Treatment of Pediatric Airway Disorders: Beyond Tracheostomy

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Treatment of Pediatric
Airway Disorders:
Beyond Tracheostomy
Meredith N. Merz, M.D.
Nationwide Children’s Hospital
Department of Pediatric Otolaryngology
April 6, 2011
Objectives
1. Identify the most common causes of stridor in the
pediatric population.
2. Discuss diagnostic techniques in a child with stridor.
3. Understand the pathogenesis of acquired subglottic
stenosis and the difference between congenital and
acquired stenosis.
4. Discuss treatment options for the most common
airway disorders in children.
Laryngeal Function
• Three Main Functions:
1. Acts as an airway from pharynx
into trachea and lungs
2. Instrument of phonation
3. Protects the lower airways
• Closure of glottis during swallowing
• Epiglottis folds posteriorly over
glottis
• Cough
Infant Larynx
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Larynx is more rostral
Epiglottis apposes the soft palate
Hyoid bone is impacted on thyroid cartilage
Vocal cords are oriented transversely
Epiglottis is short and curled in on itself
Arytenoids are anteriorly oriented and involve half
the length of the vocal folds
Infant Larynx
Bosma JF. Anatomy of the Infant Head. Baltimore, Johns Hopkins University
Press, 1986, pp 366-367.
Stridor
• Harsh sound caused by turbulent airflow
• Implies partial airway obstruction
• Location of lesion determines character of stridor
o Supraglottic
o Extrathoracic
o Intrathoracic
Physics Review…
• Poiseuille’s Law
Q = [πd4 (P1-P2)] / 128ν
Flow within a system is related to the radius of the tube to
the fourth power
Resistance is related to the inverse of the radius to the
fourth power
• Bernouilli’s Law:
W = PAv
As velocity increases through a constant area the pressure
on the wall of the lumen decreases
A region of anatomic narrowing is predisposed to collapse
further with increased turbulent airflow
Effect of Airway Narrowing
Localizing Stridor
• Supraglottic obstruction
o With inspiration the loosely supported supraglottic structures
collapse. Increased turbulence causes increased constriction
o Stridor is inspiratory and high pitched
• Extrathoracic obstruction
o Airway is affected equally by inspiration and expiration
o Stridor is biphasic, often accompanied by increased work of breathing
• Intrathoracic obstruction
o Relative positive pressures of expiratory forces narrow the airway
lumen, resulting in increased constriction
o Stridor is expiratory and “musical”; Wheeze
Airway Evaluation- History
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Age at onset
Onset: acute, chronic, progressive
Prior respiratory problems
Birth history
Prior intubation
GERD symptoms
Wheezing episodes
Feeding problems:
o FTT, weight gain
• Choking episodes
• Aggravating factors
Airway EvaluationInitial Examination
• Inspection
o General appearance and position, color, retractions, level of
consciousness
• Auscultation
o Mouth/Nose, Neck and Chest
• Repositioning
o Prone/Supine, lateral, jaw thrust
• Is there acute distress?
o
o
o
o
o
Nasal flaring
Tachypnea
Cyanosis
Retractions
Tripod position
Flexible Nasopharyngoscopy
• Gold Standard for
office evaluation
• Assess nares/ choanae
• Assess adenoid and
lingual tonsil
• Assess laryngeal
structures
• Assess TVC mobility
• Drawback:
Poor for assessing
subglottic structures
Radiologic Evaluation
• Plain films have limited utility
o PA/ Lateral Neck
• Airway Fluoroscopy
o Evaluate the dynamics of
respiration
• Inspiratory/ Expiratory CT Scan
Rigid Laryngoscopy and Bronchoscopy
• Indications:
o To establish diagnosis or evaluate for synchronous lesions
(after flexible exam)
o Severe or progressive stridor
o Cyanosis or apnea concerns
o Radiologic abnormalities
o Parental or physician anxiety
o Foreign body evaluation
Rigid Laryngosocpy
Rigid Bronchoscopy
Congenital Disorders of the Larynx
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Laryngomalacia
Congenital subglottic stenosis
Vocal cord paralysis
All Others:
o
o
o
o
60%
16%
13%
7%
Congenital laryngeal web
Laryngocele and Saccular cyst
Laryngeal/ Laryngotrachealesophogeal Cleft
Vascular lesions
Holinger, LD. Etiology of Stridor in the Newborn, Infant, and Child. Annals
of ORL, 1980; 89: 397-400.
Laryngomalacia
• Most common cause of stridor in infants
• Presentation
o Staccato/ Coarse inspiratory stridor
o Worse with exertion, feeding, crying
o Noisy breathing generally begins at about 2-4 weeks of age
• Office Evaluation
o Character of stridor
o Positional changes
o Flexible nasopharyngoscopy
Laryngomalacia
• Endoscopic appearance
o Omega epiglottis
o Foreshortenend aryepiglottic folds
o Cuneiform and corniculate prolapse
Laryngomalacia Classification
Type I
Type II
Type IV
Type III
Type V
Kay DJ, Goldsmith AJ. Laryngomalacia: A Classification System and Surgical
Treatment Strategy. Ear Nose Throat J. 2006 May;85(5):328-31, 336.
Laryngomalacia
• Vast majority are mild
• Parental reassurance & education
o Transient worsening, gradual improvement
o Weight gain issues
o GERD issues- Consider GERD treatment if there is evidence
on endoscopy
Severe Laryngomalacia
• Respiratory difficulty
o Apnea/ Cyanosis/ ALTE
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Feeding difficulty
Failure to thrive
Uncontrolled GERD
Sleep apnea
CNS abnormalities
Severe Laryngomalacia
Surgical Treatment
• Supraglottoplasty- Aryepiglottic fold division +/- Excision of
corniculate cartilages
Severe Laryngomalacia
Epiglottic Procedures
• Epiglottic Procedures:
o Epiglottoplasty- Excision of a
V-shaped wedge of tissue
from the epiglottis
o Epiglottopexy- Epiglottis is
pexied to the base of tongue
with stitch/ laser
Whymark AD, Clement WA, Kubba H, Geddes N. Laser Epiglottopexy for
Laryngomalacia. Archives of Otolaryngology Head and Neck Surgery, 2006;
132: 978-982.
Vocal Cord Paralysis
• Bilateral: Airway issues,
Aspiration issues
o Expectant (can take years
to resolve)
o Close monitoring of O2 sat,
apnea, weight gain
o Tracheotomy
o Posterior laryngeal
expansion
o Botox (for spastic paralysis)
o Cordotomy
o Arytenoidectomy
o Re-innervation procedures
• Unilateral: Voice Issues,
Aspiration Issues
o Observation
o Vocal Cord Injection
o Thyroplasty
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