Please assess the completion status of the following clinical trial:

Trial Title: A Single-centre Study of Entonox Versus Midazolam Sedation in Gastroscopy

Study Design Characteristics:
- Allocation: RANDOMIZED
- Intervention Model: PARALLEL
- Observational Model: None
- Primary Purpose: TREATMENT
- Time Perspective: None
- Masking: NONE
- Phase: PHASE4
- Number of Arms: 2.0

Eligibility Criteria:
Inclusion Criteria:~* Male/female aged 18 years or over~* Confirmed clinical requirement to undergo diagnostic gastroscopy~* Suitable for sedation~* Able to provide informed consent~Exclusion Criteria:~* History of chronic respiratory or significant cardiac disease~* Requirement for longer procedure eg Barrett's surveillance~* Previous known adverse reaction to Entonox~* Entonox use in previous 4 days~* Known current vitamin B12 or folate deficiency~* Unable to provide consent~* Any known contraindication to Entonox:~* Gas trapped in a part of the body where its expansion may be dangerous, such as air lodged in an artery or artificial traumatic or spontaneous pneumothorax (collapsed lung).~* Decompression sickness (the bends) or following a recent dive~* Air encephalography~* Severe bullous emphysema~* Myringoplasty~* Gross abdominal distension~* Recent severe injuries to the face and jaw~* Current or recent head injuries~* If the patient has recently had any eye surgery where injections of gas have been used

- Gender: ALL
- Minimum Age: 18 Years
- Maximum Age: None
- Healthy Volunteers: f

Study Arms:
- Midazolam (Type: ACTIVE_COMPARATOR): midazolam sedation combined with pharyngeal anaesthesia~Participants randomized to receive midazolam will have an intravenous cannula sited and, following the administration of xylocaine throat spray as above, will be put into the left lateral position. They will then be given up to 5mg midazolam as appropriate to achieve conscious sedation as for standard protocol in endoscopy.
- Entonox (Type: EXPERIMENTAL): Entonox combined with pharyngeal anaesthesia.~Pharyngeal anaesthesia, given as 8-16 sprays of xylocaine to the pharynx; 3 minutes will be given to allow the pharynx to become anaesthetized.~Participants randomized to receive Entonox will be given the 50:50 nitrous oxide:oxygen mix via a mouthpiece with a demand valve system, once in position for the procedure. Inhalations will be given for 3-5 minutes (or until the participant feels adequately sedated) measured using a stopwatch. Oxygen will be given at 2 litres per minute via nasal cannulae during the procedure, (standard care for sedated procedures). The endoscopist will then proceed to intubate the cricopharynx and perform the procedure in the standard manner.

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