Isoflurane, safety

Literally hundreds of substances in addition to ether and chloroform have subsequently been shown to act as inhaled anesthetics. Halothane, enflurane, isoflurane, and methoxyflurane are at present the most commonly used agents in hospital operating rooms. All four are potent at relatively low doses, are nontoxic, and are nonflammable, an important safety feature. 

Kissin I, Morgan PL, Smith LR (1983) Comparison of isoflurane and halothane safety margins in rats. Anesthesiol 58 556-561... 

Modem inhalation anesthetics are fluoiinated to reduce flammabihty. Initially, these inhaled agents were believed to be biochemically inert. Over the past 30 years, however, research findings have demonstrated that not only are inhaled anesthetics metabolized in vivo [27], but their metabolites are also responsible for both acute and chronic toxicities [28,29]. Therefore, the use of some anesthetics has been discontinued, including methoxyflurane because of its nephrotoxicity and other anesthetics are more selectively used, e.g. halothane due to a rare incidence of liver toxicity. Studies have also provided the impetus to develop new agents - isoflurane and desflurane - with properties that lower their toxic potential. The result has been improved safety, but there is room for further improvement as our insight into toxicological mechanisms expands. 

Sokoll MD, Geigis SD, Mehta M, Ali NN Lineberry C. Safety and efficacy of atracurium (BW33A) in suigical patients receiving balanced or isoflurane anesthesia. Anesthesiology (1983) 58,450-5. 

White CM, Dunn A, Tsikouris J, Waberski W, Felton K, Freeman-Bosco L, Giri S, Kluger J. An assessment of the safety of short-term amiodarone therapy in cardiac surgical patients with fentanyl-isoflurane anesthesia. AnesthAnalg (1999) 89, 585-9. 

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