The Effect on the Recovery Profile of a Change from Enflurane to Desflurane during the Latter Part of Anaesthesia

This study compared emergence and recovery characteristics after either enflurane anaesthesia or crossover from enflurane to desflurane anaesthesia. At an estimated 1 h prior to the end of operation, enflurane was either reduced (group E, n = 23) or replaced with desflurane (group X, n = 23). At the end of the operation, emergence and recovery characteristics of the two groups were compared. The crossover technique accelerated recovery compared with enflurane anaesthesia. The time taken for the eyes to open in response to painful pinching or a verbal command, and to regain awareness of age and name, were significantly shorter after crossover anaesthesia than after enflurane anaesthesia. The digit symbol substitution test and serial seven test scores were significantly better in patients subjected to crossover anaesthesia than in those subjected to enflurane anaesthesia. We conclude that, during surgery, the substitution of enflurane with desflurane in the latter part of anaesthesia can improve recovery.

Pre-operative prediction of ‘dry taps’

Objectives:The treatment of children with ‘glue ear’ often presents surgeons with the question of whether or not to insert a grommet when myringotomy reveals no fluid in the middle ear. We present a study designed to assess which factors contribute to the presence of a ‘dry tap’.Design:We prospectively gathered data from a cohort of 280 children (504 myringotomies). The cohort included two subgroups, one received halothane and nitrous oxide anaesthesia, and the other received enflurane anaesthesia.Setting:The ENT department of a district general hospital.Participants:Children (aged less than 17 years) requiring myringotomy.Main outcome measures:The presence of a ‘glue’ or dry tap at myringotomy was documented. We also recorded data on the following: pre- and post-induction tympanometry; age; season; anaesthetic type; and the delay from listing to actual operation.Results:A non type B pre-induction tympanogram and delay to operation were strong indications of finding a dry tap at surgery.Conclusions:In our study population, the proportion of dry taps at myringotomy was 18 per cent. The presence of a dry tap was rarely due to the induction of anaesthesia. Multivariate analysis revealed that the combination of factors most likely to predict a dry tap were non type B tympanogram and delay to operation.