This Article Full Text Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a colleague Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Request Permissions Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (3) Citing Articles via Google Scholar Google Scholar Articles by Hecker, K. E. Articles by Rossaint, R. Search for Related Content PubMed PubMed Citation Articles by Hecker, K. E. Articles by Rossaint, R. Related Collections Pharmacology

---

ANESTHETIC PHARMACOLOGY

Minimum Anesthetic Concentration of Sevoflurane with Different Xenon Concentrations in Swine

Klaus E. Hecker, MD^*, Jan H. Baumert, MD DEAA^*, Nicola Horn, MD^*, Matthias Reyle-Hahn, MD, Nicole Heussen, MSc, and Rolf Rossaint, MD PhD^*

Departments of *Anesthesiology and Medical Statistics, Universitätsklinikum der RWTH Aachen, Aachen, Germany, and the Department of Anesthesiology and Intensive Care, Waldkrankenhaus Berlin, Berlin, Germany.

Address correspondence and reprint requests to Klaus Hecker, Klinik für Anaesthesiologie, Klinikum der RWTH Aachen, Pauwelsstr. 30, 52074 Aachen, Germany. Address email to klaus.hecker{at}post.rwth-aachen.de

In a previous study, we described a partial antagonism of xenon (Xe) in combination with isoflurane. One hypothetical explanation suggested that Xe and isoflurane probably induced anesthesia via different pathways at the neuronal level. This warranted investigating the combination of Xe with other inhaled anesthetics to examine the relationship between Xe and volatile anesthetics in general. We therefore investigated the influence of Xe on the minimum alveolar concentration (MAC) of sevoflurane. The study was performed in 10 swine (weight 30.8 kg ± 2.6, mean ± SD) ventilated with xenon 0%, 15%, 30%, 40%, 50%, and 65% in oxygen. At each Xe concentration, various concentrations of sevoflurane were administered in a stepwise design. For each a supramaximal pain stimulus (claw clamp) was applied. The appearance of a withdrawal reaction was recorded. The sevoflurane MAC was defined as the end-tidal concentration required to produce a 50% response rate. At each Xe concentration, the animals’ responses to the pain stimulus were categorized and a logistic regression model was fitted to the results to determine sevoflurane MAC. Sevoflurane MAC was decreased by inhalation of Xe in a linear manner from 2.53 with 0% Xe to 1.54 with 65% Xe. In contrast to Xe and isoflurane, the anesthetic effects of Xe and sevoflurane appear to be simply linear.

IMPLICATIONS: We investigated the influence of the anesthetic gas, xenon, on the minimum alveolar concentration (MAC) for the volatile anesthetic sevoflurane. The study was performed in 10 swine ventilated with fixed xenon and various concentrations of isoflurane. The sevoflurane MAC is decreased by inhalation of xenon in a linear relationship.

This article has been cited by other articles:

				E. I. Eger II, M. Tang, M. Liao, M. J. Laster, K. Solt, P. Flood, A. Jenkins, D. Raines, J. F. Hendrickx, S. L. Shafer, et al. Inhaled Anesthetics Do Not Combine to Produce Synergistic Effects Regarding Minimum Alveolar Anesthetic Concentration in Rats Anesth. Analg., August 1, 2008; 107(2): 479 - 485. [Abstract] [Full Text] [PDF]

				J. F. A. Hendrickx, E. I. Eger II, J. M. Sonner, and S. L. Shafer Is Synergy the Rule? A Review of Anesthetic Interactions Producing Hypnosis and Immobility Anesth. Analg., August 1, 2008; 107(2): 494 - 506. [Abstract] [Full Text] [PDF]