Skip to main content
SpringerLink
Log in

Normative values for SedLine-based processed electroencephalography parameters in awake volunteers: a prospective observational study

  • Original Research
  • Published:
Journal of Clinical Monitoring and Computing Aims and scope Submit manuscript

Abstract

Processed electroencephalography (pEEG) is used to monitor depth of anaesthesia and/or sedation. A novel device (SedLine®) has been recently introduced into clinical practice. However, there are no published data on baseline SedLine values for awake adult subjects. We aimed to determine baseline values for SedLine-derived parameters in eyes-open and eyes-closed states. We performed a prospective observational study in healthy volunteers. SedLine EEG-derived parameters were recorded for 2 min with eyes closed and 8 min with eyes open. We determined the overall reference range for each value, as well as the reference range in each phase. We investigated changes in recorded parameters between the two phases, and the interaction between EMG, baseline characteristics, and Patient State Index (PSI). We collected data from 50 healthy volunteers, aged 23–63 years. Median PSI was 94 (92–95) with eyes open and 88 (87–91) with eyes closed (p < 0.001 for open versus close). EMG activity decreased from 47.2% (46.6–47.9) with eyes open to 28.6% (28.0–29.3) with eyes closing (p < 0.001). There was a significant positive correlation between EMG and PSI with eyes closed (p = 0.01) but not with eyes open, which was confirmed with linear regression analysis (p = 0.01). In awake volunteers, keeping eyes open induces significant changes to SedLine-derived parameters, most likely due to increased EMG activity (e.g. eye blinking). These findings have implications for the clinical interpretation of PSI parameters and for the planning of future research.

This is a preview of subscription content, log in via an institution to check access.

Access this article

Log in via an institution

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Institutional subscriptions

Fig. 1
Fig. 2
Fig. 3
Fig. 4

Similar content being viewed by others

References

  1. Gibbs FA, Gibbs EL, Lennox WG. Effect on the electroencephalogram of certain drugs which influence nervous activity. Arch Intern Med. 1937;60:154–66.

    Article  Google Scholar 

  2. Fahy BG, Chau DF. The technology of processed electroencephalogram monitoring devices for assessment of depth of anesthesia. Anesth Analg. 2018;126:111–7. https://doi.org/10.1213/ANE.0000000000002331.

    Article  PubMed  Google Scholar 

  3. Escallier KE, Nadelson MR, Zhou D, Avidan MS. Monitoring the brain: processed electroencephalogram and peri-operative outcomes. Anaesthesia. 2014;69:899–910. https://doi.org/10.1111/anae.12711.

    Article  CAS  PubMed  Google Scholar 

  4. Hajat Z, Ahmad N, Andrzejowski J. The role and limitations of EEG-based depth of anaesthesia monitoring in theatres and intensive care. Anaesthesia. 2017;72(Suppl 1):38–47. https://doi.org/10.1111/anae.13739.

    Article  PubMed  Google Scholar 

  5. Devlin JW, Skrobik Y, Gélinas C, Needham DM, Slooter AJC, Pandharipande PP, et al. Clinical practice guidelines for the prevention and management of pain, agitation/sedation, delirium, immobility, and sleep disruption in adult patients in the ICU. Crit Care Med. 2018;46:e825–73. https://doi.org/10.1097/CCM.0000000000003299.

    Article  PubMed  Google Scholar 

  6. Heyse B, Van Ooteghem B, Wyler B, Struys MM, Herregods L, Vereecke H. Comparison of contemporary EEG derived depth of anesthesia monitors with a 5 step validation process. Acta Anaesthesiol Belg. 2009;60:19–33.

    CAS  PubMed  Google Scholar 

  7. von Elm E, Altman DG, Egger M, Pocock SJ, Gøtzsche PC, Vandenbroucke JP, Initiative STROBE. The strengthening the reporting of observational studies in epidemiology (STROBE) statement: guidelines for reporting observational studies. Ann Intern Med. 2007;147:573–7. https://doi.org/10.7326/0003-4819-147-8-200710160-00010.

    Article  Google Scholar 

  8. Vandenbroucke JP, von Elm E, Altman DG, Gotzsche PC, Mulrow CD, Pocock SJ, STROBE Initiative, et al. Strengthening the reporting of observational studies in epidemiology (STROBE): explanation and elaboration. PLoS Med. 2007;4:e297. https://doi.org/10.1371/journal.pmed.0040297.

    Article  PubMed  PubMed Central  Google Scholar 

  9. Drover D, Ortega HR. Patient state index. Best Pract Res Clin Anaesthesiol. 2006;20:121–8. https://doi.org/10.1016/j.bpa.2005.07.008.

    Article  PubMed  Google Scholar 

  10. Purdon PL, Sampson A, Pavone KJ, Brown EN. Clinical electroencephalography for anesthesiologists: part I: background and basic signatures. Anesthesiology. 2015;123:937–60. https://doi.org/10.1097/ALN.0000000000000841.

    Article  CAS  PubMed  Google Scholar 

  11. Vivien B, Di Maria S, Ouattara A, Langeron O, Coriat P, Riou B. Overestimation of bispectral index in sedated intensive care unit patients revealed by administration of muscle relaxant. Anesthesiology. 2003;99:9–17. https://doi.org/10.1097/00000542-200307000-00006.

    Article  PubMed  Google Scholar 

  12. Inoue S, Kawaguchi M, Sasaoka N, Hirai K, Furuya H. Effects of neuromuscular block on systemic and cerebral hemodynamics and bispectral index during moderate or deep sedation in critically ill patients. Intensive Care Med. 2006;32:391–7. https://doi.org/10.1007/s00134-005-0031-3.

    Article  CAS  PubMed  Google Scholar 

  13. Schuller PJ, Newell S, Strickland PA, Barry JJ. Response of bispectral index to neuromuscular block in awake volunteers. Br J Anaesth. 2015;115(Suppl 1):i95–103. https://doi.org/10.1093/bja/aev072.

    Article  PubMed  Google Scholar 

  14. Prichep LS, Gugino LD, John ER, Chabot RJ, Howard B, Merkin H, et al. The patient state index as an indicator of the level of hypnosis under general anaesthesia. Br J Anaesth. 2004;92:393–9. https://doi.org/10.1093/bja/aeh082.

    Article  CAS  PubMed  Google Scholar 

  15. Drover DR, Lemmens HJ, Pierce ET, Plourde G, Loyd G, Ornstein E, et al. Patient state index: titration of delivery and recovery from propofol, alfentanil, and nitrous oxide anesthesia. Anesthesiology. 2002;97:82–9. https://doi.org/10.1097/00000542-200207000-00012.

    Article  PubMed  Google Scholar 

  16. Chen X, Tang J, White PF, Wender RH, Ma H, Sloninsky A, et al. A comparison of patient state index and bispectral index values during the perioperative period. Anesth Analg. 2002;95:1669–74, table of contents. doi:https://doi.org/10.1097/00000539-200212000-00036

  17. White PF, Tang J, Ma H, Wender RH, Sloninsky A, Kariger R. Is the patient state analyzer with the PSArray2 a cost-effective alternative to the bispectral index monitor during the perioperative period? Anesth Analg. 2004;99:1429–35; table of contents. doi:https://doi.org/10.1213/01.ANE.0000132784.57622.CC

  18. Ramsay MA, Newman KB, Jacobson RM, Richardson CT, Rogers L, Brown BJ, et al. Sedation levels during propofol administration for outpatient colonoscopies. Proc (Bayl Univ Med Cent). 2014;27:12–5. https://doi.org/10.1080/08998280.2014.11929037.

    Article  Google Scholar 

  19. Lee KH, Kim YH, Sung YJ, Oh MK. The patient state index is well balanced for propofol sedation. Hippokratia. 2015;19:235–8.

    CAS  PubMed  PubMed Central  Google Scholar 

  20. Applegate RL 2nd, Lenart J, Malkin M, Meineke MN, Qoshlli S, Neumann M, et al. Advanced monitoring is associated with fewer alarm events during planned moderate procedure-related sedation: A 2-part pilot trial. Anesth Analg. 2016;122:1070–8. https://doi.org/10.1213/ANE.0000000000001160.

    Article  CAS  PubMed  PubMed Central  Google Scholar 

  21. Kuizenga MH, Colin PJ, Reyntjens KMEM, Touw DJ, Nalbat H, Knotnerus FH, et al. Test of neural inertia in humans during general anaesthesia. Br J Anaesth. 2018;120:525–36. https://doi.org/10.1016/j.bja.2017.

    Article  CAS  PubMed  Google Scholar 

  22. Kuizenga MH, Colin PJ, Reyntjens KMEM, Touw DJ, Nalbat H, Knotnerus FH, et al. Population pharmacodynamics of propofol and sevoflurane in healthy volunteers using a clinical score and the patient state index: a crossover study. Anesthesiology. 2019;131:1223–38. https://doi.org/10.1097/ALN.0000000000002966.

    Article  PubMed  Google Scholar 

  23. Caputo TD, Ramsay MA, Rossmann JA, Beach MM, Griffiths GR, Meyrat B, et al. Evaluation of the SEDline to improve the safety and efficiency of conscious sedation. Proc (Bayl Univ Med Cent). 2011;24:200–4. https://doi.org/10.1080/08998280.2011.11928715.

    Article  Google Scholar 

  24. Glass A, Kwiatkowski AW. Power spectral density changes in the EEG during mental arithmetic and eye-opening. Psychol Forsch. 1970;33:85–99.

    Article  CAS  Google Scholar 

  25. Chapman RM, Armington JC, Bragdon HR. A quantitative survey of kappa and alpha EEG activity. Electroencephalogr Clin Neurophysiol. 1962;14:858–68.

    Article  CAS  Google Scholar 

  26. Wan L, Huang H, Schwab N, Tanner J, Rajan A, Lam NB, et al. From eyes-closed to eyes-open: role of cholinergic projections in EC-to-EO alpha reactivity revealed by combining EEG and MRI. Hum Brain Mapp. 2019;40:566–77. https://doi.org/10.1002/hbm.24395.

    Article  PubMed  Google Scholar 

  27. Geller AS, Burke JF, Sperling MR, Sharan AD, Litt B, Baltuch GH, et al. Eye closure causes widespread low-frequency power increase and focal gamma attenuation in the human electrocorticogram. Clin Neurophysiol. 2014;125:1764–73. https://doi.org/10.1016/j.clinph.2014.01.021.

    Article  PubMed  PubMed Central  Google Scholar 

Download references

Acknowledgements

We would like to thank all the volunteers from Austin Health ICU for participating to this study. We would like to thank Rosalba Lembo, MSc (Department of Anesthesia and Intensive Care, IRCCS San Raffaele Scientific Institute) for her help with statistical analysis.

Funding

The study was supported by departmental funds.

Author information

Authors and Affiliations

  1. Department of Intensive Care, Austin Hospital, Heidelberg, VIC, Australia

    Alessandro Belletti, Thummaporn Naorungroj, Fumitaka Yanase, Glenn M. Eastwood & Rinaldo Bellomo

  2. Department of Anaesthesia and Intensive Care, IRCCS San Raffaele Scientific Institute, Milan, Italy

    Alessandro Belletti

  3. Department of Intensive Care, Siriraj Hospital, Mahidol University, Bangkok, Thailand

    Thummaporn Naorungroj

  4. Australian and New Zealand Intensive Care Research Centre, Monash University, Melbourne, VIC, Australia

    Fumitaka Yanase

  5. Department of Anaesthesia, Austin Hospital, Heidelberg, VIC, Australia

    Laurence Weinberg

  6. Department of Surgery, The University of Melbourne, Melbourne, VIC, Australia

    Laurence Weinberg

  7. Department of Medicine, The University of Melbourne, Melbourne, VIC, Australia

    Rinaldo Bellomo

  8. Data Analytics Research and Evaluation Centre, The University of Melbourne and The Austin Hospital, Melbourne, VIC, Australia

    Rinaldo Bellomo

Authors
  1. Alessandro Belletti
    View author publications

    You can also search for this author in PubMed Google Scholar

  2. Thummaporn Naorungroj
    View author publications

    You can also search for this author in PubMed Google Scholar

  3. Fumitaka Yanase
    View author publications

    You can also search for this author in PubMed Google Scholar

  4. Glenn M. Eastwood
    View author publications

    You can also search for this author in PubMed Google Scholar

  5. Laurence Weinberg
    View author publications

    You can also search for this author in PubMed Google Scholar

  6. Rinaldo Bellomo
    View author publications

    You can also search for this author in PubMed Google Scholar

Contributions

AB: this author helped with study design, data collection, data analysis and interpretation, drafted the manuscript, and approved the final version of the manuscript. TN: this author helped with data collection, data analysis, critically reviewed the manuscript, and approved the final version of the manuscript. FY: this author helped with data collection, data analysis, and critically reviewed the manuscript, and approved the final version of the manuscript. GME: this author helped with study design and critically reviewed the manuscript. LW: this author helped with study design, data interpretation and critically reviewed the manuscript, and approved the final version of the manuscript. RB: this authors helped with study design, data analysis and interpretation, and drafted the manuscript, and approved the final version of the manuscript.

Corresponding author

Correspondence to Alessandro Belletti.

Ethics declarations

Conflict of interest

None.

Ethical approval

The study was approved by human research ethics committee (Austin Health Human Research Ethics Committee, protocol no. HREC/54263/Austin-2019, date of approval 26th August 2019, principal investigator Prof. Bellomo). The study was performed in compliance with the Helsinki Declaration, and all participants provided prior written informed consent.

Additional information

Publisher's Note

Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Rights and permissions

Reprints and permissions

About this article

Check for updates. Verify currency and authenticity via CrossMark

Cite this article

Belletti, A., Naorungroj, T., Yanase, F. et al. Normative values for SedLine-based processed electroencephalography parameters in awake volunteers: a prospective observational study. J Clin Monit Comput 35, 1411–1419 (2021). https://doi.org/10.1007/s10877-020-00618-4

Download citation

  • Received:

  • Accepted:

  • Published:

  • Issue Date:

  • DOI: https://doi.org/10.1007/s10877-020-00618-4

Keywords

Search

Navigation