1. Difficult Airway Fundamentals
Brandon Wills, DO, FACEP, FACMT
Department of Emergency Medicine
VCU Medical Center
Virginia Poison Center

2. Do you ever really know when you’ll have a difficult airway???

3. Video: think about setup and technique
Video deleted due to size
Video (start at 00:37)

4. Specific Learning Objectives (20 min)
1. (try) to predict difficult airways
2. Optimize intubating conditions for (all) airways
a. Monitoring
b. Oxygenation
c. Positioning
d. BVM technique
e. DL technique + bimanual
f. VL/ Tube delivery nuggets
3. Adjuncts if things aren’t working

6. 1. Predict trouble?

7. 1. Predict trouble? Who will be “difficult”? Gestalt/ knowledge
LEMON (difficult DL)
MOANS (difficult BVM)
RODS (difficult EGD)
SMART (difficult Cric)

8. LEMON (difficult DL)
Look (gestalt) Evaluate Mallampati Obese/ obstruction? Neck mobility (trauma)
Mallampati I -can see everything
Mallampati II- uvula fully visible
Mallampati III- can’t see tip of uvula
Mallampati IV- can only see soft palate
Reminder from cadaver lab- some did not have overt signs of being a difficult airway but were impossible to DL
None are perfect: small mouth, short neck, short jaw, trauma, obese all make it harder

9. MOANS (difficult BVM) Mask seal Obstruction Aged (> 55) No teeth
Stiff lungs
(asthma, COPD, ALI, pregnancy)

10. RODS (difficult EGD)
Restricted mouth opening Obstruction/ obese Distorted airway Stiff lungs

11. SMART (difficult cric)
Surgery Mass Access/ anatomy Radiation Tumor

12. You are concerned… But decide RSI is reasonable
30 year old male
Drug overdose
Needs airway protection
You are concerned… But decide RSI is reasonable
How do you optimize his intubation from start to finish?

13. Oxygenation buys you time!!!!
Time for additional attempts
Time for adjuncts/ EGD’s
Time for additional help
Can’t oxygenate? failed airway algorithm
GOAL: Avoid critical hypoxia= 70% SpO2
Optimize: Oxygenation & ↑ first pass success

14. 2. Optimize intubating conditions for (all) airways. a. Monitoring
2. Optimize intubating conditions for (all) airways a. Monitoring know your pulse oximeter
100%
90%
As the patients SaO2 starts to drop the SpO2 remains high due to “averaging” of saturation values over time. This creates a lag between what the patient is experiencing and what the monitor shows. As saturations are actively falling, a SpO2 of 90% actually represents a sub-90% saturation. Conversely, as you begin to bag the patient, there will be a lag or delay until the sats start to improve. I don’t know how long the “monitor lag” is though…
Monitor SpO2
Actual patient PaO2
Take-home nugget: Start oral airway + BVM at SpO2 of 92%

15. -- NRM + NC apneic oxygenation +/- NIPPV
2. Optimize intubating conditions for (all) airways b. Oxygenation
-- NRM + NC apneic oxygenation +/- NIPPV
Nuggets:
3 min on high-flow O2
8 vital capacity breaths
Apneic oxygenation
NIPPV if needed
**SpO2 of 90% puts you right on the edge of the dissociation curve; small changes in SpO2 may have large changes in PaO2
**Pt bed up 20 degrees= 100 extra seconds of additional safe apnea time in obese patients (Lane S, et. al. Anaesthesia 2005; 60: ).
**High flow NC O2 increases safe apnea time (variable, depending on pt population)

16. 2. Optimize intubating conditions for (all) airways b. Oxygenation
Scott D. Weingart, Richard M. Levitan, MD
Ann Emerg Med, 2011

17. 2. Optimize intubating conditions for (all) airways c. Positioning
“Ear-to-sternal notch”
Positioning improves:
Oxygenation
Reduces regurgitation
Improves view during DL/VL by optimizing oral, pharyngeal, and laryngeal axes
Where should the ear be?

18. 2. Optimize intubating conditions for (all) airways d. BVM Technique?
Take-home nuggets:
Two-hand thenar technique
ALWAYS use oral & NP airway
No cricoid pressure
No BVM if SpO2 > 95%

19. 2. Optimize intubating conditions for (all) airways e. DL Technique
Low Grip, thumb up
Elbow in
Slight tongue sweep, STAY MIDLINE
Slow midline advance look for epiglottis
Seat in vallecula
Gentle lift forward
Bimanual if needed to tweak things
Epiglottis= THE reliable anterior landmark
Beware: epiglottis camouflage= epiglottis can sit in post pharynx in pooled secretions; may need to lift out or suction
Seat in vallecula to put pressure on the hyoepiglottic ligament

20. 2. Optimize intubating conditions for (all) airways e. DL Technique
Video deleted due to size
Epiglottis= THE reliable anterior landmark
Beware: epiglottis camouflage= epiglottis can sit in post pharynx in pooled secretions; may need to lift out or suction
Seat in vallecula to put pressure on the hyoepiglottic ligament
Nuggets:
Epiglotoscopy
Bimanual laryngoscopy

21. 2. Optimize intubating conditions for (all) airways e. DL Technique:
Why bimanual laryngoscopy?
Cormack & Lehane Grades
B-U-R-P or BML improves the C-L view by one full grade!!

22. 2. Optimize intubating conditions for (all) airways e. DL Technique:
When to use a Bougie??
Grade III success improved from 66% to 96%
Advance to about 25cm at the teeth
Must continue laryngoscopy while tube is being placed
70cm bougies probably better than the 60cm variety

23. Using a Bougie http://www.youtube.com/watch?v=qcDXZgV3m8I
Using pocket bougie with VL:

24. Video deleted due to size
(Start at 20 sec)

25. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
99% C-L Grade I or II view (but only 96% success  Why??)
Glidescope VL
Possibly better for more anterior airways
C-MAC
Can perform DL
Can can use Bougie!!
No special stylet needed
-In a series of c-spine immobilized pts, GVL improved CL view by one grade (Agro, 2003)
-A series of 728 intubated, 99% had C-L 1 or 2 views (Cooper, 2005)
Other tips:
I don’t tell students to get the blade tip in the vallecula like with DL, it just makes VL harder because then end up pulling the larynx too anterior which just compounds the problems of passing the tube.  As you and I both know seeing the cords isn’t the problem, getting the tube in is.  When students in their excitement of seeing that grade I view (often for the very first time!!) love to keep this view at the expense of making getting the tube in very difficult.
What I teach is a grade II view is all you need and is actually what you want.  Once you get this, similar to inserting the blade you insert the tube with the long axis pointing to 3 o’clock and watch the tip go into the mouth and past the back of the tongue.  Now look at the screen and keep advancing slowly.  Once you can see a hint of plastic on the screen, rotate the tube to 12 o’clock and presto, the tube tip is right at the cords.

26. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
Levitan Airway course

27. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
Video deleted due to size
VL blade too deep, structures too close, tube passage impossible

28. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
Delivery during DL
Delivery during VL
Glidescope
Straight tube, 30 degree bend at tip
Levitan, Ann Emerg Med, 2010

29. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
Stylet “Straight to Cuff”
Straight tube, 30 degree bend at tip
Levitan, Ann Emerg Med, 2010

30. 2. Optimize intubating conditions for (all) airways. e
2. Optimize intubating conditions for (all) airways e. VL + Tube Delivery
Come up to target from
below line of sight
If hung up:
rotate right + remove stylet
Levitan Airway course

31. Grade IV view or can’t intubate
Options?
BVM + OPA/NPA Another attempt with different technique
(e.g. VL + bimanual +/- bougie)
BVM + OPA/NPA Attempt EGD

32. King LT
Video deleted due to size

33. Laryngeal Mask Airway (LMA)
Video deleted due to size

34. Can’t intubate + failed ventilation
Options?
Attempt EGD or
EGD as bridge to cricothyrotomy

35. You are concerned… But decide RSI is reasonable
30 year old male
Drug overdose
Needs airway protection
You are concerned… But decide RSI is reasonable
What would be your approach to his intubation from start to finish?

36. Patient RSI Setup Position?
Preoxygenate?
Intubating method?
Backup #1?
Backup #2?
30o head up + ramp + ear to notch, face to ceiling
Oxygenate with high-flow NRM + Apneic oxygenation using 15L NC O2
Primary method: DL/VL + Bimanual
Bougie for C-L Grade III view
LMA or iLMA
There is no “right answer” for your backups; this will depend on the gadgets you have at your institution, resources, and backup…

37. Specific Learning Objectives (20 min)
(try) to predict difficult airways: Gestalt, LEMON
2. Optimize intubating conditions for (all) airways
a. Monitoring Stop SpO2 of 90-92%
b. O2 Always pre-O2 + apneic O2
c. Positioning Earsternal notch, face to ceiling, +/- ramp
d. BVM technique Two-hand thenar with OPA/NPA
e. DL technique Epiglotoscopy laryngoscopy + bimanual
f. VL/ Tube delivery nuggets Don’t get too close, up to line of sight
3. Adjuncts if things aren’t working- bougie, EGD

38. Questions?