MedlinePlus Medical Encyclopedia: Breathing sounds

Skip navigation


Medical Encyclopedia
Other encyclopedia topics:	A-Ag Ah-Ap Aq-Az B-Bk Bl-Bz C-Cg Ch-Co Cp-Cz D-Di Dj-Dz E-Ep Eq-Ez F G H-Hf Hg-Hz I-In Io-Iz J K L-Ln Lo-Lz M-Mf Mg-Mz N O P-Pl Pm-Pz Q R S-Sh Si-Sp Sq-Sz T-Tn To-Tz U V W X Y Z 0-9

Breathing sounds - abnormal (stridor)

Contents of this page:
Alternative names Definition Considerations Common Causes	Home Care Call your health care provider if What to expect at your health care provider's office

Alternative names

Stridor

Definition Return to top

Stridor is an abnormal, high-pitched, musical breathing sound caused by a blockage in the throat or larynx, also called an extrathoracic airway obstruction. It is usually heard when inhaling (see wheezing and abnormal lung sounds). Stridor may indicate an emergency and should always be evaluated immediately by a health care provider.

Considerations Return to top

Children are at higher risk of airway obstruction because they have narrower airways than adults. In young children, stridor is a significant sign of airway obstruction and must be treated immediately in order to prevent total airway obstruction.

The airway can be obstructed by an object, by swelling of the tissues of the throat or upper airway, or by spasm of the airway muscles or the vocal cords.

Common Causes Return to top

Inhalation of an object such as a peanut or marble (foreign body aspiration)
Laryngitis (acute)
Airway trauma
Allergic reaction
Croup
Enlarged tonsils or adenoids (such as with tonsillitis)
Abscess on the tonsils
Inhalation injury (such as smoke inhalation)
Neck surgery
Neck or facial swelling
Secretions, particularly phlegm (sputum)
Vocal cord cancer
Prolonged intubation (breathing assisted with a tube)
Diagnostic tests such as bronchoscopy or laryngoscopy

Home Care Return to top

Follow prescribed therapy in treating the underlying cause. See also first-aid measures for choking.

Call your health care provider if Return to top

Call your health care provider if there is any indication of unexplained stridor, especially in a child.

What to expect at your health care provider's office Return to top

In emergency situations, vital signs (temperature, pulse, rate of breathing, blood pressure) will be monitored, and the Heimlich maneuver may be necessary. Then the medical history will be obtained, and a physical examination performed. Intubation (insertion of a "breathing tube") may be necessary if there is inability to breathe properly (respiratory failure).

Medical history questions documenting abnormal breathing sounds in detail may include:

Is the abnormal breathing sound a high-pitched sound?
Did it begin suddenly?
Is it possible that the child may have put something in the mouth and gotten it into the windpipe?
Has the child been ill recently?
Is the child's neck or face swollen?
Has the child been coughing or complaining of a sore throat?
What other symptoms are also present?
Is there nasal flaring?
Is the child using chest muscles to breathe (intercostal retractions)?
Does the child have blue lips, blue nailbeds, or bluish color of the skin?

The physical examination will include monitoring the vital signs and listening to the lungs.

Diagnostic tests that may be performed include:

Arterial blood gas analysis
Bronchoscopy (using a scope to look directly at the airway)
CT scan, thoracic
Laryngoscopy
X-ray of the chest

After seeing your health care provider:
You may want to add a diagnosis related to stridor to your personal medical record.

Update Date: 11/10/2003

Updated by: John Goldenring, M.D., MPH, Department of Pediatrics, Children's Hospital, San Diego, CA. Review provided by VeriMed Healthcare Network.

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 2002 A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.