The Emergency Airway
National Review Course in Emergency
Medicine
Kirk Magee MD, MSc, FRCPC
Associate Professor
Dalhousie Department of Emergency
Medicine
Conflict of Interest
• Fresenius Kabi
– European Society of Anaesthesiology
Symposium, Stockholm, Sweden, 2014
• “Propofol in ED PSA”
Outline:
• Recognition: is this an airway question?
• Cases
Case
• A 35 year old female presents to the ED
with an altered LOC. She was found
surrounded by empty pill bottles
• Vital Signs: HR 130, BP 115/78, sats 98%,
GCS 6/15
• Is this an airway question?
Types of Airway questions
• Recognition of the need for an airway
• Description of RSI and recognition of
relative contraindications
• Recognition and management of a difficult
airway
• Post intubation management
• Approach to the failed airway
How to drive an examiner nuts…
• “I would perform an RSI with a double
set-up”
Questions you need to consider:
• Does this patient need an airway?
• Any predictors of difficulty?
• Right time, right place, right person?
• What drugs will you use?
• How will you deal with complications?
Exam triggers to the difficult
airway:
• Morbidly obese
• Trauma to head or neck
• Burns
• Stridor
• Prior unsuccessful attempts
• Asthma
• Anaphylaxis
Beware…
BMV
Laryngoscopy
Difficult Mask Ventilation
‘BOOTS’
• Beard
mask seal issues
• Obese
• Older
lung/chest wall
compliance
head/neck position
• Toothless
mask seal
• Snores/Stridor
obstruction
Predicting Difficult Laryngoscopy and Intubation
MMAP the airway:
• Mallampati
and
Measure 3-3-1
• A-O extension
• Pathologic conditions
‘MMAP’
>
Lets get ready to rumble!
Cases
Case 1
• 34 yo asthmatic presents with severe
respiratory distress
• Normal airway
• VS: 122, 32, 156/90
Special Considerations
• Percipitating causes:
– Pneumothorax, mucous plug
– Role of epinephrine
• Difficult/impossible to BMV
• Permissive hypercapnea
• Ketamine
• Apneic oxygenation
“NO DESAT”
Nasal Oxygen During Efforts Securing A
Tube
Pre-oxygenation combining high
flow nasal canula and a nonrebreather mask
• Measured inspired oxygen NRBM @ 15 lpm only
60-70%
– Pt’s expired gasses are mixing with applied O2 in
nasopharynx
• High flow nasal O2 flushes the nasopharynx with
O2
– When pt inspires, inhale higher percentage of inspired
O2
• Small changes in FiO2 create dramatic changes in
the availability of O2 at the aveolus
Apneic Oxygenation
• Alveoli will continue to take up O2 even
without diaphragmatic movments
• Optimal circumstances: PaO2 can be
maintained at > 100 mmHg for up to 100
minutes without a single breathe!
“If you enter the exam as a
resident, that is how you will
leave, but if you enter as a
consultant…”
Be decisive!
Case 2
• 4 yo presents with a 3 day hx of fever and
“flu-like” symptoms
• Unable to arouse
• VS: 139, 32, 60/40
Special Considerations
• Not just “little adults”
The Pediatric Airway
•
•
•
•
•
•
•
•
•
Smaller airway
Large occiput
Tongue is larger
Larynx is relatively cephalad in position
Epiglottis is more floppy
< 10 yrs, narrowest portion of airway is below
vocal cords
Higher basal metabolic rate
bradycardia
PTJV surgical airway of choice for < 10 years
Percutaneous Transtracheal Jet
Ventilation (PTJV)
Important pediatric numbers:
• ET Tube size:
• ET Tube depth:
Age
+4
4
Age
2
+4
Breslow Tape
Case 3
• 26 yo Type 1 diabetic
• Florid DKA, not protecting his airway
• VS: 127, 28, 95/66, 95%
Special Considerations
• Hyperkalemia
• Post-intubation still need high respiratory
rate
– DKA
– ASA overdose
Contraindications to Sux
• Hyperkalemia
• Burns > 10% BSA
• Crush injury
• Denervation
• Neuromuscular disease
– ALS, MS
• Malignant hyperthemia
How about contraindications to
Rocuronium?
Case 4
• 50 yo pulled from burning car
• Significant burns to face, stridor
• VS: 112, 28, 132/88, 88%
Special Considerations
• Difficult airway
• Toxicology
– CO
– CN
MMAP: Pathological Obstructing
Conditions…
e.g. Periglottic edema
e.g. Glottic trauma
MMAP: Pathologically Obstructing
Conditions…
…with deep sedation
may be impossible to
BMV or intubate !!
Two Possible Scenarios
• Can’t Intubate
• Can Ventillate
• Can’t Intubate
• Can’t ventillate
What are your options?
• If not contraindicated, RSI may actually
improve success rate
– Double set-up
• Are you the right person, is the ED the
right location?
• Awake intubation
‘Awake’ intubation
…Intubation with topical airway anesthesia
and light sedation.
Advantages
Disadvantages
• Airway maintained
• Can be difficult
• Breathing continues • Cooperation
• Stable hemodynamics • Adverse reflexes
(GI/CNS/CVS)
The Failed Airway
Rescue Device: King Vision®
Rescue device: Glide Scope®
Rescue ventilation devices: LMA
www.lmana.com
Rescue ventilation devices: I-LMA
Rescue devices: Lighted Stylet
Rescue techniques
• Glide Scope®
• LMA
• I-LMA
• Lighted Stylet
• Esophagotracheal Combitube
• Retrograde Intubation
• Fiberoptic Intubation
Can’t ventilate, Can’t intubate
Cricothryotomy Contraindications:
• Distorted neck anatomy
• Pre-existing infection
• Coagulopathy
• +++ difficult in pts < 10 yrs of age
Relative Contraindications!
Decribe how you would
perform a cricothyrotomy
What equipment do you need?
• “Old School”
– Scalpel
– Tracheal dilator (Trousseau dilator) or
spreader
– Tracheal hook
– Portex or Shiley tube (No. 5-6 in adult)
• Melker Kit
• Bougie
Case 5
• 72 yo with altered LOC and urosepsis
• Normal airway
• VS: 124, 20, 70/40
Special Considerations
• CBA not ABC!
– Maximize BP first
• Relative contraindication for etomidate?
“If only I had been a vet…”
Case 6
• 26 yo mountain biker “clothes-lined” on
wire fence at high speed
• Pt is unable to talk; obvious respiratory
distress
• Edema and echymosis evident at his neck
• VS: 115, 26, 160/85, 88%
Special Considerations
• The “most difficult” airway!
• Patent airway may be lost with deep
sedation/paralysis
• How does the scenario change with:
– Time from injury
– Community vs Urban ED
– “stable” vs. “unstable”
Your 1st attempt should not be in
Ottawa at the exam centre!
Putting it all together
• Preparation – predictors of difficult
BMV/laryngoscopy
• Preoxygenate – no BMV
• Paralysis and induction agent
• Placement of tube and confirmation
• Post tube management
Putting it all together…
Assess predictors of
difficult BMV/laryngoscopy
Pre-oxygenate
Confirm Tube
Placement
Paralytic/Induction Agent
Unsuccessful
Reposition
Post Intubation
Management
BURP
Bougie
Blade/ETT Change
Unsuccessful
Rescue Techniques
Unsuccessful
Cricothyrotomy