Definition: Difficult noisy respiration indicating partial airway obstruction in larynx &/or trachea.
Types:
a. Inspiratory laryngeal: at or above glottis.
b. Biphasic: subglottic or tracheal.
c. Expiratory: bronchial.
Causes of stridor:
I. Congenital:
- Congenital web
- Laryngo malacia.
- Subglottic stenosis
- Subglottic haemangioma.
- Congenital cyst
- Congenital bilateral cord palsy
II. Traumatic:
- Mechanical: Sharp, blunt, surgical, intubation, F.B.
- Physical: Radiotherapy, thermal.
- Chemical: Corrosives.
III. Inflammatory:
- Acute non-specific laryngitis, in children
- Acute epiglottitis.
- Acute laryngotracheobronchitis in children.
- Laryngeal diphtheria.
- Chronic specific laryngitis (granulomas)
IV. Neoplastic
- Benign: Multiple papillomatosis, subglottic chondroma.
- Malignant: Carcinoma.
V. Miscellaneous
- Neurological: Bilateral abductor paralysis. Laryngeal spasm e.g. tetany
- Tumor like conditions: Laryngeal cysts, laryngocele, amyloidosis.
- Laryngeal oedema.
VI. Tracheal causes
- Retrosternal goiter, mediastinal LN, thymus hyperplasia,& deep neck infection
Clinical picture of stridor:
- Dyspnea & tachypnea.
- Irritability, restlessness, fatigue, sweating.
- Working alae nasi.
- Suprasternal, supraclavicular & intercostal retraction.
- Working accessory muscles of respiration.
- Tachycardia.
- Congested neck veins.
- Late: Cyanosis, and bradycardia. Finally: coma & cardiac arrest.