Halothane and Hepatitis

Abstract

Despite early controversy, it is now recognised that halothane anaesthesia may be followed by abnormalities of liver function. The resulting hepatitis may take 1 of 2 forms: in type I, there is a minor degree of disturbance of liver function shown by increased serum transaminases or glutathione-S-transferase in up to 25 to 30% of patients; subsequent re-exposure to halothane is not necessarily associated with evidence of liver damage. In contrast, type II hepatitis is often associated with massive liver cell necrosis, frequently leading to fulminant hepatic failure. This type of liver damage has clinical, serological and immunological features compatible with an immune-mediated idiosyncratic reaction. The incidence is low (between 1 in 3500 and 1 in 35,000 anaesthetic procedures), but the mechanism of halothane hepatitis remains uncertain: there have been extensive animal models showing that halothane has a direct hepatotoxic potential, although the relevance of this to the human patient is not yet clear. Prevention of halothane hepatitis may be difficult, and the only clear way of reducing the incidence is to avoid re-exposure to halothane in those patients who have had a previous adverse reaction to the drug, demonstrated either by unexplained pyrexia or by jaundice. Halothane should also be avoided in those patients where there is a family history of sensitisation to the drug. In such cases, halothane-free equipment should be used, and exposure to other volatile non-halogenated anaesthetics should be avoided.

UV Photodissociation of Halothane in a Focused Molecular Beam: Space-Speed Slice Imaging of Competitive Bond Breaking into Spin–Orbit-Selected Chlorine and Bromine Atoms

“…In this work, in an apparatus newly assembled and operating in Osaka, we have studied the photodissociation of 2-bromo-2-chloro-1,1,1-trifluoroethane (halothane) at 234 nm. In halothane, two different halogen atoms, Br and Cl, are bound to the same C atom (CF and CH bonds cannot break for photolysis at this wavelength): this molecule is thus prototypical for exhibiting competitive dissociation features under UV light radiation: these photodissociation pathways are very interesting to be individuated, well beyond the viewpoint of reaction dynamics (which is our main concern here), but are also worthy of paying considerably valuable attention for models of ozone depletion in the stratosphere. , Halothane is archetypal of fluorocarbons of high environmental impact: it has unique anesthetic action, and thus, it is employed for medical treatment: generally, it does not completely decompose inside the human body, so the amount of its release into the atmosphere is relevant, as well as its selective photodissociation dynamics, leading in particular to a specific halogen atom.…”

Drug-Induced Hepatic Disorders

“…However, if the following guidelines are obeyed some cases of halo alkane hepatitis may be prevented (D0ssing et al 1982;Neuberger 1990). enflurane and methoxyflurane) by reducing the dose or discontinuing treatment.…”

Hepatotoxicity of Halogenated Inhalational Anesthetics

“…Obesity is another risk factor, possibly because of accumulation of halothane in adipose tissue. Induction of CYP2E1 by phenobarbital, alcohol, and isoniazid are all risk factors for halothane hepatitis ( 20 - 22 ). However, halothane is no longer used in many developed countries but continues to be used in some developing countries.…”