Stridor is noisy respiration produced by
turbulent air flow through the narrowed air
passages. It may be heard during
inspiration, expiration or both.
TYPES OF STRIDOR
INSPIRATORY STRIDOR – It is often
produced in obstructive lesions of
supraglottis or pharynx.
EXPIRATORY STRIDOR - It is produced in
lesions of thoracic trachea, primary and
BIPHASIC STRIDOR - It is seen in lesions of
glottis, subglottis and cervical trachea.
Types Of Stridor And Probable Site of Obstruction
Stridor is a physical sign not a disease.
Stridor is usually diagnosed on the basis of history
and physical examination, with a view to revealing
the underlying problem or condition.
Attempt should always be made to discover the
cause. It is important to elicit :
Time of onset
Mode of onset
Aspiration or ingestion of a foreign body
Stridor is always associated with respiratory
distress. There may be recession in
Suprasternal Notch, Sternum, Intercostal
Spaces & Epigastrium during inspiratory
Note whether the stridor is
inspiratory, expiratory or biphasic. Which
indicates probable site of obstruction.
Snoring or snorting – Nasal Or
Gurgling sound and muffled voice -
Horse cry or voice – Laryngeal Cause
Expiratory wheeze – Bronchial Obstruction
Associated fever – Infection ex: Acute
ASSOCIATED CHARACTERISTICS OF STRIDOR
X-ray of chest and soft tissue neck both
anteroposterior and lateral views.
Fluoroscopy to see chest movements both
during inspiration and expiration.
Tomography of chest for mediastinal mass.
Angiography , if aberrant vessels are
Once the diagnosis has been made treatment of
exact cause can be made.
Use of nebulized racemic adrenaline epinephrine in
cases where airway edema may be the cause of the
Use of dexamethasone.
Use of inhaled Heliox (70% helium, 30% oxygen); the
effect is almost instantaneous. Helium, being a less
dense gas than nitrogen, reduces turbulent flow
through the airways.
Some conditions (ex: epiglottitis, bacterial tracheitis)
may require antibiotics, while steroids may be useful
in other situations.