| Chemical Properties | colourless liquid |
| Originator | Forane,Ohio Medical,US,1980 |
| Uses | Isoflurane is a volatile anesthetic agent mainly used to study its interaction with the biological system. |
| Uses | Isoflurane is a halogenated ether used for inhalational anesthesia. Recent studies suggest that there might be a relationship between administration of isoflurane and postoperative cognitive dysfunction (POCD). |
| Uses | Solvent and dispersant for fluorinated materials. |
| Definition | ChEBI: Isoflurane is an organofluorine compound. It has a role as an inhalation anaesthetic. It is functionally related to a methoxyethane. |
| Manufacturing Process | A 1-liter 3-necked stainless steel flask was fitted with a copper "Dry Ice" coldfinger condenser, a stainless steel stirring shaft and gland and a copper gasinlet tube. To the flask there was then added 50 g (0.23 mol) ofCF3CHClOCHCl2 and 1.5 g of SbCl5 · HF gas was then slowly bubbled throughthe stirred mixture which was maintained at 0°C. The reaction was run until0.35 mol of HCl was collected, as indicated by the titration of the effluent gaswhich was dissolved in water. Following the fluorination 26 g of material wererecovered and determined to be 90% pure by vapor phase chromatography.Fractional distillation using a 30 x 0.5 cm column packed with glass helicesgave the pure product, BP 48°C to 48.5°C. |
| Brand name | Forane (Baxter Healthcare). |
| Therapeutic Function | Inhalation anesthetic |
| Biological Functions | Isoflurane (Forane) is a structural isomer of enfluraneand produces similar pharmacological properties: someanalgesia, some neuromuscular blockade, and depressedrespiration. In contrast, however, isoflurane is considereda particularly safe anesthetic in patients with ischemicheart disease, since cardiac output is maintained,the coronary arteries are dilated, and the myocardiumdoes not appear to be sensitized to the effects of catecholamines.Also, blood pressure falls as a result of vasodilation,which preserves tissue blood flow. Isofluranecauses transient and mild tachycardia by direct sympatheticstimulation; this is particularly important in themanagement of patients with myocardial ischemia.
Unlike enflurane, isoflurane does not produce aseizurelike EEG pattern. Furthermore, the metabolictransformation of isoflurane is only one-tenth that ofenflurane, so fluoride production is quite low. Amongthe halogenated hydrocarbons, isoflurane is one of themost popular, since it preserves cardiovascular stabilityand causes a low incidence of untoward effects. |
| General Description | Isoflurane is a volatile liquid (bp＝48.5°C) with an MAC of1.15, a blood:gas partition coefficient of 1.43 and high solubilityin fat. Isoflurane is a structural isomer of enflurane. Itis a known respiratory irritant, but less so than desflurane.Approximately 0.2% of the administered drug undergoesmetabolism, the rest is exhaled unchanged. The metabolismof isoflurane yields low levels of the nephrotoxic fluoride ionas well as a potentially hepatotoxic trifluoroacetylating compound). The relatively low concentrations ofthese compounds have resulted in very low risks of hepatotoxicityand nephrotoxicity. There have been no reports ofseizures caused by isoflurane and only transient increases inheart rate have been reported. |
| Biochem/physiol Actions | Isoflurane is a tandem pore potassium channel activator. It is also a very widely used anesthetic for animal research and for in vitro studies on anesthesia mechanisms. |
| Clinical Use | Isoflurane was introduced in the United States in 1981 and is a potent anesthetic agentwith many similarities to its isomer enflurane (potent, nonflammable, and intermediate bloodsolubility). It does produce significantly fewer cardiovascular effects than enflurane, however, andit can be used safely with epinephrine without as great a concern for arrhythmia production.Isoflurane has a more pungent odor than halothane and, thus, can cause irritation to the throat andrespiratory tract, triggering coughing and laryngospasm. To overcome this problem, it often issupplemented with intravenous agents. Less than 0.2% of an administered dose is metabolized,mostly to fluoride and trifluoroacetic acid. Some minimal potentialfor hepatotoxicity is associated with a trifluoroacetyl halide metabolite. |
| Synthesis | Isoflurane is prepared by chlorinationof 2,2,2-trifluoroethoxydifluoromethane, itselfobtained by alkylation of trifluoroethanol withdifluorochloromethane , :
|
| Veterinary Drugs and Treatments | Isoflurane is an inhalant anesthetic that has some distinct advantagesover either halothane or methoxyflurane due to its lessenedmyocardial depressant and catecholamine sensitizing effects, andthe ability to use it safely in patients with either hepatic or renaldisease. Isoflurane’s higher cost than either methoxyflurane or halothaneis a disadvantage.
Horses may recover more rapidly than with halothane, but bemore susceptible to anesthetic associated-myopathy. |
| Raw materials | ANTIMONY(V) CHLORIDE-->BIS(CHLOROMETHYL)ETHER-->2,2,2-Trifluoroethanol-->HYDROGEN FLUORIDE GAS-->2,2,2-TRIFLUOROETHYL METHYL ETHER-->1-CHLORO-2,5-DIMETHYL-4-NITROBENZENE2-CHLORO-5-NITRO-P-XYLENE-->hydrogen fluoride-->Hydrogen fluoride-->Methanol, difluoro- (6CI,8CI,9CI)-->DIFLUOROMETHYL 2,2,2-TRIFLUOROETHYL ETHER-->1,1-Dichloro-2,2,2-trifluoroethane-->1,1-DICHLORO-2,2,2-TRIFLUOROETHYL DIFLUOROMETHYL ETHER |
| Preparation Products | Desflurane-->2-Chloro-1,1,1,2-tetrafluoroethane |
