from bleeding to blood transfusions

From Antiquity to the 17^e century, bloodletting was the most widespread medical act, because all the miracles were attributed to it. At the same time, transfusion, which has nothing to do with bleeding, developed at the same time. Denis Goulet, visiting professor at the Faculty of Medicine of the University of Montreal and specialist in the history of medicine, tells the evolution of these practices.

“We conceived of health as being the balance of the four humours: blood, bile, atrabile and phlegm. And any form of imbalance of these humors was supposed to cause the disease, explains Denis Goulet. Moods were linked to the temperaments of individuals. Incidentally, the colloquialisms “to be in a good mood or in a bad mood”, and “to get bad blood” come from this bloodletting theory.

The surgeons of the time incised the skin in several places, especially in the feet, legs, forearms and sometimes in the ears. This practice remained in place for a long time, due to the refusal to dissect the bodies, which would have allowed researchers to better understand the function of the organs.

In 1628, the Briton William Harvey discovered the principle of blood circulation. Paradoxically, some doctors still prescribe bloodletting, since this principle proves that the heart is a pump. At the same time, anatomical dissections spread. At 18^e century, the theory of humours is undermined. The bleeding disappeared from the following century.

Blood transfusion develops in parallel to the 17^e century. The first transfusion is done with sheep’s blood and is a success, but the other operations from the animal to the man cause deaths and are abandoned.

The transfusion reappeared when Karl Landsteiner discovered blood groups A, B and 0 in 1900, and AB in 1901. Goulet.

Shortly following, the First World War was an ideal testing ground for medicine. “Advances, in a more or less empirical way, will make it possible to improve emergency surgery, in particular, and will make it possible to improve blood transfusion”, summarizes our guest. However, the rhesus factor (positive and negative) was not discovered until 1939.

Also during this program, Denis Goulet recalls the contaminated blood scandal in the 1980s, and he explains why bleeding still exists, but in very rare cases.