Evaluation of fluothane for clinical anaesthesia

Abstract

PHARMACOLOGICAL DEVELOPMENTS are unfolding so rapidly in the realm of anaesthesia that almost every week a new drug is made available for study and trial. With the increasing use of the cautery and the concerted effort to avoid explosions, a marked need has arisen for a safe, potent, non-inflammable inhalation anaesthetic drug. Robbms (1) in 1946 investigated a number of non-explosive fluorinated hydrocarbons an the laboratory and conc]uded that stx might be of clinieal value No further work was done until 19N3; when Krantz et al. (9.) reported on the safety of a fluorinated ethyl vinyl ethei. Unfortunately, this compound was explosive In anaesthelac concentrations (8). Meanwhile, Suckling in England, while screening non-explosive fluoride compounds, synthesized 2 bromo-2 ehloro-l,l,1, trittuoroethane (CF3CHC1Br). This compound, c,alled Fluothane, was investigated pharmacologically by Raventos (4), who found it to be a potent and safe anaesthelae drug m several speems of ammals. Within the last year several clinical reports attesting to the value of this drughave been published (5, 6, 7, 8). Fluothane is a clear, colourless llqmd with a sweet, pleasant odour resembling triehlorethylene or chloroform (Table I). The boiling point (50.2~ renders TABLE I PHYSICAL PROPERTIES OF FLUOTItANE Appearance Colourless, clear Odour Sweet, pleasant Molecular welght 197 39 Bmhng point 50 2 ~ C Specific gravity 1 862 at 22 ~ C Off/water solubdlty 330 Vapour pressure 243 mm at 20 ~ C

Influence of halothane and catecholamines on heart rate and rhythm in the horse

“…Black, Clarke, Howard & McCullough (1969), on the other hand, recorded extraventricular beats in only two of eleven cats anaesthetized with halothane. Recordings in man indicate that the incidence of arrhythmias during halothane anaesthesia is of the order of 15 to 20% (Burnap et al, 1958;Hellewell & Potts, 1965;Johnstone, 1966a, b;Stephen et al, 1957;Wyant et al, 1958). It should be noted, however, that two groups of workers state specifically that abnormalities of cardiac rhythm occur in man only in the presence of hypercarbia (Black, Linde, Dripps & Price, 1959;Payne & Senfield, 1964).…”

“…Arrhythmias have also been recorded during halothane anaesthesia in man (Burnap, Galla & Vandam, 1958;Hellewell & Potts, 1965;Johnstone, 1966a, b;Stephen, Grosskreutz, Lawrence, Fabian, Bourgeois-Gavardin & Coughlin, 1957;Wyant, Merriman, Kilduff & Thomas, 1958), although the incidence appears to be less frequent than in the cat. Under halothane anaesthesia, irregularities of cardiac rhythm were not recorded in the dog by Raventos (1956), but in the horse arrhythmias were reported by Vasko (1962) and Eberly, Gillespie, Tyler & Fowler (1968).…”

Halothane and Liver Dysfunction: a Retrospective Study

“…(Burns et al, 1957;Stephen et al, 1957;Robson and Sheridan, 1957;Brindle et al, 1957 ;Virtue et al, 1958 ;Little et al, 1958;Carson et al, 1959 ;Visser and Tarrow, 1959 ;Bianchetti et al, 1960). With this background it therefore came as something of a surprise when the reports of serious and often fatal hepatic complications appeared.…”

Newer anesthetics end their uses

“…Halothane is not irritating to the airway; its vapor is readily accepted during induction of anesthesia without salivation, coughing, "breath-holding," laryngospasm, or bronchoconstriction. 186 As anesthesia develops, the rate of breathing increases while the depth decreases, therefore, respiratory acidosis may occur without surgical stimulation. If air is used during induc-tion, the progressive hypoventilation leads to hypoxemia.…”