Results

Seventeen RCTs (n = 1,035) compared ketamine alone or ketamine plus other anesthetic drugs (n = 557) with other anesthetic agents (n = 478) in MDD patients who received ECT. Ketamine+other anesthetic drugs was superior in improving depressive symptoms over other anesthetic medications at early study time point, but not at post-ECT or end of study time points. Ketamine alone was not more efficacious in treating depressive symptoms than other anesthetic drugs at early study, post-ECT and end of study time points. Sensitivity analysis and 19 of the 20 subgroup analyses also confirmed the lack of significance of these findings. Eleven RCTs testing the effects of ketamine on neurocognitive functions with various test batteries found mixed results. Ketamine alone significantly increased blood pressure more than other anesthetic drugs in MDD treated with ECT.