Abstract
The development of inhaled anesthetics (IAs) has a rich history dating back many centuries. In modern times they have played a pivotal role in anesthesia and critical care by allowing deep sedation during periods of critical illness and surgery. In addition to their sedating effects, they have many systemic effects allowing for therapy beyond surgical anesthesia. In this narrative review we chronicle the evolution of IAs, from early volatile agents such as ether to the contemporary use of halogenated hydrocarbons. This is followed by a discussion of the mechanisms of action of these agents which primarily involve the modulation of lipid membrane properties and ion channel activity. IAs' systemic effects are also examined, including their effects on the cardiovascular, respiratory, hepatic, renal and nervous systems. We discuss of the role of IAs in treating systemic disease processes including ischemic stroke, delayed cerebral ischemia, status epilepticus, status asthmaticus, myocardial ischemia, and intensive care sedation. We conclude with a review of the practical and logistical challenges of utilizing IAs outside the operating room as well as directions for future research. This review highlights the expanding clinical utility of IAs and their evolving role in the management of a diverse range of disease processes, offering new avenues for therapeutic exploration beyond anesthesia.