Ketamine as the anaesthetic for electroconvulsive therapy: the KANECT randomised controlled trial

Ketamine as an Alternative Anesthetic for Augmenting Seizure Durations During Electroconvulsive Therapy: A Retrospective Observational Study

OBJECTIVE

Electroconvulsive therapy (ECT) is highly effective for severe psychiatric disorders; however, short seizure durations may lead to ineffective therapy. This retrospective study aimed to examine the risks and benefits of switching to ketamine anesthesia to augment seizure durations during an acute course of ECT.

METHODS

We included 33 patients who underwent ketamine anesthesia due to suboptimal seizures during an acute course of ECT. We assessed seizure duration, stimulus dose, hemodynamic variability, and postseizure complications before and after switching to ketamine.

RESULTS

Age was significantly associated with suboptimal seizures during ECT ( P = 0.040). After switching to ketamine, 32 patients (97%) experienced prolonged seizure duration. Ketamine significantly prolonged both electroencephalogram and motor seizure durations with a mean difference of 34.6 seconds (95% confidence interval [CI], 26.4-42.7 seconds; P < 0.001) and 26.6 seconds (95% CI, 19.6-33.6 seconds; P < 0.001), respectively. It also significantly reduced stimulus dose (mean difference, -209.5 mC [95% CI, -244.9 to -174.1 mC]; P < 0.001). In addition, maximum changes in systolic blood pressure and heart rate during ECT sessions significantly increased with ketamine (mean difference, 27.2 mm Hg [95% CI, 12.0-42.4 mm Hg; P = 0.001]; 25.7 beats per minute [95% CI, 14.5-36.8 beats per minute; P < 0.001], respectively). Patients reported more headaches with ketamine ( P = 0.041).

CONCLUSIONS

Our results provide evidence that ketamine as an alternative anesthetic can augment seizure durations in specific patients experiencing suboptimal seizures during an acute course of ECT. However, its use requires greater attention to circulatory management and postseizure complications.

Ketamine and electroconvulsive therapy for severe depression: A network meta-analysis of efficacy and safety

BACKGROUND

Ketamine, electroconvulsive therapy (ECT), and their combination are effective for treating severe depression, but few large-scale studies have compared these.

METHODS

We searched databases for randomized controlled trials (RCTs) using ketamine, ECT, ketamine + ECT, or placebo for severe depression. Standardized measures were efficacy outcomes. Risk of bias was assessed. Stata and ADDIS were used for network meta-analysis (NMA) comparing efficacy and adverse reactions post-treatment. This study was registered on PROSPERO (CRD42023476740).

RESULTS

17 RCTs with 1370 patients were included. NMA showed ECT and ketamine improved Hamilton Depression Rating Scale (HDRS) versus placebo; other comparisons not significant. Rank probabilities showed highest probability for ECT, followed by ketamine + ECT, ketamine, placebo. No differences in Montgomery-Asberg Depression Rating Scale (MADRS); highest rank probability again for ECT, followed by ketamine + ECT, ketamine, placebo.

CONCLUSIONS

Analysis suggests ECT superior to ketamine and their combination for improving depressive severity, but individualized treatment selection warranted. Higher adverse reactions with ketamine + ECT need further study for optimized combined use.

Recurrent Serotonin Syndrome After Ketamine-assisted Electroconvulsive Therapy: A Case Report and Review of the Literature

Serotonin (5-HT) syndrome (SS) consists of changes in mental status as well as autonomic and neuromuscular changes. Though not well understood, serotonergic pathways have been implicated in the mechanism of action of electroconvulsive therapy (ECT). Ketamine has been used as an induction agent in ECT and as therapy for treatment-resistant depression. Utilizing a case report and literature review, we explored the underlying serotonergic mechanisms of ECT and ketamine by which a syndrome of serotonin toxicity may be precipitated. We describe the case of a 72-year-old woman who developed recurrent SS on 2 occasions in similar circumstances involving the administration of ketamine for ECT. In our literature review, we found 5 cases in which SS was associated with ECT and 1 case linking ketamine to SS. There is emerging evidence that the mechanism of ECT involves 5-HT1A and 5-HT2A receptors, the same receptors that are involved in SS. ECT can transiently increase the permeability of the blood-brain barrier, leading to increased levels of antidepressants in the brain. ECT can, therefore, enhance 5-HT transmission and the likelihood of SS in the presence of serotonergic agents. The effect of ketamine on 5-HT transmission is mediated by the glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor. Ketamine increases α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid activity in the medial prefrontal cortex, which leads to downstream 5-HT release through glutamate. Through this mechanism, ketamine can increase 5-HT transmission, leading to SS. To our knowledge, this is the only case report of recurrent SS with concurrent use of ECT and ketamine. As ketamine is frequently used in ECT and many patients undergoing ECT are on serotonergic medications, it is important to recognize ketamine as a potential risk factor for SS. There is no evidence for added efficacy when combining ECT and ketamine. Thus, one should proceed with caution when combining these treatments. The burgeoning use of ketamine in ambulatory settings makes it necessary to elucidate the risks, which we discuss further. More research is needed into the mechanisms of ketamine and ECT, specifically how the combination of these treatments influence 5-HT levels.

Perspectives in treatment-resistant depression: esketamine and electroconvulsive therapy

Modern electroconvulsive therapy (ECT) and the approval of nasal esketamine for clinical use have significantly improved the approach to treatment-resistant depression (TRD), which is defined as non-response to at least two different courses of antidepressants with verified adherence to treatment, adequate dosage, and duration of treatment. The goal of this literature review is to present the newest evidence regarding efficacy and safety. Furthermore, we aim to provide an overview of future perspectives in this field of research, for example, regarding structural and molecular effects. Both treatment methods will be critically evaluated for their individual advantages, disadvantages, and response rates. Firstly, we will discuss the well-established method of ECT and its different treatment modalities. Secondly, we will discuss the properties of ketamine, the discovery of its antidepressive effects and the route to clinical approval of the esketamine nasal spray. We will comment on research settings which have evaluated intravenous ketamine against ECT. The decision-making process between esketamine nasal spray or ECT should include the assessment of contraindications, age, severity of disease, presence of psychotic symptoms, patient preference and treatment accessibility. We conclude that both treatment options are highly effective in TRD. If both are indicated, pragmatically esketamine will be chosen before ECT; however, ECT studies in ketamine non-responders are missing.

Efficacy and safety of ketamine-assisted electroconvulsive therapy in major depressive episode: a systematic review and network meta-analysis

OBJECTIVE

To meta-analyze clinical efficacy and safety of ketamine compared with other anesthetic agents in the course of electroconvulsive therapy (ECT) in major depressive episode (MDE).

METHODS

PubMed/MEDLINE, Cochrane Library, Embase, GoogleScholar, and US and European trial registries were searched from inception through May 23, 2023, with no language limits. We included RCTs with (1) a diagnosis of MDE; (2) ECT intervention with ketamine and/or other anesthetic agents; and (3) measures included: depressive symptoms, cognitive performance, remission or response rates, and serious adverse events. Network meta-analysis (NMA) was performed to compare ketamine and 7 other anesthetic agents. Hedges' g standardized mean differences (SMDs) were used for continuous measures, and relative risks (RRs) were used for other binary outcomes using random-effects models.

RESULTS

Twenty-two studies were included in the systematic review. A total of 2322 patients from 17 RCTs were included in the NMA. The overall pooled SMD of ketamine, as compared with propofol as a reference group, was -2.21 (95% confidence interval [CI], -3.79 to -0.64) in depressive symptoms, indicating that ketamine had better antidepressant efficacy than propofol. In a sensitivity analysis, however, ketamine-treated patients had a worse outcome in cognitive performance than propofol-treated patients (SMD, -0.18; 95% CI, -0.28 to -0.09). No other statistically significant differences were found.

CONCLUSIONS

Ketamine-assisted ECT is tolerable and may be efficacious in improving depressive symptoms, but a relative adverse impact on cognition may be an important clinical consideration. Anesthetic agents should be considered based on patient profiles and/or preferences to improve effectiveness and safety of ECT use.

Comparative efficacy and tolerability of different anesthetics in electroconvulsive therapy for major depressive disorder: A systematic review and network meta-analysis

Electroconvulsive therapy (ECT) is one of the most effective treatments for major depressive disorder. Modern ECT is conducted with anesthesia, however, the optimal anesthetic agent for ECT is yet to be understood. This study is aimed to compare the effects of different anesthetic agents on antidepressant efficacy and tolerability in depressed individuals undergoing ECT. We searched MEDLINE, EMBASE, the CENTRAL and PsycINFO for randomized controlled trials from database inception until Nov 13, 2022 (PROSPERO: CRD42022375407). Global and local inconsistencies, heterogeneity and publication bias were assessed. Rankings were calculated with the surface under the cumulative ranking curve. A total of 33 studies involving 1898 patients were enrolled. Remission rates were higher for ketamine anesthesia as compared to adjunctive ketamine and propofol. In terms of ranking, ketamine was found to be first in terms of response/remission rates and depressive scores after the 1st, 3rd and 6th ECT and at the end of ECT session, while a higher incidence of adverse events was also observed. No significant advantage of any anesthetic was revealed for the cognitive function after ECT. In summary, based on current evidence, no specific anesthetic is recommended for ECT anesthesia. However, despite more side effects, ketamine monoanesthesia seems to reveal a potential benefit in improving antidepressant efficacy of ECT, and further studies are needed to investigate the relationship between anesthetic agents and the therapeutic effect of ECT.

Efficacy and Safety of Ketamine-assisted Electroconvulsive Therapy in Major Depressive Episode: A Systematic Review and Network Meta-Analysis

Objective

To meta-analyze clinical efficacy and safety of ketamine compared with other anesthetic agents in the course of electroconvulsive therapy (ECT) in major depressive episode (MDE).

Methods

PubMed/MEDLINE, Cochrane Library, Embase, GoogleScholar, and US and European trial registries were searched from inception through May 23, 2023, with no language limits. We included RCTs with (1) a diagnosis of MDE; (2) ECT intervention with ketamine and/or other anesthetic agents; and (3) measures included: depressive symptoms, cognitive performance, remission or response rates, and serious adverse events. Network meta-analysis (NMA) was performed to compare ketamine and 7 other anesthetic agents. Hedges' g standardized mean differences (SMDs) were used for continuous measures, and relative risks (RRs) were used for other binary outcomes using random-effects models.

Results

Twenty-two studies were included in the systematic review. A total of 2,322 patients from 17 RCTs were included in the NMA. The overall pooled SMD of ketamine, as compared with a propofol reference group, was -2.21 (95% confidence interval [CI], -3.79 to -0.64) in depressive symptoms, indicating that ketamine had better antidepressant efficacy than propofol. In a sensitivity analysis, however, ketamine-treated patients had a worse outcome in cognitive performance than propofol-treated patients (SMD, -0.18; 95% CI, -0.28 to -0.09). No other statistically significant differences were found.

Conclusions

Ketamine-assisted ECT is tolerable and may be efficacious in improving depressive symptoms, but a relative adverse impact on cognition may be an important clinical consideration. Anesthetic agents should be considered based on patient profiles and/or preferences to improve effectiveness and safety of ECT use.

Ketamine Augmentation of Electroconvulsive Therapy: A Scoping Review of Dose-Dependent Effects in Major Depressive Disorder

Intravenous ketamine infusions in subanesthetic doses have been shown to rapidly alleviate depressive symptoms. However, the efficacy of ketamine as an anesthetic during electroconvulsive therapy (ECT) for major depression has not yet been answered by a large randomized control trial (RCT). This scoping review aims to examine the available literature to determine whether the dose of ketamine used during ECT influences the response to treatment. A literature search was conducted on PubMed to identify all published RCTs within the last 10 years which compared ketamine anesthesia during ECT for major depression with another anesthetic. Studies using low (<0.8 mg/kg) versus high (≥0.8 mg/kg) doses of ketamine during ECT were evaluated for the differences in outcomes using depression rating scales. Studies that examined ketamine as a standalone treatment for depression or focused primarily on the anesthetic benefits of ketamine were excluded from our review. Fifteen studies were utilized for this literature review. Overall, the studies showed inconsistent results in terms of the speed and magnitude of response to ketamine-assisted ECT in patients with major depression. Limitations of the available literature are discussed, including the lack of head-to-head comparisons, differences in methodology, inclusion/exclusion criteria, and primary and secondary endpoints.

The effect of ketamine on cognition, anxiety, and social functioning in adults with psychiatric disorders: A systematic review and meta-analysis

Background

It has been shown that ketamine can improve suicidality and depression. Evidence for other dimensions of psychopathology is lacking. We undertook a systematic review to investigate the effect of ketamine on cognition, anxiety, quality of life, and social functioning in adults with psychiatric disorders.

Methods

PubMed (Medline), Scopus, PsycINFO, and EMBASE were searched up to April 2022. Randomized controlled trials (RCTs) on ketamine [or its S (+) enantiomer] reporting data on cognition, anxiety, quality of life, social functioning in adults with psychiatric disorders were included. Standardized mean difference (SMD) was used for summarizing continuous outcomes.

Results

Twenty-two reports were included in the final selection, of which 20, corresponding to 1,298 participants, were included in the quantitative synthesis. Affective disorders were the predominant diagnostic category. Median follow-up time was 21 days. The evidence was rated moderate to very low. In most trials, ketamine was administered intravenously or as adjuvant to electro-convulsant therapy (ECT). Only 2 trials of intranasal esketamine were identified. The effect of ketamine on depression was confirmed (SMD: -0.61 [95% CI: -1.06; -0.16]). Furthermore, by pooling results of 6 RCTs, ketamine may be effective in reducing anxiety symptoms (SMD: -0.42 [95% CI: -0.84; 0.003]), particularly when administered not within ECT (5 trials; SMD: -0.58 [95% CI: -1.07; -0.09]). However, there was moderate heterogeneity of results. Patients treated with ketamine also had an improvement in social functioning (SMD: -0.31 [95% CI: -0.52; -0.10]), although the estimate was based only on 2 studies. No difference to comparators was found with respect to cognition and quality of life.

Conclusion

Alongside the antidepressant effect, ketamine may also improve anxiety and social functioning in adults with affective disorders.

Efficacy and safety of racemic ketamine and esketamine for depression: a systematic review and meta-analysis

BACKGROUND

Racemic ketamine and esketamine have demonstrated rapid antidepressant effects. We aimed to review the efficacy and safety of racemic and esketamine for depression.

RESEARCH DESIGN AND METHODS

We conducted a PRISMA-guided review for relevant randomized controlled trials of racemic or esketamine for unipolar or bipolar major depression from database inception through 2021. We conducted random-effects meta-analyses using pooled rate ratios (RRs) and Cohen's standardized mean differences (d) with their 95% confidence intervals (CI).

RESULTS

We found 36 studies (2903 participants, 57% female, 45.1 +/- 7.0 years). Nine trials used esketamine, while the rest used racemic ketamine. The overall study quality was high. Treatment with any form of ketamine was associated with improved response (RR=2.14; 95% CI, 1.72-2.66; I2=65%), remission (RR=1.64; 95% CI, 1.33-2.02; I2=39%), and depression severity (d=-0.63; 95% CI, -0.80 to -0.45; I2=78%) against placebo. Overall, there was no association between treatment with any form of ketamine and retention in treatment (RR=1.00; 95% CI, 0.99-1.01; I2<1%), dropouts due to adverse events (RR=1.56; 95% CI, 1.00-2.45; I2<1%), or the overall number of adverse events reported per participant (OR=2.14; 95% CI, 0.82-5.60; I2=62%) against placebo.

CONCLUSIONS

Ketamine and esketamine are effective, safe, and acceptable treatments for individuals living with depression.

Sex differences in ketamine's therapeutic effects for mood disorders: A systematic review

Replicated clinical trials have demonstrated rapid and robust antidepressant effects with ketamine in treatment resistant mood disorders. Sex (biological) and gender differences in therapeutic effects for any new intervention is an important consideration, however, the differential efficacy, safety and tolerability of ketamine in males versus females remains underexplored. The objective of the present systematic review is to identify and qualitatively synthesize all published clinical studies relevant to the sex differential effects of ketamine for mood disorders. A systematic search of PubMed, Medline, and PsycInfo from inception until January 20, 2021, yielded 27 reports including 1715 patients (742 males and 973 females) that met inclusion criteria. Results from the vast majority of studies (88.8%) do not support significant sex differences in antidepressant response, tolerability or safety of ketamine. Nine (33.3%) of the reports included a bioanalytical component in the analysis and only one reported on sex differences. Evidence from the present review does not support clinically or statistically significant sex differences in therapeutic effects with ketamine. Nevertheless, future studies should continue to consider sex and biological sex differences in study design and data analytic plans.

The concentration of MMP-9 and the effects of intravenous anaesthetics on the efficacy of electroconvulsive therapy in patients with drug-resistant depression

Introduction: This study attempts to assess the concentration of intracellular matrix metalloproteinase (MMP-9) before and after the treatment of depressive episodes with ECT therapy and also to correlate the concentration of this enzyme with the use of commonly used general anaesthetics.

Materials and methods: The study group comprised of 37 patients hospitalized in the Department of Adult Psychiatry in Poznan, with a diagnosis of episodes of drug-resistant depression during the course of bipolar and unipolar affective disorders, and who were being treated using electroconvulsive therapy. For the purpose of inducing anaesthesia during the procedure propofol was used in 10 cases, thiopental in 9 cases. Propofol was alternated with ketamine in a further 10 cases and thiopental was alternated with ketamine in another 9 cases. In order to assess the intensity of depression symptoms, the 17 point Hamilton depression scale was used, immediately before commencing ECT therapy, and one day after its completion. The serum concentration of MMP-9 was determined before and after the series of ECT treatments. In order to assess the serum concentration of MMP-9, an ELISA immunoenzymatic method was applied.

Results: In this study, a significant reduction of MMP-9 concentration was noted after therapy, relative to the starting concentration, in the serum of patients suffering from depressive episodes resulting from either unipolar or bipolar affective disorders. These results correlated with improved psychiatric state, as assessed by the Hamilton scale. A significantly lower MMP-9 concentration was noted in the serum of patients given alternating thiopental and ketamine anaesthesia.

Conclusions: This study suggests the importance of the enzyme as a biological marker for the effective treatment of depression. Furthermore, the choice of general anaesthetic applied during ECT also plays a role.

Ketamine for the treatment of mental health and substance use disorders: comprehensive systematic review

BACKGROUND

In the past two decades, subanaesthetic doses of ketamine have been demonstrated to have rapid and sustained antidepressant effects, and accumulating research has demonstrated ketamine's therapeutic effects for a range of psychiatric conditions.

AIMS

In light of these findings surrounding ketamine's psychotherapeutic potential, we systematically review the extant evidence on ketamine's effects in treating mental health disorders.

METHOD

The systematic review protocol was registered in PROSPERO (identifier CRD42019130636). Human studies investigating the therapeutic effects of ketamine in the treatment of mental health disorders were included. Because of the extensive research in depression, bipolar disorder and suicidal ideation, only systematic reviews and meta-analyses were included. We searched Medline and PsycINFO on 21 October 2020. Risk-of-bias analysis was assessed with the Cochrane Risk of Bias tools and A Measurement Tool to Assess Systematic Reviews (AMSTAR) Checklist.

RESULTS

We included 83 published reports in the final review: 33 systematic reviews, 29 randomised controlled trials, two randomised trials without placebo, three non-randomised trials with controls, six open-label trials and ten retrospective reviews. The results were presented via narrative synthesis.

CONCLUSIONS

Systematic reviews and meta-analyses provide support for robust, rapid and transient antidepressant and anti-suicidal effects of ketamine. Evidence for other indications is less robust, but suggests similarly positive and short-lived effects. The conclusions should be interpreted with caution because of the high risk of bias of included studies. Optimal dosing, modes of administration and the most effective forms of adjunctive psychotherapeutic support should be examined further.

Ketamine in depression and electroconvulsive therapy

PURPOSE OF REVIEW

The antidepressant effect of subanesthetic doses of ketamine was recognized 20 years ago. This review briefly summarizes the current understanding of the antidepressant mechanisms and the available clinical research on the use of racemic ketamine and enantiomer esketamine for depression.

RECENT FINDINGS

The antidepressant effect of subanesthetic doses of ketamine is currently considered to be predominantly mediated by improved neuroplasticity in cortico-limbic areas in the brain. Single dose of 0.5 mg/kg of ketamine infused intravenously over 40 min, or single intranasal dose of esketamine cause rapid antidepressant and antisuicidal effects within hours of administration, and the antidepressant effect may last up to a week. Repeated administration of nasal spray esketamine is considered to prevent relapse of depression. Longitudinal studies are currently insufficient. When used in various doses for anesthetic induction for electroconvulsive therapy, ketamine improves seizure quality and may possibly diminish posttherapy cognitive impairment.

SUMMARY

A rapid onset antidepressive effect of ketamine and esketamine has been proven conclusively. The results of extensive basic science research of the mechanism of action of low-dose ketamine doses has led to an alternative hypothesis of the pathophysiology of depression and the development of a novel neurotrophic concept of depression. Further longitudinal studies are warranted to determine the safety and efficacy of repeated administration of ketamine and its analogs to prevent relapse and recurrence of depression.

Ketamine and other glutamate receptor modulators for depression in adults with unipolar major depressive disorder

BACKGROUND

Many studies have recently been conducted to assess the antidepressant efficacy of glutamate modification in mood disorders. This is an update of a review first published in 2015 focusing on the use of glutamate receptor modulators in unipolar depression.

OBJECTIVES

To assess the effects - and review the acceptability and tolerability - of ketamine and other glutamate receptor modulators in alleviating the acute symptoms of depression in people with unipolar major depressive disorder.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL), Ovid MEDLINE, Embase and PsycINFO all years to July 2020.  We did not apply any restrictions to date, language or publication status.

SELECTION CRITERIA

Double- or single-blinded randomised controlled trials (RCTs) comparing ketamine, memantine, esketamine or other glutamate receptor modulators with placebo (pill or saline infusion), other active psychotropic drugs, or electroconvulsive therapy (ECT) in adults with unipolar major depression.

DATA COLLECTION AND ANALYSIS

Three review authors independently identified studies, assessed trial quality and extracted data. The primary outcomes were response rate (50% reduction on a standardised rating scale) and adverse events. We decided a priori to measure the efficacy outcomes at different time points and run sensitivity/subgroup analyses. Risk of bias was assessed using the Cochrane tool, and certainty of the evidence was assessed using GRADE.

MAIN RESULTS

Thirty-one new studies were identified for inclusion in this updated review. Overall, we included 64 studies (5299 participants) on ketamine (31 trials), esketamine (9), memantine (5), lanicemine (4), D-cycloserine (2), Org26576 (2), riluzole (2), atomoxetine (1), basimglurant (1), citicoline (1), CP-101,606 (1), decoglurant (1), MK-0657 (1), N-acetylcysteine (1), rapastinel (1), and sarcosine (1). Forty-eight studies were placebo-controlled, and 48 were two-arm studies. The majority of trials defined an inclusion criterion for the severity of depressive symptoms at baseline: 29 at least moderate depression; 17 severe depression; and five mild-to-moderate depression. Nineteen studies recruited only patients with treatment-resistant depression, defined as inadequate response to at least two antidepressants. The majority of studies investigating ketamine administered as a single dose, whilst all of the included esketamine studies used a multiple dose regimen (most frequently twice a week for four weeks). Most studies looking at ketamine used intravenous administration, whilst the majority of esketamine trials used intranasal routes. The evidence suggests that ketamine may result in an increase in response and remission compared with placebo at 24 hours odds ratio (OR) 3.94, 95% confidence interval (CI) 1.54 to 10.10; n = 185, studies = 7, very low-certainty evidence). Ketamine may reduce depression rating scale scores over placebo at 24 hours, but the evidence is very uncertain (standardised mean difference (SMD) -0.87, 95% CI -1.26 to -0.48; n = 231, studies = 8, very low-certainty evidence). There was no difference in the number of participants assigned to ketamine or placebo who dropped out for any reason (OR 1.25, 95% CI 0.19 to 8.28; n = 201, studies = 6, very low-certainty evidence). When compared with midazolam, the evidence showed that ketamine increases remission rates at 24 hours (OR 2.21, 95% CI 0.67 to 7.32; n = 122,studies = 2, low-certainty evidence). The evidence is very uncertain about the response efficacy of ketamine at 24 hours in comparison with midazolam, and its ability to reduce depression rating scale scores at the same time point (OR 2.48, 95% CI 1.00 to 6.18; n = 296, studies = 4,very low-certainty evidence). There was no difference in the number of participants who dropped out of studies for any reason between ketamine and placebo (OR 0.33, 95% CI 0.05 to 2.09; n = 72, studies = 1, low-certainty evidence). Esketamine treatment likely results in a large increase in participants achieving remission at 24 hours compared with placebo (OR 2.74, 95% CI 1.71 to 4.40; n = 894, studies = 5, moderate-certainty evidence). Esketamine probably results in decreases in depression rating scale scores at 24 hours compared with placebo (SMD -0.31, 95% CI -0.45 to -0.17; n = 824, studies = 4, moderate-certainty evidence). Our findings show that esketamine increased response rates, although this evidence is uncertain (OR 2.11, 95% CI 1.20 to 3.68; n = 1071, studies = 5, low-certainty evidence). There was no evidence that participants assigned to esketamine treatment dropped out of trials more frequently than those assigned to placebo for any reason (OR 1.58, 95% CI 0.92 to 2.73; n = 773, studies = 4,moderate-certainty evidence). We found very little evidence for the remaining glutamate receptor modulators. We rated the risk of bias as low or unclear for most domains, though lack of detail regarding masking of treatment in the studies reduced our certainty in the effect for all outcomes.

AUTHORS' CONCLUSIONS

Our findings show that ketamine and esketamine may be more efficacious than placebo at 24 hours. How these findings translate into clinical practice, however, is not entirely clear. The evidence for use of the remaining glutamate receptor modulators is limited as very few trials were included in the meta-analyses for each comparison and the majority of comparisons included only one study. Long term non-inferiority RCTs comparing repeated ketamine and esketamine, and rigorous real-world monitoring are needed to establish comprehensive data on safety and efficacy.

Low-dose ketamine does not improve the speed of recovery from depression in electroconvulsive therapy: a randomized controlled trial

OBJECTIVE

Electroconvulsive therapy (ECT) is a well-established therapeutic intervention for major depressive disorder. Recent literature has shown that the anesthetic agent ketamine has some antidepressant properties at low doses and may be an alternative therapy for treatment-resistant major depressive disorder. We hypothesized that the use of low-dose ketamine as an anesthetic adjunct in ECT would more rapidly improve depression while maintaining hemodynamic stability than ECT with propofol alone.

METHODS

Institutional ethics approval was obtained, and the use of ketamine in this study was approved by Health Canada. This is a randomized, double-blinded, placebo-controlled trial that involved ketamine administration at 0.5 mg/kg IV in addition to propofol anesthesia for ECT. The primary outcome was the number of ECT treatments required to achieve a 50% reduction in the Montgomery-Asberg Depression Rating Scale (MADRS). Secondary outcomes included the number of ECT treatments required to achieve a 25% reduction in MADRS score, as well as any differences in the Clinical Global Impression Scale for Severity, hemodynamic variables, and seizure duration. Adverse events were recorded for safety assessment.

RESULTS

A total of 45 patients completed the study. No difference was found between groups with respect to the primary or secondary outcomes. The ketamine group showed a trend towards a decreased dose of propofol required to achieve adequate anesthesia. No adverse events were reported.

CONCLUSION

Low-dose ketamine does not improve psychiatric outcomes in the setting of propofol-based anesthesia for ECT. Specifically, ketamine did not reduce the number of ECT sessions necessary to achieve a 50 or 25% reduction in MADRS scores. Reassuringly, the fact that no differences in hemodynamic variables or unexpected adverse events occurred suggests that low-dose ketamine may be safely used in this setting should clinical indications warrant its use.

CLINICAL TRIAL REGISTRATION

ClinicalTrials.gov, NCT02579642.

Effectiveness and Safety of Ketamine for Unipolar Depression: a Systematic Review

Major Depressive Disorder (MDD) is a common psychiatric disorder with major implications for healthcare system and socioeconomic burden. For chronic and treatment-resistant depression, Ketamine has emerged as a possible treatment option. This systematic review explores the evidence for the effectiveness and tolerability of Ketamine in patients with MDD. This systematic review was conducted following the guidelines of Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) checklist. Eight electronic databases were searched by using search terms: (ketamine) AND (trial OR RCT OR clinical-trial) AND (depressive OR depression OR "depressive-disorder"). After a rigorous screening process against the predetermined eligibility criteria, 35 randomized controlled trials (RCTs) were included. Quality assessment of included studies was done by using the Cochrane risk-of-bias tool for RCTs. Thirty-five RCTs are included in this review article with majority of studies from United States, Iran, and China. Intravenous (IV) Ketamine was effective in 70% (21/30) of the included studies whereas oral and Intranasal (IN) Ketamine were effective in two and three studies, respectively. The majority of studies (6/8) using Ketamine as anesthetic agent during electroconvulsive therapy (ECT) failed to show an improvement compared to the participants receiving ECT and placebo. The most common reported side effects were nausea, vomiting, dizziness, diplopia, drowsiness, dysphoria, hallucinations, and confusion. Ketamine is an effective treatment option for patients with MDD with undesirable effects when administered via oral, IV and IN routes. Ketamine agumentation of ECT requires further exploration in well-designed studies with adequate sample size. The short-lived antidepressant effect of Ketamine is a potential limitation, therefore, further studies administering multiple infusions for acute treatment and maintenance are necessary.

The Combination of Propofol and Ketamine Does Not Enhance Clinical Responses to Electroconvulsive Therapy in Major Depression-The Results From the KEOpS Study

Objective

We investigated the clinical effects of the combination of ketamine and propofol as anesthetic agents during electroconvulsive therapy (ECT) in patients with uni- or bipolar major depressive episodes. We hypothesized that ketamine may confer short- and long- term advantages in improving depressive symptoms at the early stages of ECT.

Methods

In a randomized placebo-controlled trial, remission rates after 4 and 8 weeks of ECT were compared between patients who were randomly allocated to receive either the combination of ketamine (0.5 mg/kg) + propofol (n= 11) or placebo + propofol (n = 16). Depressive symptoms were assessed weekly using the Montgomery-Åsberg Depression Rating Scale (MADRS); ECT sessions were administered twice per week for a maximum of 8 weeks (16 sessions).

Results

After 4 weeks, we observed significantly fewer remitters (MADRS score < 10) in the ketamine + propofol group (0/11; 0%) than in the placebo + propofol group (5/16; 31%; χ² = 4.22; p = 0.040). No significant difference was observed between the two groups regarding the number of patients who achieved remission weekly throughout the study period (Chi² = 3.588; p = 0.058). The mean duration of seizures was significantly shorter in the ketamine + propofol group than in the placebo + propofol group.

Conclusions

The results from the current study corroborated results from previously published studies and did not support the use of the combination of ketamine + propofol as an anesthetic agent for ECT in patients with major depressive episodes in clinical settings.

Effects of ketamine in electroconvulsive therapy for major depressive disorder: meta-analysis of randomised controlled trials

Background

The use of ketamine in electroconvulsive therapy (ECT) has been examined in the treatment of major depressive disorder (MDD); however, there has been no systematic review and meta-analysis of related randomised controlled trials (RCTs).

Aim

To examine the efficacy and safety of ketamine augmentation of ECT in MDD treatment.

Methods

Two reviewers searched Chinese (China National Knowledge Infrastructure and Wanfang) and English (PubMed, PsycINFO, Embase and Cochrane Library) databases from their inception to 23 July 2019. The included studies' bias risk was evaluated using the Cochrane risk of bias assessment tool. The primary outcome of this meta-analysis was improved depressive symptoms at day 1 after a single ECT treatment session. Data were pooled to calculate the standardised mean difference and risk ratio with their 95% CIs using RevMan V.5.3. We used the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) approach to assess the whole quality of evidence.

Results

Four RCTs (n = 239) compared ketamine alone or ketamine plus propofol (n = 149) versus propofol alone (n = 90) in patients with MDD who underwent a single ECT session. Three RCTs were considered as unclear risk with respect to random sequence generation using the Cochrane risk of bias. Compared with propofol alone, ketamine alone and the combination of ketamine and propofol had greater efficacy in the treatment of depressive symptoms at days 1, 3 and 7 after a single ECT session. Moreover, compared with propofol alone, ketamine alone and the combination of ketamine and propofol were significantly associated with increased seizure duration and seizure energy index. Compared with propofol, ketamine alone was significantly associated with increased opening-eye time. Based on the GRADE approach, the evidence level of primary and secondary outcomes ranged from very low (26.7%, 4/15) to ‘low’ (73.3%, 11/15).

Conclusion

Compared with propofol, there were very low or low evidence levels showing that ketamine alone and the combination of ketamine and propofol appeared to rapidly improve depressive symptoms of patients with MDD undergoing a single ECT session. There is a need for high-quality RCTs.

Effects of Ketamine Anesthesia on Efficacy, Tolerability, Seizure Response, and Neurocognitive Outcomes in Electroconvulsive Therapy: A Comprehensive Meta-analysis of Double-Blind Randomized Controlled Trials

Electroconvulsive therapy (ECT) remains the most effective treatment for major depressive disorder. Ketamine is an anesthetic gaining attention for its rapid antidepressant effect. Numerous randomized controlled trials have investigated the effect of ketamine anesthesia in ECT on various clinical outcomes. Previous systematic reviews have not found benefit for overall depression response, although some have found evidence of benefit early in the ECT course. Clear quantitative conclusions have not been established regarding other outcomes, particularly while only using data from high-quality studies. We aimed to examine all data from double-blind randomized controlled trials comparing ketamine to other anesthetics via meta-analysis, to make recommendations regarding ECT practice and future research. Data were extracted for depressive symptoms, seizure duration and electrical dose, neuropsychological performance, and adverse effects. Effect sizes were calculated using Hedge's g and odds ratios. Eighteen studies (n = 915) were included in the meta-analysis. Ketamine was not found to enhance improvement of depressive symptoms, either early in ECT course or at end of study. Ketamine had a large effect on increasing seizure duration both overall (Hedge's g = 0.71, P = 0.038) and in the subgroup receiving ketamine in combination with another anesthetic (Hedge's g = 0.78, P < 0.01), and on decreasing electrical dose (Hedge's g = 1.98, P = 0.039). There was no significant effect of ketamine on any individual neuropsychological domain. Ketamine was not associated with increased adverse effects, except for hypertension in patients receiving ketamine monotherapy. Significant heterogeneity was present for many outcomes, and sensitivity analyses suggested a relation to methodological variation in most cases. This study supports the finding that ketamine does not enhance ECT's antidepressant effect, including on early improvement, but provides substantial evidence for enhancing seizure duration and reducing electrical dose. No significant benefit was found on neurocognitive outcomes, but analysis was limited by small sample sizes and high heterogeneity. Ketamine is generally safe in ECT, particularly as a coanesthetic. Our findings provide meta-analytic support to the recommendations in ECT clinical guidelines for use of coadjuvant ketamine in ECT where seizures are suboptimal. Further studies targeting neurocognitive outcomes are encouraged.

Frequency and Duration of Course of ECT Sessions: An Appraisal of Recent Evidence

AIMS AND METHOD

This paper aims to review the recent literature regarding factors influencing the frequency and number of sessions during a course of electroconvulsive therapy (ECT) for different psychiatric disorders. We systematically reviewed English-language papers of clinical trials of ECT published since the year 2000 in terms of frequency and number of sessions of ECT.

RESULTS

None of the 30 studies meeting our inclusion criteria were specifically designed to study frequency or number of sessions of ECT. A preliminary inference may be drawn regarding the number of sessions from the information available in these papers. For depression, patients receiving brief-pulse ECT needed fewer sessions than those receiving ultra-brief ECT when these were delivered at 8-times the threshold with unilateral electrode placement or at 2.5-times the threshold with bilateral placement. For schizophrenia, those receiving bifrontal ECT and ECT at 4-times the threshold-level stimulus needed fewer sessions than those receiving bitemporal ECT and 2-times the threshold-level stimulus, respectively. There were no clinical trials of the frequency of ECT sessions.

CLINICAL IMPLICATIONS

As there is a dearth of studies specifically examining frequency and number of ECT sessions, broad recommendations from professional bodies should continue to guide practice.

Ketamine for depression clinical issues

Major depressive disorder (MDD) is a debilitating illness with significant morbidity and mortality, leading to attempted and completed suicides. It affects interpersonal relationships and also contributes to decreased productivity, causing financial burden to individuals and society. Patients often fail to respond to various antidepressant medication trials resulting in treatment-resistant depression (TRD). Current antidepressant medications work by modulating the monoaminergic systems and takes several weeks to establish a clinical response. Ketamine has been used extensively as an anesthetic agent since the 1970s, and more recent research has shown its rapid and robust effectiveness in TRD the subject of this review. Ketamine is a racemic mixture comprised of two enantiomers (R)-ketamine and (S)-ketamine and acts as an NMDA receptor antagonist. Most research studies have explored its antidepressant and antisuicidal effects by using it as an intravenous infusion or via the intranasal route due to increased bioavailability. Recently an intranasal esketamine spray was approved by the United States Food and Drug Administration (FDA) for TRD as an adjunct to standard antidepressant treatment in a supervised setting. Regarding its safety profile, multiple research studies have established the short-term safety and efficacy of ketamine in TRD. The cardiorespiratory and neuropsychiatric adverse events observed in these studies were mostly transient. However, ketamine is a scheduled agent with abuse potential, making its long-term use challenging and mandating further research.

Effects of Low-Dose Ketamine on the Antidepressant Efficacy and Suicidal Ideations in Patients Undergoing Electroconvulsive Therapy

OBJECTIVES

It remains controversial whether a subanesthetic dose of ketamine could modulate the antidepressant effect of electroconvulsive therapy (ECT) in patients with major depressive disorder. We investigated the effect of ketamine on accelerating the antidepressant efficacy of ECT.

METHODS

One hundred twenty-seven patients with major depressive disorder were included in this randomized, placebo-controlled, double-blind study. The study group received 0.3 mg/kg ketamine, and the control group received an isovolumetric dose of normal saline before undergoing ECT under propofol anesthesia. The main outcome was the Hamilton Depression Rating Scale score after each ECT session. Suicidal ideation (SI) was also evaluated using the Hamilton Depression Rating Scale. The response, remission, and recurrence rates were analyzed using time-to-event analysis.

RESULTS

No significant differences were found in the overall response, remission, and relapse rates between the groups (P > 0.05). The median number of ECT sessions for achieving response was 4.0 ± 0.41 in the study group and 7.0 ± 0.79 in the control group (P < 0.05). The median number of ECT sessions for achieving remission in the study and control groups was 8.0 ± 0.29 and 9.0 ± 0.48, respectively (P < 0.05). The median number of ECT sessions for achieving SI reduction in the study and control groups was 3.0 ± 0.75 and 6.0 ± 1.19, respectively (P < 0.05).

CONCLUSIONS

Low-dose ketamine (0.3 mg/kg) could modulate the antidepressant efficacy of ECT via accelerating the onset of its effects and reducing the number of ECT sessions required to obtain response, remission, and SI reduction, without influencing the relapse rates in remitting patients after ECT treatment.

Intermittent administration of low dose ketamine can shorten the course of electroconvulsive therapy for depression and reduce complications: A randomized controlled trial

This study aimed to investigate the efficacy and safety of intermittent low-dose ketamine on improving the efficacy of ECT. Patients diagnosed with Major Depressive Disorder (MDD) (n = 134) were randomized into 3 groups: routine ECT group (group E, n = 45); repeated ketamine-assisted ECT group (group RK, n = 43), and intermittent ketamine-assisted ECT group (group IK, n = 46). Patients in group RK were given ketamine at the dose of 0.3 mg/kg for each ECT treatment, patients in group IK were given ketamine once a week during ECT course. The depressive symptoms were assessed using the Hamilton Depression Rating Scale (HAM-D) at baseline, the end of ECT course, after 1 and 3 months, followed by an analysis of the psychiatric complications. Results indicated that ketamine-assisted ECT achieved a higher remission rate (P < 0.05), and no difference was observed between repeated and intermittent ketamine administrations. The total incidence rate of psychiatric complications in group RK (20.93%) was higher than that in group E (0%) and group IK (4.35%). In conclusion, intermittent administration of low dose ketamine in ECT significantly improved the effects of ECT and decreased psychiatric complications compared with repeated ketamine addition.

Ketamine and depression: a narrative review

Depression is the third leading cause of disability in the world. Depressive symptoms may be reduced within several weeks after the start of conventional antidepressants, but treatment resistance concerns one-third of patients who fail to achieve recovery. Over the last 20 years, ketamine, an antagonist of the N-methyl-D-aspartate receptor, has been described to have antidepressant properties. A literature review was conducted through an exhaustive electronic search. It was restricted to Cochrane reviews, meta-analyses, and randomized controlled trials (RCTs) of ketamine for major depressive disorder and/or bipolar disorder. This review included two Cochrane reviews, 14 meta-analyses and 15 trials. Ketamine was studied versus placebo, versus other comparators and as an anesthetic adjuvant before electroconvulsive therapy. In 14 publications, ketamine provided a rapid antidepressant effect with a maximum efficacy reached at 24 hrs. Its effect lasted for 1–2 weeks after infusion, but a longer-term effect is little reported. Ketamine does not seem to improve depressive symptoms at the end of electroconvulsive sessions. Safety and tolerability profiles with ketamine at low single dose are generally good in depressed patients. However, there is a lack of data concerning ketamine with repeated administration at higher doses. The clinical use of ketamine is increasing. Intranasal (S)-ketamine has recently been approved for depression by the Food and Drug Administration. It could be a promising treatment in depressed patients with suicidal ideation. Collectively, the level of proof of efficacy remains low and more RCTs are needed to explore efficacy and safety issues of ketamine in depression.

Adjunctive ketamine and electroconvulsive therapy for major depressive disorder: A meta-analysis of randomized controlled trials

BACKGROUND

Adjunctive ketamine with electroconvulsive therapy (ECT) has been investigated for treating major depressive disorder (MDD), but the findings have been inconsistent.

AIM

This is an updated meta-analysis of the efficacy and safety of ketamine augmentation of ECT in the treatment of MDD.

METHODS

Randomized controlled trials (RCTs) reporting on the efficacy and safety of ketamine and ECT were identified and analyzed.

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.

CONCLUSION

Compared to other anesthetic agents, ketamine alone does not appear to improve the efficacy of ECT. However, ketamine+other anesthetic combinations may confer a short-term advantage in improving depressive symptom at the early stages of ECT.

Ketamine in electroconvulsive therapy for depressive disorder: A systematic review and meta-analysis

Electroconvulsive therapy (ECT) is one of the most effective treatments for depressive disorder. Sub-anesthetic dose of ketamine exerts a rapid and robust antidepressive effect. However, it is still unclear whether ketamine usage in ECT is efficacious as an antidepressant. We aimed to conduct a systematic review and meta-analysis on the effects of ketamine in ECT among patients with depressive disorder. MEDLINE, EMBASE, the CENTRAL and PsycINFO for randomized controlled trials were searched to assess the effects of ketamine used in ECT until 31 Mar 2018 (PROSPERO: CRD42018081024). Sixteen studies including 928 patients were enrolled. At the end of ECT, no significant standardized mean difference (SMD) was observed in favor of the ketamine group. Depressive scores were lower in the ketamine group after 1st ECT and 3rd to 6th ECTs. The depressive scores were lower after 2nd, 3rd, 4th and 6th ECTs when the ketamine was used as an add-on anesthetic, while the depressive scores were lower after 1st ECT when ketamine alone was used. Ketamine in ECT showed no better response and remission rate, while increased adverse events, especially related to cardiovascular and psychiatric systems, during the whole ECT course. In conclusion, although ketamine used in ECT cannot reduce the depressive symptoms at the end of treatment, it could accelerate the antidepressive effect in depressive patients receiving ECT, especially in those who used ketamine as an add-on anesthetic. However, ketamine cautiously needs to be administered in ECT due to the possibility of increased risk of side effects.

Ketamine and electroconvulsive therapy: so happy together?

PURPOSE OF REVIEW

Anesthetics, such as thiopental, methohexital, propofol and ketamine have been used to induce unconsciousness for electroconvulsive therapy (ECT), each with its advantages and disadvantages. Only until recently was it discovered that ketamine may have inherent antidepressant effects. We reviewed the side effect profile of ketamine and examined the literature for whether or not ketamine augments the antidepressant effects of ECT.

RECENT FINDINGS

Systematic reviews and meta-analyses of randomized controlled trials of the potential benefits of adding ketamine to ECT treatment have generated varied conclusions. Currently there is a lack of clear evidence that ketamine with ECT is more efficacious than ECT alone.

SUMMARY

Large, multicenter randomized controlled trials are needed to further investigate the potential advantages of adding ketamine to ECT for patients with severe or refractory depression. The addition of ketamine to ECT treatment may have some early beneficial effect in patients with acute depressive disorders. Most likely, ECT itself is responsible for lasting remission from severe depression. Ketamine's side effect profile may be undesirable in certain patient populations, and so the risks and benefits of the addition of this drug to ECT treatment must be weighed.

Ketamine as the anaesthetic for electroconvulsive therapy: the KANECT randomised controlled trial - CORRIGENDUM

This notice describes a correction to the above mentioned paper.

Ketamine as anaesthesia for ECT: is there room to improve a gold standard treatment?

One meta-analysis of ketamine anaesthesia for electroconvulsive therapy found no improvement of end-point antidepressant outcomes; another meta-analysis with a broader range of included trials found that ketamine improved both early and late outcomes. If ketamine anaesthesia is useful, researchers may need to look for benefits earlier during the treatment course. Declaration of interest None.

Ketamine-based anesthesia improves electroconvulsive therapy outcomes: a randomized-controlled study

BACKGROUND

Major depressive disorder (MDD) is a common and debilitating condition that can be challenging to treat. Electroconvulsive therapy (ECT) is currently the therapeutic gold standard for treatment-resistant MDD. We tested our hypothesis that ketamine-based anesthesia for ECT results in superior improvement in treatment-resistant MDD outcomes compared with propofol-based anesthesia.

METHODS

Patients with treatment-resistant MDD were enrolled in a randomized clinical trial with assignment to ketamine- or propofol-based anesthesia arms. Using a modified intention-to-treat analysis, we compared the median number of ECT treatments required to achieve a 50% reduction (primary outcome) and a score ≤ 10 (secondary outcome) on the Montgomery-Asberg depression rating scale (MADRS) between anesthesia groups.

RESULTS

The study was terminated as significant results were found after the first planned interim analysis with 12 patients in each of the ketamine (intervention) and propofol (control) groups. All ketamine patients achieved at least a 50% MADRS reduction after a median of two ECT treatments whereas ten propofol patients (83%) achieved the same outcome after a median of four ECT treatments. All ketamine patients and seven propofol patients (58%) achieved MDD remission (MADRS ≤ 10). Log rank tests showed that both time-to-50% reduction and remission differed significantly between groups. Adverse events and recovery time were similar between groups.

CONCLUSIONS

In this early-terminated small-sized study, ketamine-based anesthesia compared with propofol-based anesthesia provided response and remission after fewer ECT sessions.

TRIAL REGISTRATION

www.clinicaltrials.gov (NCT01935115). Registered 4 September 2013.

A review of ketamine's role in ECT and non-ECT settings

Up to 20% of depressed patients demonstrate treatment resistance to one or more adequate antidepressant trials, resulting in a disproportionately high burden of illness. Ketamine is a non-barbiturate, rapid-acting general anesthetic that has been increasingly studied in treatment resistant depression (TRD), typically at sub-anesthetic doses (0.5 mg/kg over 40 min by intravenous infusion). More recent data suggest that ketamine may improve response rates to electroconvulsive therapy (ECT) when used as an adjunct, but also as a sole agent. In the ECT setting, a dose of 0.8 mg/kg or greater of ketamine demonstrates improved reduction in depressive symptoms than lower doses; however, inconsistency and significant heterogeneity among studies exists. Clinical predictors of responses to ketamine have been suggested in terms of non-ECT settings. Ketamine does increase seizure duration in ECT, which is attenuated when concomitant barbiturate anesthetics are used. However, most studies are small, with considerable heterogeneity of the sample population and variance in dosing strategies of ketamine, ECT, and concomitant medications, and lack a placebo control, which limits interpretation. Psychotomimetic and cardiovascular adverse effects are reported with ketamine. Cardiovascular adverse effects are particularly relevant when ketamine is used in an ECT setting. Adverse effects may be mitigated with concurrent propofol; however, this adds complexity and cost compared to standard anesthesia. Long-term adverse effects are still unknown, but relevant, given recent class concerns for anesthetic and sedative agents.