.
Type B has type B-antigens on the RBC and anti-A antibodies in the plasma.
Type AB has both type A and B-antigens on the RBC and no antibodies in the plasma.
Type O has no antigens on the RBC and anti-A and anti-B antibodies in the plasma.
Here is a chart of the antigens and antibodies found in each blood type (Medic Tests, 2024).
The Rh (rhesus) factor is a protein in the RBCs. Any blood type can be Rh-positive (+) or Rh-negative (-) (e.g., A+, B-, AB+, O-, etc.). O-negative is the universal donor and can be given to any patient regardless of blood type. Although, because O- can be given to everyone, those with O- can only be given O- blood. If there is not enough time to do a type and cross-matching test at the laboratory and someone needs blood immediately (transfusion), they can be given O-negative safely. On the other hand, AB+ is the universal recipient. If a person has AB+ blood, they can be given any type of blood. While this is good, those who donate AB+ blood can only be given to AB+ patients. The antibodies in the plasma will attack anything that is not like itself (e.g., in type A, the antibodies will attack type B blood). In this “attack” response, the body starts to destroy all RBCs that are invaders. This will cause large-scale hemolysis (killing of RBCs) and can cause major negative adverse reactions. This is why verifying (and re-verifying) someone’s blood type is important before giving them a transfusion! This type of reation can also occur in pregnant women when the fetus’s blood type (ABO+) does not match with the mother’s (Rh-).
This chart breaks down which blood types can be given to patients with specific blood types (Canadian Blood Services, 2024).
Origins
The Greek physician Hippocrates believed in the theory of humours, which states that the body has four fluids that must be balanced to be mentally and physically healthy (Raikar, 2024). These four “humours” are blood (sanguine), phlegm (phlegmatic), yellow bile (choleric), and black bile (melancholic). To balance these fluids, the practice of bloodletting began. Bloodletting is the technique of removing the blood (and “diseases”) from the body.
Here is a depiction of the four humours in realtion to the sexes (male and female), zodiac sign, and other symbols (e.g., air, earth, wind, fire) (Moorehouse, n.d.).
Bloodletting gained popularity in the 2nd Century when Galen insisted that blood was the most essential fluid and must be removed to balance the humours (Raikar, 2024). Galen advocated for leeching (bloodletting using leeches) as a treatment method (Raikar, 2024).
Bloodletting became the standard treatment method in the Middle Ages for all conditions, like epilepsy, smallpox, and the plague. Physicians, professional leechers, and priests performed bloodletting with a small balded tool called a fleam. Once priests were no longer allowed to practice this method, barber-surgeons took on the practice. The barber shop pole symbolizes the treatments they could offer (red symbolizing bloodletting, white for tooth extractions, and blue for shaving services) (Raikar, 2024).
In the 17th and 18th Centuries, physicians still advocated for bloodletting. In England, William Harvey first described the circulatory system and found bloodletting helpful in treating most diseases (Raikar, 2024). In the United States, Benjamin Rush said that all diseases are “fevers” and can be remedied with bloodletting (Raikar, 2024). Edward Jenner, the pioneer of the smallpox vaccination, used lancets for bloodletting and applied vaccines into the wounds (Raikar, 2024).
Many famous people during history have had bloodletting done to various degrees of “success.” In 1685, King Charles II was treated with bloodletting after a seizure, possibly hastening his death (Raikar, 2024). Marie-Antoinette had it done when she fainted while giving birth to her first child in 1778 (Raikar, 2024). George Washington requested it to aid his throat infection in 1799 and died after four rounds of bloodletting (Raikar, 2024).
The modern-day method of phlebotomy is not used as a form of bloodletting. It is primary for diagnostic testing and blood transfusions. Bloodwork is done by inserting a needle into the vein, and transfusions are done using an intravenous (IV) catheter.
In 1901, Karl Ladnsetiner discovered the blood types (A, B, AB, and C, now type O) and was also credited with discovering the Rh factor (Optimists, 2023).
Disease testing, such as testing for syphilis and rubella (Optimists, 2023), became more popular in the 1930s and 1940s. The first testing for Hepatitis B was done in 1971, while the first test for HIV (human immunodeficiency virus) was not done until 1985 (Optimists, 2023). This was done to diagnose patients, and screen donated blood to ensure no diseases were being transferred to patients needing blood transfusions. We will further discuss diagnosing and testing in Part II.
Timeline Throughout History: Bloodletting Tools
The uses in medicine and laboratory blood tests will be examined and discussed in A History of Bloodwork: Part II!
– V. A. Cyr
References
Allied Medical. (n.d.). Nexiva Closed IV Catheter System With Single Port [Image]. https://www.alliedmedical.com/store/pc/Nexiva-Closed-IV-Catheter-System-With-Single-Port-p2950.htm
Arbittier, D. (2024). Bloodletting Instruments and Methods [Images]. Journal of Antiques & Collectibles. https://journalofantiques.com/features/bloodletting-instruments-methods/
Bridgeman Images. (n.d.). Fol.19r Bloodletting, from 'Traite de Medecine' by Aldebrande de Florence, 1356 (vellum) [Image]. https://www.bridgemanimages.com/en-US/french-school/fol-19r-bloodletting-from-traite-de-medecine-by-aldebrande-de-florence-1356-vellum/vellum/asset/223820
Canadian Blood Services. (2024). Blood type chart [Image]. https://www.blood.ca/en/blood/donating-blood/what-my-blood-type
Dean, L. (2005). Chapter 1, Blood and the cells it contains. In L. Dean’s Blood Groups and Red Cell Antigens.
Moorehouse, D. (n.d.). Theory of the Four Humours [Image]. https://schoolshistory.org.uk/topics/medicine-through-time/medicine-in-ancient-greece/theory-of-the-four-humours/#google_vignette
National Center for Biotechnology Information. https://www.ncbi.nlm.nih.gov/books/NBK2263/
Nurse Key. (2020). Figure 18-1. Veins in the upper extremities most commonly used for venipuncture sites [Image]. https://nursekey.com/blood-drawing-from-peripheral-sites-venipuncture/
Optimists. (2023). Evolution of Blood Tests. Kepler Techno Private Ltd. https://optimists.in/health-hub/evolution-of-blood-tests/
Raikar, S. P. (2024). Bloodletting. Britanica. https://www.britannica.com/science/bloodletting
Shalom Education. (n.d.). Red blood cells, white blood cells and platelets are all suspended in blood plasma [Image]. https://www.shalom-education.com/courses/gcse-biology/lessons/transport-systems/topic/the-composition-of-blood/
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