++
The larynx is a complex evolutionary structure that joins the
trachea and the bronchi to the pharynx as a common aerodigestive
pathway. The larynx serves the essential functions of (1) ventilation
of the lungs, (2) protection of the lungs during deglutition by
its sphincteric mechanisms, (3) clearance of secretions by a vigorous
cough, and (4) vocalization. An infant’s survival is predicated
on the structural and neurological integrity of the larynx, and
prompt diagnostic and surgical intervention for airway management
is mandatory.
++
The larynx is arbitrarily divided into three regions: supraglottis,
glottis, and subglottis. The supraglottic larynx is composed of
the epiglottis, aryepiglottic folds, arytenoid cartilages, vestibular
folds (false vocal folds), and laryngeal ventricles. The glottis
comprises the vocal folds, or “vocal cords.” The
subglottic region extends from the undersurface of the vocal folds
to the base of the cricoid cartilage and represents the smallest
diameter of the infant larynx. When an infant is born, the larynx
is approximately one third the size of the adult larynx. The vocal
folds are 6 to 8 mm long, with the posterior aspect composed of
the cartilaginous process of the arytenoid. The subglottic diameter
measures approximately 4.5 by 7 mm. A diameter of less than 3.5
mm is suggestive of a subglottic stenosis.
++
In the infant, the superior border of the larynx is located as
high as the first cervical vertebra (see Fig.
371-2). This superior location of the larynx elevates the epiglottis
approximately to the level of the palate and helps to explain obligate
nasal breathing over the first few months of life. An intranarial
larynx creates a partially separate respiratory and digestive tract
that mimics lower animal forms. This position is further enhanced
in nursing, as forward thrust of the tongue causes increased elevation
of the larynx. The child’s and adolescent’s larynx
gradually lowers into the neck and enlarges this supralaryngeal
region of the pharynx to better accommodate the varied sounds of
human speech. The descent of the larynx and elongation of the vocal
tract has yielded a trade-off between the advantages of speech production
and an increased risk of aspiration. This is most evident in infants
and toddlers. Ultimately, in humans, the vocal folds have evolved
the highest degree of versatility for voice production by their
ability to adjust length, tension, and shape.
++
+++
Approach to
the Child with Airway Obstruction
++
Evaluating the child with airway obstruction requires a careful
history, physical examination, and knowledge of the functional anatomy
of the upper airway. Important points in the history and physical are
summarized in Table 371-2. Age of onset and
duration of stridor are important indicators as to which of the
congenital causes of the condition is most likely. A history of
intubation may indicate subglottic stenosis. Laryngomalacia is the
most common cause of congenital stridor and has a characteristic
history of the child breathing more comfortably when relaxed and
being more stridorous when agitated. Birth injury or neurological
abnormalities may indicate vocal fold paralysis. Acute stridor in
the older child may be caused by a foreign body or acute infection.
++
++
Symptoms vary depending on the site of obstruction, as outlined
in Table 371-3. Although stridor, a high-pitched
noise with respiration, is the most common sound exhibited by children
with airway obstruction, this first should be differentiated from
stertor. Stertor is a lower-pitched nose that originates from the
nasal cavity or nasopharynx and is associated with obstruction at
these sites. Pathology such as adenoid hypertrophy, choanal atresia,
nasal polyps, turbinate hypertrophy, or other nasal masses are associated with stertor. An algorithm
for evaluating a child with airway obstruction and stridor is shown
in Figure 371-3, and causes of airway obstruction
are listed in Table 371-4.
++
++
++
++
Careful inspection of the patient is the first priority in any
infant with difficulty breathing. The child should remain in the
parent’s arms, and the physician can judge the respiratory
rate and degree of distress. The physician should look for tachypnea
or the onset of fatigue, which may portend respiratory collapse.
Flaring of the nasal alae and using accessory neck or chest muscles
indicate that an increased degree of respiratory effort is needed
to maintain an oxygenated state. Cyanosis and air hunger, particularly
from supraglottic infection or from a foreign body, will cause the
patient to sit with the neck hyperextended in an attempt to improve
airflow. The patient should be permitted to maintain such a posture.
In a gravely ill child, additional examination should not be undertaken
lest it precipitate respiratory arrest. The child requires prompt
transport to an appropriate hospital.
++
In a well-oxygenated, stable child, additional examination can
proceed. An important part of the assessment is auscultation that
is performed both with the ear and with the stethoscope. Sequential
listening over the nose, open mouth, neck, and chest can localize
the probable site of obstruction, which is indicated by a heightened
sound intensity. Attention is next directed to the respiratory cycle,
which normally is composed of a shorter inspiratory phase and a
longer expiratory phase. Laryngeal obstruction is usually associated
with inspiratory noises, whereas bronchial obstruction has characteristic
expiratory noises or wheezes. Similarly, in laryngeal obstruction,
the time of inspiration is lengthened, whereas in bronchial obstruction,
expiration tends to be prolonged. Subglottic and tracheal obstruction
will often cause both inspiratory and expiratory stridor.
++
In addition, the infant should be placed in various positions
to determine the effect on the stridor. The stridors of laryngomalacia,
micrognathia, macroglossia, and vascular compression diminish when the
baby lies prone with the neck extended. The presence and quality
of the voice or cry can help to identify laryngeal causes of stridor.
A weak cry suggests causes related to the vocal fold or indicates conditions
with poor pulmonary function. Although laryngeal lesions are most
often accompanied by voice changes, a normal voice does not rule
out a laryngeal cause for stridor. For example, with bilateral vocal
cord paralysis, there may be a normal voice but marked airway
obstruction.
++
Certain maneuvers can be performed to determine the nature of
the obstruction. If stridor is present at birth, the first maneuver
should be to open the mouth and pull the mandible and tongue forward. If
the stridor lessens, the obstruction is at the level of the larynx
or higher. Nasal catheters should be passed to determine the patency
of the nasopharyngeal airway. In patients with choanal atresia,
the placement of an oral airway will help to diagnose the disorder
and to bypass the obstruction. Introducing a blade laryngoscope
will lift the laryngeal structures and decrease the stridor of laryngomalacia but
will not relieve the obstruction of vocal cord paralysis or subglottic
stenosis. Pulling the mandible and tongue forward will often relieve
the obstruction seen in the Pierre-Robin sequence and other conditions
associated with mandibular hypoplasia, and emergency placement of
a nasopharyngeal airway will maintain the patient until a long-term
care decision can be made.
++
Diagnostic testing of the infant with stridor always begins with
flexible fiberoptic nasopharyngoscopy while awake; this is the most
useful and comprehensive of all diagnostic tools available. This
test should be performed in all patients with suspected airway pathology.
It can be done in even the smallest child and can usually be performed
in an office or clinic setting. Vocal fold mobility, laryngeal masses,
laryngomalacia, and other laryngeal problems are easily assessed.
The examination begins in the anterior nasal cavity to rule out
a pyriform aperture stenosis and moves posteriorly in the nose to
rule out a choanal stenosis or atresia. The nasopharynx can be examined
for adenoid hypertrophy or other mass lesions. Hypopharyngeal visualization
will assess the hypopharyngeal tone. The epiglottis and arytenoid
cartilages can be evaluated for edema or erythema consistent with
reflux esophagitis or infection. In addition, any evidence of laryngomalacia
will be noted. Determining the mobility of the true vocal folds
is an essential part of this evaluation. A subglottic view is possible
with a flexible scope in most cases, but subglottic and distal airway
evaluation with endoscopy is best reserved for the operating room
in severely affected children.
++
Radiographic evaluation provides useful information about the
subglottis, trachea, and larger bronchi and therefore complements
the flexible endoscopic examination. Lateral and anteroposterior
plain films of the neck demonstrate the patency of the airway lumen
and the presence of mass lesions. The anteroposterior high-kilovoltage
technique is particularly useful for depicting the upper airway,
as it enhances the tracheal air column and deemphasizes the bony
cervical spine. Videofluoroscopy may be helpful for evaluating dynamic
airway problems such as hypopharyngeal collapse and tracheomalacia.
The barium swallow is useful to detect aspiration related to vocal
cord paralysis, posterior laryngeal cleft, or H-type tracheoesophageal
fistula and external compression from vascular lesions. CT and magnetic
resonance imaging (MRI) are useful for obtaining specific information
in selected cases (eg, vascular compression of tracheobronchial
tree) but are not a substitute for endoscopic evaluation. A diagnosis
is usually established by the above studies. Diagnostic rigid endoscopy
is needed when (1) the diagnosis remains in question, (2) the previous
evaluation suggests a subglottic lesion, and (3) a second significant
distal lesion in the airway is suspected in addition to the diagnosis
of a more obvious proximal lesion in the upper airway. Rigid airway
endoscopy may also be necessary for therapy (eg, for removing laryngeal
papillomas).
+++
Congenital Malformations
++
The clinical manifestations associated with congenital anomalies
of the larynx include respiratory obstruction, stridor in infants
or hoarseness in older children, a weakened or abnormal cry, dyspnea, tachypnea,
aspiration, and sudden death.
++
The pathogenesis of laryngomalacia, which is the most common
cause of stridor in the newborn, is not completely understood. The
cartilages of the infantile larynx are very flexible. As the infant
inspires, the laryngeal skeleton is not stiff enough to keep the
laryngeal lumen fully open. The infant epiglottis assumes a pronounced
tubular or omega shape, and the aryepiglottic folds and false vocal
cords are drawn into the laryngeal lumen, which results in a substantial
narrowing of the lumen on inspiration. This narrowing accounts for
the high-pitched stridor heard in these infants see video at: http://www.youtube.com/watch?v=2tYZ7oftfh4 (accessed
January 1, 2010). The stridor of laryngomalacia may be present at
birth but more often occurs about several weeks after birth and
increases in severity. The child breathes more comfortably when relaxed
and is usually more stridorous when agitated. The noise may be lessened
when the child is on his or her side or when prone and worsens when
supine.
++
Once other causes for stridor are ruled out, the treatment of
this condition is usually close observation. As the child grows,
the cartilages become more rigid and support the larynx, so the
stridor resolves. Most children will outgrow the condition by 12
to 18 months. More severe laryngomalacia may cause failure to thrive
secondary to airway obstruction and poor feeding or nighttime obstructive
symptoms with significant oxygen desaturation. In these relatively
rare cases, surgical trimming of the supraglottis (supraglottoplasty)
is recommended. However, in most infants, positioning and using
high-calorie formula will avoid the need for surgical intervention.
+++
Tracheobronchomalacia
++
Tracheomalacia is an abnormal collapse of the trachea severe
enough to produce symptoms of airway obstruction. Similarly, bronchomalacia is
airway collapse in the bronchi and tracheobronchomalacia involves
both. Mild tracheobronchomalacia is common and self-limited, whereas
severe tracheobronchomalacia is life-threatening, and heroic measures
may need to be considered, such as tracheostomy with positive-pressure
ventilation. Tracheobronchomalacia may be primary or secondary to
other pathology (eg, tracheoesophageal fistula, cardiac and vascular
abnormalities, or cervical or mediastinal masses). Usually no treatment
is required for primary tracheobronchomalacia, as the disease is
self-limiting with resolution over a few years. Parents require
substantial support and education, including teaching them cardiopulmonary
resuscitation, especially if the child has recurrent episodes of
apnea and obstruction. In severe cases of tracheobronchomalacia,
the potential risks and benefits of any therapies need to be carefully
balanced.
++
Congenital subglottic stenosis can cause significant stridor
in the neonate or in the early months of life. Narrowing of the
subglottic airway can occur for the following reasons: the first
tracheal ring is trapped within the cricoid cartilage, there is
a deformity of the cricoid cartilage, or there is excess soft tissue
within the cricoid cartilage. The diagnosis is made by rigid endoscopy
under general anesthesia.
++
Only stenosis sufficient to produce signs of respiratory distress
requires treatment. In the past, treatment often meant a tracheostomy
and waiting for the subglottic space to grow with the child. Currently,
if the obstruction is sufficiently severe to require a tracheostomy,
early surgical correction may avoid this procedure. In contrast,
acquired subglottic stenosis from intubation injury often requires
a tracheostomy with subsequent surgical correction to achieve decannulation.
These children are often graduates of the neonatal nursery and have
many other medical problems that need to be managed. Laryngeal-tracheal
reconstruction for these complex airway abnormalities, provided
today in most tertiary referral pediatric centers, has a high success
rate of returning these children to a normal laryngeal and respiratory
function.
+++
Webs, Cysts,
and Laryngoceles
++
Partial or complete glottic webs can
occur with aberrant development of structures in and around the
laryngeal inlet in the embryo. Abnormal voice and, in more severe
disease, stridor and respiratory distress can be the presenting signs.
Tracheostomy can be lifesaving in the more complete glottic webs.
Because there is an association between glottic web and velocardiofacial
syndrome, children with glottic webs should have genetic consultation
and genetic testing for 22q11 gene deletions.
++
Congenital cysts of the larynx arise from the
mucus-secreting epithelium in the supraglottic region and occasionally
in the subglottic space. Presenting symptoms include stridor and
sometimes hoarseness. These must be distinguished from vallecular
cysts that, if large, seriously interfere with swallowing and breathing. Subglottic
cysts may be congenital, but they are usually secondary
to prolonged or traumatic intubation. In either case, the endoscopic
CO2 laser can be used to remove the cyst.
++
Laryngoceles are epithelium-lined diverticula
that originate from the laryngeal ventricle. They can present internally
in the larynx with airway obstruction or externally as a neck mass.
Total excision of the cyst by external approach is the treatment
of choice, but the endoscopic CO2 laser may be useful in
selected cases. Thyroglossal duct cysts can present at birth as
an obstructive lesion at the base of the tongue.
+++
Laryngotracheoesophageal
Defects
++
Incomplete formation of the tracheoesophageal septum can leave
abnormal connections between the food and air passages. Clefts range
from a slight deepening of the interarytenoid notch to a complete absence
of the tracheoesophageal septum to the carina. The conventional
classification system is shown in eFigure 371.1.
Symptoms may vary according to
the length of the cleft. The child with a significant cleft will
present with recurrent aspiration, failure to thrive, or life-threatening
respiratory events. Small clefts are often difficult to demonstrate
radiographically or endoscopically and require a high degree of
suspicion to be diagnosed early. Surgical repair is indicated for
all clefts with functional impairment. Extensive clefts are best
repaired using extracorporeal membrane oxygenation (ECMO) or cardiopulmonary
bypass to permit unhindered surgical access to the entire length
of the larynx, trachea, and esophagus.
++
++
The possible causes of vocal fold paralysis in children are presented
in Table 371-5. The symptoms of unilateral
vocal fold paralysis are often so mild that the disorder often goes
unnoticed. Unilateral recurrent laryngeal nerve paralysis results
in the affected fold assuming a midline or slightly abducted position,
and the cry is weak. The cry usually returns to near normal because
the unaffected vocal fold compensates for the paralyzed one and
because of synkinetic reinnervation of the affected vocal fold.
Aspiration of liquids may occur if the normal vocal fold fails to
compensate for the paralyzed one and there is incomplete laryngeal
closure during deglutition. On inspiration, the normal vocal fold
abducts completely to create an airway adequate for all except the
most strenuous exercise. Superior laryngeal nerve injury results
in paralysis of the cricothyroid muscle on the injured side. Decreased
tension of the vocal fold accounts for the slight decrease in vocal
range that is characteristic of superior laryngeal paralysis. Treatment
may be required for unilateral vocal fold paralysis. Options include
ansa-RLN reinnervation and laryngoplasty (surgical medialization
of the paralyzed fold by injection or implant) to improve the voice
or to decrease aspiration.
++
++
Bilateral recurrent laryngeal paralysis is usually characterized
by marked airway obstruction and a good voice; both vocal folds are paralyzed
in the midline or in a slightly abducted position. Management of
symptomatic bilateral vocal fold paralysis requires prompt airway
intervention, either intubation or tracheostomy, to relieve the
airway obstruction. If the cause of the vocal fold paralysis is
treatable (such as posterior craniotomy for Arnold-Chiari malformation)
or if it resolves (such as with Guillain-Barré syndrome),
the vocal folds may regain their mobility, permitting extubation
or decannulation. If the paralysis is permanent, several procedures
have been advocated to create an airway adequate to allow decannulation.
Partial arytenoidectomy or unilateral vocal fold lateralization
by either endoscopic or external methods allows one of the vocal
folds to be permanently lateralized. There is a trade-off of airway
for voice in this situation—the improvement in airway is
often offset by reduced volume of the voice.
+++
Inflammatory
and Infectious Disorders of the Larynx
++
Viral laryngitis is often a component of upper respiratory infection
(see also Chapter 241). Laryngeal manifestations
usually include a hoarse, raspy voice, which is related to edema
of the vocal folds, but airway obstruction is rare. Humidification,
throat gargles, and voice rest are recommended for symptomatic relief.
Laryngotracheobronchitis, or croup, is a common disorder of early
childhood that is potentially life-threatening.
+++
Laryngotracheobronchitis
(Croup)
++
Viral laryngotracheobronchitis is most prevalent from age 3 months
to 3 years and peaks during the second year of life, and it is more
common in boys than girls. Most cases occur in the late fall and early
winter, reflecting the epidemiological patterns of the various agents.
Human parainfluenza virus types I and II account for most cases
of croup in young children. Sporadic and sometimes severe cases
of croup may be associated with other types of human parainfluenza
virus, influenza virus types A and B, respiratory syncytial virus
(RSV), measles, and a variety of other viruses. RSV is a major cause
of lower respiratory tract infection in young children, and croup
is its least common clinical manifestation. However, because a high
percentage of young children admitted to the hospital with acute
lower respiratory tract disease have high RSV isolates, this pathogen
cannot be discounted as a cause of croup.
++
Viral upper respiratory tract infections usually affect the mucosa
of the nose and nasopharynx first and then spread to involve the
larynx and tracheobronchial tree. Under the mucosa of the subglottis of
the young child is a generous subepithelial connective tissue space
that permits submucosal edema formation with narrowing of the airway.
The barking cough and stridor characteristic of croup generally
result from edema of the subglottic airway. The cricoid cartilage
is a complete ring, so the airway is narrowest here, and swelling
cannot occur outward. Therefore, even minimal edema can cause airway
obstruction, with symptoms being more likely in young children,
because their small airway diameter increases resistance to airflow.
++
In croup, stridor is most common on inspiration because the negative
inspiratory pressure tends to collapse the already partially narrowed
extrathoracic structures. Biphasic stridor occurs if the subglottis is
extremely narrow. Copious secretions produced secondary to inflammation
will also clog the airway, producing secondary obstruction in an
already narrow region.
+++
Diagnosis and
Treatment
++
The differential diagnosis of viral laryngotracheitis includes
spasmodic croup, bacterial croup and tracheitis, retropharyngeal
abscess, angioneurotic edema, and foreign bodies of the aerodigestive
tract. The most important element in evaluating children with croup
is distinguishing those with croup from those with epiglottitis,
although this is far less a concern in regions where Haemophilus
influenzae vaccination has almost eliminated epiglottitis
(see below). Managing croup consists of supportive treatment with
cool mist. At home, this can be achieved by a cool mist vaporizer
or placing the child in a bathroom filled with steam from the shower
or by taking the child outdoors in the cool night air. In the hospital,
initial management consists of hydration, cool mist with or without
supplemental oxygen, and steroid medication. Racemic epinephrine
is reserved for severe cases.
++
Prospective, randomized studies have demonstrated that steroid
therapy decreases the length and severity of the respiratory symptoms
associated with viral croup. Dexamethasone is the preparation most frequently
used, in doses between 0.6 and 1.0 mg/kg. Many investigators
use a croup score, both for the initial triage of the child and
to evaluate response to medical therapy but the value of these scoring systems
in routine clinical pratice remains to be proven. Whatever method
is used, sound medical judgment is needed to predict the onset of
respiratory failure, hypoxia, and hypercarbia. Most infants improve
over 48 to 72 hours without further treatment, but some require
intervention for impending respiratory failure. Limited data suggests
that helium/oxygen mixtures (HELIOX) may have some benefit
in infants without high oxygen content requirements but with impending
respiratory failure. Intubation is rarely necessary, and if it is
required, the presence of an underlying congenital lesion such as
subglottic stenosis or a vascular ring should be considered. Recurrent
episodes of croup may occur in otherwise normal children, but a
suspicion of another possible airway lesion should be maintained,
especially in younger children.
++
Acute epiglottitis is an infection of the larynx with rapid swelling
of the epiglottis and increasing inspiratory difficulty. Since the
introduction of the Haemophilus B vaccine, this
disorder is an increasingly uncommon infection of the supraglottic
larynx. The management of epiglottitis is discussed in Chapter 263. H influenzae still remains the most common
bacterial infection of the larynx, especially in regions where vaccination
is unavailable. Bacterial infections by Streptococcus, Staphylococcus, and
others have also been reported as causes of supraglottic infection.
++
Diphtheria is an example of a bacterial infection that can involve
the larynx and other areas of the upper aerodigestive tract (see Chapter 261). Tuberculosis of the larynx can
occur and is usually associated with a generalized pulmonary infection.
++
In spasmodic croup, an otherwise healthy child wakes up in the
middle of the night with a barky cough and mild to severe inspiratory stridor.
The condition variously responds to humidification or exposure to
cold air. The next day, the child appears healthy, but the cyclic
episode repeats itself on two or three successive nights. The repetitive
nature of this problem and its variable response to therapy are
quite characteristic. The etiology is not understood. Absence of
any signs of upper respiratory tract infection separates this entity
from acute infectious croup and suggests an allergic origin. Gastroesophageal
reflux may be a factor in some children by causing a baseline airway
inflammation that, when challenged with a viral upper respiratory
infection, creates additional edema that causes significant airway
obstruction. Failure of typical therapies, especially in conjunction with
obstructive symptoms during allergic episodes, may be cause to suspect
a subglottic stenosis. Such a reduction of the already restricted
subglottic space may make an otherwise normal child unable to tolerate
even mild inflammation associated with allergic sensitivities.
++
The larynx is susceptible to the same allergens that affect other
parts of the upper aerodigestive tract. When the mucosa of the larynx
is involved, edema of the vocal cords results in a hoarse voice
and a dry, scratchy feeling in the throat. The larynx may also be
irritated by an allergic postnasal drip. Treatment of allergic manifestations
in the larynx includes avoiding the offending allergen, systemic antihistamines,
humidification, systemic or aerosol corticosteroids, and desensitization.
++
Angioedema consists of localized edema of rapid onset in response
to a variety of triggers, including infection, drugs (especially
angiotensin-converting enzyme inhibitors and aspirin), exercise,
allergens, insect bites, serum sickness, collagen vascular diseases,
and malignancy. It commonly affects the upper airway and can cause
life-threatening obstruction. Subcutaneous epinephrine (0.01 mL/kg
of 1:1000 concentration) provides rapid relief. A variety of antihistamines,
such as diphenhydramine, provide longer-term control. Occasionally,
systemic steroids are required to control the problem. Hereditary
angioneurotic edema is a rare disorder and is discussed in Chapter 189.
+++
Gastroesophageal
Reflux
++
Gastroesophageal reflux with passage of gastric contents into
the pharynx is normal in infants and young children. When the larynx’s
anatomy and physiology are normal, the refluxed gastric material never
enters the airway. When laryngeal anatomy is abnormal, as with a
laryngeal cleft, or if the normal protective reflexes are absent
because of neuromuscular disease, the gastric material can impinge on
laryngeal structures and may enter the airway. Even infrequent (such
as once every several days) exposure can cause laryngeal inflammation
and may aggravate many laryngeal and upper airway conditions in
infants and children. In children with chronic cough, oropharyngeal
dysphagia, vocal fold granuloma, airway obstruction, apnea, asthma,
recurrent croup, laryngomalacia, chronic laryngitis, and subglottic
stenosis, gastroesophageal reflux should be considered as an underlying
etiologic factor (see Chapter 394).
+++
Masses and Tumors
of the Larynx
++
Hoarseness can result from the formation of vocal fold nodules
as a result of persistent vocal misuse or abuse such as by shouting,
screaming, or singing. These masses occur at the junction of the
anterior and middle one third of the vocal cords, which is the point
of maximal vocal fold vibration. The size of the nodules and the
resultant hoarseness usually fluctuate, depending on the child’s
vocal use or abuse. It is important to diagnose the cause of hoarseness
in young children by performing a flexible laryngoscopy, especially
to rule out other causes, such as papilloma. Once the diagnosis
of benign vocal lesions is made, a period of observation is appropriate
in young children. In older children, if the problem persists, nodules
are best managed by voice and speech therapy. Occasionally, nodules that
have fibrosed from long-standing vocal abuse may not respond to
conservative management and will require microlaryngoscopic removal.
If the child continues with poor vocal habits, the nodules will
likely recur; therefore, speech therapy is an important adjunctive
therapy.
++
Although they are not considered true neoplasms, the wartlike
lesions from recurrent respiratory papillomatosis are often referred
to as the most common tumor of the larynx in children. The papilloma virus,
especially types 6 and 11, is the cause of the lesions, with a particular
predilection for the upper aerodigestive tract, especially the larynx.
The “juvenile” type of this disease usually makes
its presentation at 2 to 5 years of age, causing hoarseness and
marked airway obstruction in severe cases. The course of the disease
is characterized by multiple cycles of growth and regression. In
many cases, a spontaneous remission occurs, usually around puberty.
None of the recommended treatments—surgical excision, laser
excision, cryotherapy, ultrasound, interferon, or topical agents—has
been consistently shown to cure the disease. The goal in treating
these patients is to maintain a good voice and an unobstructed airway
by repeated functional excision of the papillomas. There is an incidence
of malignant transformation, making this a serious disease. The
effect of the human papillomavirus vaccine on this disease is unknown
but may reduce the occurrence of this difficult problem in the future.
++
These lesions may occur in the larynx, primarily in the subglottic
area. They are often associated with other cutaneous hemangiomas
but also occur as isolated lesions. With crying or straining, these lesions
increase in size and cause significant airway obstruction. They
appear as asymmetric masses on anteroposterior neck radiography,
but the diagnosis must usually be confirmed by microlaryngoscopy.
Because many hemangiomas of infancy tend to involute after a period
of growth during the first year, close observation is the initial
treatment of choice. If obstructive symptoms require more aggressive
treatment, high-dose steroid therapy can be instituted to limit
the hemangioma’s growth. If the lesion fails to decrease
in size, options include endoscopic or open surgical excision or
tracheostomy. Recent experience suggests that the CO2 laser
or photoangiolytic laser such as KTP (potassium-titanyl-phosphate)
laser can partially remove hemangiomas without airway obstruction
or hemorrhage. Increasingly, removing the hemangiomas by external
surgery followed by brief intubation is the most effective and permanent
solution to the problem without impacting the voice.
+++
Approach to
the Child with Dysphonia
++
The approach to the child with dysphonia depends on the child’s
age and whether there is accompanying airway compromise. In very
young children—especially those who have had surgical procedures such
as a patent ductus arteriosus (PDA) ligation, other cardiac surgery,
neurological compromise, or prolonged intubation—a paralyzed
true vocal fold should be suspected. Dysphonia may also be the first
presenting symptom in a child with respiratory papillomatosis. Young
children with dysphonia that persists more than a short time warrant
consultation for evaluation and flexible laryngoscopy. In older
children, the overwhelming majority will have benign vocal fold
nodules. However, other pathology that requires more urgent intervention
is possible. Consultation by an otolaryngologist should be considered
for children who have consistent, rather than intermittent dysphonia,
when the severity of dysphonia is progressively worsening, or in
children with complete aphonia. Other concerning associated symptoms
include swallowing difficulties, pain, respiratory difficulties,
a history of trauma, or other systemic conditions such as rheumatoid
arthritis. If there is a history of recent intubation or if the
dysphonia persists for greater than several months, consultation
should also be considered. A growing number of tertiary pediatric
centers provide expertise in voice centers or clinics with sophisticated
diagnostic tools geared toward children. In addition, these centers
generally provide an interdisciplinary team that includes a speech
therapist and specialized nursing care to allow for improved therapeutic
interventions for children who have laryngeal pathology.
+++
Laryngotracheal Trauma
++
Blunt or penetrating injuries may occur with sports or motor
vehicle accidents. These injuries may result in mucosal laceration,
laryngeal hematomas, vocal fold paralysis, or fractures of the larynx. Patients
present with various degrees of neck pain, hoarseness, hemoptysis,
and airway obstruction. Physical examination may reveal anterior
neck tenderness, crepitance, and absence of the normal prominence
of the thyroid cartilage. Proper treatment requires recognizing
the nature of the injury and protecting the airway.
++
Endotracheal intubation can cause mucosal lacerations, granulomas
of the vocal folds, dislocation of the arytenoid cartilage, and
subglottic stenosis. Mucosal ulcerations and pressure necrosis can
occur as the mucosa is compressed by the pressure of a tight-fitting
endotracheal tube against the unyielding cricoid cartilage surrounding
the subglottic space; resultant chondritis or mucosal fibrosis can
produce mature scar tissue that significantly narrows the subglottic
lumen. A congenital smaller-than-normal airway, a large endotracheal
tube, inadequate fixation of the tube, prolonged intubation, mechanical
ventilation, multiple intubations, infection, and cuffed endotracheal
tubes all increase the individual’s risk of developing
subglottic stenosis. Treatment is the same as that described for
subglottic stenosis of congenital origin, relying mainly on open
laryngotracheal reconstruction techniques. For mild to moderate
degrees of stenosis, endoscopic dilation and topical mitomycin application
is also an appropriate option.
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Foreign-Body Aspiration
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Foreign body aspiration is discussed in detail in Chapter 118.
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There are four major indications for long-term tracheotomy in
children: airway obstruction, ventilatory support, severe obstructive
sleep apnea, and pulmonary toilet. A detailed discussion of tracheostomy management
is provided in Chapter 124.