ColonoscopyNCT07885059
Dose-sparing Balanced Propofol Sedation in Colonoscopy
A study testing Standard-dose balanced propofol analgosedation and Dose-sparing balanced propofol analgosedation in people with Colonoscopy and Sedation and Analgesia, run by University of Split, School of Medicine at 2 sites in Croatia.
Trial summary
This randomized controlled trial compared two balanced propofol analgosedation strategies in adults undergoing elective colonoscopy. Participants were randomized to either a standard-dose protocol using an initial propofol dose of 1.0 mg/kg or a structured dose-sparing protocol using an initial propofol dose of 0.5… Read more about this study
- Who is it for?
- Ages 18 to 65 years
- Conditions the study is for
- Colonoscopy, Sedation and Analgesia
- What is being tested?
- Standard-dose balanced propofol analgosedation and Dose-sparing balanced propofol analgosedation
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 76 participants
- Where
- 2 sitesCroatia
- Study dates
- 5 Jun 2022to 8 Feb 2024
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 to 65 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Age 18-65 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective diagnostic colonoscopy
- Ability to provide written informed consent
Who cannot join
- ASA physical status IV or higher
- Mallampati class III or higher
- Known allergy or contraindication to any of the study medications, including propofol, midazolam, or fentanyl
- Known allergy or contraindication to soy or egg products
- Known sleep apnea
- History of seizures
Show all 11Show fewer
- Previous colonic surgery
- Planned therapeutic colonoscopy or planned endoscopic intervention
- Pregnancy or lactation
- Psychiatric disorder or long-term use of psychotropic medication
- Inability to complete the study questionnaires
Trial locations and contacts
2 sites in 1 country.
Croatia2 sites
Polyclinic J&J Medici
Split, Split-Dalmatia County, 21000
University Hospital of Split
Split, Split-Dalmatia County, 21000
About this study
Official title: Dose-sparing Balanced Propofol Analgosedation for Colonoscopy: a Randomized Controlled Trial of a Structured Sedation Protocol
This randomized controlled trial compared two balanced propofol analgosedation strategies in adults undergoing elective colonoscopy. Participants were randomized to either a standard-dose protocol using an initial propofol dose of 1.0 mg/kg or a structured dose-sparing protocol using an initial propofol dose of 0.5 mg/kg. Both protocols included midazolam and fentanyl. The standard-dose protocol was anesthesiologist-guided, whereas the dose-sparing protocol was administered by a gastroenterologist trained in advanced life support and airway management, with an anesthesia technician present and an anesthesiologist immediately available if required. The primary outcomes were patient satisfaction and clinically relevant respiratory adverse events, with apnea lasting more than 30 seconds as the principal respiratory safety endpoint. Secondary outcomes included propofol exposure, recovery, procedural performance, cardiovascular adverse events, depth of sedation and nociception-related indices, and endoscopist satisfaction.
Read the detailed description
This randomized controlled trial evaluated two protocol-based strategies for balanced propofol analgosedation in adults undergoing elective colonoscopy. Eligible participants were 18-65 years of age with American Society of Anesthesiologists (ASA) physical status I-III. Participants were randomized in an intended 1:1 ratio to either a standard-dose balanced propofol protocol or a structured dose-sparing protocol.
Both groups received intravenous midazolam, fentanyl, and propofol. Midazolam was administered at 0.05 mg/kg, up to a maximum dose of 5 mg, followed by fentanyl 0.001 mg/kg. The initial propofol dose was 1.0 mg/kg in the standard-dose group and 0.5 mg/kg in the dose-sparing group. Additional propofol boluses were administered according to clinical need and patient response during the procedure.
In the standard-dose group, sedation was guided by an anaesthesiologist. In the dose-sparing group, sedation was guided by a gastroenterologist trained in advanced life support and airway management, with an anaesthesia technician present and an anaesthesiologist immediately available if required. Because the sedation provider and propofol dosing strategy differed together between study groups, the trial was designed to compare the complete protocol-based care strategies rather than to determine the independent effect of provider specialty.
Participants underwent continuous cardiorespiratory monitoring, including pulse oximetry, heart rate, non-invasive blood pressure, and capnography with end-tidal carbon dioxide monitoring. Sedation depth was additionally assessed using clinical sedation scoring and processed electroencephalographic indices.
The primary outcomes were patient satisfaction and clinically relevant respiratory adverse events. Clinically relevant apnea, defined as an apnea episode lasting more than 30 seconds, was analyzed as the principal respiratory safety endpoint. Secondary outcomes included total propofol exposure, additional propofol requirements, early and total recovery time, procedural performance, cardiovascular adverse events, depth of sedation and nociception-related indices, endoscopist satisfaction, and patient-reported anxiety and pain. Recovery was assessed using standard post-anaesthesia recovery criteria.
The study was designed to determine whether a structured dose-sparing balanced propofol strategy could reduce sedative drug exposure and respiratory adverse events while maintaining adequate procedural conditions, recovery, and patient and endoscopist satisfaction.
- Conditions
- Colonoscopy, Sedation and Analgesia
- Being tested
- Standard-dose balanced propofol analgosedation, Dose-sparing balanced propofol analgosedation
- Keywords
- Colonoscopy, Gastroenterologist-guided sedation, Anaesthesiologist-guided sedation, Propofol, Midazolam, Fentanyl, Balanced Propofol sedation, Analgosedation
- Medical subject headings
- Agnosia
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Standard-dose balanced propofol analgosedationDrug
Also called Standard-dose balanced propofol sedation, Anaesthesiologist-guided balanced propofol analgosedation
Intravenous balanced analgosedation with midazolam, fentanyl, and propofol. Midazolam was administered at 0.05 mg/kg, up to a maximum dose of 5 mg. Fentanyl 0.001 mg/kg was administered 3 minutes later, followed by an initial propofol bolus of 1.0 mg/kg at minute 5. Additional propofol boluses of 10-30 mg were administered according to clinical need and patient response during colonoscopy. Sedation and monitoring were guided by an anaesthesiologist with an anaesthesia technician present.
Dose-sparing balanced propofol analgosedationDrug
Also called Dose-sparing balanced propofol sedation, Gastroenterologist-guided balanced propofol analgosedation
Intravenous balanced analgosedation with midazolam, fentanyl, and propofol. Midazolam was administered at 0.05 mg/kg, up to a maximum dose of 5 mg. Fentanyl 0.001 mg/kg was administered 3 minutes later, followed by an initial propofol bolus of 0.5 mg/kg at minute 5. Additional propofol boluses of 10-30 mg were administered according to clinical need and patient response during colonoscopy. Sedation and monitoring were guided by a gastroenterologist trained in advanced life support and airway management, with an anaesthesia technician present and an anaesthesiologist immediately available if required.
| Study group | Role | What they receive |
|---|---|---|
| Standard-dose balanced propofol analgosedation | Active comparator | Intravenous midazolam 0.05 mg/kg (maximum 5 mg), followed by fentanyl 0.001 mg/kg and an initial propofol bolus of 1.0 mg/kg. Additional propofol boluses of 10-30 mg were administered according to clinical need. Sedation and monitoring were guided by an anesthesiologist with an anesthesia technician present. Receives: Drug: Standard-dose balanced propofol analgosedation |
| Dose-sparing balanced propofol analgosedation | Experimental | Intravenous midazolam 0.05 mg/kg (maximum 5 mg), followed by fentanyl 0.001 mg/kg and an initial propofol bolus of 0.5 mg/kg. Additional propofol boluses of 10-30 mg were administered according to clinical need. Sedation and monitoring were guided by a gastroenterologist trained in advanced life support and airway management, with an anesthesia technician present and an anesthesiologist immediately available if required. Receives: Drug: Dose-sparing balanced propofol analgosedation |
What is being measured
The primary outcome is the main question the study is designed to answer.
Patient satisfaction
Patient satisfaction was assessed using a study-specific four-item questionnaire. Two items assessed satisfaction with the colonoscopy procedure and satisfaction with analgosedation using separate 11-point numerical rating scales ranging from 0 (completely dissatisfied) to 10 (extremely satisfied). Two additional binary items assessed whether the participant would recommend the same approach to relatives or friends and whether the participant would agree to undergo colonoscopy using the same approach again.
Measured: At completion of post-procedural recovery on the day of colonoscopy.
Incidence of clinically relevant respiratory adverse events
Incidence of protocol-defined respiratory adverse events, reported by event type. Respiratory events included apnea lasting more than 30 seconds, oxygen saturation below 90%, respiratory rate below 10 or above 20 breaths per minute, end-tidal CO2 below 35 mmHg, and the need for airway-opening interventions. Apnea lasting more than 30 seconds was analyzed as the principal respiratory safety endpoint.
Measured: From administration of sedation through completion of monitored post-procedural recovery on the day of colonoscopy.
Secondary outcomes (17)
Total propofol dose
Total cumulative dose of propofol administered during the colonoscopy, expressed in milligrams.
Measured: From initial propofol administration until completion of the colonoscopy.
Number of additional propofol boluses
Number of additional propofol boluses administered after the initial protocol-defined propofol dose.
Measured: From initial propofol administration until completion of the colonoscopy.
Cumulative additional propofol dose
Total cumulative dose of additional propofol administered after the initial protocol-defined propofol dose, expressed in milligrams.
Measured: From initial propofol administration until completion of the colonoscopy.
Early recovery time
Time from completion of the colonoscopy until achievement of the predefined early post-anaesthesia recovery criterion based on the Modified Aldrete Score.
Measured: From completion of colonoscopy through the early post-procedural recovery period on the day of the procedure.
Total recovery time
Time from completion of the colonoscopy until achievement of predefined discharge-readiness criteria based on post-anaesthesia recovery assessment, including the Post-Anesthesia Discharge Scoring System (PADSS).
Measured: From completion of colonoscopy until completion of monitored post-procedural recovery on the day of the procedure.
Cecal intubation rate
Proportion of colonoscopies in which the colonoscope was successfully advanced to the cecum.
Measured: During colonoscopy.
Cecal intubation time
Time from insertion of the colonoscope until successful intubation of the cecum.
Measured: During the index colonoscopy.
Colonoscope withdrawal time
Time from initiation of colonoscope withdrawal from the cecum until completion of the examination.
Measured: During colonoscopy.
Adenoma detection rate
Proportion of participants in whom at least one colorectal adenoma was detected during the index colonoscopy and confirmed by histopathological examination.
Measured: During the index colonoscopy, with histopathological confirmation following the procedure.
Colorectal cancer detection rate
Proportion of participants in whom colorectal cancer was detected during the index colonoscopy and confirmed by histopathological examination.
Measured: During the index colonoscopy, with histopathological confirmation following the procedure.
Endoscopist satisfaction
Endoscopist-reported satisfaction with procedural conditions assessed using a 11-point numerical rating scale, with higher scores indicating greater satisfaction.
Measured: Immediately after completion of colonoscopy.
Incidence of clinically relevant cardiovascular adverse events
Incidence of protocol-defined cardiovascular adverse events, reported by event type, including systolic blood pressure below 90 mmHg, heart rate below 50 or above 110 beats per minute, and clinically relevant arrhythmias.
Measured: From administration of sedation through completion of monitored post-procedural recovery on the day of colonoscopy.
Depth of sedation assessed by qCON
Depth of sedation assessed using the qCON index derived from processed electroencephalographic monitoring. qCON values range from 0 to 99, with lower values indicating deeper levels of sedation or hypnosis.
Measured: From baseline before sedation through completion of the colonoscopy, assessed at predefined intervals.
Nociception-related response assessed by qNOX
Nociception-related response assessed using the qNOX index derived from processed electroencephalographic monitoring. qNOX values range from 0 to 99, with lower values indicating a lower probability of response to noxious stimulation.
Measured: From baseline before sedation through completion of the colonoscopy, assessed at predefined intervals.
Clinical depth of sedation
Clinical depth of sedation assessed using the Modified Wilson Sedation Scale at predefined intervals during the procedure.
Measured: From administration of sedation through completion of the colonoscopy.
Patient anxiety assessed using the Endler Multidimensional Anxiety Scales (EMAS)
Patient anxiety was assessed using the Endler Multidimensional Anxiety Scales (EMAS). Trait anxiety was assessed using the EMAS-T during the initial study interview. State anxiety was assessed using the EMAS-S immediately before colonoscopy and again 48-72 hours after the procedure.
Measured: At the initial study interview, immediately before colonoscopy, and 48-72 hours after colonoscopy.
Patient pain assessed using the Brief Pain Inventory (BPI)
Patient-reported pain was assessed using the Brief Pain Inventory (BPI). The long form was completed during the initial study interview, while the short form was completed immediately before colonoscopy and again 48-72 hours after the procedure. BPI measures pain severity and pain-related interference, with higher scores indicating greater pain severity or interference.
Measured: At the initial study interview, immediately before colonoscopy, and 48-72 hours after colonoscopy.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Oct 2026
- Study start5 Jun 2022
- Primary completion3 Feb 2024
- Study completion8 Feb 2024
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for ColonoscopyStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Supportive care
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Participants were randomized in an intended 1:1 ratio to a standard-dose balanced propofol analgosedation protocol or a structured dose-sparing protocol. Allocation was performed using sealed opaque envelopes prepared before enrollment. Participants were blinded to study-group allocation. Because of the nature of the intervention, sedation providers and the procedural team were not blinded.
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 76 participants (actual)
Sponsor and investigators
- Lead sponsor
- University of Split, School of Medicine
- Sponsor type
- University, hospital or other
- Collaborators
- University Hospital of Split
- Responsible party
- Sponsor
- Investigators
- Zarko Ardalic, MD, Principal investigator, University Hospital of Split
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07885059
- Sponsor's protocol ID
- PROP-MIDFEN-RCT-2022
- Status last verified
- Oct 2026
- First submitted
- 13 Oct 2026
- Last updated
- 21 Oct 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: Deidentified individual participant data that underlie the results reported in the primary publication will be made available to qualified researchers upon reasonable request, subject to approval by the study investigators and applicable institutional, ethical, and data-protection requirements.