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CHAPTER 42

Paediatric Upper Airway Obstruction

Andrew P. Freeland
John Kimario

Introduction Congenital Upper Airway Obstruction
Upper airway obstruction in children is a serious and a potentially life- Choanal Atresia
threatening problem. As such, the most important aspect is to establish
Choanal atresia is due to failure of the buccopharyngeal membrane to
the level of obstruction to instigate appropriate treatment without wor-
canalise in embryonic life. This may leave a membranous or bony atre-
rying too much about the diagnosis in the first instance.
sia or occasionally just a stenosis. It is often seen with the CHARGE
Listening to the breathing is vital.
association. (CHARGE is an acronym for coloboma, heart defects,
Stertor is a pharyngeal noise that sounds like a rough, bubbly snore
choanal atresia, developmental retardation, genitorenal defects, and ear
and is usually inspiratory. Swellings in the pharynx, such as tonsillitis,
abnormalities.) It may be unilateral or bilateral. If the atresia is unilat-
glandular fever, burns, diphtheria, and space-occupying lesions (e.g.,
eral, there is usually no need for any acute treatment and feeding and
lymphoma) will often have stertor. Obstruction at this level can be
a good airway is possible by suction of mucus from the patent nasal
bypassed with intubation or tracheostomy.
airway. If bilateral, the oral airway is kept in place and oral tube-feeding
Stridor can be inspiratory, bifid (two way), or expiratory:
may be necessary until surgery can be carried out in the first few days
• Inspiratory stridor is usually caused by problems at the vocal cord of life, provided the child is fit enough and features of the CHARGE
level and above. It can be relieved by intubation or tracheostomy. association have been excluded.
• Bifid stridor may involve the larynx but comes largely from the Diagnosis
trachea, which is not distensible, hence the two-way nature of the Since babies are obligate nose breathers bilateral atresia presents
noise. It may be relieved by intubation or tracheostomy providing acutely at birth. If the standard midwife practice is followed and nasal
the lesion is not at the distal end of the trachea. catheters are routinely passed the obstruction is easily diagnosed.
• Expiratory stridor is termed bronchospasm, and comes from the Management
bronchus. It is due to an inhaled bronchial foreign body and cannot The first aid management is to introduce an oral airway. If computed
be relieved by tracheostomy or intubation. tomography (CT) scanning is available, the nose is cleared of mucus by
suction prior to the scan to allow the radiologist a clear view to deter-
Neonates are obligate nose breathers and congenital bilateral
choanal atresia (see below) is therefore an acute airway problem that mine whether it is a stenosis or a bony or membranous atresia. If there is
needs immediate recognition and management. no CTscanner, then a plain x-ray, instilling a drop of radio-opaque dye
The volume of the noise of breathing is not important, but the into the previously cleaned out nose with the child supine will give an
breathing characteristics (quality) are important. In addition, a rising indication as to whether there is a stenosis or atresia present.
pulse and respiratory rate with increasing recession of intercostal Surgery
muscles and indrawing of the neck are signs that the obstruction is There are many ways of dealing with the problem of upper airway
worsening. Cyanosis is a very late sign and one of impending doom. obstruction, but the most sophisticated is via endoscopic nasal surgery
The minimal requirements for successful management of upper by using minute endonasal drills, but these are not always available.
airway obstruction are: The technique described here, however, is reliable and safe with the
equipment readily available.
• oxygen;
Under general anaesthesia (GA) and with the child intubated, the
• hydrocortisone and/or dexamethasone; mucosa of the nose is vasoconstricted with 0.5% ephedrine nose drops.
• nebulised adrenaline (epinephrine); The child is placed supine, and a tonsil gag is used to open the mouth.
Curved urethral bougies are gently passed through the nose, using a
• antibiotics: chloramphenicol, ampicillin, and/or cefuroxime; and small size first with the curved tip pointing to the nasal surface of the
• facilities and an ability to perform endotracheal intubation and tra- hard palate. Even if there is a bony stenosis, it is penetrated easily and
cheostomy. the tip of the bougie appears in the oral cavity from behind the soft
palate. Gradually, larger bougies are introduced to dilate the atresia.
Classification Finally, it is necessary to splint the stenosis open with cut-down
For convenience it is easier to think along the lines of congenital and endotrachael tubes, which will need regular suctioning and should stay
acquired airway obstructions. The congenital group normally presents in place for about a month.
at birth. The acquired group can be divided into acute and chronic. Results
The acute group is further divided into infective or noninfective upper Sadly, all techniques often need revision, and this one is no exception.
airway obstruction.
The revision rate is about 33%. By the time the child reaches about 3
months of age, oral breathing is established and the acute problem is over.