Testing shows promise for automated anesthesia monitoring, delivery system

Editor’s Note

A new automated delivery system for anesthesia that has been effectively tested in monkeys could eventually be used by doctors to identify and deliver the right dose of drugs in people. The findings appeared October 31 in PNAS (Proceedings of the National Academy of Sciences of the United States of America) Nexus.

Typical anesthetic doses are based on body measurements like weight and age. However, researchers point out that these calculations are not always effective. As a result, anesthesiologists often administer higher amounts to ensure that patients remain unconscious, then closely monitor their breathing and heart rates. For the study, they developed a device to do that monitoring work.

This device combines brain-monitoring medical equipment with computer-based algorithms to determine how the body processes the drug Propofol. Every 20 seconds, the machine calculates how much drug is needed to maintain a preset level of brain activity that, according to the results of previous work, is indicative of unconsciousness in macaque monkeys.

In studies with two monkeys, the system accurately shifted the macaques between a lighter sedation and a deeper sleep, lasting 40 or 45 minutes, via an automated delivery system. Researchers plan to expand to experiments with more animals and ultimately switch from implanted electrodes to EEG electrodes that attach to the scalp.