The Fluorinated Anesthetics
Certain hydrocarbons such as ethylene and cyclopropane elicit surgical anesthesia when inhaled in sufficient concentrations. The saturated hydrocarbons of the aliphatic series do not evoke anesthesia. Anesthetic properties are conferred upon the lower mem
- PDF / 7,509,160 Bytes
- 64 Pages / 439.37 x 666.142 pts Page_size
- 100 Downloads / 233 Views
The Fluorinated Anesthetics By
JoHN C. KRANTZ JR. and FRIEDA G. Runo With 5 Figures
Experimental work with fluorinated anesthetics I. General introduction Certain hydrocarbons such as ethylene and cyclopropane elicit surgical anesthesia when inhaled in sufficient concentrations. The saturated hydrocarbons of the aliphatic series do not evoke anesthesia. Anesthetic properties are conferred upon the lower members of this series of hydrocarbons by halogenation with either chlorine or bromine. For example, chloroform and ethyl chloride have been used as anesthetics for more than a century. It therefore appeared prudent to determine the effect of halogenation of hydrocarbons and ethers with fluorine in order to determine what effect the presence of fluorine in the molecule would exert on the anesthetic properties of these compounds. The wisdom of this effort has been justified by the investigations of the last two decades, leading to the production of the most useful anesthetic agents containing fluorine. This chapter portrays this signal advance in the field of anesthesiology. The compounds considered in this chapter are fluorine containing hydrocarbons and ethers (with or without other halogens) which elicit anesthesia or have been tested for anesthetic properties. To facilitate the organization of the material the chapter is divided in two parts: in the first part the experimental work in the field of fluorinated anesthetics is arranged in historical sequence and only mention is made of those compounds now used clinically. These are discussed in detail in part II along with extensive pharmacologic studies of these agents.
II. Historical development of fluorinated hydrocarbons and ethers A. Early studies of fluorinated hydrocarbons The first organic compound of fluorine prepared was the gas CF 4 (PARTINGTON 1925). It was synthesized accidentally in an unsuccessful attempt to isolate elemental fluorine in a carbon vessel. Tetrafluoromethane has no anesthetic properties. Today the number of fluorine-containing hydrocarbons and ethers is legion. When the fluorinated members of the lower aliphatic hydrocarbons became available, most of the studies on these compounds were concerned with their use as refrigerants (BooTH and BIXBY, 1932). STRUCK and PLATTNER (1940) investigated the possible anesthetic properties of C4F 10 , C5F 10 and C6F 12 • Mice exposed F. A. Smith (ed.), Pharmacology of Fluorides © Springer-Verlag Berlin Heidelberg 1966
502
Historical development of fluorinated hydrocarbons and ethers
Table 1. The concentrations of various halogenated hydrocarbons necessary to produce anesthesia and respiratory arrest in 50% of the mice exposed Also the time necessary for induction of anesthesia as well as times necessary for recovery of pain sensation and ability to walk after exposure to the LD 50 for 10 minutes are given. Time
Formula
A. I
P.
w.
Remarks
Fluorine substituted hydrocarbons and ethers
CF3 CH3
-46
CF 3CH=CH 2
-24
60
CF3 CH 2CHa CF 3CH 2CF3 CH 3CF 2CF 2CH 3 CH 3 CF 2CH=CH 2 CH3 CF 2CH 2CH
Data Loading...
