Transcript No Slide Title

Five New Devices for the Difficult
Airway
Ron M. Walls, MD
Brigham and Women’s Hospital
Harvard Medical School
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
A Haiku
Can’t intubate, can’t
ventilate…Panic. Flail. Brain Cells
die in bunches.
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Outline
• Magnitude of the problem
• Where do new devices fit in?
• New devices
The Difficult Airway
© 2009 Ron M. Walls, MD
Difficult Laryngoscopy:
Cormack-Lehane Score
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Magnitude of the Problem: OR
• Grade 3 or 4 laryngoscopy < 5%
• True grade 4 laryngoscopy < 1%
• Impossible intubation 0.35% of
“normals”
• “CICV” ~ 1:10,000 or 0.01%
• Patients are “pre-selected”
• NOT applicable to ED or out-of-hospital
intubations
Cormack, Karkouti, Langeron, Mallampati, Samsoon, Williams, Wilson, others
The Difficult Airway
© 2009 Ron M. Walls, MD
How common is difficult
bag mask ventilation?
• In the OR (patients are pre-selected)
– Difficult BMV in 1.5 - 5%
– Impossible BMV in 0.16%
– Difficult BMV with difficult intubation in ~ 0.3% to
5%
– Difficult BMV makes DI 4x more common, and
impossible intubation 12x
• Numbers not known for the ED, EMS
Langeron O et al. Anesthesiology 2000 May 92 1229-1236.
Kheterpal S et al. Anesthesiology 2006 Nov; 105:885-91.
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Outline
• Magnitude of the problem
• Where do new devices fit in?
• New devices
The Difficult Airway
© 2009 Ron M. Walls, MD
Where do new devices fit in?
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Historically considered novelties, “toys”
Reserved for difficult, failed airways
Late adopters vs early adopters
The real question is…
The Difficult Airway
© 2009 Ron M. Walls, MD
Where do new devices fit in?
If you had trained on, and used, a video
laryngoscope, or a fiberoptic stylet, and
DL was newly introduced:
• What would the studies show?
• Would you adopt the new technology?
• Would the lower cost matter?
The Difficult Airway
© 2009 Ron M. Walls, MD
Where do new devices fit in?
If you had trained on, and used, a video
laryngoscope, or a fiberoptic stylet, and
DL was newly introduced:
• The studies? Clear inferiority!
• Would you adopt? No!
• Would the lower cost matter? No!
The Difficult Airway
© 2009 Ron M. Walls, MD
Where do new devices fit in?
• These are “every intubation” devices
• There is a learning curve
• The question is not whether, but which,
and when?
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Outline
• Magnitude of the problem
• Where do new devices fit in?
• New devices
The Difficult Airway
© 2009 Ron M. Walls, MD
The future of difficult
laryngoscopy?
• All difficult laryngoscopy definitions are
based on direct laryngoscopy
• Most have to do with impossibility of creating
“a line of sight”
• Video laryngoscopes will require an entirely
new way of thinking
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Glidescope
• Video laryngoscope
• Minimal mouth opening required
• Very high intubation success rate
• Allows “teacher” to share view with “student”
• Portable, durable
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Glidescope
The Difficult Airway
© 2009 Ron M. Walls, MD
How good is
the Glidescope?
The Difficult Airway
© 2009 Ron M. Walls, MD
Is there a learning curve?
• 728 patients, 133 operators, 18 months
• 133/728 had DL and GVL – GVL always
equal or better view
• 35 with grade III/IV with DL; 24/35 better
with GVL
• Failure 26/728 (3.6%), 14/26 had grade I
views
Cooper RM: Can J Anaesth 52:191, 2005.
The Difficult Airway
© 2009 Ron M. Walls, MD
For Routine Airways ?
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DL then GL on 400 elective anesth patients
DL: 67%, 26%, 6%, 0.5% grades I-IV
GL: 89.5%, 10.5%, 0%, 0%
Success GL: 85.5%, 97.5%, 99.9% att 1-3
All <40 secs, mean 21 secs
1/400 not intubated despite Grade I view
Tremblay M-H et al. Anesth Analg 2008 May; 106:1495.
The Difficult Airway
© 2009 Ron M. Walls, MD
For Novices ?
• 20 novice clinicians (paramedic students,
PGY1 residents, nurses, med students)
• Demo then 3 successful intubations with DL
and GVL on manikins
• 200 patients (5+5 each)
• 93% vs 51% success in <120 secs
• CL III/IV 8% vs 50%.
• Time 63 secs vs 89 secs
Nouruzi-Sedeh P: Anesthesiology 110:32, 2009
The Difficult Airway
© 2009 Ron M. Walls, MD
For C-Spine Injury ?
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20 elective anesth patients with ILS
2 anesth residents with 30x experience
Continuous fluoro
CSpine movement comparable
Grade 1: 50% v 0%, 2: 50% v 65%, 3: 0% v 35%
Robitaille A: Anesth Analg 106:935, 2008.
The Difficult Airway
© 2009 Ron M. Walls, MD
Is there a learning curve?
• 728 patients, 133 operators, 18 months
• 133/728 had DL and GVL – GVL always
equal or better view
• 35 with grade III/IV with DL; 24/35 better
with GVL
• Failure 26/728 (3.6%), 14/26 had grade I
views
Cooper RM: Can J Anaesth 52:191, 2005.
The Difficult Airway
© 2009 Ron M. Walls, MD
McGrath Videolaryngoscope
• Videoscope with built in
screen
• Blade design similar to GS
• Plastic sheath for blade
• Blade adjustable
The Difficult Airway
© 2009 Ron M. Walls, MD
McGrath in Clinical Studies
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Mostly case series and reports
143/150 patients Grade I, 6 Grade 2
98% intubation success
No comparison studies (yet)
Shippey B: British Journal of Anaesthesia 2008 100(1):116-119
Shippey B: Can J Anaesth 2007; 54:307-313.
The Difficult Airway
© 2009 Ron M. Walls, MD
Storz Video Laryngoscope
• Video/FO laryngoscope
• Based on standard blades
• Interchangeable video camera system
• Pediatric and adult blades
• High quality optics
The Difficult Airway
© 2009 Ron M. Walls, MD
Storz CMAC®
(now released)
The Difficult Airway
© 2009 Ron M. Walls, MD
CMAC vs Storz VL
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Storz VL is fiberoptic coupled to CCD video
CMAC is “pure” CMOS video
Fogging vs no fogging
Two cables vs one
Expense
Complexity
Image quality
The Difficult Airway
© 2009 Ron M. Walls, MD
How good is
the Storz VL?
• 54 patients have DL and SVL by exp anesth
• 7x greater force on maxillary incisers DL vs
SVL
• 17% grade III/IV vs 0%
Lee RA: Anesth Analg 108:187, 2009.
The Difficult Airway
© 2009 Ron M. Walls, MD
For learning ?
• 49 novice intubators on manikins with
normal or Diff Airways, DL vs SVL
• 84% vs 54% first attempt success
• Less dental trauma
• Greater confidence, considered intubation
less difficult than DL group
Low D: Anaesthesia 63:195, 2008
The Difficult Airway
© 2009 Ron M. Walls, MD
Pentax AWS®
(not yet released in the US)
• Videoscope with preload
tube channel
• Lenticle helps aim
• Light, portable
The Difficult Airway
© 2009 Ron M. Walls, MD
How good is
the Pentax AWS?
• Better view, less CS movement than MAC
• 46/320 patients grade III/IV with MAC:
– 45 Grade I, 1 Grade IIa with AWS
– IDS with AWS 0 in 305, 1 in 14, 2 in 1
• Decreased CS movement with bougie
Enomoto Y: British Journal of Anaesthesia 2008 100(4):544-548
Suzuki A: Anaesthesia. 63(6):641-647, June 2008.
Takenaka I: Anesthesiology 110:1335-40, June 2009.
The Difficult Airway
© 2009 Ron M. Walls, MD
Fiberoptic Stylets
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Storz Bonfils®
Clarus Shikani Optical Stylet®
Clarus Levitan® Stylet
AirRIFL®
All (except Levitan) avoid DL
Rigid, + malleable
Like lighted stylet, but “visual”
Portable, have own light source
The Difficult Airway
© 2009 Ron M. Walls, MD
SOS
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Malleable FO
Midline approach
Inexpensive
Video adaptable
The Difficult Airway
© 2009 Ron M. Walls, MD
SOS
• 55% less C-Spine movement than MAC DL
• 28 vs 17 seconds to intubate
• Better and faster than DL + bougie in
manikin model
• Case reports, small series in children
Turkstra TP et al. Can J Anesth 54:441; 2007.
Evans A et al: Anaesthesia 61:478; 2006.
The Difficult Airway
© 2009 Ron M. Walls, MD
Air RIFL®
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New dynamically adjustable FO stylet
Little/no research data
No real clinical experience (yet)
Cool entrepreneurial website, though
The Difficult Airway
© 2009 Ron M. Walls, MD
Bonfils Stylet
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Non-malleable
Retro-molar approach
Popular in N Europe
Self contained
High quality optics
Higher price than SOS
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
AirTraq®
• “Periscope”
• Mounted tube
• Disposable
Maharaj CH et al., Anesthesiology 2007 Jul; 107:53-9.
Maharaj CH et al., Anaesthesia 2008 Feb; 63:182.
Hirabayashi Y et al., Anaesthesia 2008 Jun; 63:635.
The Difficult Airway
© 2009 Ron M. Walls, MD
Take home points?
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VL is superior to DL
Shorter learning curve
Better glottic views
Equal or better on virtually every measure
So, what is holding us back?
The Difficult Airway
© 2009 Ron M. Walls, MD
The Difficult Airway
© 2009 Ron M. Walls, MD
And the Venerable Laryngoscope?
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Prediction
By 2010, a minority of
ED intubations will be done
using a conventional
laryngoscope and blade.
www.theairwaysite.com
The Difficult Airway
© 2009 Ron M. Walls, MD
New Devices for the Difficult Airway
Another Haiku
Can’t intubate. Can’t
ventilate. Knew in advance.
Plan rescues the life.
www.theairwaysite.com
The Difficult Airway
© 2009 Ron M. Walls, MD
The Difficult Airway
FIN
The Difficult Airway
© 2009 Ron M. Walls, MD