Exposure to methoxyflurane: Low-dose analgesia and occupational exposure

IntroductionEvidence of nephrotoxicity led to abandonment of methoxyflurane anaesthesia. In lower doses via the Penthrox® inhaler, methoxyflurane is used for analgesia. We aim to review the literature to identify the relevance of methoxyflurane as an effective analgesic agent, identify whether there are any patient safety concerns in modern use, and determine occupational risk to healthcare personnel due to environmental methoxyflurane exposure.MethodsArticles were located via PubMed, ScienceDirect, Google Scholar, Anaesthesiology and the Cochrane Library.ResultsSingle low-dose exposure to methoxyflurane may elevate blood fluoride levels below the toxic range, and appears relatively safe for patients. There is limited literature of occupational methoxyflurane exposure within modern parameters. Risks could include nephrotoxicity or hepatotoxicity.ConclusionsThe safety of occupational methoxyflurane exposure is yet to be proved. Further independent studies quantifying occupational exposure and monitoring the health of personnel exposed to methoxyflurane need to be undertaken to ensure safety.

A method for hyperthermic treatment of mouse skin

The Sencar mouse skin system is a recognized model for tumour initiation, promotion and progression. The current interest in the effect of hyperthermia on this multi-stage tumorigenesis model prompted the need for a technique to accurately heat a section of dorsal skin of a large number of mice for 30 min per heat treatment. In the technique described, experimental groups of 25 female Sencar mice were treated at 7-8 weeks of age under general methoxyflurane anaesthesia. Treatment consisted of the application of initiating and/or promoting agents with or without hyperthermia. For hyperthermic skin treatments, each group of mice was placed onto a platform in a water bath so that the dorsal skin of the mice was in contact with 44°C temperature controlled water.