Tuesday, October 26, 2010

Life lines 10


I like to go back to original sources when I write my books on the history of science. It’s not just a matter of getting the names and dates right. When you go back the past leaps out of a page or document and surprises you with novelty. While working on the history of blood groups for a book on the history of human genetics, I came across a reference that the first blood transfusion in a human was carried out in 1667 and the donor was a sheep. My first thought was that this was a long time ago and the patient must have died from the transfusion. My second thought (on the use of the sheep) was that the sheep was docile and convenient. I looked up the cited entry in Samuel Pepys’s diary and learned that the patient was a 32 year old Cambridge graduate, Arthur Coga, who was a Latin scholar and whose minister thought him on the verge of lunacy. He consulted a physician who recommended cooling his brain with a blood transfusion. In those days the brain was believed to be the place where the blood was cooled, a logical inference for fevered brains causing delirium and for violent tempered people who are still called hot blooded.

Coga was asked what type of blood he wanted as a coolant and he said he wanted a lamb’s blood because Jesus is the Lamb of God (Agnus Dei) and if he couldn’t have the Savior’s blood, the closest thing in purity must be that of a lamb. He was given about 12 ounces of blood by canula and survived. Pepys recounted Coga’s conversation at the Royal Society a week after his transfusion and reported Coga as lucid in his conversation. Coga also told his questioners that he was looking forward to a second transfusion of sheep blood.

Transfusions of animal blood to humans that same year in France led to several deaths and there was a ban on human blood transfusions in most countries until Karl Landsteiner in 1900 identified specific blood types in humans (initially he called them I, II, and III). They were renamed A, B, and O a few years later and the rarer AB group was found by two of Landsteiner’s students. Surprisingly it took almost 20 years to do effective transfusions because blood tends to clot and anti-clotting chemicals were not found until 1914. Blood banks did not come into existence until the early 1930s. I do not know if Coga had that second transfusion. It is likely, if he did, that it would have killed him from the shock reaction of his immune system. I also do not know how long the placebo effect lasted from his first transfusion.

But as a contemporary scientist I would never have imagined that a sheep’s blood was the source for a first human blood transfusion. Nor would I have imagined that the transfusion was made for religious reasons. Nor would I have imagined that the transfusion was given to treat a mental illness rather than to replace a loss of blood. The pleasure of doing history of science is that it reveals how different were the assumptions about life, science, and values when we go back in time. It also serves as a reinforcement of healthy skepticism so that we resist the temptation to interpret the past through the expectations of the present.

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