The Child with Stridor 2:
Chronic Stridor
Chris Kingsnorth
Before We Begin
Overview
• Definition of stridor
• Differential diagnoses:
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Croup
Acute epiglottitis
Bacterial tracheitis
Foreign body aspiration
Laryngomalacia
Subglottic stenosis
Stridor: Recap
“…High-pitched breath sound
resulting from turbulent air flow
secondary to narrowing in the upper
airway…”
Stridor: Recap
• Timing of stridor suggests the level of
narrowing:
• Inspiratory: Laryngeal region
• Expiratory: Tracheobronchial region
• Biphasic: Subglottic/glottic region
Differential Diagnoses
Croup
Acute
Acute epiglottitis
Foreign body
Laryngomalacia
Chronic
Subglottic stenosis
History, Examination and
Investigations (Overview)
See ‘The Child with Stridor 1: Acute Stridor’
Chronic Stridor:
Laryngomalacia
Laryngomalacia: Epidemiology
• A.k.a ‘floppy larynx’
• Most common cause of stridor overall
• Most common congenital laryngeal
abnormality (60% of all cases)
• M=F
Laryngomalacia: Pathophysiology
• May affect epiglottis, arytenoid cartilages or
both
• Epiglottis: Elongated and ‘omega-shaped’ Ω
• Arytenoid cartilages: Enlarged
• In both cases, cartilage floppy and structures
prolapse over larynx during inspiration
Laryngomalacia: Classification
Type 1
Aryepiglottic folds are tightened/ foreshortened
Type 2
Redundant soft tissue in any area of supraglottic region
Type 3
Associated with other disorders
(e.g. neuromuscular disease, gastro-oesophageal reflux)
Laryngomalacia: Clinical Features
• Noisy respiration and inspiratory stridor
develops within weeks of birth (often absent
at birth; typically begins at 4-6 wks)
• Worse when supine, distressed or feeding
• Cry normal (distinguishes from abnormality
around vocal cords)
• Otherwise happy, healthy babies
10 week old baby with laryngomalacia. Note that stridor is
inspiratory only.
Laryngomalacia: Investigations
• Not required if Hx clear
and baby well
• Laryngoscopy and
bronchoscopy most useful
for Dx
• Fluoroscopy
Laryngomalacia on laryngoscopy. Note curled ‘omega-shaped’
epiglottis
Laryngomalacia: Prognosis
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Increase in severity of Sx during first 8 months
Peak at 9-12 months
Resolution thereafter
99% of cases resolve spontaneously
Laryngomalacia: Management
• Pulse oximetry
• Supportive care and regular review
• Monitor for signs of OSA (cyanosis, apnoeas,
respiratory distress during sleep)  sleep
study
Laryngomalacia: Management
• Surgical Mx considered in severe cases (e.g.
FTT, respiratory failure, OSA, pulmonary HTN,
cor pulmonale)
• Options include:
• Tracheotomy
• Supraglottoplasty (tightening of support
structures and removal of excess tissue)
• Laser epiglottopexy
Chronic Stridor:
Subglottic Stenosis
Subglottic Stenosis: Epidemiology
• Incidence unknown
• Can be congenital or acquired:
Congenital
Malformation of cricoid cartilage
Acquired
Most commonly secondary to trauma (esp.
intubation) or infection
Subglottic Stenosis:
Clinical Features
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Biphasic stridor
Respiratory distress
Recurrent croup
Gastro-oesophageal reflux
Children with severe subglottic stenosis at birth
may require intubation +/- tracheostomy
Subglottic Stenosis:
Investigation and Grading
• Direct
laryngoscopy and
bronchoscopy
• Fluoroscopy
Grade 3 + 4 = severe
Subglottic Stenosis: Management
Grade 1
Monitor; intervention often not required
Grade 2
Balloon dilatation
Grade 3
Tracheostomy, then laryngotracheal reconstruction
(LTR) or partial cricotracheal resection (CTR)
Grade 4
Rx gastro-oesophageal reflux if present (prior to surgical intervention)
Subglottic Stenosis: Prognosis
• Dependent on grade
• In severe subglottic stenosis, success rate of
surgical intervention 80-90%
What Now?
• Download slides/ notes pages
• Online MCQ: https://www.goconqr.com/enGB/p/3962527-The-Child-with-Stridor-2-Chronic-quizzes
• Request a Podcast/ ask a question
References
• Stridor sound clip:
https://en.wikipedia.org/wiki/File:Stridor_NP_
OGG_2.ogg
• Laryngoscopy images:
https://www.youtube.com/watch?v=6xOHYOu
iSH0
• Subglottic stenosis grading:
http://www.chop.edu/conditionsdiseases/subglotticstenosis/about#.Vjt8WPnhDIU