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Trial registered on ANZCTR


Registration number
ACTRN12615001267549
Ethics application status
Approved
Date submitted
12/11/2015
Date registered
19/11/2015
Date last updated
7/05/2018
Type of registration
Prospectively registered

Titles & IDs
Public title
A single-centre, randomised controlled pilot trial comparing performance of direct laryngoscopy versus videolaryngoscopy for endotracheal intubation in surgical patients (MAC-V trial)
Scientific title
A single-centre, randomised controlled pilot trial comparing performance of direct laryngoscopy versus videolaryngoscopy for endotracheal intubation in surgical patients (MAC-V trial)
Secondary ID [1] 287800 0
nil known
Universal Trial Number (UTN)
U1111-1176-3641
Trial acronym
MAC-V
Linked study record

Health condition
Health condition(s) or problem(s) studied:
patients undergoing surgery who require endotracheal intubation 296684 0
Condition category
Condition code
Anaesthesiology 296915 296915 0 0
Anaesthetics

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Patients will be randomised to be intubated using either a direct laryngoscopy or videolaryngoscopy. The intervention (intubation using either direct laryngoscopy or videolaryngoscopy) will be a single event utilising standard intubating techniques (induction of anaesthesia and muscle relaxation) at the start of surgery requiring intubation. The sole difference between the groups will be the laryngoscopy technique used.
Duration of intervention will be less than 15 minutes
Intervention code [1] 293198 0
Treatment: Devices
Comparator / control treatment
Direct laryngoscopy
Control group
Active

Outcomes
Primary outcome [1] 296527 0
Incidence of first pass endotracheal intubation. A successful first-pass intubation was defined as a fluid movement from when the endotracheal tube enters the mouth to when it has been positioned during the vocal cords during a single apnoeic episode. Airway adjuncts such as bougie or stylet may be used as could assistance with optimal external laryngeal manipulation (OELM) or suctioning but these must be performed prior the the endotracheal tube entering the patient’s oropharynx. Curtailing the attempt for bag-mask ventilation, repositioning, assistance or additional equipment to those already specified was deemed failure. Attempting to pass the tube multiple times (more than twice without success) without adjusting the laryngoscope was also deemed as unsuccessful.
Timepoint [1] 296527 0
at intervention
Secondary outcome [1] 318677 0
Time to first pass endotracheal intubation.
Time to first-pass intubation is defined as the time taken from when the intubator takes the laryngoscope to when endotracheal tube placement is confirmed and end tidal CO2 is recorded on capnography waveform. This will be timwed using a stopwatch.
Timepoint [1] 318677 0
at intervenion. This is from when the intubator takes the laryngoscope to when endotracheal tube placement is confirmed and end tidal CO2 is recorded on capnography waveform. Please see specific definition above.
Secondary outcome [2] 318678 0
performance of techniques measured by intubation difficulty score (IDS)
Timepoint [2] 318678 0
immediately following intervention
Secondary outcome [3] 318679 0
patient harm measured by composite of airway bleeding, mucosal injury and dental damage reported in post anaesthetic care uint
Timepoint [3] 318679 0
immediately after intervention

Eligibility
Key inclusion criteria
Adult patient scheduled for surgery requiring asleep endotracheal intubation
No contra-indication to direct laryngoscopy or videolaryngoscopy
Laryngoscopy for endotracheal intubation is required
Minimum age
18 Years
Maximum age
No limit
Gender
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
Unable/ Unwilling to consent
Known previous difficult intubation
Emergency surgery
Clinical scenarios where awake or asleep fibreoptic inbutation is the technique of choice
Operating anaesthetist has performed less than 20 videolaryngoscopies

Study design
Purpose of the study
Treatment
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Those meeting inclusion criteria and lacking exclusion criteria will be invited to participate in the study.
Following provision of informed consent subjects will be allocated to one of the two treatment groups . Group assignment will be by random concealed allocation, this will be carried out using sealed opaque envelopes.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Permuted block randomisation
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint(s)
Safety/efficacy
Statistical methods / analysis
We estimate a total of 100 patients will be adequate to test feasibility endpoints but not adequate for the primary endpoint. We estimate from previously published data that the first-pass intubation rates will be approximately 85%. We believe a clinically important absolute difference would be 5%.
To find a 5% absolute difference between the performances of laryngoscopy blades we calculated that the sample size of 1480 (alpha= 0.05 and beta= 0.2) or 1940 (alpha=0.05 and beta 0.1) would be needed. Please refer to table in attachments section on page 9 to see calculations.
Responses will be collected and collated using Microsoft Excel and statistical analysis will be carried out using SAS v9.3 for Windows. Categorical variables will be compared using the X^2 analysis; and continuous variables using Students t-test or ANOVA for normally distributed variables; non-normally distributed variables will be transformed or analysed using non-parametric statistics as appropriate.

Recruitment
Recruitment status
Completed
Date of first participant enrolment
Anticipated
Actual
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
Actual
Sample size
Target
Accrual to date
Final
Recruitment outside Australia
Country [1] 7294 0
New Zealand
State/province [1] 7294 0
Auckland

Funding & Sponsors
Funding source category [1] 292332 0
Government body
Name [1] 292332 0
Auckland District Health Board
Address [1] 292332 0
Department of Anaesthesia
Level 8 Support Building
Auckland City Hospital
2 Park Road, Grafton
Auckland
1023
Country [1] 292332 0
New Zealand
Primary sponsor type
Government body
Name
Auckland District Health Board
Address
Department of Anaesthesia
Level 8 Support Building
Auckland City Hospital
2 Park Road, Grafton
Auckland
1023
Country
New Zealand
Secondary sponsor category [1] 291011 0
None
Name [1] 291011 0
Address [1] 291011 0
Country [1] 291011 0

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 293797 0
Ethics committee address [1] 293797 0
Ethics committee country [1] 293797 0
Date submitted for ethics approval [1] 293797 0
12/11/2015
Approval date [1] 293797 0
27/01/2016
Ethics approval number [1] 293797 0

Summary
Brief summary
Approximately half of patients having general anaesthesia require endotracheal intubation to allow muscle relaxation, control ventilation or protect the airway. Historically, this has been achieved mostly by direct laryngoscopy with a laryngoscope. In the last 20 years, videolaryngoscopy has been used increasingly with many anaesthetists favouring its use. The two techniques are in widespread use and anaesthetists are expected to be familiar with both. There is increasing evidence that videolaryngoscopy provides superior view of the glottic opening. However, this is a surrogate endpoint and there seems to be a poor relationship between view and intubation success with many videolaryngoscopic devices. A large, pragmatic clinical trial powered for intubation success has never been performed. Current randomised control trials comparing these methods are small, use different endpoints, and specific populations, making results less generalisable. Furthermore meta analyses comparing these devices have rarely collected data relating to harm that could be consequent to their use. We believe the most meaningful endpoint to determine the performance of these devices is first pass intubation, that is, the first attempt to intubate being successful. This single-centre study aims to compare direct larygoscopy with videolaryngoscopy using first pass intubation success as the primary endpoint. We aim to test the feasibility of a large, multicentre effectiveness trial by recruiting 100 trial participants. We aim to compare the relative harms of the different laryngoscopic techniques. The results of this trial will provide improved guidance for current airway algorithms
Trial website
Trial related presentations / publications
Public notes
Attachments [1] 637 637 0 0

Contacts
Principal investigator
Name 61358 0
Dr Alice Loughnan
Address 61358 0
Department of Anaesthesia
Level 8 Support Building
Auckland City Hospital
2 Park Road, Grafton
Auckland
1023
Country 61358 0
New Zealand
Phone 61358 0
+6493670000
Fax 61358 0
Email 61358 0
alice.loughnan@btinternet.com
Contact person for public queries
Name 61359 0
Ms Davina Mcallister
Address 61359 0
Department of Anaesthesia
Level 8 Support Building
Auckland City Hospital
2 Park Road, Grafton
Auckland
1023
Country 61359 0
New Zealand
Phone 61359 0
+6493757095
Fax 61359 0
Email 61359 0
davinams@adhb.govt.nz
Contact person for scientific queries
Name 61360 0
Dr Douglas Campbell
Address 61360 0
Department of Anaesthesia
Level 8 Support Building
Auckland City Hospital
2 Park Road, Grafton
Auckland
1023
Country 61360 0
New Zealand
Phone 61360 0
+6493670000
Fax 61360 0
Email 61360 0
dcampbell@adhb.govt.nz

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