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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
A randomised controlled trial of “light” versus “deep” sedation for elective outpatient colonoscopy: recall, procedural conditions and recovery
Scientific title
In patients booked for elective, outpatient colonoscopy under sedation are those who are lightly sedated, compared to those deeply sedated, equally likely to have recall of the procedure.
Secondary ID [1] 259846 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Sedation for colonoscopy 265419 0
Condition category
Condition code
Anaesthesiology 265579 265579 0 0
Oral and Gastrointestinal 265597 265597 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Study type
Description of intervention(s) / exposure
Sedation will be with an intravenous infusion of propofol (a IV anaesthetic agent) using TCI effect site steered dosing with a start point of 1.5mcg/ml. This will be titrated by the anaesthetist to achieve the target BIS with no maximum dose. A bolus dose of fentanyl (an opioid) of 0.7mcg/kg to a maximum of 100mcg will be given for those under 70 years, and for those over 70 years this will be 0.5mcg/kg to a maximum of 75mcg. The sedation will continue for the duration of the colonoscopy (usual duration 20-30 mins).

The bispectral index (BIS) is a modified EEG signal which is a validated measure for the depth of anaesthesia which generates a number from 0 (no cortical activity) to 100 (awake). Measurement is made by the placement of a measurement strip on the patient's forehead.

In this study the intervention is "light sedation" in which the BIS target will be 70-80. The propofol infusion will be increased or decreased to remain in this range.
Intervention code [1] 264265 0
Treatment: Other
Comparator / control treatment
The same sedation regime will be used in the "deep sedation" group but the BIS target will be less than 60. The same medications in the same doses will be used in the deep sedation group but titrated to a different endpoint. The eventual propofol effect site target required would be expected to be higher in the deep sedation group. Again, there is no maximum dose specified.
Control group

Primary outcome [1] 262379 0
Patient reported rate of recall of procedure.

This will be determined in the recovery room by administration of the modified Brice questionnaire to all patients.
Timepoint [1] 262379 0
On day of procedure
Secondary outcome [1] 273654 0
Rate of cardio-respiratory complications managed by the treating anaesthetist. This is assessed by the completion of a checklist, by the anaesthetist, where the exact parameters defining a complication are specified for the following categories:

Airway obstruction
Timepoint [1] 273654 0
Day of procedure
Secondary outcome [2] 273655 0
Ease of procedural completion recorded on 1-10 scale
Timepoint [2] 273655 0
Day of procedure
Secondary outcome [3] 273656 0
Patient satisfaction with care. Patients will be asked to rate their satisfaction with the sedation they received on a 5 point scale from very satisfied to very dissatisfied.
Timepoint [3] 273656 0
Day of procedure when ready for hospital discharge
Secondary outcome [4] 273657 0
cognitive function at hospital discharge as measured by CogState test battery
Timepoint [4] 273657 0
Day of procedure when ready for hospital discharge

Key inclusion criteria
Booked for elective outpatient colonoscopy under sedation
ASA physical status grade 1-3
Adequate english language comprehension to complete study procedures
Cognitive function sufficient to provide own consent for the procedure
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Booked for combined colonoscopy and gastroscopy
emergency inpatient procedures
significant cardio-respiratory dysfunction (ASA4-5)

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Patients booked for elective outpatient colonoscopy will be approached in preadmission clinic or on the day of surgery, given trial information, and asked for consent to participate.

Basic demographic information will be collected and the medical record reviewed to confirm eligibility.

In consenting, eligible participants randomisation to light or deep sedation will occur prior to commencement of clinical care. This will be by the treating anaesthetist opening an opaque envelope labelled with a unique study number. The anaesthetist's cannot be blinded to group allocation as they have to administer the appropriate sedation.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Computer generated randomisation schedule
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment postcode(s) [1] 7181 0
3050 - Royal Melbourne Hospital

Funding & Sponsors
Funding source category [1] 287644 0
Name [1] 287644 0
ANZCA Project Grant
Address [1] 287644 0
630 St Kilda Road
Melbourne Vic 3004
Country [1] 287644 0
Primary sponsor type
Megan Allen
Department of Anaesthesia and Pain Management
The Royal Melbourne Hospital
Parkville, Victoria, 3050
Secondary sponsor category [1] 263846 0
Name [1] 263846 0
Address [1] 263846 0
Country [1] 263846 0
Other collaborator category [1] 251894 0
Name [1] 251894 0
Prof Kate Leslie
Address [1] 251894 0
Department of Anaesthesia and Pain Management
The Royal Melbourne Hospital
Parkeville, VIC, 3050
Country [1] 251894 0

Ethics approval
Ethics application status
Ethics committee name [1] 266708 0
Melbourne Health HREC
Ethics committee address [1] 266708 0
Office for Research
The Royal Melbourne Hospital
Parkville, VIC, 3050
Ethics committee country [1] 266708 0
Date submitted for ethics approval [1] 266708 0
Approval date [1] 266708 0
Ethics approval number [1] 266708 0

Brief summary
In this trial, patients undergoing elective colonoscopy under sedation will be randomised to BIS-guided sedation targeting either “light” or “deep” sedation. Sedation will be achieved with a standardised regimen of target-controlled infusion of propofol and fentanyl bolus. The primary end point will be the incidence of procedure recall in each group. The procedural conditions, cardio-respiratory complications and recovery including cognitive function will be assessed. The patient satisfaction with anaesthesia care will be recorded.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 32376 0
Dr Megan Allen
Address 32376 0
Department of Anaesthesia and Pain Management The Royal Melbourne Hospital Parkville, VIC, 3050
Country 32376 0
Phone 32376 0
+61 3 9342 7000
Fax 32376 0
Email 32376 0
Contact person for public queries
Name 15623 0
Dr Dr Megan Allen
Address 15623 0
Department of Anaesthesia and Pain Management
The Royal Melbourne Hospital
Parkville, VIC, 3050
Country 15623 0
Phone 15623 0
Fax 15623 0
Email 15623 0
Contact person for scientific queries
Name 6551 0
Dr Dr Megan Allen
Address 6551 0
Department of Anaesthesia and Pain Management
The Royal Melbourne Hospital
Parkville, VIC, 3050
Country 6551 0
Phone 6551 0
Fax 6551 0
Email 6551 0

No information has been provided regarding IPD availability
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary