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

Phase 4

Terminated

Conditions: Patients Requiring Diagnostic Gastroscopy With Sedation

Interventions: Drug: Entonox
Drug: Midazolam

Registration Number: NCT01744184

Lead Sponsor: The Royal Bournemouth Hospital

Brief Summary: This study aims to determine whether Entonox (gas and air) is at least as good as intravenous midazolam in providing analgesia and sedation during gastroscopy. Entonox is used as an adjunct in lower gastrointestinal procedures but is not routinely used in gastroscopy, and there is only one similar published study to date, which was performed in children. The main advantage of Entonox over midazolam is the quick recovery time following withdrawal of the agent, which enables patients to return to independent normal life. The investigators would like to be able to offer Entonox to patients as an option for sedation during gastroscopy, this study is being conducted to determine if it is a safe and feasible option.

Detailed Description: Not available

Recruitment & Eligibility

Status: TERMINATED

Sex: All

Target Recruitment: 62

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

Study & Design

Study Type: INTERVENTIONAL

Study Design: PARALLEL

Arm && Interventions

Group	Intervention	Description
Entonox	Entonox	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.
Midazolam	Midazolam	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.

Primary Outcome Measures

Name	Time	Method
Percentage of Patients Mild or no Discomfort During Gastroscopy	During gastroscopy procedure	Percentage of patients with a score of 4 or 5 on the 5-point modified global rating scale comfort score, as measured by the patient, will be compared between the midazolam and entonox groups, per protocol. The comfort score ranges from 1-5 with 1 meaning patient was in extreme discomfort frequently during procedure and 5 being no discomfort, resting comfortably throughout. The score is completed by the patient while they are in the recovery area post procedure and prior to discharge from the unit.

Secondary Outcome Measures

Name	Time	Method
Number of Participants With Completed Procedures in Both Arms of the Study.	Day of procedure	The percentage of participants with completed procedures in both arms of the study confirmed by data collection.
Comparison of Procedure Time	Defined as start time to end time of gastroscopy.	Comparison of procedure time, defined as start time to end time in the per protocol population, between the two groups.
Comparison of Procedure Start Time to Discharge.	Procedure to discharge	Comparison of gastroscopy procedure start time to discharge from endoscopy department post-procedure care time in the per protocol population between the two groups.
Number of Patients With Adverse Events.	Consent to 72 hours post discharge from the endoscopy unit which is the same day as the procedure.	Number of patients reporting adverse events.
Comparison of Visual Analogue Scale Scores.	Completed after procedure completion during the post-procedure care and prior to discharge from the endoscopy unit.	Comparison of VAS (Visual Analogue Scale) scores between the two groups (per protocol). The scale ranges between 0 and 100 where 0 is the worst imaginable experience and 100 being very comfortable. The visual measure is a 100mm line and the score is measured by the participant marking on the line how they felt the procedure was. The research team then measure the line and confirm the score to the nearest mm to get a score of 0-100.
5-point Modified Global Rating Scale Comfort Nurse Score	Completed after procedure completion during the post-procedure care and prior to discharge from the endoscopy unit.	Percentage of patients with a score of 4 or 5 on the 5-point comfort scale, as measured by the endoscopy nurse, will be compared between the midazolam and Entonox groups, per protocol. The comfort score ranges from 1-5 with 1 meaning patient was in extreme discomfort frequently during procedure and 5 being no discomfort, resting comfortably throughout. This score is completed by the endoscopy nurse immediately following the patients procedure.