Topical sevofluran: a galenic experience

Abstract

Sevoflurane is a volatile liquid from the family of ether-derived alogenated hydrocarbons that is approved for the induction and maintenance of inhalational general anesthesia in the hospital setting. This review describes the pioneering experience of a Spanish Pain Unit in the home treatment of complicated painful wounds using topical sevoflurane instillations according to a protocol approved for off-label use. Aspects of safety and efficacy, both analgesic, antimicrobial and pro-healing are addressed, and some future lines of research are discussed in terms of new formulations for topical use. After more than seven years of use of the protocol, an experience of over 70,000 applications of topical sevoflurane has been gained. In general terms, the analgesic effect appears quickly, is highly intense and persists for several hours. As a result, patients can reduce their consumption of systemic analgesics and benefit from an improvement in their quality of life. In addition, there are signs that suggest sevoflurane also possesses antimicrobial and pro-healing properties. Regarding safety, pruritus at the level of the periulcerous skin is the most frequently reported adverse effect, although it is usually transient and well-tolerated, and no systemic toxicity has been reported. Overall, the risk-benefit balance of the drug has so far been very favorable. To avoid manipulation of this volatile liquid, we have developed a new formulation of sevoflurane in gel form, which has made it possible to successfully apply sevoflurane in the context of painful pathologies where the skin remains intact. Furthermore, these types of new formulations, including sevoflurane microspheres, which we have also developed, could improve the efficacy and safety of topical sevoflurane while reducing the occupational exposure of healthcare staff. This means that the development of new formulations is a field with a very promising future.