Please assess the completion status of the following clinical trial:

Trial Title: Network-Level Effects of Nitrous Oxide in the Human Brain

Study Design Characteristics:
- Allocation: None
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: BASIC_SCIENCE
- Time Perspective: None
- Masking: NONE
- Phase: PHASE4
- Number of Arms: 1.0

Eligibility Criteria:
Inclusion Criteria:~1. Body mass index \<30~2. Must be right-handed~3. Must be capable of giving written informed consent~Exclusion Criteria:~1. History of obstructive sleep apnea;~2. History of a difficult airway with a previous anesthetic~3. Gastroesophageal reflux;~4. Hypertension or other cardiovascular abnormalities;~5. Pulmonary hypertension;~6. History of recreational drug use;~7. History of chronic alcohol abuse~8. Having any chronic medical illness involving pain;~9. History of major depression;~10. History of psychosis or bipolar disorder;~11. History of methylenetetrahydrofolate reductase deficiency;~12. History of a known hypersensitivity to ketamine, midazolam, Zofran, labetalol or glycopyrrolate~13. History of seizures or other neurologic disorders;~14. Pregnant or nursing mothers;~15. Tattoos on the head or neck region - all other tattoos are subject to determination by investigators;~16. Contraindications to neuroimaging methods;~17. Any impairment, activity or situation that in the judgment of the Study Coordinator or Principal Investigators would prevent satisfactory completion of the study protocol.

- Gender: ALL
- Minimum Age: 21 Years
- Maximum Age: 40 Years
- Healthy Volunteers: t

Study Arms:
- Nitrous Oxide - inhaled (Type: EXPERIMENTAL): Each volunteer will participate in one scanning visit in which simultaneous functional magnetic resonance imaging (fMRI) and electroencephalogram (EEG) data will be collected wherein they receive placebo (20 minutes) followed by inhaled nitrous oxide at subanalgesic levels (35% inhaled concentration) over 40 minutes.

Based on this trial design, predict the completion outcome and termination type (if applicable).