An Overview of Anesthetics

Anesthetic use has been around for thousands of years, with the first recorded use occurring during the 'pre-history' era. Herbal anesthetics were used in prehistoric times, with the Sumerian Empire being the first to cultivate them. Opium poppies were introduced to India and China in 330 BC and 600 to 1200 AD, respectively. Other'solanum' plant species, including mandrake, henbane, and several datura species, were used as anesthetics in Europe, Asia, and the Americas. Morphine was discovered in 1804, but was not widely used for nearly fifty years.

Anesthetic standardization was achieved prior to the nineteenth century by categorizing anesthetics according to the location in which they were grown. Diacetylmorphine, also known as heroin, was developed in 1874 as a morphine derivative. In 1898, Bayer marketed heroin, which was nearly twice as potent as morphine. Inhalant anesthetics were historically used by Muslim anesthesiologists, and their use was well known throughout the Islamic Empire. Carbon dioxide and nitrous oxide were both used in experimental surgical procedures during the nineteenth century.

Diethyl ether, an inhalant anesthetic, was first synthesized in 1540 by German physician Valerius Cordus. In the modern era, there are two types of modern anesthetics: general and local. Local anesthetics work by preventing nerve impulse transmission in the area where the anesthetic is administered, while general anesthetics are more akin to nitrous oxide in their mode of administration.

For thousands of years, anesthetics have been used. In fact, the first recorded use of anesthetics occurred during the 'pre-history' era, which predated written text.

Herbal Anesthetics' Early Applications

Herbal anesthetics were used in prehistoric times. Opium poppies have been harvested as early as 4200 BC, with the Sumerian Empire being the first to cultivate them. The first documented use of opium-based anesthetics was in 1500 BC, and by 1100 BC, civilizations in Cyprus and other locations were farming and harvesting the plants.

Opium poppies were introduced to India and China, respectively, in 330 BC and 600 to 1200 AD. Other types of herbal anesthetics were also in use in China at the time. Hua Tuo, a Chinese physician, is known to have used a cannabis-derived anesthetic to perform abdominal surgery in the second century.

Several other'solanum' plant species, including mandrake, henbane, and several datura species, were used as anesthetics in Europe, Asia, and the Americas. Each of these has a strong tropane alkaloid. Opium and solanum-containing plants were used by prominent figures such as Hippocrates and Pliny the Elder during the classical Greek and Roman eras. The leaves of the coca plant (from which cocaine is derived) were widely used as an anesthetic in the Americas. Incan shamans used this method by chewing coca leaves and then spitting the leaves into wounds to administer a local anesthetic.

These types of herbal anesthetics were widely used for centuries, but they were not without drawbacks. One of the most difficult aspects of using herbal anesthetics was determining the proper dosage—too little had no effect, and too much often killed the patient. Anesthetic standardization was difficult, but it was accomplished to some extent prior to the nineteenth century by categorizing anesthetics according to the location in which anesthetic plants were grown.

Morphine's Discoverion

Friedrich Wilhelm, a German pharmacist, extracted morphine from the opium poppy in 1804, and named the compound morphium after the Greek god of sleep and dreams. Morphine, on the other hand, was not widely used for nearly fifty years. The hypodermic needle was invented in 1853, and the use of morphine increased dramatically as a result of this new method of administration. Morphine was widely used as an anesthetic at the time.

Diacetylmorphine, also known as heroin, was developed in 1874 as a morphine derivative. Beginning in 1898, Bayer marketed heroin, which was nearly twice as potent as morphine. However, due to the highly addictive nature of these substances, possession of morphine, heroin, and cocaine without a prescription was outlawed in the United States only 16 years later, in 1914.

Inhalant Anesthetics Development

Oral and inhalant anesthetics were historically used by Muslim anesthesiologists, and their use was well known throughout the Islamic Empire. Several hundred surgical procedures were carried out using sponges soaked in narcotic preparations and placed over the patient's face.

In the nineteenth century, one of the main keys to performing successful surgery in the Western world was the development of inhalant anesthetics, along with the use of sterile surgical techniques developed by Joseph Lister.

Carbon dioxide and nitrous oxide were both used in experimental surgical procedures during the nineteenth century. While carbon dioxide was never widely used as an anesthetic, nitrous oxide became extremely popular.

Humphry Davy, a British chemist, discovered nitrous oxide's anesthetic properties in a paper published in 1800. However, nitrous oxide did not become widely used until several decades later, in the 1840s. In 1846, American dentist William Thomas Green Morton performed one of the first successful uses of the gas for painless tooth extraction.

Diethyl ether, an inhalant anesthetic, was also used for tooth extraction during the same decade. Diethyl ether was first synthesized in 1540 by German physician Valerius Cordus; however, it was not until the 1840s that the first public demonstration of its use occurred. Chloroform had been developed a decade earlier, in the 1830s. This became more popular in the United Kingdom, but the dangers of both ether and chloroform were well-known.

Anesthetics in the Modern Era

There are two types of modern anesthetics: general and local. Lidocaine and procaine are examples of local anesthetics. These work by preventing nerve impulse transmission in the area where the anesthetic is administered. General anesthetics, on the other hand, are more akin to nitrous oxide in their mode of administration, and this inhalant anesthetic is still in use. Inhalation anesthetics are typically fluorochemicals (isoflurane, sevoflurane, and desflurane) with significantly lower flammability than diethyl ether, making them much safer to use in the operating room.