Multidisciplinary development of guidelines for ketamine treatment for treatment-resistant major depression disorder for use by adult specialist mental health services in New Zealand

BACKGROUND

The evidence base for racemic ketamine treatment for treatment-resistant major depressive disorder (TRD) continues to expand, but there are major challenges translating this evidence base into routine clinical care.

AIM

To prepare guidelines for ketamine treatment of TRD that are suitable for routine use by publicly funded specialist mental health services.

METHOD

We consulted with senior leadership, clinical pharmacy, psychiatrists, nursing, service users and Māori mental health workers on issues relating to ketamine treatment. We prepared treatment guidelines taking the evidence base for ketamine treatment and the consultation into account.

RESULTS

Ketamine treatment guidance is reported. This offers two treatment pathways, including a test of ketamine responsiveness with intramuscular ketamine and the dominant use of oral ketamine for a 3-month course to maximise the opportunity for the short-term benefits of ketamine to accumulate.

CONCLUSIONS

We have responded to the challenges of translating the evidence base for ketamine treatment into a form suitable for routine care.

Oral ketamine for depression: An updated systematic review

Objectives: Ketamine is a glutamate N-methyl-D-aspartate receptor antagonist that can be used to treat major depressive disorder by single or repeated infusions. However, the accessibility and scalability of oral ketamine make it preferred over intravenous ketamine. In this systematic review, we aim to evaluate the efficacy, tolerability, and safety of oral ketamine, esketamine and r-ketamine for unipolar and bipolar depression. Materials and methods: Electronic databases were searched from inception to September 2022 to identify relevant articles. Results: Twenty-two studies, including four randomized clinical trials (RCTs), one case series, six case reports, five open-label trials and six retrospective chart review studies involving 2336 patients with depression were included. All included studies reported significant improvement following ketamine administration. Ketamine was well tolerated without serious adverse events. However, RCTs had a high risk of bias due to analysis methods and adverse events monitoring. Ketamine dosage varied from 0.5 to 1.25 mg/kg. The frequency of administration was daily to monthly. Several important limitations were identified, most notably the small number of RCTs. Conclusions: Taken together, preliminary evidence suggests the potential for antidepressant effect of oral ketamine. However, further research with large sample size and long follow-up period is needed to better determine the antisuicidal effect and efficacy in treatment-resistant depression.

An Update on the Efficacy and Tolerability of Oral Ketamine for Major Depression: A Systematic Review and Meta-Analysis

BACKGROUND

Intravenous Ketamine has shown robust antidepressant efficacy although other routes of administration are currently needed. We conducted a systematic review and meta-analysis of studies evaluating the efficacy and tolerability of oral ketamine for depression.

METHODS

A comprehensive search of major electronic databases from inception to April 2020 was performed. Studies of oral ketamine for depression, from case series to randomized clinical trials, were eligible. Randomized controlled trials were included in a meta-analysis, focusing on response, remission, time to effect, and side effects.

RESULTS

A total of 917 articles were identified with 890 studies screened, yielding a total of 10 studies included in our systematic review.Three randomized controlled trials (RCTs) (N = 161, mean age 37.9 ± 9.5 years, 58.6% females) were included in the meta-analysis. Pooled analysis suggested a significant antidepressant effect of oral ketamine (SMD: -0.75; 95% CI: -1.08, -0.43; p<0.0001; I² = 0%) although remission rates (RR:2.77; 95% CI:0.96, 8.00; p = 0.06) and response rates (RR:2.58; 95% CI:0.94,7.08; p = 0.07) were marginal compared to placebo at the endpoint. Oral ketamine antidepressant effects seemed to take effect at the 2nd week (SMD: -0.71; 95% CI: -1.08, -0.35; p = 0.001; I² = 0%). There were no significant differences in the overall side-effects between oral ketamine and the placebo group (RR 1.28, 95% CI: 0.89-1.83; p = 0.19).

CONCLUSION

This focused meta-analysis of oral ketamine suggests a marginal efficacy for major depressive disorder without increased risk of adverse events. Further larger sample studies are needed to confirm these preliminary findings, analyzing differential response/remission rates by affective disorder, optimal dosing strategies, and its long-term effects.

Anesthesia for tracheostomy for huge maxillofacial tumor

Providing sedation for patients with compromised upper airway is challenging. A 19-year-old female patient with huge maxillofacial tumor invading the whole pharynx scheduled for elective tracheostomy under local anesthesia due to compromised airway. The patient had gastrostomy tube for feeding. Venous cannulation was totally refused by the patient after repeated trials for exhausted sclerosed veins. Pre-operative mixture of dexmedetomidine with ketamine was administered through the gastrostomy tube with eutectic mixture of local anesthetics cream application over the planned tracheostomy site. The patient was sedated with eye opening to command. Local infiltration followed by tracheostomy was performed without patient complaints or recall of operative events.

Withdrawal assessment following subchronic oral ketamine administration in Cynomolgus macaques

Recently there is increased regulatory interest in the assessment of physical dependence and withdrawal as part of the safety assessment for novel therapeutic entities. Choosing appropriate and sensitive parameters to detect withdrawal syndromes, and relevant positive control comparator drugs that can be administered in the same manner as the test agent, are critical study design elements. Pilot studies to determine the effects of oral ketamine in cynomolgus monkeys during, and following cessation of treatment, were explored. Detailed behavioral observations (both remote and interactive), food consumption, and body weight and temperature, were assessed during the dose-ranging, repeat dose (5 or 14 days), and withdrawal phases (3 or 5 days). Doses explored during dose-ranging included 20, 40, 100, or 200 mg/kg ketamine; subsequent withdrawal assessments were conducted following repeat dosing of 150 mg/kg. In the 14-day dosing study, exposure to ketamine and norketamine was assessed following 8 days of dosing. Administration of 150 mg/kg ketamine produced decreased activity, loss of balance, ataxia, hunched posture, nystagmus, lateral recumbence, and changes in alertness levels during dosing phases. When ketamine was withdrawn, increased reactivity, increased activity, and stereotypic behaviors were demonstrated that were absent during baseline or the dosing phase of the studies.