Commercial brain function monitors for depth of anesthesia have been available for more than 2 decades; there are currently more than 10 devices on the market. Advances in this field are evidenced by updated versions of existing monitors, development of new monitors, and increasing research unveiling the mechanisms of anesthesia on the brain. Electroencephalography signal processing forms an integral part of the technology supporting the brain function monitors for derivation of a depth-of-anesthesia index. This article aims to provide a better understanding of the technology and functionality behind these monitors. This review will highlight the general design principles of these devices and the crucial stages in electroencephalography signal processing and classification, with a focus on the key mathematical techniques used in algorithm development for final derivation of the index representing anesthetic state. We will briefly discuss the advantages and limitations of this technology in the clinical setting as a tool in our repertoire used for optimizing individualized patient care. Also included is a table describing 10 available commercial depth-of-anesthesia monitors.
Accepted for publication June 5, 2017.
Funding: B.G.F. receives funding from the Foundation for Anesthesia Education and Research.
The authors declare no conflicts of interest.
Reprints will not be available from the authors.
Address correspondence to Brenda G. Fahy, MD, MCCM, Department of Anesthesiology, University of Florida College of Medicine, 1600 SW Archer Rd, P.O. Box 100254, Gainesville, FL 32610. Address e-mail to firstname.lastname@example.org.
© 2017 International Anesthesia Research Society