02 Difficult Airway

Difficult Airway

1. Difficult to O2ate and ventilate (Difficult to Bag)
2. Difficult to intubate
3. Difficult to perform surgical airway

Failed airway
- failure to intubate 3x by experienced operator (can oxygenate adequately)
- failure to intubate, irrespective of the number of attempts if pulse oximetry can't be maintained above 90% by BVM ventilation

Predicting Difficult airway = tough
Look externally
Evaluate 3-3-2 rule
Mallampati
Obstruction
Neck mobility

Look external anatomy
Obese: less apnea time, head neck positioning, fatty airway, after paralysis fatty tissue collapses on airway
High Palate:
Narrow face: narrow space
Short/Thick neck: head neck positioning, short neck hard to surgical airway
Facial/Neck trauma:
Micrognathia: shortened mandible
Large tongue
Presence of facial hair
Poor dentition
Dentures
Large teeth

Evaluate 3-3-2 rule
aligns oral, pharyngeal, laryngeal axis
3 fingers between patient's teeth = 3-4 cm incisor to incisor opening for space
3 fingers between from mentum to hyoid bone = assesses mandible dimensions needed to access airway
2 fingers from thryoid notch to floor of the mouth = larynx low enought in the neck to permit access via oral route

Mallampati Score (tested while patient is upright)
Class I: sees tongue, hard palate, uvula, tonsillar pillars, posterior oropharynx
Class IV: only tongue and hard palate

Obstruction
Laryngeal tumor
epiglottitis
Peritonsillar abscess
Foreign body
Direct airway trauma
Extrinsic airway hematoma
prevertebral abscess
disruption of the airway integrity
hx of mouth or neck surgery
radiation of neck or jaw
hx of tumor, abscess or infection of mouth and neck

Neck mobility
Trauma patients = sniffing position is a no-no
Hx of prior neck surgery
RA or degenerative arthritis
Elderly


Cormack-Lehane Laryngoscopic Grading system link
Grade I: epiglottis and glottis/cords are seen
II: epiglottis and posterior part of glottis
III: only epiglottis = use bougie
IV: epiglottis nor glottis not seen

BURP maneuver: improves Cormack-Lehane by one grade

Sniffing position: OA/PA/LA aligns
neck flexion forward
extend head at the occiput

put some pillows under occiput: aligns external auditory meatus to sternum