More than 15 million pints of blood are donated each year in the U.S. to be used in transfusions to over five million patients
So the idea of, like, putting blood into a person was a radical one when it was first attempted three hundred and fifty years ago
and it was also dangerous and really dumb.
The first-ever documented human blood transfusion was conducted using the blood of a sheep. The year was
1667 and the patient was a 15-year-old French boy and somehow he survived. Now,
we gotta note here that, for thousands of years, no one really understood
what blood even was. The Romans and Greeks believed that the body was filled with four basic
substances, or humors, one of which was blood. According to humorism,
the liver turned food into blood which was then distributed via veins to the rest of the organs to feed them.
Hmm. Despite Arabic physicians describing blood circulation as early as 1250 AD, the liver theory pretty much held up until the early 1600's,
when English physician William Harvey, after years of measuring and calculating blood volume and velocity,
said that it was impossible for the liver to produce enough blood based on our food intake. Blood must continuously circulate,
he said, propelled by our beating heart Harvey's discovery set off a half-century of experimentation to learn more about the circulatory system,
often at the expense of dogs who were intravenously injected with various substances,
including ale, wine, and opium. And in 1665, English physician Richard Lower became the first to successfully transfuse blood
from one animal to another,
bleeding, or exsanguinating, a dog near to the point of death and tying the artery off and then using a larger dog as a donor to
refill the little one. Just over two years later, on June 15
1667, French physician Jean-Baptiste
Denys bled three ounces from a 15-year-old boy and transfused nine ounces of blood from a lamb.
Lower would perform a similar procedure on a 32-year-old man less than six months later, using goose quills and silver pipes to carry
the blood. Like the boy, the man survived. Now, these early procedures were not intended as medically necessary
transfusions to replace lost blood; rather, the idea was that the energy and personality
of the blood donor would somehow seep into the recipient. The possibility of altering the mental state of a patient or restoring youth to the aged
was what motivated Lower, Denys, and
others. Denys himself said that the blood of docile animals such as a lamb could exert a calming influence on the troubled and
deranged mind. Given the misconceptions about blood in the 1660's,
we can all agree that Lower and Denys got really lucky with their first animal-to-human blood
transfusions. As modern scientists would later learn, there are many potentially fatal reactions that can occur during a
transfusion; from agglutination, or clumping, if the blood is exposed to even a tiny amount of oxygen; to hemolytic transfusion
reactions, which can cause the recipient's cells to destroy a donor's transfused blood cells releasing substances toxic to the recipient's kidneys.
So, naturally, it wasn't long before early experimenters ran out of luck and
patients began to die. Religious and political leaders, many of whom still believed that blood was the seat of the soul and that
transfusion was blasphemy, quickly banned the practice and it didn't help that even many physicians thought transfusions could cause a change in
species. It would be nearly a hundred and fifty years before a new generation of scientists would pick up the needles that these 17th century crazy
pioneers put down. In
1818, a British doctor named James Blundell performed the first human-to-human blood transfusion, a process that would take over
100 years to achieve regular success. The most important of these improvements was Karl Landsteiner's
classification of ABO blood types at the beginning of the 20th century.
Landsteiner recognized that different types of blood carried different types of antigens, A and/or B,
each of which will set off a potentially deadly immune reaction in patients without that antigen. This knowledge allowed proper matching of donors and
recipients. Scientists nowadays are working on ways to actually create blood from scratch,
but, at the moment, the only way for someone who needs it to get it is to have someone else give it to them. And
with millions in need of transfusions each year, I'll just remind you to donate whenever you're able.
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