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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? Cases. Case.
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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? • 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”
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 • Beardmask seal issues • Obeselung/chest wallcompliance • Older head/neck position • Toothlessmask seal • Snores/Stridorobstruction ‘BOOTS’
Predicting Difficult Laryngoscopy and Intubation MMAPthe airway: • Mallampati and Measure 3-3-1 • A-O extension • Pathologicconditions ‘MMAP’
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
Pre-oxygenation combining high flow nasal canula and a non-rebreather 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!
“NO DESAT” Nasal Oxygen During Efforts Securing ATube
“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, 6, 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
Important pediatric numbers: Age 4 • ET Tube size: • ET Tube depth: + 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
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 !!
Can’t Intubate Can Ventillate Can’t Intubate Can’tventillate Two Possible Scenarios
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
Advantages Airway maintained Breathing continues Stable hemodynamics Disadvantages Can be difficult Cooperation Adverse reflexes (GI/CNS/CVS) ‘Awake’ intubation …Intubation with topical airway anesthesia and light sedation.
Rescue ventilation devices: LMA www.lmana.com
Rescue techniques • Glide Scope® • LMA • I-LMA • Lighted Stylet • EsophagotrachealCombitube • Retrograde Intubation • Fiberoptic Intubation
Cricothryotomy Contraindications: • Distorted neck anatomy • Pre-existing infection • Coagulopathy • +++ difficult in pts < 10 yrs of age Relative Contraindications!
What equipment do you need? • Scalpel • Tracheal dilator (Trousseau dilator) or spreader • Tracheal hook • Portex or Shiley tube (No. 5-6 in adult)
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?
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