Question 5

Outline the important anatomic features that affect airway management in the paediatric airway and, where appropriate, strategies that may be used to overcome these.

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College Answer

  • Prominent occiput - Causes some neck flexion in the supine position. This can interfere with attempts to visualize the glottic opening during laryngoscopy. Placing a towel roll under the shoulders can improve airway alignment.
  • Large tongue - Infants and young children have large tongues relative to the size of the oral cavity. Can cause airway obstruction and interfere with laryngoscopy.
  • Larger tonsils and adenoids - Can cause airway obstruction. Placement of nasal airway may cause bleeding and aspiration.
  • Superior laryngeal position - located opposite the C3 to C4 vertebrae, compared with the C4 to C5 in adults. Visualization of glottis more challenging.
  • Large, floppy epiglottis - the epiglottis projects into the airway and covers more of the glottis. A straight blade needed to directly lift the epiglottis for improved visualisation during direct laryngoscopy.
  • Short trachea - The short trachea predisposes to right endobronchial intubation or inadvertent extubation. Use of formula (age/2 +12 cm from lower lip) to estimate tube length. Special attention to fixation.
  • Narrow trachea - Small decreases in the airway size from secretions, oedema, or external compression will cause obstruction. The needle or surgical cricothyroidotomy technically challenging in infants and children. (0.5)
  • Anatomic subglottic narrowing - this narrowing can create an effective anatomic seal without the need for a cuffed ETT. Foreign bodies can become lodged below the cords.

Additional Examiners’ Comments: Some candidates did not read the question thoroughly and did not include strategies in their answer

Discussion

The master list of ways in which a child's airway poses a problem:

Anatomical Peculiarities of the Paediatric Airway
And strategies that may be used to overcome these.
Anatomical problem How this is a problem Strategy to overcome this problem
Prominent occiput Neck is flexed in the supine poistion. 
Laryngoscopy will be difficult in this position.
  • Placing a towel roll under the shoulders can improve airway alignment.
  • There is no need for a pillow under the head. 
    The best position is a neutral position
Small mandible Less anterior excursion; smaller mouth opening
  • Narrow small laryngoscope blade
Large tongue Large tongue relative to the size of the oral cavity. Causes airway obstruction and interferes with laryngoscopy.
  • Earlier use of oropharyngeal airways is called for.
  • Mouth should be kept open during bag ventilation (it keeps the tongue from causing an obstruction). No pressure should be applied against the floor of the mouth.
Larger tonsils and adenoids Can cause airway obstruction. Nasopharyngeal airways may cause bleeding and aspiration.
  • Spray with co-phenylcaine; use copious amounts of lubricant
  • Use CPAP, 10-15cm to overcome the obstruction
Superior laryngeal position Located opposite the C3 to C4 vertebrae, compared with the C4 to C5 in adults. Laryngoscpy is made more difficult.
  • "Sniffing position" is of no benefit
  • External manipulation may be required, i.e. a BURP manoeuvre
Large, floppy epiglottis The epiglottis projects further into the airway and covers more of the glottis (until the age of 4)
  • A straight blade is needed to directly lift the epiglottis f during direct laryngoscopy.
Short trachea Easy to intubate the right main bronchus.
Easy to inadvertently  extubate the child.
  • Use the formula (age/2 +12 cm from lower lip) to estimate tube length.
  • Pay special attention to tube fixation.
  • Carefully monitor tube depth markers
Narrow trachea  More predisposed to obstruction: small decreases in the airway size will cause obstruction.
The needle or surgical cricothyroidotomy is more difficult, as the target is smaller. 
One should also be concerned about the risk of tracheal stenosis following prolonged intubation or tracheostomy.
  • Use a small diameter bougie.
  • Defer surgical airways to ENT staff
Soft trachea and cricoid Cricoid pressure may collapse the airway
  • Don't use cricoid pressure.
    Or use less pressure.
Anatomic subglottic narrowing An effective anatomic seal can be expected without the need for a cuffed ETT. Foreign bodies can become lodged below the cords. This resolves by age 10-12.
  • Use an uncuffed ETT

References

Heard, A. M. B., R. J. Green, and P. Eakins. "The formulation and introduction of a ‘can't intubate, can't ventilate’algorithm into clinical practice." Anaesthesia64.6 (2009): 601-608.

Stacey, Jonathan, et al. "The ‘Can't Intubate Can't Oxygenate’scenario in Pediatric Anesthesia: a comparison of different devices for needle cricothyroidotomy.Pediatric Anesthesia 22.12 (2012): 1155-1158.

Weathers E., "The Anatomy of the Pediatric Airway" 2010 -RC EDUCATIONAL CONSULTING SERVICES, INC.

Santillanes, Genevieve, and Marianne Gausche-Hill. "Pediatric airway management." Emergency medicine clinics of North America 26.4 (2008): 961-975.

HOLM‐KNUDSEN, R. J., and L. S. Rasmussen. "Paediatric airway management: basic aspects." Acta Anaesthesiologica Scandinavica 53.1 (2009): 1-9.

Cardwell, Mary, and Robert WM Walker. "Management of the difficult paediatric airway." BJA CEPD Reviews 3.6 (2003): 167-170.