Nitrous Oxide- Suicidal Ideation
Major Depressive Disorder, Depression, Mood Disorders
About this trial
This is an interventional treatment trial for Major Depressive Disorder focused on measuring Nitrous Oxide, Anesthetics
Eligibility Criteria
Inclusion Criteria:
- Patients aged 18-65 years old;
- current diagnosis of unipolar, major depressive disorder (MDD) without psychosis as defined by the Mini-International Neuropsychiatric Interview (MINI) and The Fourth Edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) DSM-IV determined by clinical interview and by a baseline score of ≥18 on the HDRS-21 (Hamilton Depression Rating Scale 21-item;
- moderate to severe SI defined as a score ≥3 on the HDRS-21 suicide item (item #3);
- will have good command of the English language;
- will have been voluntarily admitted to the inpatient Psychiatric Units at Barnes-Jewish Hospital/Washington University in St. Louis, MO.
Exclusion Criteria:
- Lifetime DSM-IV (obtained via MINI) diagnoses of schizophrenia, schizoaffective disorders, bipolar disorder, obsessive-compulsive disorder, evidence of severe personality disorder (e.g., history of recurrent self-mutilation/cutting, significant and recurrent tumultuous relationships), and panic disorders;
- past 12-month substance abuse/dependence other than nicotine;
- active psychotic symptoms;
- significant pulmonary disease and/or requiring supplemental oxygen;
- administration of other N-Methyl-D-aspartate (NMDA)-receptor antagonist treatment (e.g., ketamine) within two weeks of entry into study;
- currently receiving electroconvulsive therapy;
- contraindications for nitrous oxide (pneumothorax, bowel obstruction, middle ear occlusion, elevated intracranial pressure, chronic cobalamin and/or folate deficiency treated with folic acid or vitamin B12);
- past 12-month history of head trauma;
- women who are pregnant or breastfeeding;
- any other factor that in the investigators' judgment may affect patient safety or compliance.
Sites / Locations
- Washington University School of Medicine
Arms of the Study
Arm 1
Arm 2
Experimental
Placebo Comparator
Nitrous Oxide
Placebo Gas
Nitrous oxide, an odorless, colorless gas typically used as an induction agent for general anesthesia or for dental sedation, is a known N-methyl-D-aspartate (NMDA) antagonist. It will be given at 50% nitrous oxide/50% oxygen in this study. Participants will undergo a maximum of four one hour inhalation sessions as inpatients and 2 booster sessions as outpatients during which they will receive inhaled nitrous oxide.
Placebo gas given at 50% nitrogen [inert]/50% oxygen. Participants will undergo a maximum of four one hour inhalation sessions as inpatients and 2 booster sessions as outpatients during which they will receive placebo gas.