Flumazenil and midazolam in anaesthesia

Flumazenil, the first benzodiazepine antagonist, is currently used widely as an emergency drug, and has also been utilized in planned procedures, to time arousal intra- or post-operatively. It is known that flumazenil, used at the end of a procedure, causes instant recovery by reversing the residual effects of, for example, midazolam. An agonist-antagonist concept, midazolam-flumazenil, where benzodiazepine sedation or anaesthesia is terminated at will, is, therefore, finding increasing application. In neuroanaesthesia, for example, it facilitates immediate recovery, cardiovascular stabilization and the use of midazolam as an alternative to thiopentone and inhalational agents, and in ear, nose and throat endoscopies, it permits more rapid turnover of patients and is a good choice for haemodynamic stability in patients with a high cardiovascular risk factor. There continues to be debate over the term used to describe the level of sedation remaining after the effects of the antagonist have worn off. 'Resedation' is often used incorrectly to describe what is in reality residual sedation. Given the correct use of midazolam or the exploitation of synergism using opioids, flumazenil will cause arousal, while maintaining the benefit of opioid analgesia. Such a technique may eliminate the need for formal recovery facilities in many ambulatory patients, thereby reducing dependence on trolleys, beds and nurses. This has major implications for health economics, particularly in relation to endoscopy clinics and when co-induction of anaesthesia is employed.