Stridor is a noisy, high-pitched breathing sound caused by upper airway obstruction. It is common in infants due to their small larynx size and loose tissues. The relationship of stridor to inspiration and expiration can provide clues to its cause. Acute stridor is usually due to inflammation and edema causing supraglottic or subglottic obstruction. Common causes include croup, epiglottitis, and infections. Chronic stridor may be due to congenital abnormalities, neurogenic issues, or tumors. Evaluation involves history, examination, and endoscopy. Management depends on the specific cause but may include antibiotics, steroids, intubation, or surgery.

1. LAKSHMI SASIKANTH
3rd year MBBS
STRIDOR

2. WHAT IS STRIDOR ???
 An excessively noisy , musical breathing due to upper airway
obstruction
 Its accompanied by hoarseness , brassy cough , dyspnea ,
chest retractions & restlessness
 Stridor is frequent in infants becoz :
 Small size of larynx
 Loose subcutaneous connective tissue around glottis region
 Rigid cricoid cartilage encircling the subglottic zone
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3. Relationship of stridor to the respiratory cycle often provides a clue to its
etiology :
INSPIRATORY
EXPIRATORY
BIPHASIC
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5. ACUTE STRIDOR
 Acute upper airway obstruction occurring in the region of
glottis which is produced by inflammation & oedema
 Maybe life threatening
 Obstruction can be
• Supraglottic as in epiglottitis
• subglottic as in infectious croup
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6. CHRONIC STRIDOR
Congenital laryngeal stridor
Congenital laryngeal or
tracheal stenosis or web
Laryngeal cyst or neoplasm
Neurogenic stridor Extrinsic obstruction
Miscellaneous causes:
Hydrochephalus, Downs,
micrognathia & glossoptosis ,
macroglossia &
diaphragmatic hernia
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7. INFECTIONS
 CROUP
 The term croup is used for used for a variety of conditions in
which a peculiar brassy cough is the main presenting feature
 The diseases include
 ACUTE EPIGLOTTITIS
 LARYNGITIS
 LARYNGOTRACHEOBRONCHITIS
 SPASMODIC LARYNGITIS
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8. EPIGLOTTITIS
• H.Influenzae type B – MC cause
• Starts with a minor URTI that progresses
rapidly within few hours
• High grade fever & dysphagia
• Tripod position , toxic appearing & drooling
• Frequent cough is absent
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10. LARYNGITIS & LARYNGOTRACHEOBRONCHITIS
• Infectious croup
• Viral infection with parainfluenza type 1 – MC
• Also parainfluenza types 2 & 3 , influenza virus , adenovirus
& rhinovirus
• Mild cold develops to brassy cough & mild inspiratory stridor
• Child becomes restless , tachypnoec & hypoxic
• Cyanosis appears
• As obstruction worsens breath sounds become inaudible &
stridor apparently decreases
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11. STEEPLE SIGN
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12. SPASMODIC CROUP
• Occurs between 1-3 years
• Child wakes up early in morning with brassy cough &
noisy breathing
• Recurrent episodes but complete recovery
• Cause – unknown
• Mgmt. : humidification of the child’s room
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13. MANAGEMENT
• Hospitalization
• Rapid airway management
• Intubation
• Broad spectrum antibiotics ( coamoxiclav, ceftriaxone ..)
• Rx with nebulized epinephrine
• Single i.m dose of dexamethasone
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14. OTHER INFECTIONS
BACTERIAL TRACHEITIS
RETROPHARYNGEAL ABSCESS
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15. CONGENITAL CAUSES
LARYNGOMALACIA
• MC congenital laryngeal anomaly & MC cause of infant stridor
• Inspiratory stridor – hallmark aggravated while supine or crying
• Dx : flexible endoscopy – partial collapse of flaccid supraglottic
airway with inspiration
• Its benign & resolve by 18 months
• Rx : surgical intervention in case of resp. distress
or FTT
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16. VOCAL CORD PARALYSIS
• 2nd MC congenital laryngeal anomaly
• B/L VCP – high pitched inspiratory stridor &
cyanosis
• Idiopathic or mostly iatrogenic ( Erb’s palsy of
recurrent nerve during vaginal delivery )
• U/L VCP – mild stridor &/or aspiration
• MCC-Iatrogenic injury during ligation of PDA
• Rx : tracheostomy in B/L VCP
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17. CONGENITAL SUBGLOTTIC STENOSIS
• 3rd MC congenital laryngeal anomaly
• Cause : incomplete recanalization of laryngotracheal tube
during embryonic development
• C/F : recurrent episodes of biphasic stridor (mis dx. as croup)
• Severe cases tracheostomy & surgical excision of stenosis
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18. VASCULAR RING
• Great vessel anomaly causing
compression of both trachea &
oesophagus
• C/F : stridor & dysphagia
• Rx : surgical
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19. SUBGLOTTIC HEMANGIOMA
• Benign vascular tumor present in trachea
• Biphasic stridor with barking cough
 CONGENITAL SACCULAR CYST
 LARYNGEAL WEB
 LARYNGEAL ATRESIA
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20. IATROGENIC CAUSES
ACQUIRED SUBGLOTTIC STENOSIS
• MC congenital laryngeal anomaly & MC cause of infant stridor
• Inspiratory stridor – hallmark aggravated while supine or crying
• Dx : flexible endoscopy – partial collapse of flaccid supraglottic
airway with inspiration
• Its benign & resolve by 18 months
• Rx : surgical intervention in case of resp. distress
or FTT
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22.  LARYNGEAL GRANULOMA
• Results from prolonged intubation
• Dx : Endoscopy reveals vocal cord granuloma
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23. NEOPLASMS
RECURRENT RESPIRATORY PAPPILOMA
• MC benign laryngeal TUMOR
• Presents with gradual airway obstruction
• Caused by HPV types 6 & 11
• MOT : Passage of fetus through infected birth canal
• Dx : Endoscopy – single or multiple irregular warty masses
in larynx or pharynx
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24. • Rx : CO2 laser ablation or excision of the papilloma
anti virals & interferons
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25. FOREIGN BODY ASPIRATION
• Potential cause of stridor in children
• MC are food & coins
• Urgent endoscopic visualization required
• Immediate removal by surgery
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