More than 60,000 patients in the U.S. receive general anesthesia every day. But despite the fact that anaesthesia drugs, like ether, have been around for more than 150 years, it's really only been in the past decade or so that we've gained a better understanding of how they work.
Dr. Emery Brown, director of the Harvard-MIT Health Sciences and Technology Program, describes general anaesthesia as a combination of five phenomena: unconsciousness, amnesia, loss of pain sensation, immobility, and yet, physiological stability. Perhaps most amazingly, it's totally reversible.
It might seem that accomplishing all that would require shutting down a lot of brain activity, but Brown says that what anaesthetics actually do is create a whole new kind of brain activity, called oscillations. The oscillations, or brain waves, produced during anaesthesia act like a jamming device, blocking and drowning out normal communications in the brain.
Understanding more about how anaesthesia works could help doctors devise new anaesthetics and better tailor anaesthesia to individual patients. Eventually, Brown says he'd like to see anaesthesia with no lingering side-effects - so that patients wake up feeling like they're picking up exactly where they left off.