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278 Paediatric Upper Airway Obstruction

Unilateral cases need have no surgery until the child is 5 or 6years of occur between the anterior ends of the vocal cords. The presenting
age, and then only if unitateral nasal discharge is a problem. features are inspiratory stridor and a very weak voice. The web is often
Laryngomalacia thin and can be split surgically.
Laryngomalacia is the most common cause of neonatal obstruction. Posterior Laryngeal Cleft Larynx
The pathology is vague, but it is assumed that the laryngeal and often Posterior laryngeal cleft larynx is rare and difficult to diagnose and may
the tracheal cartilages are immature, resulting in lack of stiffness and range from a small defect in the interarytenoid muscles to a complete
support for the larynx on inspiration. division of the posterior arch of the cricoid. The symptoms are very
Clinical features similar to a tracheo-oesophageal fistula, and complex repair surgery is
Usually, there are no signs of obstruction until the baby is a few days necessary to stop aspiration.
old and becomes more active. Classically, there is an inspiratory stridor Haemangioma
only when the baby is agitated or crying. The stridor is more obvious Inspiratory or bifid stridor in a child with a cutaneous haemangioma
when the child is supine, and it improves when the child is prone. The should always raise suspicion of a laryngeal haemangioma. Diagnosis
voice is normal. Feeding can be difficult, however. is made via laryngoscopy; symptoms are often absent at birth but
Natural history become more severe as the lesion grows naturally. The commonest site
The vast majority of cases settle down within 6 months and no audible is the subglottis. Usually there is no more enlargement and at about
6–12 months, natural regression takes place and often no treatrment
stridor is presnt at 18 months of age. Failure to thrive is the main reason is necessary. If the airway is becoming compromised, a tracheostomy
to interfere.
while waiting for natural regression is the safest option.
Diagnosis External Compression
The classic history is usually enough for diagnosis, but if in doubt, Rare lesions, such as cystic hygroma (see Chapter 41), may compress
microlaryngoscopy under GA with spontaneous breathing is necessary. the pharynx, larynx, or trachea.
The findings are of an omega-shaped epiglottis that is pulled
backwards as the aryepiglottic folds are pulled forward on inspiration. Acquired Upper Airway Obstruction
This results in a supraglottic obstruction. The rest of the larynx and The acquired causes can be divided into acute or chronic. The acute
upper trachea are inspected to rule out coexisting lesions. causes can be further subdivided into infective or noninfective. The
Management infective causes will be pyrexial, and the noninfective will be apy-
If the failure to thrive is mild, a wait-and-see policy can be tried. rexial. A simple thermometer (not placed in the mouth) will distinguish
In more severe cases, aryepiglottopexy, which is an easy procedure between these two groups.
whereby the aryepiglottic folds are snipped with sharp micro scissors or Acute Acquired Airway Obstruction
divided with a laser, is a successful blood-free operation, usually with Acute noninfective upper airway obstruction
immediate results. Foreign bodies, burns, and angioneurotic oedema need to be considered.
Tracheostomy should be avoided because often there is coexistent
tracheomalacia, and extubation becomes very difficult. • Foreign bodies (FB) in any body cavity are common in children,
but an inhaled FB constitutes an emergency. There is usually a his-
Vocal Cord Palsy tory of ingestion or inhalation, and the child will be apyrexial. The
Bilateral abductor vocal cord palsy is very rare, but is sometimes asso- level at which the FB is trapped now needs to be determined.
ciated with hydrocephalus, causing prolapse at the foramen magnum
Gagging will be the main symptom of a pharyngeal FB, such
affecting the vagus nerves. Acute inspiratory stridor and a weak cry are
as a fish bone stuck in the tonsil. This may be seen and removed
present. Laryngoscopy will confirm the diagnosis and tracheostomy is
with forceps.
necessary.
Inspiratory stridor suggests the FB is at the laryngeal level, and
Unilateral palsy is usually on the left side and due to inadvertent
urgent removal by thumping the child on the back with the child
damage during ligation of a congenital patent ductus arteriosis. A weak cry
in the prone and head-down position or carrying out the Heimlich
and usually mild stridor are present, and if the recurrent laryngeal nerve
manoeuvre is mandatory.
has been traumatised rather than divided, it may recover in about 6 weeks.
The technique most useful for infants is as follows (see Figure 42.1):
Congenital Subglottic Stenosis 1. Lay child prone with head down over the knee.
Congenital subglottic stenosis is far less common than acquired steno- 2. Give five pats on the child’s back with the heel of the hand.
sis, which is often due to prolonged intubation in neonatal life. There 3. Check the child’s mouth for a foreign body that can be removed.
will often be a bifid stridor because the lesion is a congenital narrowing 4. Repeat.
of the only complete ring of the trachea, namely, the cricoid cartilage. The Heimlich manoeuvre for older children, to be used if the
The cry is normal, but due to respiratory distress, urgent intubation is technique shown in Figure 42.1 isn’t successful, is as follows
necessary when the expected diameter tube for the weight of the child (see Figure 42.2):
is determined to be too wide and a narrower tube is necessary, and often 1. Stand behind the child.
that is also too tight. 2. Make a fist with one hand and place it just below the child’s
Mild stenosis will often grow with the child, and no action is lower sternum.
necessary in early life. 3. Place your other hand over the fist.
More severe stenosis requires treatment. An anterior cricoid split is 4. Pull into and upwards to the child’s upper abdomen five times.
sometimes effective whereby a vertical incision is made through the 5. Check the child’s mouth for a foreign body that can be removed.
anterior arch of the cricoid and a larger endotracheal tube inserted as a 6. Repeat as necessary.
dilator for a period of time. Failing this, a tracheostomy will be necessary If either of these techniques is not successful and a skilled
and reconstruction of the trachea carried out at about the age of 2 years. laryngologist is not available, then emergency cricothyrotomy or
Laryngeal Web tracheostomy will be necessary to bypass the obstruction. A FB
A total laryngeal web is incompatible with life and is due to lack of lodged in the upper oesophagus may give very similar symptoms.
canalisation of the developing larynx. Additional minor webs usually Expiratory stridor preceded by bouts of coughing suggests