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Trial details imported from

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Registration number
Ethics application status
Date submitted
Date registered
Date last updated

Titles & IDs
Public title
"Light" Versus "Deep" Bispectral Index (BIS) Guided Sedation for Colonoscopy
Scientific title
A Randomised Controlled Trial of "Light" Versus "Deep" Sedation for Elective Outpatient Colonoscopy: Recall, Procedural Conditions and Recovery
Secondary ID [1] 0 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Anaesthesia 0 0
Condition category
Condition code

Study type
Description of intervention(s) / exposure
Other interventions - Sedation depth

Experimental: "light" sedation - In this study the depth of sedation will be guided by the Bispectral Index monitor (BIS monitor). A BIS value of 70-80 will be targeted in the "light" sedation arm.

Active Comparator: "deep" sedation - In this study the "deep" sedation arm will have a BIS value of less than 60 targeted.

Other interventions: Sedation depth
The intervention is the depth of sedation targeted in this study.
Patients enrolled in this study will be sedated with the same medications (fentanyl bolus and propofol target controlled infusion), and at the same starting doses, in each study arm. However, the depth of sedation targeted will differ between the arms, and this depth will be guided by the BIS monitor.
It is expected that those patients randomised to "deep" sedation will require a higher dose of sedative medication to achieve their target BIS value (<60) than those in the "light" sedation group (BIS 70-80).

Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Primary outcome [1] 0 0
Recall of procedure - Upon rousing patients will be asked if they remember anything between the commencement of sedation and when they awoke from sedation
Timepoint [1] 0 0
1 day. Day of procedure
Secondary outcome [1] 0 0
Complications - The treating anaesthetist will record if any of the following complications occur during the sedation for colonoscopy.
Airway obstruction
Timepoint [1] 0 0
1 day. Day of procedure only.
Secondary outcome [2] 0 0
Speed and quality of recovery - Time from starting sedation until opening eyes in the post anaesthesia care unit, and time until readiness for hospital discharge will be recorded.
Cognitive function at hospital discharge, compared to pre-procedure function, will be assessed by the CogState(TM) test battery.
Timepoint [2] 0 0
1 day. Day of procedure only. Measured before discharge from hospital
Secondary outcome [3] 0 0
Satisfaction - Proceduralist and anaesthetist satisfaction with the sedation will be recorded at the end of the procedure.
Patient satisfaction with their anaesthesia care will be assessed at the time they are ready for hospital discharge.
Timepoint [3] 0 0
1 day. Day of procedure only. Measured before discharge from hospital
Secondary outcome [4] 0 0
Dreaming - Upon rousing in the post anaesthesia care unit patients will be asked the modified Brice questionnaire ("What is the last thing you remember before you went to sleep?", "What is the first thing you remember when you woke up?", "Did you remember anything in between?", and "Did you have any dreams?").
Dreaming will be assessed by the response to quesion 4.
Timepoint [4] 0 0
1 day. Day of procedure.

Key inclusion criteria
- Plan for elective outpatient colonoscopy under sedation

- Able and willing to provide written informed consent for study entry and completion of
all study related procedures

- American Society of Anesthesiologists' (ASA) physical status grade 1-3
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
- Colonoscopy and gastroscopy booked as joint procedures

- Colonoscopy on emergency patients and/or inpatients

- Inadequate English comprehension (verbal and written to understand the Participant
Information and Consent Form)

- Intellectual or psychiatric disability that prevents consent to and comprehension of
study procedures

- Significant cognitive impairment that prevents independent conduct of activities of
daily living or results in 3rd party procedural consent being obtained

- ASA physical status grade 4-5

Study design
Purpose of the study
Supportive Care
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
The people analysing the results/data
Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Data analysis
Reason for early stopping/withdrawal
Other reasons
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 hospital [1] 0 0
Royal Melbourne Hospital - Parkville
Recruitment postcode(s) [1] 0 0
3050 - Parkville

Funding & Sponsors
Primary sponsor type
Melbourne Health

Ethics approval
Ethics application status

Brief summary
In this trial, patients undergoing elective colonoscopy under sedation will be randomised to
BIS-guided sedation targeting either "light" (bispectral index [BIS] 70-80) or "deep"
(BIS<60) 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 - this will be assessed at the conclusion of the procedure.
The procedural conditions, cardio-respiratory complications and recovery including cognitive
function will be assessed during and immediately after the procedure. The incidence of
dreaming and patient satisfaction with anaesthesia care will be recorded immediately after
the procedure. The study will be complete when the patient leaves the hospital on the day of
the procedure.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 0 0
Megan L Allen, BMBS
Address 0 0
Melbourne Health
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Address 0 0
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for scientific queries

Summary results
Other publications