Researchers have found that administering isoflurane, an inhaled anesthetic agent used during surgery, is as effective in treating severe depression as electroconvulsive therapy. Treatment at the University of Utah consisted of either eight to 12 treatments of bifrontal ECT or 10 isoflurane treatments over a period of 2.5 to three weeks. Patients receiving isoflurane were dosed to EEG isoelectricity (suppression of electrical activity in the brain) for 15 minutes at each treatment. The dose used was initially 2.5 times the age-adjusted minimum alveolar concentration and then adjusted to assure greater than 80% burst suppression ratio by EEG. One patient who received isoflurane dropped out because of anxiety, according to the researchers. Aside from the efficacy of reducing depressive symptoms, anesthetic gas did not cause some of the side effects of ECT including memory loss. Patients treated with isoflurane showed a much more rapid recovery of cognitive function than ECT.

“Patients who come to ECT are in a crisis and often functioning at a low level due to the severity of their depression. Since almost 4 million people with major depression in the United States are treated ineffectively each year, this could potentially help hundreds of thousands of patients,” said lead author Scott Tadler, MD, assistant professor of anesthesiology at the University of Utah.

Anesthesiology News
JANUARY 2012 | VOLUME: 38:01
Volatile Anesthetic Shows Promise for Treating Major Depression
Small study hints at benefits of isoflurane over electroshock
by Jennifer Hanawald