Induction of AnaesthesiaPhase 4NCT02287181
A Phase IV Study Investigating the Effects of Remifentanil Concentrations on Propofol Requirements for Loss of Consciousness, Response to Painful Stimuli, Bispectral Index and Associated Haemodynamic Changes
A Phase 4 study testing Remifentanil, Propofol and Bispectral index in people with Induction of Anaesthesia, run by The University of Hong Kong at 1 site in Hong Kong.
Trial summary
A prospective, randomised, phase IV trial including 150 patients. To evaluate the effects of varied concentrations of remifentanil on the proposal requirements for the loss of consciousness and response to pain and to evaluate the haemodynamic changes and processed EEG (BIS) during induction of anaesthesia. Read more about this study
- Who is it for?
- Ages 18 to 65 yearsHealthy volunteers can take part
- Conditions the study is for
- Induction of Anaesthesia
- What is being tested?
- Remifentanil, Propofol and Bispectral index
- Type of treatment
- Injection or infusion
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteHong Kong
- Study dates
- Feb 2015to Aug 2015
- Phase
- Phase 4
- Are there results?
- None posted in the registry
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
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- ASA I or II patients (healthy or with mild systemic illness) undergoing planned surgery requiring general anaesthetic
Who cannot join
- Subjects with pre-existing neurological or psychiatric illness.
- Subjects on CNS acting medication or analgesics.
Trial locations and contacts
1 site in 1 country.
About this study
Official title: A Phase IV Study to Investigate the Effects of Varied Remifentanil Concentrations on Propofol Requirements for Loss of Consciousness, Response to Painful Stimuli, Bispectral Index and Associated Haemodynamic Changes
A prospective, randomised, phase IV trial including 150 patients.
To evaluate the effects of varied concentrations of remifentanil on the proposal requirements for the loss of consciousness and response to pain and to evaluate the haemodynamic changes and processed EEG (BIS) during induction of anaesthesia.
Read the detailed description
BackGround
The combination of remifentanil and propofol infusions is a widely used method of total intravenous anaesthesia. (1) Target controlled infusion (TCI) is a pharmacokinetic (PK) infusion system using data from a large population of patients to calculate and deliver stable concentrations of a drug based on a three compartment PK model. Both propofol and remifentanil are ideal drugs for delivery in this way because of their quick distribution, metabolism and excretion. (2) Remifentanil is a potent synthetic opioid receptor (MOR) agonist with a short recovery irrespective of the duration of its administration. This is due to it being quickly broken down by non-specific esterases in blood and tissues. (3) Remifentanil like all opioids is not very hypnotic in clinically relevant concentrations. (4)
Remifentanil has been shown to reduce propofol requirements during induction and maintenance of anaesthesia. (5)(6) Also modest doses of remifentanil markedly reduce the amount of propofol required to ablate response to painful stimuli. The relationship between propofol and remifentanil has been reported as synergistic but additive when using propofol concentrations within the clinical range. (7)(8) However in other studies, BIS has shown no interaction between propofol and remifentanil (9)(10) A correlation between BIS, painful stimuli and other opioids has been demonstrated. (11) It has been suggested that BIS values can change with propofol and painful stimuli and this can aid administration of remifentanil in a dose dependent manner. (12) Since propofol and remifentanil are ubiquitously used together, the interaction between these drugs and EEG needs to be defined in more detail.
Trial Objectives To see whether remifentanil affects the dose of proposal required for loss of consciousness and loss of response to painful stimuli and whether this is reflected in changes in brain EEG (bispectral index BIS)
Hypothesis That the effect site concentration of proposal at loss of consciousness will only be moderately affected by concurrently remifentanil infusion but BIS will not change. That the clinical response to painful stimuli will markedly decrease when there is concurrent infusion of remifentanil. With painful stimuli there will be an increase in BIS but this will be blocked by remifentanil.
Methodology From the start date of the study, the first 100 patients eligible will be included. Patients will be allocated into one of two groups, group A or group B by a computer generated randomization table.
For each patient, after receiving written consent, the patient will enter the theatre where they are going to have their elective operation. Standard anaesthetic monitoring will be applied, plus a BIS monitor. External peripheral nerve stimuli electrodes will be placed over the ulner nerve on the dominant arm. IV access will be gained by the anaesthetist. All infusions will run through the same IV cannula using standardized one way valves.
One anaesthetist will look after the air way while the second anesthetist or a research assistant will fill in the data collection sheet and determine point of loss of consciousness and point of loss of response to painful stimuli. The air way anesthetist will know by a sealed envelope whether the patient is on group A or B. For the patients in group A, the remifentanil infusion, using the minto effect site concentration model, will be set at 0ng/ml. For the patients in group B the remifentanil infusion will be set at 3ng/ml. After 5 minutes the propofol infusion will commence, using the Marsh effect site concerntration TCI model, at 1mcg/ml and will be increased by 0.2mcg/ml every one minute. Heart Rate, blood pressure and BIS number will be recorded every minute. Every 30 seconds the anaesthetist will prompt the patient with the vocal stimuli "say your name" in a constant tone and volume. Loss of consciousness will be defined as the point at which the patient fails to respond to the vocal stimuli and light tactite stilulation. At this point BIS, heart rate, blood pressure and propofol effect site concentration will be recorded.
After loss of consciousness, a tetanic stimuli will be applied using the peripheral nerve stimulator and repeated every thirty seconds. The propofol infusion will continue to be increased every one minutes by 0.2mcg/ml. Loss of response to painful stimuli will be defined as the point at which the patient fails to make a withdrawal motion from the tetanic stimulation. Here, heart rate, blood pressure BIS number and propofol effect site concentration will be recorded.
After loss of response to painful stimuli the study is complete, no further date will be collected, the peripheral nerve stimulator will be removed, the anaesthesia will continue and surgery will commence as usual.
- Conditions
- Induction of Anaesthesia
- Being tested
- Remifentanil, Propofol, Bispectral index
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
RemifentanilDrug
short acting opiate
PropofolDrug
hypnotic drug
Bispectral indexOther
electroencephalograph
| Study group | Role | What they receive |
|---|---|---|
| remifentanil effect site concentration 0ng/ml | Active comparator | remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 0 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli. Receives: Drug: Remifentanil; Drug: Propofol; Other: Bispectral index |
| remifentanil effect site concentration 3ng/ml | Active comparator | remifentanil run as an infusion using the minto TCI model, at an effect site concentration of 3 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli. Receives: Drug: Remifentanil; Drug: Propofol; Other: Bispectral index |
What is being measured
The primary outcome is the main question the study is designed to answer.
Effect site concentration of propofol at time of loss of consciousness for each of the two groups
Measured: every 1 minute up to 40 minutes
Effect site concentration of propofol at loss of response to painful stimuli for each of the three groups
Measured: every 1 minute up to 40 minutes
Secondary outcomes (4)
Time to loss of consciousness
Measured: every 1 minute up to 40 minutes
EEG Bispectral index BIS
Measured: every 1 minute up to 40 minutes
heart rate
Measured: every 1 minute up to 40 minutes
blood pressure
Measured: every 1 minute up to 40 minutes
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted10 Nov 2014 (estimated)
- Study startFeb 2015
- Primary completionAug 2015
- Study completionAug 2015
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (11)Papers the sponsor has linked to this study.
- Other trials for Induction of AnaesthesiaStudies of the same condition, open and under way.
- More trials run by The University of Hong KongThe sponsor's other registered studies.
- 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 4
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 100 participants (actual)
Sponsor and investigators
- Lead sponsor
- The University of Hong Kong
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Hannah Scott, The University of Hong Kong
- Investigators
- Michael Irwin, MbChB, Study chair, Hong Kong University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT02287181
- Sponsor's protocol ID
- uhongkong
- Status last verified
- Mar 2015
- First submitted
- 24 Oct 2014
- Last updated
- 11 Mar 2016
- Results posted
- No
Publications
Vuyk J, Mertens MJ, Olofsen E, Burm AG, Bovill JG. Propofol anesthesia and rational opioid selection: determination of optimal EC50-EC95 propofol-opioid concentrations that assure adequate anesthesia and a rapid return of consciousness. Anesthesiology. 1997 Dec;87(6):1549-62. doi: 10.1097/00000542-199712000-00033. No abstract available.
PubMed 9416739Absalom AR, Mani V, De Smet T, Struys MM. Pharmacokinetic models for propofol--defining and illuminating the devil in the detail. Br J Anaesth. 2009 Jul;103(1):26-37. doi: 10.1093/bja/aep143. Epub 2009 Jun 10.
PubMed 19520702Minto CF, Schnider TW, Egan TD, Youngs E, Lemmens HJ, Gambus PL, Billard V, Hoke JF, Moore KH, Hermann DJ, Muir KT, Mandema JW, Shafer SL. Influence of age and gender on the pharmacokinetics and pharmacodynamics of remifentanil. I. Model development. Anesthesiology. 1997 Jan;86(1):10-23. doi: 10.1097/00000542-199701000-00004.
PubMed 9009935Iselin-Chaves IA, Flaishon R, Sebel PS, Howell S, Gan TJ, Sigl J, Ginsberg B, Glass PS. The effect of the interaction of propofol and alfentanil on recall, loss of consciousness, and the Bispectral Index. Anesth Analg. 1998 Oct;87(4):949-55. doi: 10.1097/00000539-199810000-00038.
PubMed 9768800Mertens MJ, Olofsen E, Engbers FH, Burm AG, Bovill JG, Vuyk J. Propofol reduces perioperative remifentanil requirements in a synergistic manner: response surface modeling of perioperative remifentanil-propofol interactions. Anesthesiology. 2003 Aug;99(2):347-59. doi: 10.1097/00000542-200308000-00016.
PubMed 12883407Jee YS, Hong JY. Effects of remifentanil on propofol requirements for loss of consciousness in target-controlled infusion. Minerva Anestesiol. 2008 Jan-Feb;74(1-2):17-22.
PubMed 18216764Bouillon TW, Bruhn J, Radulescu L, Andresen C, Shafer TJ, Cohane C, Shafer SL. Pharmacodynamic interaction between propofol and remifentanil regarding hypnosis, tolerance of laryngoscopy, bispectral index, and electroencephalographic approximate entropy. Anesthesiology. 2004 Jun;100(6):1353-72. doi: 10.1097/00000542-200406000-00006.
PubMed 15166553Ropcke H, Konen-Bergmann M, Cuhls M, Bouillon T, Hoeft A. Propofol and remifentanil pharmacodynamic interaction during orthopedic surgical procedures as measured by effects on bispectral index. J Clin Anesth. 2001 May;13(3):198-207. doi: 10.1016/s0952-8180(01)00255-0.
PubMed 11377158Guignard B, Menigaux C, Dupont X, Fletcher D, Chauvin M. The effect of remifentanil on the bispectral index change and hemodynamic responses after orotracheal intubation. Anesth Analg. 2000 Jan;90(1):161-7. doi: 10.1097/00000539-200001000-00034.
PubMed 10624998Lysakowski C, Dumont L, Pellegrini M, Clergue F, Tassonyi E. Effects of fentanyl, alfentanil, remifentanil and sufentanil on loss of consciousness and bispectral index during propofol induction of anaesthesia. Br J Anaesth. 2001 Apr;86(4):523-7. doi: 10.1093/bja/86.4.523.
PubMed 11573626Liu N, Chazot T, Hamada S, Landais A, Boichut N, Dussaussoy C, Trillat B, Beydon L, Samain E, Sessler DI, Fischler M. Closed-loop coadministration of propofol and remifentanil guided by bispectral index: a randomized multicenter study. Anesth Analg. 2011 Mar;112(3):546-57. doi: 10.1213/ANE.0b013e318205680b. Epub 2011 Jan 13.
PubMed 21233500
Study at a glance
From the registry record, last updated by the sponsor on 11 Mar 2016. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Phase IV Study to Investigate the Effects of Varied Remifentanil Concentrations on Propofol Requirements for Loss of Consciousness, Response to Painful Stimuli, Bispectral Index and Associated Haemodynamic Changes
- ClinicalTrials.gov ID
- NCT02287181
- Acronym / sponsor ID
- uhongkong
- Conditions
- Induction of Anaesthesia
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 100 participants (actual)
- Lead sponsor
- The University of Hong KongUniversity, hospital or other
- Study start
- Feb 2015
- Primary completion
- Aug 2015 (actual)
- Study completion
- Aug 2015 (actual)
- First posted
- 10 Nov 2014 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
A prospective, randomised, phase IV trial including 150 patients.
To evaluate the effects of varied concentrations of remifentanil on the proposal requirements for the loss of consciousness and response to pain and to evaluate the haemodynamic changes and processed EEG (BIS) during induction of anaesthesia.
Detailed description
BackGround
The combination of remifentanil and propofol infusions is a widely used method of total intravenous anaesthesia. (1) Target controlled infusion (TCI) is a pharmacokinetic (PK) infusion system using data from a large population of patients to calculate and deliver stable concentrations of a drug based on a three compartment PK model. Both propofol and remifentanil are ideal drugs for delivery in this way because of their quick distribution, metabolism and excretion. (2) Remifentanil is a potent synthetic opioid receptor (MOR) agonist with a short recovery irrespective of the duration of its administration. This is due to it being quickly broken down by non-specific esterases in blood and tissues. (3) Remifentanil like all opioids is not very hypnotic in clinically relevant concentrations. (4)
Remifentanil has been shown to reduce propofol requirements during induction and maintenance of anaesthesia. (5)(6) Also modest doses of remifentanil markedly reduce the amount of propofol required to ablate response to painful stimuli. The relationship between propofol and remifentanil has been reported as synergistic but additive when using propofol concentrations within the clinical range. (7)(8) However in other studies, BIS has shown no interaction between propofol and remifentanil (9)(10) A correlation between BIS, painful stimuli and other opioids has been demonstrated. (11) It has been suggested that BIS values can change with propofol and painful stimuli and this can aid administration of remifentanil in a dose dependent manner. (12) Since propofol and remifentanil are ubiquitously used together, the interaction between these drugs and EEG needs to be defined in more detail.
Trial Objectives To see whether remifentanil affects the dose of proposal required for loss of consciousness and loss of response to painful stimuli and whether this is reflected in changes in brain EEG (bispectral index BIS)
Hypothesis That the effect site concentration of proposal at loss of consciousness will only be moderately affected by concurrently remifentanil infusion but BIS will not change. That the clinical response to painful stimuli will markedly decrease when there is concurrent infusion of remifentanil. With painful stimuli there will be an increase in BIS but this will be blocked by remifentanil.
Methodology From the start date of the study, the first 100 patients eligible will be included. Patients will be allocated into one of two groups, group A or group B by a computer generated randomization table.
For each patient, after receiving written consent, the patient will enter the theatre where they are going to have their elective operation. Standard anaesthetic monitoring will be applied, plus a BIS monitor. External peripheral nerve stimuli electrodes will be placed over the ulner nerve on the dominant arm. IV access will be gained by the anaesthetist. All infusions will run through the same IV cannula using standardized one way valves.
One anaesthetist will look after the air way while the second anesthetist or a research assistant will fill in the data collection sheet and determine point of loss of consciousness and point of loss of response to painful stimuli. The air way anesthetist will know by a sealed envelope whether the patient is on group A or B. For the patients in group A, the remifentanil infusion, using the minto effect site concentration model, will be set at 0ng/ml. For the patients in group B the remifentanil infusion will be set at 3ng/ml. After 5 minutes the propofol infusion will commence, using the Marsh effect site concerntration TCI model, at 1mcg/ml and will be increased by 0.2mcg/ml every one minute. Heart Rate, blood pressure and BIS number will be recorded every minute. Every 30 seconds the anaesthetist will prompt the patient with the vocal stimuli "say your name" in a constant tone and volume. Loss of consciousness will be defined as the point at which the patient fails to respond to the vocal stimuli and light tactite stilulation. At this point BIS, heart rate, blood pressure and propofol effect site concentration will be recorded.
After loss of consciousness, a tetanic stimuli will be applied using the peripheral nerve stimulator and repeated every thirty seconds. The propofol infusion will continue to be increased every one minutes by 0.2mcg/ml. Loss of response to painful stimuli will be defined as the point at which the patient fails to make a withdrawal motion from the tetanic stimulation. Here, heart rate, blood pressure BIS number and propofol effect site concentration will be recorded.
After loss of response to painful stimuli the study is complete, no further date will be collected, the peripheral nerve stimulator will be removed, the anaesthesia will continue and surgery will commence as usual.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
| Arm | Type | Receives |
|---|---|---|
| remifentanil effect site concentration 0ng/ml | Active comparator | Drug: Remifentanil, Drug: Propofol, Other: Bispectral indexremifentanil run as an infusion using the minto TCI model, at an effect site concentration of 0 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli. |
| remifentanil effect site concentration 3ng/ml | Active comparator | Drug: Remifentanil, Drug: Propofol, Other: Bispectral indexremifentanil run as an infusion using the minto TCI model, at an effect site concentration of 3 nano grams per millilitre, commenced from start of proposal infusion to point at which patient is anaesthetised and not responding to painful stimuli. |
Who may qualify
- Ages
- 18 to 65 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (1 listed)
- ASA I or II patients (healthy or with mild systemic illness) undergoing planned surgery requiring general anaesthetic
Key exclusion criteria (2 listed)
- Subjects with pre-existing neurological or psychiatric illness.
- Subjects on CNS acting medication or analgesics.
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Remifentanilshort acting opiate | Drug | remifentanil effect site concentration 0ng/ml, remifentanil effect site concentration 3ng/ml |
| Propofolhypnotic drug | Drug | remifentanil effect site concentration 0ng/ml, remifentanil effect site concentration 3ng/ml |
| Bispectral indexelectroencephalograph | Other | remifentanil effect site concentration 0ng/ml, remifentanil effect site concentration 3ng/ml |
Primary outcome
Effect site concentration of propofol at time of loss of consciousness for each of the two groups
Time frame: every 1 minute up to 40 minutes
Effect site concentration of propofol at loss of response to painful stimuli for each of the three groups
Time frame: every 1 minute up to 40 minutes
4 secondary outcomes
Time to loss of consciousness
Time frame: every 1 minute up to 40 minutes
EEG Bispectral index BIS
Time frame: every 1 minute up to 40 minutes
heart rate
Time frame: every 1 minute up to 40 minutes
blood pressure
Time frame: every 1 minute up to 40 minutes
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 11 Mar 2016.
- Background: PubMed 9416739Vuyk J, Mertens MJ, Olofsen E, Burm AG, Bovill JG. Propofol anesthesia and rational opioid selection: determination of optimal EC50-EC95 propofol-opioid concentrations that assure adequate anesthesia and a rapid return of consciousness. Anesthesiology. 1997 Dec;87(6):1549-62. doi: 10.1097/00000542-199712000-00033. No abstract available.
- Background: PubMed 19520702Absalom AR, Mani V, De Smet T, Struys MM. Pharmacokinetic models for propofol--defining and illuminating the devil in the detail. Br J Anaesth. 2009 Jul;103(1):26-37. doi: 10.1093/bja/aep143. Epub 2009 Jun 10.
- Background: PubMed 9009935Minto CF, Schnider TW, Egan TD, Youngs E, Lemmens HJ, Gambus PL, Billard V, Hoke JF, Moore KH, Hermann DJ, Muir KT, Mandema JW, Shafer SL. Influence of age and gender on the pharmacokinetics and pharmacodynamics of remifentanil. I. Model development. Anesthesiology. 1997 Jan;86(1):10-23. doi: 10.1097/00000542-199701000-00004.
- Background: PubMed 9768800Iselin-Chaves IA, Flaishon R, Sebel PS, Howell S, Gan TJ, Sigl J, Ginsberg B, Glass PS. The effect of the interaction of propofol and alfentanil on recall, loss of consciousness, and the Bispectral Index. Anesth Analg. 1998 Oct;87(4):949-55. doi: 10.1097/00000539-199810000-00038.
- Background: PubMed 12883407Mertens MJ, Olofsen E, Engbers FH, Burm AG, Bovill JG, Vuyk J. Propofol reduces perioperative remifentanil requirements in a synergistic manner: response surface modeling of perioperative remifentanil-propofol interactions. Anesthesiology. 2003 Aug;99(2):347-59. doi: 10.1097/00000542-200308000-00016.
- Background: PubMed 18216764Jee YS, Hong JY. Effects of remifentanil on propofol requirements for loss of consciousness in target-controlled infusion. Minerva Anestesiol. 2008 Jan-Feb;74(1-2):17-22.
- Background: PubMed 15166553Bouillon TW, Bruhn J, Radulescu L, Andresen C, Shafer TJ, Cohane C, Shafer SL. Pharmacodynamic interaction between propofol and remifentanil regarding hypnosis, tolerance of laryngoscopy, bispectral index, and electroencephalographic approximate entropy. Anesthesiology. 2004 Jun;100(6):1353-72. doi: 10.1097/00000542-200406000-00006.
- Background: PubMed 11377158Ropcke H, Konen-Bergmann M, Cuhls M, Bouillon T, Hoeft A. Propofol and remifentanil pharmacodynamic interaction during orthopedic surgical procedures as measured by effects on bispectral index. J Clin Anesth. 2001 May;13(3):198-207. doi: 10.1016/s0952-8180(01)00255-0.
- Background: PubMed 10624998Guignard B, Menigaux C, Dupont X, Fletcher D, Chauvin M. The effect of remifentanil on the bispectral index change and hemodynamic responses after orotracheal intubation. Anesth Analg. 2000 Jan;90(1):161-7. doi: 10.1097/00000539-200001000-00034.
- Background: PubMed 11573626Lysakowski C, Dumont L, Pellegrini M, Clergue F, Tassonyi E. Effects of fentanyl, alfentanil, remifentanil and sufentanil on loss of consciousness and bispectral index during propofol induction of anaesthesia. Br J Anaesth. 2001 Apr;86(4):523-7. doi: 10.1093/bja/86.4.523.
- Background: PubMed 21233500Liu N, Chazot T, Hamada S, Landais A, Boichut N, Dussaussoy C, Trillat B, Beydon L, Samain E, Sessler DI, Fischler M. Closed-loop coadministration of propofol and remifentanil guided by bispectral index: a randomized multicenter study. Anesth Analg. 2011 Mar;112(3):546-57. doi: 10.1213/ANE.0b013e318205680b. Epub 2011 Jan 13.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Michael Irwin, MbChB study chair
Hong Kong University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Remifentanil, Propofol and Bispectral index in people with Induction of Anaesthesia, run by The University of Hong Kong at 1 site in Hong Kong.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 1 inclusion and 2 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 11 Mar 2016. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Hong Kong. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Effect site concentration of propofol at time of loss of consciousness for each of the two groups (time frame: every 1 minute up to 40 minutes). The study lists 2 primary outcomes in all. It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT02287181, which also lists 11 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 11 Mar 2016.