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To reference this electronic educational resource according to the APA style for Web references, use:
Gravenstein D, Lampotang S (2006): AirTraq Laryngoscope. Retrieved <insert date of retrieval here>, from University of Florida Department of Anesthesiology, Center for Simulation, Advanced Learning and Technology, Virtual Anesthesia Machine Web site: http://vam.anest.ufl.edu/airwaydevice/airtraq/index.html
Keywords: AirTraq, Intubation, difficult airway, airway management,
video-intubation
AIRTRAQ®
See AIRTRAQ videos in the video library
Introduction
The AIRTRAQ single-use optical laryngoscope is designed to provide a view of
the glottic opening without aligning the oral, pharyngeal, and laryngeal axes.
Compared to conventional direct laryngoscopy, rigid video laryngoscopes require
minimal head manipulation and positioning. The AIRTRAQ requires a minimal mouth
opening of 18 mm for the regular size and 16 mm for the small size AIRTRAQ.
The blade of the AIRTRAQ has one channel acting as the housing for
the placement and insertion of the endotracheal tube (ETT) while
another channel terminates in a distal lens. A battery operated low
temperature LED light at the tip of the blade provides illumination
for up to 90 minutes. The image is transmitted to a proximal viewfinder
through a combination of lenses and a prism, rather than fiber optics,
allowing visualization of the glottis and surrounding structures,
and the tip of the tracheal tube. An anti-fogging system for the optics is activated
by turning on the LED light. For the anti-fogging system to be effective, the
LED must be turned on at least 30 seconds before use.
According to the manufacturer,
the AIRTRAQ works with any style endotracheal tube: standard, reinforced (wired)
and pre-shaped (RAE). Endotracheal tubes of inner diameter (ID) sizes
7.0 mm through 8.5 mm can be used with the regular size and 6.0 to 7.5 mm for
the small size AIRTRAQ (16 mm minimum mouth opening). An optional color video
camera clips onto the proximal viewfinder and transmits to a display (such as
a TV) via a lightweight cable. Display on a monitor viewable by more than
one person at a time is useful for teaching purposes.
Use of the recently introduced AIRTRAQ has been described for oral intubations
in intubation manikins (Maharaj et al 2006) with no publications related to studies
with patients. Intended uses suggested by the manufacturer include ETT
placement, ETT exchange, placement of other devices, e.g., gastric tubes. There
are two (2) AIRTRAQ sizes available - Regular and Small.
These features likely make the AIRTRAQ a good option for scenarios where conventional
direct laryngoscopy might prove to be difficult or dangerous: patients with anterior
larynx, unstable cervical spine fracture, patients in the sitting position, upper
body burns, trauma, TMJ immobility, and micrognathia.
Compared to the MacIntosh laryngoscope in simulated easy laryngoscopy scenarios,
there was no difference between the AIRTRAQ and the MacIntosh in success of tracheal
intubation. “The time taken to intubate at the end of the protocol was
significantly lower using the AIRTRAQ (9.5 (6.7) vs. 14.2 (7.4) s), demonstrating
a rapid acquisition of skills. In the simulated difficult laryngoscopy scenarios,
the AIRTRAQ was more successful in achieving tracheal intubation, required less
time to intubate successfully, caused less dental trauma, and was considered
by the anaesthetists to be easier to use”. (Maharaj et al 2006). These
findings are consistent with the reports of the clinical performance of other
rigid optical laryngoscopes and our own experience (unpublished) using the AIRTRAQ.
Preparation
We will describe the preparation and sequence of events when using
the AIRTRAQ for oral intubation in a patient induced with general anesthesia.
Ideally, the AIRTRAQ is prepared before use: the LED light turned on
for 30 s or longer, the proper sized ETT has the cuff deflated and
is lubricated and loaded into the channel. The view through the eye-piece
or displayed from the camera is checked to assure the view is not obstructed
by the ETT being advanced too far down the channel. The tip of the
AIRTRAQ is also lubricated. Following induction of anesthesia, the
AIRTRAQ blade is inserted into the mouth in the midline and passed
over the center of the tongue. To help with insertion, one can use
a finger to open the mouth. Some anatomy (e.g. short jaw and
neck with a large chest) may not allow easy AIRTRAQ insertion in this
manner and may require insertion laterally to the tongue; or slightly
oblique; or with more neck extension
or using a retromolar approach. Advancing the AIRTRAQ while applying some distraction
on the blade will usually allow the intubationist to identify the uvula and then
the epiglottis as the blade is advanced. Typically, the tip will come to be positioned
in the vallecula where upon the epiglottis is lifted by elevating the blade.
The tracheal tube is then advanced down the channel while maintaining the vertical
lifting force that keeps exposing the vocal cords and the ETT cuff
can be observed passing through the vocal cords. Once the cuff has
passed the vocal cords, one can inflate the cuff, connect the breathing
circuit, and then separate the ETT from the guiding channel by using
a peeling method, most easily by placing a finger between the channel
and ETT and pushing it down the length of the channel until the ETT
fully separates from the channel. The AIRTRAQ is then removed while
holding the ETT in place.
Oral Intubation: A Step by Step Guide
- Induce patient as if for regular intubation; apply cricoid pressure if rapid sequence intubation is desired.
- Patient position should be undisturbed or neutral, not "sniffing". Some authors even propose a slight flexion of the head and neck to increase the chance of the scope picking up the epiglottis. One can start the patient in the sniffing position as well.
- Position yourself as for regular direct laryngoscopy and position the scope axis parallel to patient axis pointing caudad (see the animation in the Bullard laryngoscopy section, or view the videos of actual AIRTRAQ uses.)
- Introduce the scope tip between the teeth, into the pharynx. Try to stay as close to midline as possible.
- Advance the AIRTRAQ/ETT assembly over the tongue, sweep to a position perpendicular to the patient axis minimally distorting the anatomy. The aim is to introduce the tip into the vallecula and then elevate the epiglottis by suspending it. The tip can also be placed under the epiglottis, Miller style, as an alternative.
- Elevate the AIRTRAQ handle straight up. The blade tip should retract the epiglottis and you should be able to visualize the glottic opening. It should be noted that this is NOT a passive technique where the scope is simply advanced into the pharynx for visualization. SUSPENSION laryngoscopy is required to establish the viewing space necessary to identify the epiglottis and ultimately the larynx. When performing suspension laryngoscopy, the right hand can be placed on the laryngoscope for stabilization. Alternatively, some prefer to use the right hand to grab the mandible (thumb in the mouth, fingers on mentum) and elevate it so that less traction can be applied to the AIRTRAQ laryngoscope, thereby making maneuverability easier.
Troubleshooting Tips
Cannot see vocal cords
Usually this means one is not exactly midline or one is in too far
(deep). First, withdraw the AIRTRAQ slightly and lift up. Also
because the view through the AIRTRAQ is less panoramic than during
regular intubation, it is harder to correct during laryngoscopy if
you are not entering the mouth perfectly in the midline. Step back
and determine if you are perfectly midline with the laryngoscope. Feel
the trachea or thyroid cartilage to determine the midline again, then
re-advance the laryngoscope. Another approach to the above problem
would be to elevate the jaw with the right hand while looking through
the eyepiece at the same time. Then attempt to visualize the vocal
cords, the decreased amount of pressure on the blade will make it easier
to maneuver the blade.
Difficulty advancing the ETT with the vocal cords visualized
The main difficulty in advancing the ETT might be one of several situations: vocal
cords are not in the middle of the view, inadequate lubrication, failure
to use an ETT of recommended size or failure to fully deflate the ETT
cuff.
Difficulty advancing the ETT between visualized vocal cords
The design of the AIRTRAQ is such that the tip of the ETT enters the
visual field from inferior and to the right of the visual field by
the tube guiding channel of the AIRTRAQ. When the ETT continually advances
too posteriorly and/or too far right of the vocal cords, several maneuvers
should be considered:
- Attempt to withdraw the entire AIRTRAQ slightly so it is not as close to the vocal cords, lift upwards and try again. By withdrawing slightly, the ETT has additional distance to travel more medial and the curve of the ETT to bring the tip anteriorly.
- One might also consider using a pencil-tip ETT (e.g. Parker Tube, Parker Medical) that does not have an unfavorable bevel angle and “self-directs” towards midline.
Fogging of view
The AIRTRAQ incorporates a heater which heats
up the distal lens to prevent fogging. The AIRTRAQ video library includes
a case when the light (and thus the heater) was turned on too late and insufficiently
ahead (>= 30 s) of intubation.
Web authors: D. Gravenstein, S. Lampotang
- Maharaj, C. H., Costello, J. F., Higgins, B. D., Harte, B. H. & Laffey, J. G: Retention of tracheal intubation skills by novice personnel: a comparison of the Airtraq and Macintosh laryngoscopes. Anaesthesia. Mar;62(3):272-8, 2007
- Dhonneur, G, Ndoko, S, Amathieu, R, el Housseini, L, Poncelet, C, Tual, L: Tracheal Intubation Using the Airtraq in Morbid Obese Patients Undergoing Emergency Cesarean Delivery, Anesthesiology 106:629–30, 2007
- Mort TC: Laryngoscopy
vs. Optical Stylet vs. Optical Laryngoscope (Airtraq) for Extubation
Evaluation, Anesthesiology, 105:A823, 2006
- Maharaj, C. H., Costello, J. F., Higgins, B. D., Harte, B. H. & Laffey, J. G: Learning and performance of tracheal intubation by novice personnel: a comparison of the Airtraq® and Macintosh laryngoscope. Anaesthesia. Jul;61(7):671-7, 2006