Anesthesia – Airway Assessment In ED

Last Updated on by frcemuser

History and Examination

H: History including previous airway problems
A: Anatomy anatomical features that may cause difficulty
V: Visual clues such as obesity and the presence of a beard
N: Neck mobility and accessibility (including immobilization)
O: Opening of the mouth
T: Trauma

History and Examination


  • Previous problems with anaesthesia or sedation (look in the hospital and ED records if possible)
  • Stridor, snoring or sleep apnoea
  • Advanced rheumatoid arthritis
  • Chromosomal abnormality (e.g. trisomy 21)

Physical Examination:

  • Habitus
    • Significant obesity (especially involving the neck and facial structure)
  • Head and neck
    • Short neck, limited neck extension, decreased hyoid-mental distance (<3cm in an adult),
    • neck mass, cervical spine disease or trauma, tracheal deviation, dysmorphic facial features
    • (e.g. Pierre-Robin syndrome), excessive facial hair
  • Mouth
    • Small opening (<3cm in an adult, edentulous, protruding incisors, high arched palate, macroglossia, tonsillar hypertrophy and nonvisibule uvula)
  • Jaw
    • Micrognathia, retrognathia, trismus and significant malocclusion









Modified Mallampati Score
Class I: Soft palate, uvula, fauces, pillars visible
Class II: Soft palate, uvula, fauces visible
Class III: Soft palate, the base of uvula visible
Class IV: Only hard palate visible











Grade I: vocal cords are fully visible
Grade II: vocal cords are only partly visible
Grade III: the Only epiglottis seen, none of the glottis seen
Grade IV: Neither glottis nor epiglottis is seen

Direct laryngoscopy View Anatomy










Risk factors for difficult airway management

  • Poor preparation
    • Inadequate positioning
    • Poor availability of equipment
    • Lack of suitable personnel
    • Inadequate training
  • Patient Level of consciousness + co-operation
  • Infections of oropharynx and neck
  • Previous surgery or radiotherapy to neck
  • Problems with mouth opening – e.g. trauma, soft tissue disorders, arthridities
  • Problems with neck mobility – e.g. cervical spine disruption, rheumatoid arthritis, cervical fusion (e.g. operative, ankylosing spondylitis, scleroderma)
  • obesity, OSA
  • oropharyneal or neck masses
  • difficult dentition
  • pregnancy
  • recent intubation (swelling, trauma)
  • angioedema
  • craniofacial syndromes
  • Burns
  • Airway trauma – blunt or penetrating
  • Airway obstruction

Difficult airway assessment – mnemonics

Difficult intubation = LEMON

  • Look externally
  • Evaluate 3-3-2 rule
    • Inter incisor distance (3 fingers)
    • Hyoidmental distance (3 fingers)
    • Thyroid to floor of mouth (2fingers)
  • Mallampati score
  • Obstruction
  • Neck Mobility

Difficult BVM = BONES

  • Beard
  • Obese
  • No teeth
  • Elderly
  • Sleep Apnea / Snoring

Difficult LMA = RODS

  • Restricted mouth opening
  • Obstruction
  • Distorted airway
  • Stiff lungs or c-spine

Difficult surgical airway = SHORT

  • Surgery
  • Hematoma
  • Obesity
  • Radiation distortion or other deformity
  • Tumor


Airway Assessment

Difficult Airway Management

Was this article helpful?

Related Articles

Leave A Comment?

This site uses Akismet to reduce spam. Learn how your comment data is processed.