The term "anesthesia" refers to insensibility to pain. Efforts to ease or eliminate pain are as old as pain itself. The early Chinese used both acupuncture and Indian hemp to dull the perception of pain. Ancient Hindu civilizations used henbane and wine as well as hemp. The Romans experimented with mechanical methods of producing unconsciousness: pressing on the carotid artery in the neck or controlled bleeding from arteries in the wrist. In the first century a.d. the Greek physician Dioscorides (40-90 a.d.) described the use of wine of mandragora (mandrake) to produce a deep sleep in surgical patients and used the Greek "anesthesia" to describe the phenomenon. Pliny (23-79 a.d.) also mentioned the use of mandragora. The Greek poet Homer referred to the pain-killing effects of nepenthe, and the Greek hisotrian Herodotus wrote of hemp fumes. Alcohol--wine and brandy--was widely used by early peoples for its numbing effects. So was the opium poppy. Its seeds have been found in prehistoric Swiss lake dwellings, and it had found its way to Egypt by the second century a.d. Opium remained in use and was praised by Avicenna (980-1037) in the eleventh century as the most powerful of stupor-producing substances. It was promoted for many medical uses by Thomas Sydenham in the 1600s.
Early Arab writings mention anesthesia by inhalation. This idea was the basis of the "soporific sponge" ("sleep sponge"), introduced by the Salerno school of medicine in the late twelfth century and by Ugo Borgognoni (Hugh of Lucca) in the thirteenth century. The sponge was promoted and described by Hugh's son and fellow surgeon, Theodoric Borgognoni (1205-1298; Theodoric of Bologna). In this anesthetic method, a sponge was soaked in a dissolved solution of opium, mandragora, hemlock juice, and other substances. The sponge was then dried and stored; just before surgery the sponge was moistened and then held under the patient's nose. When all went well, the fumes rendered the patient unconscious.
Mechanical methods of inducing anesthetic effects were also used. Guy de Chauliac (1300-1368) employed compression of the nerve trunk in the 1300s, and Ambroise Paré did the same in the 1500s. Bleeding patients into unconsciousness, the ancient Roman practice, was recommended in 1777 by Alexander Munro II of Edinburgh, Scotland, and put into practice around 1800 by Philip Syng Physick (1768-1837) of Philadelphia.
The modern era of anesthesia began in the late eighteenth century when chemists began to investigate the nature of many substances. Joseph Priestley discovered nitrous oxide in 1772, and in 1800 Humphry Davy discovered the gas's anesthetic properties when inhaled. Davy' s student, Michael Faraday, showed in 1818 that inhalation of ether had the same effect. Henry Hill Hickman (1800-1830) experimented with both carbon dioxide and nitrous oxide on animals to carry out painless surgery in the early 1820s.
The anesthetic effects of these substances were first put to practical use by several American dentists and doctors. Georgia physician Crawford Long (1815-1878) performed the first operation under ether anesthesia in 1842. Two years later, a Hartford, Connecticut, dentist named Horace Wells (1815-1848) used inhaled nitrous oxide to extract a tooth painlessly. Boston dentist William T. G. Morton (1819-1868) arranged the first public demonstration of ether-anesthetized surgery in 1846. News of the technique leaped across the Atlantic; in London, two months after Morton's surgery, Dr. Robert Liston (1794-1847) performed an amputation using ether anesthetic. The technique soon spread worldwide.
After Morton's demonstration, the question arose of what to call the new phenomenon. Oliver Wendell Holmes suggested the term anesthesia. Although Holmes is often credited with inventing the term, in fact it had appeared in Bailey 's 1721 Dictionary Britannicum and had been mentioned as long ago as the first century a.d.
Scottish obstetrician James Young Simpson (1811-1870) introduced chloroform to childbirth (after first experimenting with ether) in 1847. Queen Victoria's use of chloroform for her own labors in 1853 and 1857 firmly established the procedure as standard in childbirth. Dr. John Snow (1813-1858), who administered the chloroform to the queen, became the foremost authority on anesthesia and is recognized today as the world's first professional anesthetist, a pioneer of a new medical specialty. Local anesthesia also became important, especially after the invention of the hypodermic syringe by Charles Gabriel Pravaz (1791-1853) in 1853. Alexander Wood (1817-1884) of Edinburgh used the syringe to inject pain-relieving morphine soon after. Dr. B. W. Richardson (1828-1896) of Glasgow, Scotland, introduced ether spray for freezing tissue in 1866. Carl Koller (1857-1944) demonstrated the use of cocaine as a local anesthetic in 1884. Baltimore surgeon William Halsted developed the technique of conduction anesthesia by blocking nerve impulses with injections of cocaine. The addictive cocaine was replaced by synthetics beginning with Novocain in 1904. Intratracheal anesthesia --introducing an anesthetic through a tube in the trachea--was pioneered by New York surgeon George Fell (1850-1918) and perfected in 1909 by Samuel Meltzer and John Auer of the Rockefeller Institute. Spinal anesthesia to numb the lower half of the body was experimented with in 1885 by New York neurologist Leonard Corning (1855-1923) when he injected a cocaine solution into the spinal region. The German doctor August Bier (1861-1949) refined the technique in 1898, and Rudolph Matas (1860-1957) of New Orleans introduced it to the United States in 1899. By the 1920s the use of spinal anesthesia was widespread in the United States. Intravenous anesthesia was first attempted by Robert Boyle and the renowned architect Christopher Wren (1632-1723) around 1659. An injected warm solution of opium in sherry stupified their subject, a dog. Johann Major of Germany tried the same technique in a human subject in 1667. The idea, however, was abandoned until about 1874, when Pierre Oré used chloral hydrate intravenously on a dog and then, in 1875, on a human patient. Once barbiturates were discovered in the early 1900s, and especially after improved substances were developed in the 1920s, the use of intravenous anesthetics became firmly established.
Early in the 1900s the surgeons Harvey Cushing (1869-1939) and George Crile (1864-1943) contributed to the safety of anesthesia by promoting monitoring of the patient's blood pressure during operations. Crile and Cushing also combined local or regional with general anesthetics, dosing surgical patients with morphine and scopolamine or local infiltration anesthesia to block nerve impulses that can reach the brain even during deep ether anesthesia. Relaxants such as atropine and curare also came into use to lessen the involuntary resistance of a patient to the application of anesthetics such as ether or the spinal needle.
Today's anesthetist is a highly trained specialist who administers several anesthetics at the same time and uses sophisticated equipment to monitor a patient's blood pressure; rate of respiration; heartbeat; and blood levels of oxygen, carbon dioxide, and anesthetic vapors. Although current anesthetics are highly effective, they do pose a certain amount of risk. As a result, continued research focuses on developing safer and more effective anesthetics. For example, researchers at the University of Pennsylvania Medical Center have demonstrated that giving an anesthetic to patients prior to surgery (called pre- emptive analgesia) appears successful in stopping post-surgical pain before it begins. Researchers are also using gene therapy in an animal model which may lead to new discoveries about the brain's reaction to anesthesia. By using a virus-mediated gene that appears to affect the chemical receptors in lab animals' brains, investigators have developed the ability to study the pharmacological responses of genetically altered receptors. With this approach, it may be possible to learn more about how brain receptors react to general anesthesia, which, in turn, could lead to improved and new approaches to anesthesia.
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