Please assess the completion status of the following clinical trial:

Trial Title: Nitrous Oxide Vasodilation Healthy Adult Volunteers

Study Design Characteristics:
- Allocation: None
- Intervention Model: SINGLE_GROUP
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE1
- Number of Arms: 1.0

Eligibility Criteria:
Inclusion Criteria:~* Healthy adult volunteers.~* 19 years or older (inclusive)~* English speaking.~Exclusion Criteria:~* ASA class III or greater;~* History of, or suspected, difﬁcult airway based on physical exam, facial dysmorphism or syndrome~* Any condition in which air may be trapped in a body cavity. These include, but are not limited to:~Pneumothorax or chest injury, concurrent acute asthma exacerbation, middle ear occlusion, intestinal obstruction, ileus, or abdominal distension, sinusitis or maxillofacial injuries with potential for trapped gas, recent intraocular surgery or penetrating globe injury, air embolus, severe bullous emphysema (consider in patients with cystic ﬁbrosis), history of craniotomy in previous three weeks~* Pregnancy (1st and 2nd trimester)~* Increased intracranial pressure, impaired level of consciousness, or head injury~* Known Vitamin B12 deﬁciency~* Known MTHFR Deﬁciency (Inborn error of metabolism)~* History of bleomycin administration (note that the oxygen component of N2O administration is what interacts with bleomycin to cause pulmonary toxicity)~* Intoxication with alcohol or other drugs~* Any condition in which patient may be catecholamine-depleted (e.g. septic shock)~* Recent history of altered mental status~* Pulmonary hypertension~* Congestive heart failure.~* Trainees, including students, residents, and fellows, working in the pediatric emergency department.

- Gender: ALL
- Minimum Age: 19 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- 50% Nitrous oxide (Type: EXPERIMENTAL): None

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