FIXING THE PEDIATRIC AIRWAY
Educational Objectives
| The goal of this program is to improve the management of airway problems in children. After hearing and assimilating this
program, the clinician will be better able to:
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 | 1. Assess the severity of stridor in infants.
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| 2. Diagnose laryngomalacia, and other causes of stridor.
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| 3. Grade laryngeal (subglottic) stenosis and treat using endoscopic or open techniques.
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| 4. Describe the presentation and classification of congenital tracheal stenosis and use slide tracheoplasty to repair
symptomatic tracheal rings.
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| 5. Classify and treat laryngeal clefts by endoscopic or open techniques.
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Faculty Disclosure
In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning
committee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts
of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health
care and not a proprietary business or commercial interest. For this program, the following has been disclosed: Dr. Muntz
has received honorariums from Abbott Laboratories. Drs. Chang and Koltai and the planning committee reported nothing to
disclose.
Acknowledgements
Drs. Chang and Koltai were recorded at Pediatric Otolaryngology Update 2008, presented by the Department of
Otolaryngology–Head and Neck Surgery, Stanford University School of Medicine, and Lucile Packard Children’s
Hospital at Stanford University, and sponsored by Stanford University School of Medicine. Dr. Muntz addressed
Heads Up: Pediatric HEENT Conference, held March 13-14, 2008, in Napa Valley, CA, and sponsored by Kaiser
Permanente Thrive, Sutter Medical Center, Sacramento, and University of California, Davis, Health System Office of
Continuing Education and Department of Pediatrics. The Audio-Digest Foundation thanks the speakers and the sponsors
for their cooperation in the production of this program.
| INFANT STRIDOR: AN OVERVIEW —Harlan Muntz, MD, Professor of Otolaryngology–Head and Neck Surgery, University
of Utah School of Medicine, and Primary Children’s Medical Center, Salt Lake City, UT
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| Newborn with stridor: assessing severity most important; evaluate feeding (if feeding takes >30 min, “something is
wrong”); determine whether caloric intake adequate; child with significant feeding difficulties at risk; determine whether
stridor inspiratory, expiratory, or both; pearl—to avoid missing quieter component of biphasic stridor, remove head of
stethoscope and listen with stethoscope right next to larynx; inspiratory stridor—without expiratory component, typically
supraglottic; biphasic stridor—consider fixed lesion or multiple lesions; subglottic stenosis (SGS)—inspiratory
noise louder than expiratory, even with fixed lesion, because flow rate across narrow area greater during inspiration; normal
respiratory cycle one-third inspiration, two-thirds expiration; consequently, flow rate during expiration half as much
and, therefore, quieter; fixed intrathoracic lesion (eg, tracheal stenosis)—stridor biphasic, but expiratory noise greater
because of collapse due to increased intrathoracic pressure; tracheomalacia—sometimes only expiratory stridor heard and
misdiagnosed as asthma
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| Differential diagnosis: large tongue; lymphangioma or hemangioma; lingual thyroid; vallecular cyst or pseudocyst;
laryngomalacia
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| Laryngomalacia: most common laryngeal abnormality (75% of children presenting with stridor); typically, stridor intermittent
and low pitched; often not immediately apparent at birth, but worsens over weeks; rarely diagnosed at >1 mo
of age, except in some children with cerebral palsy; symptoms usually worst at <6 mo of age, then resolve by 18 to 24
mo of age; stridor—typically exacerbated by exertion, eg, crying, feeding, agitation, lying on back; exacerbations
atypical in some children, eg, during sleep; in most children, laryngeal collapse occurs at end of respiratory cycle, so
most do well; epiglottis—often appears posteriorly placed, due to shortening of aryepiglottic fold; in epiglottic laryngomalacia,
epiglottis flaps back over airway and blocks it
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| Diagnosis: difficult to make only on basis of history and physical examination; outpatient flexible laryngoscopy often
makes diagnosis, and if child has classic laryngomalacia, no further work-up needed; if stridor has expiratory component,
order airway film to look for subglottic stenosis; direct laryngoscopy and bronchoscopy—necessary in presence
of failure to thrive, dysphagia, cyanosis, or other sign that may indicate second lesion or laryngomalacia severe
enough to warrant treatment, eg, supraglottoplasty
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| Laryngeal atresia: life threatening; child typically also has tracheoesophageal (TE) fistula, so continuous positive airway
pressure (CPAP) improves breathing; intubation usually results in esophageal intubation; laryngeal webs—thick
web causes severe airway obstruction; with thin web, small amount of stridor; supraglottic webs may present with
hoarseness rather than stridor
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| Other causes of stridor: laryngoceles and cysts—near vocal folds; present with muffled or inaudible cry; often accompanied
by dysphagia; respiratory distress; laryngeal clefts—difficult to see on flexible endoscopy; can be repaired;
true vocal cord (TVC) paralysis—more common in neurologic conditions, eg, Chiari malformation; unilateral left-sided
TVC paralysis may indicate undiagnosed cardiac disease or may be complication of ligation of patent ductus arteriosus; also
seen with hypoplastic heart and aortic malformations; symptoms often not helpful for diagnosis, but include weak breathy
cry, cough, and stridor (often not predominant); signs include patchy atelectasis; tracheomalacia—rare; seen with vascular
anomalies and with masses; in tracheomalacia of prematurity, tracheal rings like “C,” rather than like horseshoe; pressure
from vascular ring may push posterior trachea anteriorly; papilloma—usually presents at ≈3 mo of age; progressive stridor;
often misdiagnosed; benign, but may cause severe airway obstruction
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| LARYNGEAL (SUBGLOTTIC) STENOSIS— Kay W. Chang, MD, Associate Professor of Otolaryngology, Stanford
University School of Medicine, Palo Alto, CA
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| Congenital SGS: third most common cause of stridor in infants; defined as narrowing of airway in absence of trauma (eg,
intubation); in normal full-term newborn, diameter of larynx 5 mm; airway <4 mm in full-term or <3 mm in premature infant
considered SGS; Cotton-Myer grading system—grade 1 (≤50% obstruction); grade 2 (50%-70% obstruction); grade
3 (≤99% obstruction); grade 4 (complete obstruction); grade 1 rarely requires intervention beyond supportive therapy, and
mild symptoms usually resolve with growth; point—area varies by square of diameter, so reduction of airway from 5 mm
to 3.5 mm represents >50% reduction; membranous type—usually acquired; circumferential, soft, and usually dilatable;
thickened mucosal lining with increased fibrous connective tissue layer, hyperplasia of mucus glands, ductal cysts, and granulation
tissue; cartilaginous type—congenital; variable appearance; normal-shaped small larynx; abnormal shapes include
elliptical cricoid with prominent lateral shelves (most common); partial or complete cricoid cleft; other shapes and configurations
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| Symptoms: inspiratory stridor that becomes biphasic as severity of stenosis increases; mild to moderate stenosis may be
asymptomatic until upper respiratory infection (URI) results in subglottic edema; as stenosis worsens, retractions observed,
and severe obstruction in neonatal period can result in intubation, changing classification from congenital to acquired;
90% of acquired SGS result of intubation
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| Diagnostic evaluation: awake flexible laryngoscopy shows whether stenosis severe, and allows observation of vocal
cord motion; direct laryngoscopy and bronchoscopy in operating room (OR; gold standard) allows sizing and thorough
assessment of airway for synchronous lesions and abnormalities; rule out gastroesophageal reflux (common); chest x-ray
to document lung status (may also reveal tracheal abnormalities); sizing—done by determining largest endotracheal tube
(ETT) that allows air leak of 10 to 25 cm H2 O; ability to pass 3.5-mm ETT indicates 0% obstruction in infant ≤3 mo of
age (ETT with inner diameter of 3.5 mm has outer diameter of 5 mm); if only 3.0 mm ETT passable in 0- to 3-mo-old infant,
26% obstruction (grade 1); if only 3.0-mm ETT passable in 9-mo-old, 53% obstruction (grade 2)
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| Treatment: medical and supportive measures (eg, steroids, anti-reflux therapy, humidified oxygen) sufficient in many
patients with grade-1 SGS
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| Endoscopic approaches: for grade-1 lesions when patient not doing well, and for some grade-2 lesions; risk factors for
failure—previous failed endoscopic procedure; thick circumferential narrowing >1 cm in vertical dimension; involvement
of posterior commissure; loss of cartilaginous framework; exposure of perichondrium and cartilage (predisposes
to fibrosis); dilation—works well with short soft immature stenosis; ineffective with cartilaginous or mature stenosis,
and epithelial injury may worsen stenosis; speaker dilates with same type of balloon as used for sinuplasty; CO2 laser
techniques—avoid treating >30% of circumference, as this increases risk for further stenosis; use when SGS thin;
may require sequential surgeries; mitomycin C helpful in preventing fibrosis after procedure; speaker uses 0.4 mg/mL
applied via cotton pledget for 3 to 5 min after laser use; mitomycin C also used after balloon dilation
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| Open approaches: anterior laryngotracheal decompression (anterior cricoid split)—introduced in 1980 as alternative
to tracheotomy in premature infants with SGS who fail extubation; literature shows success in 66% to 78% of
cases; more recent literature shows 71.4% success from 1989 to 1995, but only 41.2% success from 1996 to 2005,
probably due to change in characteristics of neonatal population (more neurologic, respiratory, and cardiac comorbidities
and longer duration of intubation); laryngeal expansion procedures—typically, single-stage laryngotracheal reconstruction
(LTR) with anterior cartilage graft; most amenable to grade 2 and grade 3 lesions; grafts from, eg, thyroid
ala, auricular cartilage, costochondral cartilage; contraindications include low weight, inadequately controlled gastroesophageal
reflux, and need for ventilatory support; pearl—to maximize success in child with history of bronchopulmonary
dysplasia, child should have full season without hospitalization for respiratory illness before procedure done;
grade-4 lesions—often require 2 procedures with period of stenting; posterior as well as anterior grafts needed; in severe
cases, 4-quadrant cricoid division required; rib cartilage grafts—used when larger thicker grafts necessary; can
be designed with flange to prevent collapse into airway
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| Success rates for LTR: success defined as avoidance of tracheotomy or successful decannulation of patient with tracheotomy;
grade 2—single-stage procedures, 81% to 88% success; if second procedure done, success rate increased to 97%;
grade 3—slightly lower success rates than for grade 2; grade 4—37% to 50% success rate; even with multiple procedures,
rate 72%
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| Cricotracheal resection (CTR): has >90% success rate with grade-4 lesions in single procedure; involves resection
of anterior cricoid plus any narrowed upper tracheal rings and primary reanastomosis to thyroid cartilage and posterior
cricoid; in 2005 report on 100 CTRs, 94% decannulation rate achieved in patients with severe SGS (mean age of patients
6.1 yr); another 2005 series of 17 patients with average age of 14.6 mo reported 94% decannulation rate with 4 additional
CO2 laser treatments and no reintubations
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| CONGENITAL TRACHEAL STENOSIS —Peter J. Koltai, MD, Professor of Otolaryngology and Pediatrics, Department
of Otolaryngology–Head and Neck Surgery, Chief, Division of Pediatric Otolaryngology, and Director, Pediatric Otolaryngology
Fellowship, Stanford University School of Medicine, Palo Alto
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| Presentation: biphasic stridor most common (“washer machine breathing”; due to sticking of mucus at site of stenosis);
brassy barky seal-like cough; retractions; pursing of lips to achieve positive end-expiratory pressure (PEEP); hyperextension
of neck in effort to align orotracheal axis to facilitate breathing; sleep apnea often primary presentation; cyanosis (occasionally);
failure to thrive common presentation among patients with Down syndrome; dying spells, ie, child takes deep breath
then loses consciousness because of inability to expel air; by definition, present at birth, but often presents at ≈1 mo of age
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| Diagnosis: fiberoptic laryngoscopy; soft tissue x-rays (high KV Cincinnati view); computed tomography (CT) allows imaging
and measurement of airway; magnetic resonance imaging (MRI) helpful in acquired stenosis; esophagoscopy useful
in children with esophageal rings; visual examination by flexible bronchoscopy best diagnostic procedure
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| Classification of congenital tracheal stenosis (CTS): extrinsic or intrinsic (compression coming from outside or
within trachea); long or short; intrinsic short segment—includes tracheal web; rare; intrinsic long segment—tracheal
agenesis (rare); tracheomalacia
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| Tracheomalacia: flaccid tracheal cartilages; ratio of trachealis muscle to cartilage 2:1 (normal 4:1), causing diminished
anterior to posterior (AP) diameter (more prone to collapse); type 1—intrinsic to trachea and not associated with other
congenital anomaly; secondary type 1—associated with another tracheal anomaly, typically, TE fistula; type 2—
extrinsic compression of trachea, usually by vascular ring
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| Management: observation as child outgrows problem; positioning; control of gastroesophageal reflux; bilevel positive
airway pressure (BiPAP) to keep airway open; gastrostomy; Nissen procedure; tracheotomy until trachea matures;
stenting (may worsen problem as stent incorporated into wall; possibility of infection)
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| Tracheal rings: intrinsic long-segment stenosis; may have complete stenosis along entire length; focal funnel-like stenosis
as diameter goes from normal in proximal trachea to abnormal in distal trachea and more narrowed area just above
carina; management—observation; tracheotomy; resection; slide tracheoplasty
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| Slide tracheoplasty: currently most common management; involves elevating trachea off of esophagus, and splitting trachea;
posterior incision on proximal segment and anterior incision on distal segment; slide segments together, enlarging
diameter 4-fold while shortening length of trachea half-fold; anastomosis produces figure-8 shape
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| Vascular rings: innominate artery compression most common; symptoms benign; summated problem, ie, if other airway
issues, ring may be less benign
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| LARYNGEAL CLEFTS— Dr. Koltai
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| Definition: midline defect in posterior larynx; variable length; rare (1 in 10,000 births), with slight male predominance;
one-third have polyhydramnios, many syndrome-associated, and most have concurrent anomalies
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| Classification: type 1 (supraglottic)—defects of posterior larynx down to level of vocal cords but above cricoid cartilage;
type 2 (cricoid)—involve all or part of cricoid (defect in posterior lamina of cricoid); type 3 (cricotracheal)—
extend below cricoid into trachea above thoracic inlet; type 4 (complete)—extend through cricoid to variable distance
into trachea below thoracic inlet
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| Presentation: depends on length of cleft; symptoms may be nonspecific and range from trivial to life threatening; respiratory
distress during feeding; recurrent pneumonia; dysphonic cry; when symptoms present at birth, difficult to keep ET
tube in place (repeatedly displaced into esophagus); differential diagnosis—any lesion that causes cyanosis and aspiration
with feeding; includes TE fistula, cricopharyngeal achalasia, neurodevelopmental disability, and choanal atresia
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| Diagnosis: AP and lateral x-ray of chest; barium swallow most important (shows leak and penetration of airway; contrast
seen going into lungs); endoscopy gold standard; fiberoptic examination or direct laryngoscopy in OR under general anesthesia
with spontaneous ventilation; defect easy to miss (use right-angle probe)
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| Associated anomalies: Opitz or G syndrome—genetically heterogeneous X-linked recessive disorders or autosomal
dominant abnormalities; multiple midline defects, including absent corpus callosum, hypertelorism, heart defects, and
hypospadias; other defects—vertebral, anal, cardiac defects, tracheal, esophageal malformations, renal dysfunction,
limb deformities (VATER/VACTERL associations); multiorgan problems increase complexity of care and require team
effort
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| Treatment: depends on type and degree of aspiration; if no aspiration present, no intervention needed; minimal aspiration
managed by thickening feed; frank aspiration requires endoscopic closure; endoscopic technique (type 1 cleft)—
roughen mucosa on cleft, then sew closed from distal to proximal, one layer on internal aspect of larynx and second layer
on posterior aspect; 0.5 hr per suture, ≈4 sutures per case; type 2 cleft—generally done through laryngotomy; speaker
has successfully used endoscopic technique; roughen edges of cleft and do posterior closure of esophageal mucosa; tibial
perichondrium graft may be interposed in muscle between esophagus and larynx before laryngeal closure; open repair—
standard for types 3 and 4
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Suggested Reading
Beierlein W et al: Variations in the technique of slide tracheoplasty to repair complex forms of long-segment congenital
tracheal stenoses. Ann Thorac Surg 82:1540, 2006; Conlon BJ et al: The G syndrome/Opitz oculo-genital-laryngeal
syndrome/ Opitz BBB/G syndrome/Opitz-Frias syndrome. J Laryngol Otol 109:244, 1995; Durden F et al: Balloon
laryngoplasty as a primary treatment for subglottic stenosis. Arch Otolaryngol Head Neck Surg 133:772, 2007; Garabedian
EN et al: Cricotracheal resection in children weighing less than 10 kg. Arch Otolaryngol Head Neck Surg 131:505,
2005; Hartnick CJ et al: Surgery for pediatric subglottic stenosis: disease-specific outcomes. Ann Otol Rhinol Laryngol
110:1109, 2001; Jaquet Y et al: Partial cricotracheal resection for pediatric subglottic stenosis: long-term outcome
in 57 patients. J Thorac Cardiovasc Surg 130:726, 2005; Khariwala SS et al: Laryngotracheal consequences of pediatric
cardiac surgery. Arch Otolaryngol Head Neck Surg 131:336, 2005; Koltai PJ et al: Anterior and posterior cartilage
graft dimensions in successful laryngotracheal reconstruction. Arch Otolaryngol Head Neck Surg 132:631, 2006;
Kubba H et al: Techniques and outcomes of laryngeal cleft repair: an update to the Great Ormond Street Hospital series.
Ann Otol Rhinol Laryngol 114:309, 2005; Manning PB et al: Slide tracheoplasty in infants and children: risk factors
for prolonged postoperative ventilatory support. Ann Thorac Surg 85:1187, 2008; Manning SC et al: Laryngeal anatomic
differences in pediatric patients with severe laryngomalacia. Arch Otolaryngol Head Neck Surg 131:340, 2005;
Moukheiber AK et al: Repair of a type IV laryngotracheoesophageal cleft with cardiopulmonary bypass. Ann Otol
Rhinol Laryngol 111:1076, 2002; Myer CM 3rd et al: Proposed grading system for subglottic stenosis based on endotracheal
tube sizes. Ann Otol Rhinol Laryngol 103:319, 1994; Rahbar R et al: The presentation and management of laryngeal
cleft: a 10-year experience. Arch Otolaryngol Head Neck Surg 132:1335, 2006; Rutter MJ et al:
Nonoperative management of complete tracheal rings. Arch Otolaryngol Head Neck Surg 130:450, 2004; Sivan Y et
al: Diagnosis of laryngomalacia by fiberoptic endoscopy: awake compared with anesthesia-aided technique. Chest
130:1412, 2006; Smith JL 2nd et al: State-dependent laryngomalacia in sleeping children. Ann Otol Rhinol Laryngol
114:111, 2005; Zoumalan R et al: Etiology of stridor in infants. Ann Otol Rhinol Laryngol 116:329, 2007.
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