Some Causes of Stridor
Cause | Suggestive Findings | Diagnostic Approach |
|---|---|---|
Acute stridor | ||
Allergic reaction (severe) | Abrupt onset after exposure to an allergen Usually accompanied by wheezing and sometimes orofacial edema; itching No fever or sore throat; cough rare | History and physical examination |
Often swelling of the face, lips, and/or tongue Often in people at risk (eg, exposure to an allergen, use of an ACE inhibitor, personal or family history of hereditary angioedema) | History and physical examination Sometimes indirect laryngoscopy | |
Bacterial tracheitis (rare) | Barking cough that is worse at night, high fever, and respiratory distress Toxic appearance (eg, lethargy, poor perfusion) | Neck radiography Sometimes direct or indirect laryngoscopy with visualization and culture of purulent tracheal secretions |
Age 6–36 months Barking cough that is worse at night, URI symptoms, no difficulty swallowing, low-grade fever | History and physical examination Sometimes anteroposterior neck radiograph showing subglottic narrowing (steeple sign) | |
More common in adults Abrupt onset of high fever, sore throat, drooling, and often respiratory distress and marked anxiety Toxic appearance (eg, lethargy, poor perfusion) | Lateral neck radiograph if the patient is stable Examination in operating room if any signs of distress | |
Sudden onset in a toddler or young child who has no URI or constitutional symptoms In adults, foreign body in upper airway typically apparent by history | Direct or indirect laryngoscopy or bronchoscopy | |
Inhalation injury (eg, due to cleaning agents, smoke inhalation) | Clinically evident recent toxic inhalation | History and physical examination Sometimes bronchoscopy |
Laryngospasm | May occur due to gastroesophageal reflux or anesthesia, or after endotracheal intubation | Direct or indirect laryngoscopy |
Postextubation complications (eg, laryngeal edema, laryngospasm, arytenoid dislocation) | Recent intubation and respiratory distress | History and physical examination Sometimes direct laryngoscopy |
Mainly in children < 4 years High fever, severe throat pain, drooling, trouble swallowing, sometimes respiratory distress Swelling that may or may not be visible in the pharynx | Lateral neck radiograph Sometimes neck CT with contrast | |
Recurrent episodes of unexplained stridor often with hoarseness, throat tightness, a choking sensation, wheezing, and/or cough | Direct laryngoscopy | |
Chronic stridor | ||
Bilateral vocal fold paralysis or dysfunction | Recent trauma (eg, during birth, thyroid or other neck surgery, intubation, or deep airway suctioning) Various neurodegenerative or neuromuscular disorders present Good voice quality but limited intensity (ie, loudness) | Direct or indirect laryngoscopy |
Congenital anomalies (numerous; laryngomalacia most common) | Usually in neonates or infants Sometimes other congenital anomalies present Sometimes trouble feeding or sleeping Sometimes worse with URI | CT of neck and chest Direct laryngoscopy Spirometry with flow-volume loops |
Congenital tracheomalacia | Chronic symptoms Stridor or barky cough during coughing, crying, or feeding May worsen in the supine position | CT or MRI Spirometry with flow-volume loops Sometimes bronchoscopy |
External compression | History of head and neck cancer or obvious mass, night sweats, and weight loss | Radiograph of neck and chest CT of neck and chest Direct or indirect laryngoscopy |
Laryngeal tumors (eg, squamous cell carcinoma, hemangiomas, small cell carcinoma) | Inspiratory or biphasic stridor that may progressively worsen as tumor enlarges | Direct or indirect laryngoscopy Spirometry with flow-volume loops |
ACE = angiotensin-converting enzyme; CT = computed tomography; MRI = magnetic resonance imaging; URI = upper respiratory infection. | ||