The difficult airway

LEMON Mnemonic

1. Look- as in Diff to BVM
2. Evaluate 3-2-2
3. Mallampati
4. Obstruction
5. Neck Mobility

Mallampati Score

3-3-2 ruleDistance between patient's incisor teeth of 3 finger breadths anddistance between the thyroid notch and the floor of the mouth should be at least 2 finger widths

Look

1. trauma
2. short neck
3. micrognathia
4. prior surgery
5. may also be difficult to bag
   1. body mass index
   2. advanced age
   3. beard
   4. no teeth
   5. snoring

Evaluate

1. 3 finger-breadths mouth opening
2. 3 fingers from chin to hyoid
3. 2 from thryroid to sternum

ASA DIFF AIRWAY ALGORITHM

1. in OR, can always let pt wake up and cancel case
2. if can't do BVM after failed intubation- do cric or transtracheal jet since will desat otherwise
3. straight blade- Miller- better for deep glottis, buck teeth

Airway Adjuncts

Gum Bougie

Blind orotracheal intubation

Blind Naso Trach Intub

1. not as successful but still an option
2. higher complication rate- bleeding, emesis

Lighted Optical Stylets

1. high success rate- esp good for trauma, cspine
2. use for both reg and nasotrach
3. low complication rate
4. limited by fogging, secretion, recognition of anatomy, cost

LMA

1. can use without muscle relaxants
2. better than face mask
3. can be used as bridge to fiberoptic intubation
4. limited by unreliable seal at peak insp pressure
5. asp risk
6. mucosal trauma
7. LMA better than ett for paramedics
8. intubating LMA (ILMA) better for ventilating ED pts but intubating through ILMA more difficult for neophyte

Combitube- esoph obturator

1. good for nurses and paramedics
2. indicated if diff airway predicted, can't see glottis with laryngoscope,
3. reduced risk for aspiration compared to face mask or LMA
4. can maintain spinal immobilization
5. large size predisposes to esoph dilatation, laceration

Trans Trach Jet Vent

1. TTJV
2. needle through cric mem, connected to 50 psi 02- can ventilate and oxygenate ok
3. need adequate 02 pressure
4. 1 sec insp and 2- 3 sec exp to avoid breath stacking
5. may get ptx or barotrauma
6. contraindications- distorted anatomy, bleeding diathesis, complete airway obstr

Retrograde Intubation

1. perc guide wire through cric and retrograde intubation over wire
2. use guide catheter over wire and then ett
3. need time to set up
4. risk hematoma, ptx
5. contra- bleeding, distorted anatomy

Fiberoptic Bronchoscopic Intubation

1. takes time to set up
2. good for c-spine injury or awake pt with diff airway
3. go through nose
4. use for all ages, can give 02 during procedure thru fiberscope, immediate confirmation of position
5. limited by secretions, bleeding, poor suction,

Rigid Fiberoptic Laryngoscopes

1. use for diff airway or spinal immob
2. not as good and longer time to intubate than flex scope

Improving Passive Oxygenation

1. use in overweight, poor O2 reserve, hypoxia at baseline, concerns for rapid progression to hypoxia once apnea
2. Pre oxygenate while sitting upright, only lay back once RSI drugs pushed.
3. 30 degrees reverse trendelenburg position for intubation
4. Nasal O2 while pre oxygenating and DURING intubation (after induction increase to 15L)

Surgical Airway

1. can get subglottic stenosis
2. rapid 4 step procedure faster but higher compl rate- cric cart fx
3. can also do wire guided
4. long term morbid, mortality similar to tracheostomy

See Also

• Intubation
• LMA

Source

7/06 MISTRY NODESAT Study