Xenon-based anesthesia: theory and practice

Xenon has been in use as an anesthetic for more than 50 years. Although it exhibits some of the properties of an ideal anesthetic, the technical complexity of xenon equipment and the high cost of the gas have prevented widespread use of xenon anesthesia. The main beneficial features of xenon anesthesia are fast induction and emergence because of low solubility in blood and tissues, along with remarkably stable hemodynamics even in patients with impaired cardiac function. Xenon has proven to be a safe and well-tolerated anesthetic in clinical trials. The primary mechanism by which xenon produces anesthesia - antagonism at the neuronal N-methyl-D-aspartate receptor - and the absence of vasodilating effects distinguish xenon from most other inhaled and intravenous anesthetics. In addition, xenon can protect cells from ischemia-reperfusion damage. This effect was demonstrated in myocardium and neuronal cells as well. Myocardial and cerebral infarction sizes after ischemia can be reduced substantially by xenon, even when administered after the initial insult. Because of its high cost, routine xenon anesthesia may be justified only if it is associated with fewer perioperative complications, shorter duration of hospital stay or significant reduction of perioperative risk. Clinical studies to identify a specific group of patients in which these requirements are met are still lacking.