Ethers as general anesthetics

Nitrous oxide (N2O), also called laughing gas, was first used as an anesthetic in 1799, and it is still in use today, even though when used alone it does not produce deep anesthesia. The first use of an ether, diethyl ether, to produce deep anesthesia occurred in 1842. In the years that have passed since then, several different ethers, usually with halogen sub- 

Just as alcohols and ethers may be considered as organic derivatives of water, amines may be considered as organic derivatives of ammonia  

Amines are classified as primary, secondary, or tertiary amines. This classification is based on the number of organic groups that are attached to the nitrogen atom  

Notice that this is quite different from the way alcohols and alkyl halides are classified. Isopropylamine, for example, is a primary amine even though its —NH2 group is attached to a secondary carbon atom. It is a primary amine because only one organic group is attached 

Amphetamine (below), a powerful and dangerous stimulant, is a primary amine. Dopamine, an important neurotransmitter whose depletion is associated with Parkinson s disease, is also a primary amine. Nicotine, a toxic compound found in tobacco that makes smoking addictive, has a secondary amine group and a tertiary one. 

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Diethyl ether was at one time used as a surgical anesthetic. The most popular modern anesthetic is halothane (CFsCHBrCI). Unlike diethyl ether, halothane is not flammable. (See The Chemistry of.. Ethers as General Anesthetics, Section 2.7, for more information.)... 

Inhalation is the most common means by which ethers enter the body. The effects of various ethers may include narcosis, irritation of the nose, throat, and mucous membranes, and chronic or acute poisoning. In general, ethers are central nervous system depressants, eg, ethyl ether and vinyl ether are used as general anesthetics. 

Many ethers, including diethyl ether, are effective as general anesthetics. Because simple ethers are quite flammable, their place in medical practice has been taken by highly halogenated nonflammable ethers. Two such general anesthetic agents are isoflurane and enflurane. These compounds are isomeric isoflurane is l-chloro-2,2,2-trifluoroethyl difluoromethyl ether enflurane is 2-chloro-l,l,2-trifluoroethyl difluoromethyl ether. Write the structural formulas of isoflurane and enflurane. 

Cyclopropane was once used as general anesthetic because its vapors, like those of other simple alkanes and cycloalkanes, cause sleepiness and a loss of consciousness. After inhalation into the lungs, cyclopropane goes into the blood. Due to its nonpolar nature, it rapidly leaves the blood and passes through the nonpolar membranes surrounding the central nervous system, where it produces anesthesia. Cyclopropane is no longer used as an anesthetic because it is highly flammable (like ether) and can cause explosions when mixed with air. 

This painting by Robert Hinckley depicts a public demonstration of the use of diethyl ether as an anesthetic at the Massachusetts General Hospital in Boston in the 1840s. 

Halogenated ethers are also routinely used as general anesthetics. They are less flammable than diethyl ether and are therefore safer to store and work with. Penthrane and enthrane (trade names) are two of the more commonly used members of this family ... 

A monument to ether, probably the world s only monument to a drug, stands in a prominent place in Boston s Public Garden. This 40-foot-tall tribute commemorates the first use of ether as an anesthetic under the Etherdome at Massachusetts General Hospital on October 16,1846. 

Diethyl ether [60-29-7] is one of the more important members of the ether family. It is a colorless, very volatile, highly flammable Hquid with a sweet, pungent odor and burning taste. As a commercial product it is available in several grades it is used in chemical manufacture, as a solvent, extractant, or reaction medium, and as a general anesthetic. 

Vinyl Ether. Vinyl ether is manufactured by the pyrolytic dehydrochlorination of 1,1 -dichloroethyl ether. Vinyl ether is used as a general inhalation anesthetic for procedures of short duration. Approximately 4% ethanol is added to the vinyl ether used as an anesthetic to reduce ice formation in the masks used for adrninistration (see also Vinyl polymers). 

Inhalation of other general anesthetics susceptible to abuse, such as ether and chloroform, appears to be limited to health professionals who have easy access to these compounds and who tend to use these dtugs in isolation. Recreational and social use of these substances has been somewhat limited by their high flammability and by frequent and intense undesirable adverse effects at moderate doses. It has been suggested that the abuse of ether or chloroform alone is a rare phenomenon (Delteil et al. 1974 Deniker et al. 1972), occurring usually in the context of dependence on othet substances, particularly alcohol (Krenz et al. 2003). 

The earliest inhaled general anesthetic that found significant use is chloroform, CHCI3, more systematically trichloromethane, a simple derivative of methane. Chloroform was gradually replaced by diethyl ether, commonly known simply as ether, a safer and more effective molecule than chloroform. 

Diethyl ether was the inhalation anesthetic of choice during my childhood. Happily, 1 had rather little need of it. Ether was replaced years ago by a family of superior inhaled general anesthetics, most of which are ethane derivatives. The notable exception is another very simple molecule, nitrous oxide, N2O, frequently known as laughing gas. N2O has been around for a long time and was once a party drug. ... 

Mild burning of the eyes after acute exposure to either trow-1,2-dichloroethylene vapor or aerosol was reported by two subjects in a 1936 self-experimentation study. However, dichloroethylene has been used in combination with ether as a general anesthetic in at least 2000 cases with no evidence of ocular toxicity ... 

An effective anesthetic agent must be easy to use, quickly render the patient unconscious, and not produce any toxicity. Dr. William T. G. Morton first publicly demonstrated the use of ether as an effective anesthetic agent at the Massachusetts General Hospital on 16 October 1846 before a crowd of skeptical physicians. Raymundus Lullius, a Spanish chemist, discovered ether (CH3CH2)20 in 1275. Its hypnotic effects were soon appreciated (and enjoyed by some), but for many decades ether was only used to treat the occasional medical ailment. Even with ether, the success of surgical procedures did not improve until the introduction of antiseptic procedures and infection control some 20 years later. Ether was replaced by cyclopropane in 1929, which was replace by halothane in 1956. While anesthetic agents are desirable for the patient, exposure of hospital staff is highly undesirable and an important occupational consideration. 

Diethyl ether is publicly used as a general anesthetic. 

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