William Harvey
Born in Folkestone, Eng.,William Harvey studied at Cambridge University and then spent several years at Padua, where he came under the influence of Fabricius. He established a successful medical practice in London and by precise observation and scrupulous reasoning developed his theory of circulation. In 1628 he published his classic book Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus (An Anatomical Exercise Concerning the Motion of the Heart and Blood in Animals (Concerning the Motion of the Heart and Blood), often called De Motu Cordis.
That the book aroused controversy is not surprising. There were still many who adhered to the teaching ofGalen that the blood follows an ebb and flow movement in theblood vessels. Harvey's work was the result of many careful experiments, but few of his critics took the trouble to repeat the experiments, simply arguing in favour of the older view. His second great book, Experiments Concerning Animal Generation, published in 1651, laid the foundation of modern embryology.
Harvey's discovery of the circulation of the blood was a landmark of medical progress; the newexperimental method by which the results were secured was as noteworthy as the work itself. Following the method described by the philosopher Francis Bacon, he drew the truth from experience and not from authority.
There was one gap in Harvey's argument: he was obliged to assume the existence of the capillary vessels that conveyed the blood from the arteries to the veins. This link in the chain of evidence was supplied byMarcello Malpighi of Bologna (who was born in 1628, the year of publication of De Motu Cordis). With a primitive microscope Malpighi saw a network of tiny blood vessels in the lung of a frog. Harvey also failed to show why the blood circulated. After Robert Boyle had shown that air is essential to animal life, it was Richard Lower who traced the interaction between air and the blood. Eventually the importance of oxygen, which was confused for a time by some as phlogiston, was revealed, although it was not until the late 18th century that the great chemist Antoine-Laurent Lavoisier discovered the essential nature of oxygen and clarified its relation to respiration.
Although the compoundmicroscope had been invented slightly earlier, probably in Holland, its development, like that of the telescope, was the work of Galileo. He was the first to insist upon the value of measurement in science and in medicine, thus replacing theory and guesswork with accuracy. The great Dutch microscopist Antonie van Leewenhoek devoted his long life to microscopical studies and was probably the first to see and describe bacteria, reporting his results to the Royal Society of London. In England,Robert Hooke, who was Boyle's assistant and curator to the Royal Society, published his Micrographia in 1665, which discussed and illustrated the microscopic structure of a variety of materials.
Once the principles of military surgery were relearned and applied to modern warfare, instances of death, deformity, and loss of limb were reduced to levels previously unattainable. This was due largely to a thorough reorganization of the surgical services, adapting them to prevailing conditions, so that casualties received the appropriate treatment at the earliest possible moment. Evacuation by air (first used in World War I) helped greatly in this respect. Diagnostic facilities were improved, and progress in anesthesia kept pace with the surgeon's demands. Blood was transfused in adequate—and hitherto unthinkable—quantities, and the blood transfusion service as it is known today came into being.
Surgical specialization and teamwork reached new heights with the creation of units to deal with the special problems of injuries to different parts of the body. But the most revolutionary change was in the approach to wound infections brought about by the use of sulfonamides and (after 1941) of penicillin. The fact that these drugs could never replace meticulous wound surgery was, however, another lesson learned only in the bitter school of experience.
When the war ended, surgeons returned to civilian life feeling that they were at the start of a completely new, exciting era; and indeed they were, for the intense stimulation of the war years had led to developments in many branches of science that could now be applied to surgery. Nevertheless, it must be remembered that these developments merely allowed surgeons to realize the dreams of their fathers and grandfathers; they opened up remarkably few original avenues. The two outstanding phenomena of the 1950s and 1960s—heart surgery and organ transplantation—both originated in a real and practical manner at the turn of the century.
At first, perhaps, the surgeon tried to do too much himself, but before long his failures taught him to share his problems with experts in other fields. This was especially so with respect to difficulties of biomedical engineering and the exploitation of new materials. The relative protection from infection given by antibiotics and chemotherapy allowed the surgeon to become far more adventurous than hitherto in repairing and replacing damaged or worn-out tissues with foreign materials. Much research was still needed to find the best material for a particular purpose and to make sure that it would be acceptable to the body.
Plastics, in their seemingly infinite variety, have come to be used for almost everything from suture material to heart valves; for strengthening the repair of hernias; for replacement of the head of the femur (first done by the French surgeon Jean Judet and his brother Robert-Louis Judet in 1950); for replacement of the lens of the eye after extraction of the natural lens for cataract; for valves to drain fluid from the brain in patients with hydrocephalus; and for many other applications. This is a far cry, indeed, from the unsatisfactory use of celluloid to restore bony defects of the face by the German surgeon Fritz Berndt in the 1890s. Inert metals, such as vitallium, have also found a place in surgery, largely in orthopedics for the repair of fractures and the replacement of joints.
The scope ofsurgery was further expanded by the introduction of the operating microscope. This brought the benefit of magnification particularly to neurosurgery and to ear surgery. In the latter it opened up a whole field of operations on the eardrum and within themidle ear. The principles of these operations were stated in 1951 and 1952 by two German surgeons, Fritz Zöllner and Horst Wullstein; and in 1952 Samuel Rosen of New York mobilized the footplate of the stapes to restore hearing in otosclerosis a procedure attempted by the German Jean Kessel in 1876.
Although surgeons aim to preserve as much of the body as disease permits, they are sometimes forced to take radical measures to save life; when, for instance, cancer affects the pelvic organs. Pelvic exenteration (surgical removal of the pelvic organs and nearby structures) in two stages was devised by Allen Whipple of New York City, in 1935, and in one stage by Alexander Brunschwig, of Chicago, in 1937. Then, in 1960, Charles S. Kennedy, of Detroit, after a long discussion with Brunschwig, put into practice an operation that he had been considering for 12 years: hemicorporectomy—surgical removal of the lower part of the body. The patient died on the 11th day. The first successful hemicorporectomy (at the level between the lowest lumbar vertebra and the sacrum) was performed 18 months later by J. Bradley Aust and Karel B. Absolon, of Minnesota. This operation would never have been possible without all the technical, supportive, and rehabilitative resources of modern medicine.
In 1967 surgery arrived at a climax that made the whole world aware of its medicosurgical responsibilities when the South African surgeonChristian Barnard transplanted the first human heart. Reaction, both medical and lay, contained more than an element of hysteria. Yet, in 1964, James Hardy, of the University of Mississippi, had transplanted a chimpanzee's heart into a man; and in that year two prominent research workers, Richard Lower and Norman E. Shumway, had written: "Perhaps the cardiac surgeon should pause while society becomes accustomed to resurrection of the mythological chimera." Research had been remorselessly leading up to just such an operation ever since Charles Guthrie and Alexis Carrel, at the University of Chicago, perfected the suturing of blood vessels in 1905 and then carried out experiments in the transplantation of many organs, including the heart.
New developments in immunosuppression (the use of drugs to prevent organ rejection) have advanced the field of transplantation enormously. Kidney transplantation is now a routine procedure that is supplemented by dialysis with an artificial kidney (invented by Willem Kolff in wartime Holland) before and after the operation; mortality has been reduced to about 10 percent per year. Rejection of the transplanted heart by the patient's immune system was overcome to some degree in the 1980s with the introduction of the immunosuppressant cyclosporine; records show that many patients have lived for five or more years after the transplant operation.
The complexity of the liver and the unavailability of supplemental therapies such as the artificial kidney have contributed to the slow progress in liver transplantation (first performed in 1963 by Thomas Starzl). An increasing number of patients, especially children, have undergone successful transplantation; however, a substantial number may require retransplantation due to the failure of the first graft.
Lung transplants (first performed by Hardy in 1963) are difficult procedures, and much progress is yet to be made in preventing rejection. A combined heart-lung transplant is still in the experimental stage, but it is being met with increasing success; two-thirds of those receiving transplants are surviving, although complications such as infection are still common. Transplantation of all or part of the pancreas is not completely successful, and further refinements of the procedures (first performed in 1966 by Richard Lillehei) are needed.
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