Clinical experience with fluothane, a new non-explosive anaesthetic agent

Abstract

FoR ~ANY YEARS anaesthetists have felt the need for a non-explosive anaesthetic agent possessing none of the. disadvantages assocmted with chloroform, trichlorethylene and mtrous o~ide, rhat is, the agent should be non-hepatotoxm, stable in the presence of soda lime and heat, an~ have a high therapeu :ie ratio. Since most heavily fluorinated hydrocarbons are not m2qamma)le, and many possess anaesthetic properties,, they present interesting pos,,ibilities. Robbins (1) found that some hydrocarbons had greater therapeutic rati.os than chloroform or ether, but that when they were used, severe hypotension, cardiac arrhythmias and slamulation of skeletal mtlscle occurred. In 1956, Rav ent6s and Suckhng synthesized and investigated a series of fluorinated hydrocarbons, and one in particular-CF8 CHC [Br (Fluothane)-was found to have potent anaesthetic properties (2). The first clinical trial has been reported by Johnstone (8)_who studied the human cardiovascular response to Fluqthane| PH-YSmAL I~OPFmTmS Fluothane| is a clear colourless liquid wath a rather pleasant odour. It has a specific gravity of 1 86 at 20 ~ C. and a bolhng point of 50.2. ~ C. Vapour pressur~ at 20 ~ C. is 248 rnm. Hg. Off/water solubility is 880 compared to 100 for chlo{oform and 8~2 for ether. When exposed to hght, Fluothane decomposes slowly, forming volatile acids. This can be prevented by storing it in amber-coloured bottles or by adding thymol 0.01 per cent W/W. Fluothane is non-infammable, non-explosive and stable in the presence of soda hme. Fluothane should not be confused with Fluomar| (trittuoro-ethyl-vinyl ether), an inflammable fuorinated ether with somewhat different properties, described by Orth (4) and Gamza, et d. (5). PHARMACOLOGY Ravent6s (2) investigated the pharmacological actaons o]: Fluothane in-animals and reported that full surgical anaesthesia was achieved after using a 2-4 per cent concentration of Fluotaane in air or oxygen for two tc five minutes. Anaesthesia was maintained with a concentration of 3.,t-0.8 per cent in premedicated dogs, and 1-1.2 per c.ent in unpremedicated ones. On the basis of aFluothane@ was supphed by Ayerst,

Plasma Concentrations of Catecholamines Following Adrenaline Infiltration During Gynaecological Surgery

“…Although most authors (Hall and Norris, 1958;Matteo, Katz and Papper, 1962;Forbes, 1966;Katz and Katz, 1966;Wallbank, 1970;Brock-Utne, 1972) who advocate the infiltration of adrenaline recommend dilute solutions and limitations of total dose, some have decried the use of adrenaline as an aid to haemostasis (Chang, Macartney and Graves, 1957;Johnstone and Nisbet, 1961;Varejes, 1963).…”

The changing pattern of anesthesia, 1954-2004: a review based on the content of theCanadian Journal of Anesthesia in its first half-century

“…For example, war-time fluorine research, spawned by the need for high-octane aviation fuel and for enriched uranium235, furthered the postwar fluorine-related research on potential anesthetic agents, which had actually begun as early as 1932. Halothane, introduced in 1956, was described in the Canadian Journal in 1957, 29 as was fluoromar. 30 Methoxyflurane was noted in 1961, 31 enflurane in 1966, 32 and isoflurane in 1971.…”

Halothane Concentration

“…Colley and his colleagues. Nevertheless, in view of (1) the angiomata in the skin, (2) They mention the occasional occurrence of similar glomerular epithelial cell " ballooning " in the nephrotic syndrome and in certain lipid-storage diseases, but they are not able satisfactorily to associate these changes with the other features of the disease. I believe it may be possible to add to existing knowledge of the pathogenesis of the kidney lesion in angiokeratoma corporis diffusum by contrasting the glomerular and tubular effects with those found in rats treated with deoxycortone acetate and excess salt.…”