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 (24) Citing Articles via Google Scholar Google Scholar Articles by Nieuwenhuijs, D. Articles by Dahan, A. Search for Related Content PubMed PubMed Citation Articles by Nieuwenhuijs, D. Articles by Dahan, A. Related Collections Monitoring (Non-cardiac)

---

TECHNOLOGY, COMPUTING, AND SIMULATION

Bispectral Index Values and Spectral Edge Frequency at Different Stages of Physiologic Sleep

Diederik Nieuwenhuijs, MD^*, Emma L. Coleman, BSc, Neil J. Douglas, FRCP, Gordon B. Drummond, FRCA, and Albert Dahan, MD PhD^*

*Department of Anesthesiology, Leiden University Medical Center, Leiden, The Netherlands; Scottish National Sleep Laboratory; and Department of Anaesthesia, Critical Care and Pain Medicine, Royal Infirmary, Edinburgh, United Kingdom

Address correspondence and reprint requests to Dr. D. Nieuwenhuijs, Department of Anesthesiology, Leiden University Medical Center (P5-Q) PO Box 9600, 2300 RC Leiden, The Netherlands. Address e-mail to djfn{at}worldonline.nl

Bispectral index (BIS) and spectral edge frequency (SEF) are used as measures of depth of anesthesia and sedation. We tested whether these signals could predict physiologic sleep stages, by taking processed electroencephalogram measurements and recording full polysomnography through a night’s sleep in 10 subjects being investigated for mild sleep apnea/hypopnea syndrome. Computerized polysomnograph signals were analyzed manually according to standard criteria, classifying each 30-s epoch as a specific sleep stage. The BIS and SEF values were taken at the end of each period of sleep when the same stage had lasted for at least 2 min. Before sleep, median values for BIS were 97 ± 12.1 and for SEF 23 ± 4.2 Hz. After sleep initiation, the median BIS values for arousal, light, slow wave, and rapid eye movement sleep were 67 ± 20.2, 50 ± 16.5, 42 ± 11.2, and 48 ± 7.1, respectively, and the median SEF values were 20 ± 4.7, 15 ± 3.6, 10 ± 2.6, and 19 ± 4.1 Hz, respectively. Although both BIS and SEF decreased with increasing sleep depth, the distribution of values at each sleep depth was considerable, with overlap between each sleep stage. Neither BIS nor SEF reliably indicated conventionally determined sleep stages. In addition, the response of the BIS was slow and patients could arouse with low BIS values, which then took some time to increase.

IMPLICATIONS: Although computer processing of the electroencephalogram can provide an adequate index of depth of anesthesia, the same processing cannot reliably convey depth of natural sleep. At each sleep stage, the output signal has a wide range of possible values.

This article has been cited by other articles:

				C. Bennett, L. J. Voss, J. P. M. Barnard, and J. W. Sleigh Practical Use of the Raw Electroencephalogram Waveform During General Anesthesia: The Art and Science Anesth. Analg., August 1, 2009; 109(2): 539 - 550. [Abstract] [Full Text] [PDF]

				A. A. Dahaba, G. X. Xu, Q. H. Liu, J. X. Xue, and H. Metzler Bispectral Index Monitoring of a Narcolepsy-Cataplexy Episode During Regional Anesthesia Anesth. Analg., February 1, 2009; 108(2): 613 - 615. [Abstract] [Full Text] [PDF]

				K. E. Kotliar, B. Mucke, W. Vilser, R. Schilling, and I. M. Lanzl Effect of Aging on Retinal Artery Blood Column Diameter Measured along the Vessel Axis Invest. Ophthalmol. Vis. Sci., May 1, 2008; 49(5): 2094 - 2102. [Abstract] [Full Text] [PDF]

				A. Lamas, J. Lopez-Herce, L. Sancho, S. Mencia, A. Carrillo, M. J. Santiago, and V. Martinez Bispectral Index and Middle Latency Auditory Evoked Potentials in Children Younger Than Two-Years-Old Anesth. Analg., February 1, 2008; 106(2): 426 - 432. [Abstract] [Full Text] [PDF]

				A A Dahaba, H C Worm, S M Zhu, F P Bao, A Salah, S Zakaria, H Bornemann, V Stadlbauer, P H Rehak, H Metzler, et al. Sensitivity and specificity of bispectral index for classification of overt hepatic encephalopathy: a multicentre, observer blinded, validation study Gut, January 1, 2008; 57(1): 77 - 83. [Abstract] [Full Text] [PDF]

				R. S. Howard, J. J. Finneran, and S. H. Ridgway Bispectral index monitoring of unihemispheric effects in dolphins. Anesth. Analg., September 1, 2006; 103(3): 626 - 632. [Abstract] [Full Text] [PDF]

				M. M. J. De Jong, S. M. Burns, M. L. Campbell, M. Chulay, M. J. Grap, L. N.B. Pierce, and T. Simpson Development of the American Association of Critical-Care Nurses' Sedation Assessment Scale for Critically Ill Patients Am. J. Crit. Care., November 1, 2005; 14(6): 531 - 544. [Abstract] [Full Text] [PDF]

				F. Benini, M. Trapanotto, S. Sartori, A. Capretta, D. Gobber, C. Boniver, and F. Zacchello Analysis of the Bispectral Index During Natural Sleep in Children Anesth. Analg., September 1, 2005; 101(3): 641 - 644. [Abstract] [Full Text] [PDF]

				R. Soto, T. C. Nguyen, and R. A. Smith A Comparison of Bispectral Index and Entropy, or How to Misinterpret Both Anesth. Analg., April 1, 2005; 100(4): 1059 - 1061. [Abstract] [Full Text] [PDF]

				T. Nishiyama, T. Matsukawa, and K. Hanaoka A Comparison of the Clinical Usefulness of Three Different Electroencephalogram Monitors: Bispectral Index, Processed Electroencephalogram, and Alaris Auditory Evoked Potentials Anesth. Analg., May 1, 2004; 98(5): 1341 - 1345. [Abstract] [Full Text] [PDF]

				S. J. Barker Too Much Technology? Anesth. Analg., October 1, 2003; 97(4): 938 - 939. [Full Text] [PDF]