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

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

Video: think about setup and technique Video deleted due to size http://www.youtube.com/watch?v=Y-jWvT0fPSg Video (start at 00:37)

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

1. Predict trouble?

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

LEMON (difficult DL) Look (gestalt) Evaluate 3-3-2 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

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

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

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

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?

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

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%

-- 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: 1054-7). **High flow NC O2 increases safe apnea time (variable, depending on pt population)

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

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?

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%

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

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

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!!

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

Using a Bougie http://www.youtube.com/watch?v=qcDXZgV3m8I Using pocket bougie with VL: http://prehospitalmed.com/2012/08/24/ducanto-wields-glidescope-and-pocket-bougie/

Video deleted due to size (Start at 20 sec)

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.

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

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

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

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

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

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

King LT Video deleted due to size

Laryngeal Mask Airway (LMA) Video deleted due to size

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

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?

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…

Specific Learning Objectives (20 min) (try) to predict difficult airways: Gestalt, LEMON 2. Optimize intubating conditions for (all) airways a. Monitoring Stop attempts @ 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

Questions?