Blood transfusion, the process of transferring blood or blood components from one person into the bloodstream of another, is a life-saving medical procedure today. This practice is commonplace in modern hospitals, making it easy to forget the long, often dangerous history that led to its safety. Implementing the foundational idea of replacing lost blood practically and safely required centuries of failed experiments and a monumental scientific discovery. Determining when the first transfusion was performed depends on distinguishing between conceptual attempts and a documented landmark event.
Early Attempts and Failures
The concept of circulatory blood flow was not scientifically established until English physician William Harvey published his work in 1628, a necessary precursor to transfusion. Once circulation was understood, 17th-century physicians began experimenting with transferring blood between living creatures. The earliest documented successful transfusions were performed between animals, notably by Richard Lower in England in 1665.
Lower demonstrated that a dog could be kept alive by transfusing blood from another dog using quills and small silver tubes. These experiments quickly progressed to xenotransfusion, the transfer of blood between different species. Richard Lower was among those who performed animal-to-human transfusions in England in 1667, typically using sheep’s blood on individuals who were mentally ill.
The fundamental failure of these attempts stemmed from the profound biological incompatibility between animal and human blood. The transfused foreign blood would trigger a severe, often lethal immune reaction in the recipient, an effect not understood at the time. This procedure remained a dangerous gamble for decades, resulting in high mortality rates that stalled its adoption in mainstream medicine.
The Documented Landmark Transfusion
The event most often cited as the first documented blood transfusion into a human occurred in France on June 15, 1667, performed by physician Jean-Baptiste Denys. Denys, the personal physician to King Louis XIV, transfused approximately 12 ounces of blood from a lamb into a 15-year-old boy. The young patient had been severely weakened by excessive bloodletting, a common but harmful medical practice of the era.
The boy survived the procedure and appeared to recover quickly, likely because only a small amount of the foreign blood was successfully transferred. Denys performed a few other transfusions with initial success, including one on a laborer, which led to a brief period of excitement. The physician reasoned that blood from a gentle, docile animal might be purer and better for the human recipient.
This early success was quickly overshadowed by subsequent failures. Denys performed a third transfusion on a Swedish baron who died shortly after the second attempt. The death of another patient, Antoine Mauroy, after a series of calf blood transfusions, resulted in Denys being cleared of murder charges but led to a severe legal backlash. The French Parliament formally banned the practice of blood transfusion in 1670, with the English Parliament soon following suit. This official prohibition, coupled with the unpredictable outcomes, effectively halted transfusion medicine for over 150 years.
The Discovery That Made Transfusions Safe
For nearly two centuries after the 1670 ban, transfusions were rarely attempted and remained highly risky, even when using human-to-human blood. Physicians lacked the scientific explanation for why blood sometimes mixed and sometimes did not. The scientific breakthrough that finally transformed transfusion from a perilous experiment into a dependable medical treatment occurred at the dawn of the 20th century. In 1900, Austrian physician Karl Landsteiner discovered the existence of human blood groups.
Landsteiner identified that human red blood cells possessed different antigens, initially categorized as types A, B, and C (later renamed O). He demonstrated that mixing the blood serum of one person with the red blood cells of another could cause the cells to clump together, a process known as agglutination. This clumping was the lethal reaction that had plagued earlier attempts. Landsteiner’s work established the fundamental principle of blood compatibility: a patient must receive blood that does not contain antigens their own immune system will attack.
The discovery of the ABO system provided the basis for “cross-matching,” allowing doctors to test donor and recipient blood for compatibility before transfusion. By 1907, the first successful blood transfusion guided by Landsteiner’s blood typing was performed in New York. This scientific understanding, for which Landsteiner received the Nobel Prize in 1930, laid the groundwork for safe, modern transfusion medicine.