Question 11

A 6 year old girl develops respiratory distress post extubation  following a neurosurgical procedure. She does not respond to nebulized adrenaline and intravenous dexamethasone. She deteriorates rapidly and a decision is made to secure her airway. It is difficult to support her breathing with bag-mask ventilation. Laryngoscopy is performed and it is impossible to visualise her vocal cords and blind attempts  at intubation are unsuccessful.  Outline your approach to this problem.

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College Answer

- Call for help (Intensive care/Anaesthesia/ENT colleagues)
– Examine reasons for difficult laryngoscopy –
a) was she a difficult intubation in the 1st instance b) Poor positioning of head
c) Faulty suction, wrong laryngoscope blade
d) Use of wrong sized ETT through a swollen cords
- Important to recognise that people die from failed intubation because of failure to oxygenate, not failure to intubate
- Ensure ongoing bag-mask ventilation
- Use of LMA as an airway or as a conduit for fiberoptic intubation.
-If  LMA  not  successful,  try  reintubation  with  bougie  +  laryngeal  pressure  to  improve visualisation -
- If despite all of these, still cannot ventilate, consider cricothyroidotomy / tracheostomy

Additional points that may score marks
a) Attempt at intubation to be made with gaseous induction, two anaesthetists and full range of difficult intubation options, if it is safe to move to OT, but most PICUs can do this.
b) Mentioning that cricothyroidotomy is difficult in child
c) As nature of neurosurgery not known, mention of worsening ICP because of hypercarbia adds to the emergent nature of the situation

Discussion

This is a discussion of a "can't intubate, can't ventilate" algorithm.

Everybody should have one. ANZCA certainly suggests several. They dont specifically endorse any specific algortithm, but rather suggest that airway experts should have in their repertoir at least one.

For the answer to this question, I used the algorithm suggested by Heard et al.

In brief:

  • Call for senior anaesthetic help. The person with the best paediatric airway management expertise should intubate the child.
  • Explore alternatives to intubation. In the case of the child with an airway obstruction or stridor, this may consist of  the following options:
    • Heliox 
    • Adrenaline nebs
    • Steroids (if the aetiology calls for it)
  • Optimise pre-intubation management: This consists of adequate pre-oxygenation. It may be necessary for the child to be pre-oxygenated in the parents' lap
    • Sit up 90°
    • CPAP may help by reducing the dynamic component of stridor 
    • Atropine can be given (20 µg/kg) to dry secretions
  • Explore airway control options: 
    • Inhalational induction is usually Plan A. The whole point is to maintain spontaneous respiration throughout the process, using gas to attain a level of anaesthesia which permits intubation. Best to induce them in a sitting position. Be prepared to wait- gas induction is slow in airway obstruction. When the patient is ready, they are rapidly made supine and intubated by laryngoscopy.
    • IV induction with paralysis is usually Plan B.
    • If unable to intubate, proceed to LMA. If LMA ventilation is sucessful, one can prepare for a repeat attempt at intubation, with a variety of difficult intubation equipment avalable, senior staff on standby, and with manoeuvres to improve visibility (eg. improved head position, BURP, videolaryngoscopy)
    • If unable to ventilate with LMA, proceed to needle cricothyroidotomy. This is difficult in children. Skileld proceduralists only seem to have a 60% success rate, and puncture the posterior wall of the trachea about 47% of the time.
    • If jet oxygenation can be accomplished, one has some time to set up for a Seldinger dilation and insertion of a pediatric ETT, or for a retrgrade intubation.
    • If jet ventilation cannot be accomplished, one must assess the difficulty of anterior neck anatomy.
      • if the anatomy is easy, one can proceed to a scalpel-bougie tecnique (where one makes an incision in the cricothyroid membrane and railroads the tube in over a hollow jet ventilation bougie)
      • if the anatomy is difficult, one must perform a scalpel-needle cricothyroidotomy (where the cricothyroid membrane is identified by palpation through an incision, so that the jet cannula can be inserted)
  • Optimise team communication: Ensure all team personnel are aware of the algorithm and understand the steps.
  • Optimise first attempt:
    • Videolaryngoscopy
    • Skilled staff present and briefed about Plan A and Plan B
  • Optimise subsequent attempts:
    • Checked equipment with backup models
    • Senior anaesthetist and ENT surgeon available
    • Ensure availability of ultra-fine (~ 2mm) intubating bronchoscope for paediatric work

References