Fluorine inhalation anesthetics

Table 1. Physical Properties of Fluorinated Inhalation Anesthetics...

The good adsorbability of fluorocarbons can be employed for the recovery of, for example, fluorinated inhalation anesthetics from the air of anesthesia machines.18... 

The above reaction is of particular interest because the product Y is the well-known inhalation anesthetic Halothane that replaced ether and other flammable and therefore dangerous anesthetics in the late 1950s. Nowadays, Halothane is, at least in the United States, replaced by even better fluorinated inhalation anesthetics. 

N.C. Yang, K.L. Hwang, C.H. Shen, H.F. Wang, W.M. Ho, Simultaneous determination of fluorinated inhalation anesthetics in blood by gas chromatography-mass spectrometry combined with a headspace autosampler, J. Chromatogr. B, 159, 307-318 (2001). 

Halofluorocarbons and highly fluorinated ethers have been used as inhalation anesthetics for many years [91], The first anesthetic of this type was Halothane which was introduced clinically in 1956 [92], An excellent anesthetic with few unwanted side-effects, Halothane has the particular advantages of high chemical stability and non-flammability. Several alternative heavily fluorinated inhalation anesthetics have subsequently been introduced [93] (Scheme 4.42). 

A number of inhalation anesthetics have been introduced to clinical practice, some of which are Hsted in Table 1. AH agents introduced after 1950, except ethyl vinyl ether, contain fluorine. Agents such as ether, chloroform, trichloroethylene (Tdlene), cyclopropane, and fluoroxene (Fluoromar), which were once used, have been displaced by the newer fluorinated anesthetics. 

Desflurane is less potent than the other fluorinated anesthetics having MAC values of 5.7 to 8.9% in animals (76,85), and 6% to 7.25% in surgical patients. The respiratory effects are similar to isoflurane. Heart rate is somewhat increased and blood pressure decreased with increasing concentrations. Cardiac output remains fairly stable. Desflurane does not sensitize the myocardium to epinephrine relative to isoflurane (86). EEG effects are similar to isoflurane and muscle relaxation is satisfactory (87). Desflurane is not metabolized to any significant extent (88,89) as levels of fluoride ion in the semm and urine are not increased even after prolonged exposure. Desflurane appears to offer advantages over sevoflurane and other inhaled anesthetics because of its limited solubiHty in blood and other tissues. It is the least metabolized of current agents. 

Methoxyflurane is an extremely powerful inhalation anesthetic that is an excellent skeletal muscle relaxant. However, its use is somewhat limited by its relatively high solubility, which causes the patient to make a slow transition back into consciousness. Another disadvantage of methoxyflurane is that fluorine ions are the product of its biotransformation, which may lead to the development of renal failure. Therefore, it is recommended to use methoxyflurane for anesthesia during interventions of no more than 2 h. A very common synonym for methoxyflurane is penthrane. 

Inhalation anesthetics -fluorine compounds [FLUORINECOMPOUNDS,ORGANIC - INTRODUCTION] (Vol 11)... 

Protein Theories. The direct interaction of inhalation anesthetics and proteins has been proposed as the cause of anesthesia. An inhalation agent, whether a noble gas or a fluorinated ether, could dissolve asymmetrically in a protein, Resultant conformational changes in the protein, if these changes occur, could then cause changes in biological activity. 

The difluoromethylation of aliphatic alcohols is also possible, in principle, but the resulting difluoroethers often tend to undergo acid-catalyzed hydrolysis to the corresponding formates. They are only stable if the corresponding alcohol is sufficiently acidic, i. e. if it carries electron-withdrawing substituents. O-Difluoro-methylated carbohydrates have been reported [7]. In contrast, some highly fluorinated alkyl difluoromethyl ethers can be synthesized under quite drastic conditions (Scheme 2.168), and because of their extreme stability they can be used as inhalation anesthetics [3, 8]. 

Modem inhalation anesthetics are fluorinated to reduce the flammabihty. They were initially considered to be biochemically inert substances. However, with time came the recognition that not only are inhaled anesthetics metabolized in vivo [27] but also that their metabolites are responsible for both acute and chronic toxicities [28, 29]. Information gained from research over the past 30 years has led to changes in anesthesia practice, discontinuing the use of some anesthetics, for example methoxyflurane, due to its nephrotoxicity and more selective use of others, i.e. halothane, due to its rare liver toxicity. It has also provided the impetus for the development of new agents, isoflurane and desflurane, with properties that lower their toxic potential. The result has been improved safety but room remains for further improvement as our insight into toxicological mechanisms expands. 

Aerrane BRN 1852087 CCRIS 3043 Compound 469 EINECS 247-897-7 Forane Forene Isoflurane Isofiurano Isofluranum R-E 235dal. Ah inhalation anesthetic solvent and dispersant for fluorinated materials. Gas bp = 48.5 sg n 1.45 non-flammable soluble in most organic solvents. Anaquest ElfAtochem N. Am. 

Electrochemical fluorination (ECF) is an effective procedure to replace C—H bonds with C—F bonds in an organic molecule to produce fluorocarbons for a host of uses, particularly in industrial applications. Included in medicinal applications of per-fluorinated molecules are their use as inhalation anesthetics and in the development of oxygen carriers. ... 

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