A preliminary naturalistic study of low-dose ketamine for depression and suicide ideation in the emergency department

Abstract

Background Rapid-onset antidepressants could have important clinical impact if their benefits extended to ED patients. We examined preliminary feasibility, tolerability and efficacy of single-dose IV ketamine in depressed ED patients with suicide ideation (SI). Methods Fourteen depressed ED patients with SI received a single IV bolus of ketamine (0.2 mg/kg) over 1–2 minutes. Patients were monitored for 4 hours, then re-contacted daily for 10 days. Treatment response and time to remission were evaluated using the Montgomery-Asberg Depression Rating Scale (MADRS) and Kaplan Meier survival analysis, respectively. Results Brief Psychiatric Rating Scale and Young Mania Rating Scale scores transiently increased in two subjects, consistent with ketamine's cognitive/behavioral effects in other populations. Mean MADRS scores fell significantly from 40.4 (SEM:1.8) at baseline to 11.5 (2.2) at 240 minutes. Median time to MADRS score ≤10 was 80 minutes (Interquartile Range: 0.67–24 hours). Suicide ideation scores (MADRS item 10) decreased significantly from 3.9 (SEM:0.4) at baseline to 0.6 (SEM:0.2) at 40 minutes post-administration, with improvements sustained over 10 days. Conclusions These data provide preliminary, open-label support for the feasibility and efficacy of ketamine as a rapid-onset antidepressant in the ED.