Assessment of Amnesic Effect and the Depth of Hypnosis During Therapeutic Inhalation of Xenon-Oxygen Mixture

The current literature lacks data on the incidence of intraoperative awakening during xenon anesthesia. This could be due to amnesia preventing memories of the intraoperative awakening.

The objective: to determine the concentration of xenon in the xenon-oxygen mixture, which causes amnesia for events during inhalation in 100% of patients, and to make correlations with the depth of hypnosis as per Kugler scale.

Subjects and Methods: 34 patients with chronic neurogenic pain who received 111 20-minute inhalations with concentration of xenon up to 50% were included in the study. Amnesia evaluation, EEG monitoring, and pain assessment on a visual analog scale (VAS) were performed.

Results. Amnesic effect developed in 100% of patients at xenon concentration of 45%. On inhalation of xenon at concentrations of up to 50%, EEG changes did not exceed D1 grade on Kugler scale. The decrease in bispectral index (BIS) did not reach the level of deep sedation (Me 96.2%) at xenon concentration of 50%. The decrease in pain on VAS was approximately 60%.

Conclusions. Xenon inhalations cause transient congradic amnesia at concentrations of 45% or more. The accuracy of the BIS monitoring readings may be reduced when using xenon in a monovariant. Inhalations of xenon-oxygen mixture in concentrations up to 50% showed good analgesic properties in the framework of combined therapy of chronic pain syndrome.

1. Abuzarova G.R., Khoronenko V.E., Sarmanaeva R.R. et al. Double-blind, randomized, placebo-controlled study of Xenon in cancer pain therapy. Vestnik Intensivnoy Terapii Im. А.I. Saltanova, 2020, vol. 4, pp. 48-57. (In Russ.) doi: 10.21320/1818-474X-2020-4-48-57.

2. Burov N.E., Mironova I.I., Kornienko L.Yu. et al. Clinical stages and subjective sensations during xenon anesthesia. Anesteziologiya i Reanimatologiya, 1993, no. 4, pp. 7-11. (In Russ.)

3. Burov N.E., Molchanov I.V., Nikolaev L.L. Хenon in medicine: past, present and future. Journal Klinicheskaya Praktika, 2011, no. 2, pp. 3-11. (In Russ.) ISSN: 2220-309.

4. Gerasimova Yu.Yu., Ermakov M.A. Neuroprotective effects of subnarcotic and narcotic concentrations of medical xenon. Vestnik Soveta Molodykh Uchenykh i Spetsialistov Chelyabinskoy Oblasti, 2017, no. 3 (18), pp. 21-24. (In Russ.)

5. Grebenchikov O.A., Molchanov I.V., Shpicko A.I. et al. Neuroprotective properties of xenon according to experimental studies. Journal im. N.V. Sklifosovskogo. Neotlozhnaya Meditsinskaya Pomosch, 2020, no. 9 (1), pp. 85-95. (In Russ.) doi.org/10.23934/2223-9022-2020-9-1-85-95.

6. Lisichenko I.A., Gusarov V.G., Teplykh B.A. et al. Assessment of xenon-induced depth of hypnosis according to Kugler’s scale in elderly and senile patients undergoing knee replacement surgery: a prospective open-label cohort study. Vestnik Intensivnoy Terapii Im. А.I. Saltanova, 2022, no. 2, pp. 121-131. (In Russ.) doi.org/10.21320/1818-474X-2022-2-121-131.

7. Potievskaya V.I., Shvetskiy F.M., Sidorov D.V. et al. Assessment of xenon effect on postoperative pain syndrome severity in oncological patients: a randomized study. Vestnik Intensivnoy Terapii Im. А.I. Saltanova, 2021, no. 3, pp. 140-150. (In Russ.) doi: 10.21320/1818-474X-2021-3-140-150.

8. Rozenko D.A., Shikhlyarova A.I., Popova N.N. et al. Efficiency mark postoperative pain management and normalization of adaptation status in patients with reproductive system oncopathology. Yuzhno-RossiyskiyOnkologicheskiy Journal, 2020, no. 2 (1), pp. 14-25. (In Russ.) doi.org/10.37748/2686-9039-2021-2-1-2.

9. Shpicko A.I., Grebenchikov O.A., Molchanov I.V. et al. Cardioprotective properties of xenon. Journal im. N.V. Sklifosovskogo. Neotlozhnaya Meditsinskaya Pomosch, 2020, no. 9 (2), pp. 264-272. (In Russ.) doi.org/10.23934/2223-9022-2020-9-2-264-272.

10. American Society of Anesthesiologists Task Force on Intraoperative Awareness. Practice advisory for intraoperative awareness and brain function monitoring: a report by the American Society of Anesthesiologist’s task force on intraoperative awareness. Anesthesiology, 2006, vol. 104, no. 4, pp. 847-864. doi: 10.1097/00000542-200604000-00031.

11. Cullen S.C., Eger E.I. 2nd, Cullen B.F. et al. Observations on the anesthetic effect of the combination of xenon and halothane. Anesthesiology, 1969, vol. 31, no. 4, pp. 305-309. doi: 10.1097/00000542-196910000-00003.

12. Kugler J. Electroencephalographie in Klinik und Praxis [Electroencephalography in clinics and practice]. 3rd ed. Stuttgart, Thieme, 1981.

13. Malver L., Brokjaer A., Staahl C. et al. Electroencephalography and analgesics. Br. J. Clin. Pharmacol., 2014, vol. 77, no. 1, pp. 72‒95. doi: 10.1111/bcp.12137.

14. Nakata Y., Goto T., Ishiguro Y. et al. Minimum alveolar concentration (MAC) of xenon with sevoflurane in humans. Anesthesiology, 2001, vol. 94, no. 4, pp. 611–614. doi.org/10.1097/00000542-200104000-00014.

15. Pandit J., Andrade J., Bogod D. et al. The 5th National Audit Project (NAP5) on accidental awareness during general anaesthesia: protocol, methods and analysis of data. Anaesthesia, 2014, vol. 69, no. 10, pp. 1078-1088. doi: 10.1111/anae.12811.