77. Stridor post-thyroidectomy

Question 1

You are called to recovery urgently to see a patient with stridor 1 hour
following a total thyroidectomy.
What are the common causes of stridor in this situation?

Answer 1

1. Wound haematoma

Bleeding is probably the most common cause of early stridor and can lead to life-threatening respiratory obstruction.

Removal of clips or sutures may help, or at least buy time,
but tracheal intubation will be required for serious cases.

2. Bilateral RLN palsy
   Unilateral damage will cause hoarseness, but
   bilateral damage will lead to adduction of both
   vocal cords and stridor
3. Tracheal oedema T
   his would be an unusual cause of stridor at such an
   early stage.
4. Tracheal collapse
   Tracheomalacia may occur intra- or post-operatively.
   It tends to occur more commonly in large or malignant goitres.

A clue to its presence may be observed at the end of the operation with the
absence of a leak around the cuff of the E.T. tube when it is deflated

Question 2

How would you manage this situation

Answer 2

The patient should be given 100% oxygen.
A consultant anaesthetist and ENT surgeon should be summoned
immediately.
If there is evidence of an expanding haematoma, the skin clips should be
removed, although it may be necessary to open deeper layers.
Nebulised adrenaline (5 mls of 1/1000, i.e. 5 mg) if there is a suspicion of
oedema.

The remaining causes would necessitate urgent tracheal intubation or
tracheostomy.

Question 3

The patient deteriorates further without evidence of haematoma and
requires intubation. How would you undertake this?

Answer 3

The anaesthetic management of this situation is contentious.
The options are:
Gas induction
i.v. induction followed by neuromuscular blockade.
Surgical airway

Question 4

Several factors may help when deciding on the most appropriate
management:

Answer 4

Time. The choice of technique will be limited by the speed of deterioration
of the patient and the availability of equipment.
Ability to achieve any ventilation. If ventilation is not possible and the
patient is becoming severely hypoxic, then gas induction is clearly not going
to be an option.
The most likely diagnosis. The surgeon who performed the operation would
know if tracheomalacia was likely – the operation note could help.
Tracheomalacia may be expected to be an easier intubation than airway
oedema.
The difficulty of the original intubation

Availability of a skilled ENT surgeon. If the wound is open, there is no
haematoma and if the surgeon is present, then a surgical airway could be
considered.

Question 5

Gas induction

Answer 5

If the patient is partially obstructed and therefore still self-ventilating, a gas
induction could be performed.

The patient should be immediately transferred to theatre, where facilities for difficult intubation are more readily available.

The patient is pre-oxygenated and gas induction of anaesthesia performed
with sevoflurane or halothane in 100% oxygen

The trachea can then be intubated under deep inhalational anaesthesia without a muscle relaxant.

The ENT surgeon should be scrubbed and ready to perform an emergency
tracheostomy if oral intubation is impossible.

Rigid bronchoscopy (by an experienced ENT surgeon) or
transtracheal jet ventilation may be used as
holding measures.