Rethinking General Anesthesia

Abstract

General anesthesia is a drug-induced, reversible condition comprised of five behavioral states: unconsciousness, amnesia (loss of memory), antinociception (loss of pain sensation), akinesia (immobility), and hemodynamic stability with control of the stress response. Our work shows that a primary mechanism through which anesthetics create these altered states of arousal is by initiating and maintaining highly structured oscillations. These oscillations impair communication among brain regions. We illustrate this effect by presenting findings from our human and non-human primate studies using high-density EEG recordings and intracranial recordings. These studies have allowed us to give a detailed characterization of the neurophysiology of loss and recovery of consciousness due to propofol, and more recently ketamine. We show how these dynamics change systematically with different anesthetic classes and with age. As a consequence, we have developed a principled, neuroscience-based paradigm for using the EEG to monitor the brain states of patients receiving general anesthesia. We demonstrate that the state of general anesthesia can be rapidly reversed by activating specific brain circuits. Finally, we demonstrate that the state of general anesthesia can be controlled using closed-loop feedback control systems.  The success of our research has depended critically on tight coupling of experiments, signal processing research and mathematical modeling.

Bio

Dr. Brown’s research is in the areas of Computational Neuroscience, Anesthesiology, and statistical methods for neuroscience data analysis. He made fundamental contributions to measuring time on the human biological clock, deciphering brain signals, and to the nature of general anesthesia.

In addition to his professorial positions, Dr. Brown serves as the Director of the Neuroscience Statistics Research Laboratory at the Massachusetts Institute of Technology, the co-director of the Harvard-MIT Division of Health Sciences and Technology, and an associate director of MIT’s Institute for Medical Engineering & Science. He is also a practicing anesthesiologist at MGH.

Dr. Brown is a member of the National Academy of Sciences, the National Academy of Medicine, and the National Academy of Engineering. He is also a fellow of the IEEE, the American Association for the Advancement of Science, the American Academy of Arts Sciences, and the National Academy of Inventors.

He has received numerous awards, including an NIH Director’s Pioneer Award, an NIH Director’s Transformative Research Award, the Sacks Prize from the National Institute of Statistical Science, a Guggenheim Fellowship in Applied Mathematics, the American Society of Anesthesiologists Excellence in Research Award, the Dickson Prize in Science, the Swartz Prize for Theoretical and Computational Neuroscience, the Pierre Galletti Award, and a Doctor of Science Honoris Causa from the University of Southern California.

Dr. Brown received his B.A. in Applied Mathematics (magna cum laude) from Harvard College, his M.A. and Ph.D. in statistics from Harvard University and his M.D. (magna cum laude) from Harvard Medical School. Professor Brown completed his internship in internal medicine at the Brigham and Women’s Hospital and his anesthesiology residency at MGH.

Questions may be directed to ECE Alumni Engagement and Events Manager Ann Stals (amriggs).

This event is being offered hybrid. Livestream of the presentation will be shown in the Johnson rooms, third floor, Lurie Engineering Center (U-M North Campus). Zoom information will be shared via email and can be requested from Ann Stals (amriggs).