The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been endorsed by the ANZCTR. Before participating in a study, talk to your health care provider and refer to this information for consumers
Trial registered on ANZCTR


Registration number
ACTRN12616000668404
Ethics application status
Approved
Date submitted
21/04/2016
Date registered
23/05/2016
Date last updated
19/03/2021
Date data sharing statement initially provided
26/02/2020
Date results information initially provided
26/02/2020
Type of registration
Prospectively registered

Titles & IDs
Public title
A comparative study of the efficacy of the McGrath (Registered Trademark) X-blade vs the C-MAC Videolaryngoscope in patients with simulated difficult airways
Scientific title
A comparative study of the efficacy of the McGrath (Registered Trademark) X-blade vs the C-MAC Videolaryngoscope in patients with simulated difficult airways
Secondary ID [1] 288749 0
Nil
Universal Trial Number (UTN)
Trial acronym
None
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Difficult Airway 297993 0
Condition category
Condition code
Anaesthesiology 298149 298149 0 0
Other anaesthesiology

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Use of the new X-blade attachment for the McGrath videolaryngoscope in patients undergoing general anaesthesia requiring tracheal intubation, with simulated difficult airway by manual in-line cervical stabilisation.
The procedure will begin 3 minutes after the induction of general anaesthesia, before surgery could proceed. Once tracheal intubation is achieved, surgery will be allowed to commence at any time thereafter.
The intervention is delivered by 3 anaesthesiology specialists and 2 senior anaesthesiology residents, all of whom have 5/more years of experience in anaesthesiology.
The study device (X-blade) is an angulated blade attachment for the McGrath cideolaryngoscope, with a curvature of 60 degrees. The control device (C-MAC videolarygoscope) has a lesser curvature of approx 30-40 degrees. Hence the view of the glottis obtained with the 2 blades are slightly different.
Intervention code [1] 294183 0
Treatment: Devices
Comparator / control treatment
The control device is the C-MAC videolaryngoscope in patients undergoing general anaesthesia requiring tracheal intubation, with simulated difficult airway by manual in-line cervical stabilisation
Control group
Active

Outcomes
Primary outcome [1] 297654 0
First pass success (FPS) at intubation.

This is defined as the successful intubation of the trachea on the 1st attempt, confirmed by the presence of end-tidal carbon dioxide tracing on the capnography monitor, and also by clinical auscultation of the lungs.
Timepoint [1] 297654 0
in patients undergoing general anaesthesia requiring tracheal intubation, with simulated difficult airway by manual in-line cervical stabilisation

Timepoint = during intubation
Secondary outcome [1] 321712 0
overall intubation success

This is defined as the overall success of intubation with the device. Intubation is confirmed by the presence of end-tidal carbon dioxide tracing on the capnography monitor, and also by clinical auscultation of the lungs.
Timepoint [1] 321712 0
overall intubation success

Timepoint = during intubation
Secondary outcome [2] 321713 0
number of intubation attempts

Each intubation attempt is defined as each time the laryngoscope blade enters the patient's mouth till a successful intubation.
Timepoint [2] 321713 0
number of intubation attempts

Timepoint = during intubation
Secondary outcome [3] 321714 0
total time to intubation

This is defined as the time from laryngoscope insertion to the presence of the 1st end-tidal CO2 waveform on the monitor, and is inclusive of the time taken for removal of laryngoscope and bag mask ventilation in between attempts.
Timepoint [3] 321714 0
Timepoint = during intubation
Secondary outcome [4] 321715 0
Cormack & Lehane grade, which describes the quality of the view of the vocal cords during laryngoscopy.
Timepoint [4] 321715 0
During intubation
Secondary outcome [5] 321716 0
cardiovascular adverse outcome of more than 20% increase in heart rate from baseline, as measured on the patient monitor
Timepoint [5] 321716 0
During intubation
Secondary outcome [6] 323634 0
cardiovascular adverse outcome of more than 20% increase in blood pressure from baseline, as measured on the patient monitor
Timepoint [6] 323634 0
During intubation
Secondary outcome [7] 323635 0
respiratory adverse outcome of desaturation to less than 91%, as measured on the patient monitor
Timepoint [7] 323635 0
during intubation
Secondary outcome [8] 323636 0
intubation related adverse outcome of blood present on laryngoscope - the laryngoscope will be inspected for presence of blood after intubation. Presence of blood indicates a positive complication
Timepoint [8] 323636 0
during intubation
Secondary outcome [9] 323637 0
intubation related adverse outcome of oropharyngeal trauma (e.g. laceration/ulceration) noted during laryngoscopy
Timepoint [9] 323637 0
during intubation
Secondary outcome [10] 323638 0
intubation related adverse outcome of postoperative sore throat, graded in terms of severity (mild, moderate, severe)
Timepoint [10] 323638 0
after surgery when patient is in the recovery unit
Secondary outcome [11] 323639 0
intubation related adverse outcome of postoperative hoarseness of voice - patient will be asked specifically for subjective presence of hoarseness of voice after surgery
Timepoint [11] 323639 0
after surgery when patient is in the recovery unit
Secondary outcome [12] 323640 0
intubation related adverse outcome of blood-stained secretions - expectorated secretions will be inspected for blood stains during monitoring in recovery unit
Timepoint [12] 323640 0
after surgery when patient is in the recovery unit

Eligibility
Key inclusion criteria
1. Age between 21 to 80 years old
2. American Society of Anaesthesiologists (ASA) Physical Status Class I to III
3. Elective operations requiring general anaesthesia and tracheal intubation
Minimum age
21 Years
Maximum age
80 Years
Sex
Both males and females
Can healthy volunteers participate?
No
Key exclusion criteria
1. Clinical evidence of difficult airway:
a. Mallampathi Class 3 & 4
b. Thyromental distance <6cm
c. Interincisor distance < 3.5cm
d. Previous documented difficult laryngoscopy or bag mask ventilation
2. Pre-existing dental risks e.g. loose tooth
3. Morbidly obese patients with BMI > 35kg/m2
4. Pre-existing cervical spondylosis/ myelopathy
5. Aspiration risks (unfasted, GERD, hiatus hernia)
6. where awake tracheal intubation is indicated
7. Patients who refuse to participate or lack the capacity to give consent

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)
The device assignment is enclosed in sequentially numbered, opaque, sealed envelopes, which will not be opened until the patient is anaethestised.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Subjects will be randomized using a computer-generated random table.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

The people assessing the outcomes
Intervention assignment
Parallel
Other design features
Phase
Not Applicable
Type of endpoint/s
Efficacy
Statistical methods / analysis
Upon planning of the trial’s protocol, there were no published studies involving the McGrath X-blade in the clinical setting and very few studies examining the first-pass success of the CMAC videolaryngoscope in patients with cervical spine immobilization. A first-pass success of 90% with the CMAC was previously demonstrated in such patients. Taking a 10% difference in FPS with the McGrath X-blade as clinically significant, and accounting for a 5% drop-out rate, a sample size of 210 (105 per group) was calculated, with a desired power of 90% and an alpha-error of 0.05.

Continuous variables will be presented as mean (standard deviation) or median (interquartile range) after assessing normality. Categorical variables will be summarised using frequency (percentage). Depending on the normality of continuous outcome variables, independent student’s t-test or Mann-Whitney U test will be conducted to compare means or medians between two groups. The chi-square test or Fisher’s exact test will be used for comparison of categorical variables when appropriate. General linear model for repeated measures will be used for analysis of hemodynamic variables

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] 7701 0
Singapore
State/province [1] 7701 0
singapore

Funding & Sponsors
Funding source category [1] 293102 0
Hospital
Name [1] 293102 0
Khoo Teck Puat Hospital
Country [1] 293102 0
Singapore
Primary sponsor type
Individual
Name
Zhang Jinbin
Address
Tan Tock Seng Hospital
11 Jalan Tan Tock Seng
Singapore 308433
Country
Singapore
Secondary sponsor category [1] 291891 0
None
Name [1] 291891 0
Address [1] 291891 0
Country [1] 291891 0
Other collaborator category [1] 278886 0
Individual
Name [1] 278886 0
Edwin Seet
Address [1] 278886 0
Khoo Teck Puat Hospital
90 Yishun Central
Singapore 768828

Country [1] 278886 0
Singapore

Ethics approval
Ethics application status
Approved
Ethics committee name [1] 294605 0
Domain Specific Review Board
Ethics committee address [1] 294605 0
Domain Specific Review Board (DSRB)
Domain Specific Review Board
c/o National Healthcare Group, Research & Development Office (RDO)
Nexus @One-North (South Tower), No. 3 Fusionopolis Link, #03-08,
Singapore 138543

Ethics committee country [1] 294605 0
Singapore
Date submitted for ethics approval [1] 294605 0
05/08/2015
Approval date [1] 294605 0
21/04/2016
Ethics approval number [1] 294605 0
2015/00991

Summary
Brief summary
Videolaryngoscopes have been listed as part of the initial approach to intubation in international airway algorithms and guidelines, such as the 2013 ASA Practice Guidelines for Management of the Difficult Airway. Furthermore, meta-analyses of RCTs comparing video-assisted laryngoscopy with direct laryngoscopy in patients with simulated difficult airways report improved laryngeal views and a higher frequency of successful intubations. The McGrath X-blade, which is recently launched in June 2014, has been advocated to be useful in difficult airway situations. In addition, it is small and easily transportable for many clinical settings for tracheal intubation. Methodology - Our null hypothesis is that McGrath X-blade attachment is as efficacious as the C-MAC Videolaryngoscope in tracheal intubation of patients with simulated difficult airways. We aim to recruit 210 patients between 21 to 80 years old, ASA I to III to receive either CMAC or McGrath X-blade for intubation during elective operations. The primary outcome will be first-pass success (FPS). Secondary outcomes include overall intubation success, number of intubation attempts, total time to intubation (TTI), Cormack & Lehane grade, cardiorespiratory and intubation-related adverse events. Importance of proposed research to science or medicine If the McGrath X-blade video laryngoscope is shown to be better in efficacy to the C-MAC Videolaryngoscope in simulated difficult airway, it will be a useful portable airway adjunct in difficult airway situations, especially those occurring in remote locations e.g. radiology suites, general ward, ICUs, where access to difficult intubation equipment may be limited. Potential benefits & risks Risks to participants are no greater than what they would experience coming for a standard general anaesthetic and tracheal intubation. General risks related to tracheal intubation included sore throat, hoarseness of voice. Uncommon risks include dental injuries and rare but severe risks include hypoxia, increased blood pressure and heart rates.
Trial website
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 64338 0
Dr Zhang Jinbin
Address 64338 0
Tan Tock Seng Hospital
11 Jalan Tan Tock Seng
Singapore 308433
Country 64338 0
Singapore
Phone 64338 0
+6596542281
Fax 64338 0
Email 64338 0
Contact person for public queries
Name 64339 0
Dr Zhang Jinbin
Address 64339 0
Tan Tock Seng Hospital
11 Jalan Tan Tock Seng
Singapore 308433
Country 64339 0
Singapore
Phone 64339 0
+6536577771
Fax 64339 0
Email 64339 0
Contact person for scientific queries
Name 64340 0
Dr Zhang Jinbin
Address 64340 0
Tan Tock Seng Hospital
11 Jalan Tan Tock Seng
Singapore 308433
Country 64340 0
Singapore
Phone 64340 0
+6596542281
Fax 64340 0
Email 64340 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No
No/undecided IPD sharing reason/comment
participant Data protection


What supporting documents are/will be available?

No Supporting Document Provided



Results publications and other study-related documents

Documents added manually
TypeIs Peer Reviewed?DOICitations or Other DetailsAttachment
Basic resultsNo 370320-(Uploaded-25-02-2020-18-02-48)-Basic results summary.docx

Documents added automatically
SourceTitleYear of PublicationDOI
EmbaseComparing the first-attempt tracheal intubation success of the hyperangulated McGrath X-blade vs the Macintosh-type CMAC videolaryngoscope in patients with cervical immobilization: a two-centre randomized controlled trial.2022https://dx.doi.org/10.1007/s10877-021-00746-5
N.B. These documents automatically identified may not have been verified by the study sponsor.