The editorial by Dr Nemeroff supports our clinic design of having a psychiatrist evaluate patients to confirm diagnosis of treatment resistant depression and having anesthesiologists administer the ketamine infusion
While benefits of decreased suicidal ideation are seen with IV administration of ketamine (versus midazolam) the exact mechanism of action is obscure and outrageous claims should not be made at this point
Results of this study show ketamine acts on the mu, kappa, and delta opioid receptors as an agonist (we already know ketamine acts on the NMDA receptor as an antagonist). The study conclusion shows that activation of the opioid receptors by ketamine is necessary for its antidepressant effects.
The study proved the above findings by administering study patienst naltrexone (an opioid receptor antagonist) prior to the administration of IV ketamine therapy. Those subjects that received naltrexone prior to receiving the IV ketamine infusion therapy showed decreased effects of the ketamine on depressive symptoms.
In summary, NMDA receptors are unregulated in chronic pain states, especially in the dorsal horn of the spinal cord, leading to central sensitization
NMDA antagonism may help decrease spontaneous pain, hyperalgesia, and allodynia (ketamine is an NMDA antagonist and has proven benefit)
Ketamine has a role to decrease the development of chronic pain states in the perioperative period.
Perioperative use of ketamine is on the rise because of its benefits with pain management and the goals of seeking opioid free pain therapies
ASRA (Anesthesia Society on Regional Anesthesia) has consensus guidelines for the infusion of subanesthetic doses of ketamine for pain conditions
The guidelines also outline indication, contraindications, and promote adequate monitoring and administration by trained professionals only.
Electroconvulsive therapy (ECT) is a procedure used to treat patients with major depression, treatment resistant depression, and depression with suicidal ideation
The procedure delivers an electrical stimulus to the brain initiating a seizure which is what brings about beneficial changes for the patient. This procedure is done under anesthesia
The brief hemodynamics changes that occur while administering this therapy can cause cardiac morbidity and mortality.
This systematic review found that in every 1/200-1/500 ECT procedures there were cases of cardiac morbidity (1/50 ECT patients)
Clinical studies consistently demonstrate that a single subanesthetic dose of ketamine (NMDA receptor antagonist) produces fast acting antidepressant response if the patient is suffering a major depressive episode, although the mechanism remains unclear
The effects of the ketamine are seen within 2 hours of the infusion
The benefits are seen immediately which is in contrast to tradition oral antidepressant therapy which can take weeks for effect
The benefit of ketamine is particularly good in cases of major depression with suicidal ideation
Elucidating the exact mechanism of ketamine’s action requires further studying
This is a case report showing dramatic improvement of symptoms and reversal of suicidal ideation in a combat veteran with major depressive disorder and PTSD (post traumatic stress disorder)
The article summarizes a randomized, double blind crossover study at the Mount Sinai Medical center showing proven benefits of IV ketamine administration in patients suffering from PTSD vs placebo.
