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C-MAC Video Stylet vs. Video Endoscope

Is a Rigid Fiberscope With a Flexible Tip Superior to Standard Flexible Fiberoptic Intubation: a Prospective Multicentre Randomised Controlled Trial

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03749837
Enrollment
18
Registered
2018-11-21
Start date
2018-12-15
Completion date
2024-07-31
Last updated
2025-06-06

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Intubation

Brief summary

The purpose of the study is to compare first attempt success rates and time until intubation to establish the learning curves of the participating anaesthesiologists with two different intubation strategies: (Karl Storz C-MAC VS (Video Stylet) and the standard flexible intubation video endoscope at the study site.

Detailed description

The intubation of the trachea is a crucial procedure in anaesthesia and emergency medicine, therefore it is considered as one of the core competences in these disciplines. Novices in the field need to learn intubation fast and without harming patients to ensure a patent airway if needed. According to the European Union of Medical Specialists (U.E.M.S., 1050 Brussels, BE), every anaesthesiologist has to master different techniques for the airway management. One is the fiberoptic intubation in awake or asleep patients, to manage a difficult airway. For further training, these core competences need to be extended during the career, from level A (has knowledge) to level D (teaches or supervises others). As the intubation with flexible fiberoptic scopes is the gold standard for the management of a known difficult airway, the investigators want to compare this to a new technique. The use of flexible scopes do not guarantee easy intubation in every difficult airway situation and intubation sometimes is difficult to achieve and requires high proficiency (unability to steer, unability to overcome an anatomical obstacle). Various approaches were introduced by the medical device industry to overcome that problem. One new device is a rigid video stylet with a flexible tip (Karl Storz C-MAC VS), which is an advancement of the older rigid scope Bonfils (Karl Storz). Intubation training with the Bonfils stylet has been shown to require about 20 consecutive tracheal intubations by novices to reach expert time. Learning curves for fiberoptic intubations seem to be similar, but a greater variance was observed. A study of the investigators research-group (unpublished data, KEK 247/09), comparing learning curves between the rigid fiberoptic Bonfils and the semi-rigid fiberoptic SensaScope suggested a 90% success rate for intubation within 60 seconds after about 15 trials (Bonfils) and 20 trials (SensaScope). In comparison, there is no validated data for the use of rigid scopes with flexible tips, as these tool are very new. Video stylets are tools originally designed for difficult airway management as well. The C-MAC VS combines rigid and semi-rigid abilities. Intubation seems to become very easy. But yet, there is no data available which proves that assumption. Thus the study wants to evaluate if intubation success and time is superior with the C-MAC Video Scope compared to the difficult intubation gold standard, the intubation with a standard flexible fiberoptic scope.

Interventions

DEVICEC- MAC VS

The C-MAC VS is a new device on the airway management aid market. It will be used according to the instructions of the distributor. Before the study starts on humans, each study participants will do at least 5 intubations on an airway manikin or more until he or she feels confident to use the device.

DEVICEVideo Endoscope

Fiberoptic video endoscopic devices are standard aids to facilitate intubation on all study sites and are used according to the instructions to use. To facilitate fiberoptic intubation a macintosh blade to raise the root of tongue will be used. Also with these devices the study participants need at least 5 trials to intubate a manikin (or more to feel confident) before they are going to use the study device in patients.

Sponsors

Insel Gruppe AG, University Hospital Bern
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
OTHER
Masking
NONE

Eligibility

Sex/Gender
ALL
Healthy volunteers
Yes

Inclusion criteria

* Anaesthesiologists starting in the respective anaesthesia department who are not experienced with tracheal intubation with the study devices * Informed Consent as documented by signature (Appendix Informed Consent Form) * Novice to the C-MAC VS * No/few fiberoptic oral asleep intubation experience (max. 5x during the last year)

Exclusion criteria

* More than 5 uses during the past year of either one of the study devices * Not available at the study site during entire study (expected drop outs) * Not able to fill out English case reports * Patients: Planned delayed extubation (e.g. planned transfer to ICU)

Design outcomes

Primary

MeasureTime frameDescription
Time (seconds) to successful orotracheal intubation during the first successful attempt.Start: Device passes patients lips; End: Device is completely removed out of the tracheal tube (a trial consists of a maximum of 2 intubation attempts, each with a maximum duration of 120 seconds)With the C-MAC VS and the standard flexible scope

Secondary

MeasureTime frameDescription
Patients demographic data such as ageDuring the process of screening, up to 24 hours before the study session startsThe age of each patient will be presented in years.
Patients demographic data such as genderDuring the process of screening, up to 24 hours before the study session startsThe gender of each patient will be presented in female or male.
Patients demographic data such as ASA risc classification (ASA= American Society of Anaesthesiologists)During the process of screening, up to 24 hours before the study session startsThe ASA grading system is used to evaluate the degree of a patient's physical state before selecting the anesthetic or before performing surgery.
Overall time from startpoint to glottic viewIt cannot be longer than 240 seconds and is defined for unsuccessful trials, i.e. if no intubation was established, as 360 seconds.The overall time is defined as the total time to glottic view, summarized over all attempts.
Time to first end expiratory CO2 readingStart: Device passes patients lips; End: First end expiratory CO2 reading (trial in total not >240 seconds)After the airway is secured the first end expiratory CO2 is shown.The investigators will use the standard non-invasive monitoring of the University Hospital to measure the end expiratory CO2
Number of intubation attemptsStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)End of an attempt defined as: device has to be completely removed out of the patient's airway.
Subjective difficulty of the intubation procedureStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 secondsThe VAS- Visual analogue scale (score 1-10) is used. It is a measurement instrument for subjective characteristics that cannot be directly measured. Therefore numbers are used to evaluate.
Cormack/Lehane gradeStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The Cormack/Lehane grade is used to describe the laryngeal view during laryngoscopy. It is rated by the supervisor.
Patients demographic data such as heightDuring the process of screening, up to 24 hours before the study session startsThe size of each patient will be presented in meter/centimeter
Patients demographic data such as weightDuring the process of screening, up to 24 hours before the study session startsThe weight of each patient will be presented in kilograms
Limited or restricted vision through the devices (either C MAC VS or a standard flexible scope)Start: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The view can be clear or blurred.
Correlation to patients' anatomical characteristicsStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)To assess the influence of difficulty with the airway
Patients vital parameter such as heart rate, during the intubation attemptStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The investigators will use the standard non-invasive monitoring of the University Hospital to measure the heart rate.
Patients vital parameter such as blood pressure, during the intubation attemptStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The investigators will use the standard non-invasive monitoring of the University Hospital to measure the blood pressure (in millimeters of mercury)
Patients vital parameter such as oxygen saturation, during the intubation attemptStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The investigators will use the standard non-invasive monitoring of the University Hospital to measure the oxygen saturation (SpO2 in percent).
Participants characteristics and demographic dataBefore the study session starts (up to 24 hours before the first intubation attempt)Basic demographic data (including years of experience in anaesthesia).

Other

MeasureTime frameDescription
Incidence of injuries due to intubation attemptsFollow-Up on the first post anaesthesia day (maximum 24 hours post anaesthesia)Dental damage, mucosal damage, hoarseness, sore throat, swallowing disorders
How often a hand over to specialist happensStart: Device passes patients lips; End: Device is completely removed out of the tracheal tube (trial in total not >240 seconds)The device has to be handed over to the supervisor

Countries

Canada, Spain, Switzerland

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026