Randomized Controlled Trial Multicenter Study
What's the story here?
Growing evidence points to significant anti-depressant effects of several anesthetic agents, including ketamine, nitrous oxide, propofol and isoflurane. These may provide avenues for use as novel antidepressants or lead to development of new agents, supplanting other therapies such as ECT.
Why is this important?
Major depression and its consequences contributes to significant disease burden worldwide. Depression prevalence is increasing globally, with one third suffering treatment-resistant depression, unresponsive to modern antidepressant drugs.
Isoflurane when administered to achieve burst suppression (1.5-2 MAC) may have antidepressant effects in 75% of those treated, and achieved full remission in 50% in one 2013 study, comparable to ECT but with fewer cognitive side effects.
N2O use in one small pilot study resulted in depression improvement, likely through similar mechanisms as ketamine. Similarly, propofol-induced burst suppression has also shown an antidepressant effect similar in magnitude to isoflurane.
Bottom line: Several anesthetic agents appear to offer significant antidepressant benefits, which may lead to more mainstream use and supplant ECT. Anesthesiologists will be need to be aware of these effects as they become involved in their provision.summary