The Emergency Airway National Review Course in Emergency Medicine Kirk Magee MD, MSc, FRCPC Associate Professor Dalhousie Department of Emergency Medicine

Outline: Recognition: is this an airway question? Recognition: is this an airway question? Cases Cases

Case A 35 year old female presents to the ED with an altered LOC. She was found surrounded by empty pill bottles 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 Vital Signs: HR 130, BP 115/78, sats 98%, GCS 6/15 Is this an airway question? Is this an airway question?

Types of Airway questions Recognition of the need for an airway Recognition of the need for an airway Description of RSI and recognition of relative contraindications Description of RSI and recognition of relative contraindications Recognition and management of a difficult airway Recognition and management of a difficult airway Post intubation management Post intubation management Approach to the failed airway Approach to the failed airway

How to drive an examiner nuts… “I would perform an RSI with a double set-up” “I would perform an RSI with a double set-up”

Exam triggers to the difficult airway: Morbidly obese Morbidly obese Trauma to head or neck Trauma to head or neck Burns Burns Stridor Stridor Prior unsuccessful attempts Prior unsuccessful attempts Asthma Asthma Anaphylaxis Anaphylaxis

Beware… BMV Laryngoscopy

Difficult Mask Ventilation Beard mask seal issues Beard mask seal issues Obese lung/chest wall compliance Obese lung/chest wall compliance Older head/neck position Older head/neck position Toothless mask seal Toothless mask seal Snores/Stridor obstruction Snores/Stridor obstruction ‘BOOTS’

Predicting Difficult Laryngoscopy and Intubation MMAP the airway: M allampati and M easure M allampati and M easure A -O extension A -O extension P athologic conditions P athologic conditions ‘MMAP’

Lets get ready to rumble!

Cases

Case 1 34 yo asthmatic presents with severe respiratory distress 34 yo asthmatic presents with severe respiratory distress Normal airway Normal airway VS: 122, 32, 156/90 VS: 122, 32, 156/90

Special Considerations Percipitating causes: Percipitating causes: –Pneumothorax, mucous plug –Role of epinephrine Difficult/impossible to BMV Difficult/impossible to BMV Permissive hypercapnea Permissive hypercapnea Ketamine Ketamine Apneic oxygenation Apneic oxygenation

Apneic Oxygenation

Pre-oxygenation combining high flow nasal canula and a non- rebreather mask Measured inspired oxygen 15 lpm only 60-70% Measured inspired oxygen 15 lpm only 60-70% –Pt’s expired gasses are mixing with applied O 2 in nasopharynx High flow nasal O 2 flushes the nasopharynx with O 2 High flow nasal O 2 flushes the nasopharynx with O 2 –When pt inspires, inhale higher percentage of inspired O 2 Small changes in FiO 2 create dramatic changes in the availability of O 2 at the aveolus Small changes in FiO 2 create dramatic changes in the availability of O 2 at the aveolus

Apneic Oxygenation Alveoli will continue to take up O 2 even without diaphragmatic movments Alveoli will continue to take up O 2 even without diaphragmatic movments Optimal circumstances: PaO 2 can be maintained at > 100 mmHg for up to 100 minutes without a single breathe! Optimal circumstances: PaO 2 can be maintained at > 100 mmHg for up to 100 minutes without a single breathe!

“NO DESAT” Nasal Oxygen During Efforts Securing A Tube

“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 4 yo presents with a 3 day hx of fever and “flu-like” symptoms Unable to arouse Unable to arouse VS: 139, 6, 60/40 VS: 139, 6, 60/40

Special Considerations Not just “little adults” Not just “little adults”

The Pediatric Airway Smaller airway Smaller airway Large occiput Large occiput Tongue is larger Tongue is larger Larynx is relatively cephalad in position Larynx is relatively cephalad in position Epiglottis is more floppy Epiglottis is more floppy < 10 yrs, narrowest portion of airway is below vocal cords < 10 yrs, narrowest portion of airway is below vocal cords Higher basal metabolic rate Higher basal metabolic rate bradycardia bradycardia

Important pediatric numbers: ET Tube size: ET Tube size: ET Tube depth: ET Tube depth: Age4 Age2 + 4 Breslow Tape

Case 3 26 yo Type 1 diabetic 26 yo Type 1 diabetic Florid DKA, not protecting his airway Florid DKA, not protecting his airway VS: 127, 28, 95/66, 95% VS: 127, 28, 95/66, 95%

Special Considerations Hyperkalemia Hyperkalemia Post-intubation still need high respiratory rate Post-intubation still need high respiratory rate –DKA –ASA overdose

Contraindications to Sux Hyperkalemia Hyperkalemia Burns > 10% BSA Burns > 10% BSA Crush injury Crush injury Denervation Denervation Neuromuscular disease Neuromuscular disease –ALS, MS Malignant hyperthemia Malignant hyperthemia

Case 4 50 yo pulled from burning car 50 yo pulled from burning car Significant burns to face, stridor Significant burns to face, stridor VS: 112, 28, 132/88, 88% VS: 112, 28, 132/88, 88%

Special Considerations Difficult airway Difficult airway Toxicology Toxicology –CO –CN

MMAP: Pathological Obstructing Conditions… e.g. Periglottic edemae.g. Glottic trauma

MMAP: Pathologically Obstructing Conditions… …with deep sedation may be impossible to BMV or intubate !!

Two Possible Scenarios Can’t Intubate Can’t Intubate Can Ventillate Can Ventillate Can’t Intubate Can’t Intubate Can’t ventillate Can’t ventillate

What are your options? If not contraindicated, RSI may actually improve success rate If not contraindicated, RSI may actually improve success rate –Double set-up Are you the right person, is the ED the right location? Are you the right person, is the ED the right location? Awake intubation Awake intubation

‘Awake’ intubation Advantages Airway maintained Airway maintained Breathing continues Breathing continues Stable hemodynamics Stable hemodynamicsDisadvantages Can be difficult Can be difficult Cooperation Cooperation Adverse reflexes (GI/CNS/CVS ) Adverse reflexes (GI/CNS/CVS ) …Intubation with topical airway anesthesia and light sedation.

Rescue device: Glide Scope ®

Rescue ventilation devices: LMA

Rescue ventilation devices: I-LMA

Rescue devices: Lighted Stylet

Rescue techniques Glide Scope ® Glide Scope ® LMA LMA I-LMA I-LMA Lighted Stylet Lighted Stylet Esophagotracheal Combitube Esophagotracheal Combitube Retrograde Intubation Retrograde Intubation Fiberoptic Intubation Fiberoptic Intubation

Can’t ventilate, Can’t intubate

Cricothryotomy Contraindications: Distorted neck anatomy Distorted neck anatomy Pre-existing infection Pre-existing infection Coagulopathy Coagulopathy +++ difficult in pts < 10 yrs of age +++ difficult in pts < 10 yrs of age Relative Contraindications!

What equipment do you need? Scalpel Scalpel Tracheal dilator (Trousseau dilator) or spreader Tracheal dilator (Trousseau dilator) or spreader Tracheal hook Tracheal hook Portex or Shiley tube (No. 5-6 in adult) Portex or Shiley tube (No. 5-6 in adult)

Decribe how you would perform a cricothyrotomy

Case 5 72 yo with altered LOC and urosepsis 72 yo with altered LOC and urosepsis Normal airway Normal airway VS: 124, 20, 70/40 VS: 124, 20, 70/40

Special Considerations CBA not ABC! CBA not ABC! –Maximize BP first Relative contraindication for etomidate? 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 26 yo mountain biker “clothes-lined” on wire fence at high speed Pt is unable to talk; obvious respiratory distress Pt is unable to talk; obvious respiratory distress Edema and echymosis evident at his neck Edema and echymosis evident at his neck VS: 115, 26, 160/85, 88% VS: 115, 26, 160/85, 88%

Special Considerations The “most difficult” airway! The “most difficult” airway! Patent airway may be lost with deep sedation/paralysis Patent airway may be lost with deep sedation/paralysis How does the scenario change with: How does the scenario change with: –Time from injury –Community vs Urban ED –“stable” vs. “unstable”

Your 1 st attempt should not be in Ottawa at the exam centre!

Putting it all together Preparation – predictors of difficult BMV/laryngoscopy Preparation – predictors of difficult BMV/laryngoscopy Preoxygenate – no BMV Preoxygenate – no BMV Paralysis and induction agent Paralysis and induction agent Placement of tube and confirmation Placement of tube and confirmation Post tube management Post tube management

Putting it all together… Assess predictors of difficult BMV/laryngoscopy Pre-oxygenate Paralytic/Induction Agent Reposition BURP Bougie Blade/ETT Change Confirm Tube Placement Rescue Techniques Post Intubation Management Cricothyrotomy Unsuccessful

Difficult Laryngoscopy and Intubation: Putting it all together…