What Is Stridor?
Stridor is a high-pitched, harsh breathing sound caused by turbulent airflow through a narrowed or partially obstructed airway. This distinctive sound typically originates in the upper respiratory tract, including the larynx (voice box), trachea (windpipe), and pharynx (throat). It signals an underlying issue impeding normal air passage.
The characteristic sound of stridor can vary, sometimes described as whistling or crowing, and its specific quality often provides clues about the location of the airway compromise. Stridor can be classified based on when it occurs during the breathing cycle. Inspiratory stridor, heard during inhalation, generally suggests an obstruction above the vocal cords in the larynx or pharynx. Expiratory stridor, occurring during exhalation, often indicates a blockage in the lower trachea or bronchi. When stridor is heard during both inhalation and exhalation, it is termed biphasic, and this usually points to a fixed obstruction at the level of the vocal cords or subglottic region within the trachea.
Recognizing Urgent Stridor
Recognizing urgent stridor is important, as it often indicates a medical emergency. Increasing difficulty in breathing, manifesting as rapid breathing, nasal flaring, or visible retractions (skin pulling in around ribs or neck), is a concerning indicator. Cyanosis, a bluish discoloration of the lips, face, or fingernails, signals a severe lack of oxygen and requires emergency medical intervention.
Other alarming signs include drooling or an inability to swallow, suggesting a throat obstruction. Any altered mental state, such as unusual lethargy, agitation, or decreased responsiveness, indicates insufficient oxygen to the brain. Stridor that develops rapidly or suddenly worsens is also a cause for immediate concern. If any of these urgent signs are present, contact emergency medical services without delay.
Professional Diagnosis and Management
Effective stridor management begins with a professional diagnosis to identify the underlying cause, as treatment targets the specific condition. Healthcare professionals gather a detailed patient history, inquiring about the onset, duration, and associated symptoms. A comprehensive physical examination follows, focusing on the respiratory system and observing breathing patterns and general condition.
Diagnostic tests are often necessary to pinpoint the exact location and nature of the airway obstruction. Imaging studies, such as plain film radiographs of the neck and chest, can help visualize the airway, while computed tomography (CT) scans may provide more detailed cross-sectional views. More invasive procedures, like flexible fiberoptic laryngoscopy or bronchoscopy, allow direct visualization of the larynx and trachea to identify anomalies such as foreign bodies, inflammation, or structural abnormalities. Blood tests, including arterial blood gas analysis, may be performed to assess oxygen and carbon dioxide levels in the blood, indicating the severity of respiratory compromise.
Once the underlying cause is identified, medical management varies widely. For inflammation, corticosteroids reduce airway swelling. Infections are treated with antibiotics for bacterial pathogens or antiviral medications for viral causes. Nebulized epinephrine can reduce airway edema in severe swelling or croup.
Foreign bodies obstructing the airway require medical removal. Structural abnormalities or tumors may necessitate surgical correction. In severe cases of airway compromise, interventions like intubation or tracheostomy may be required to secure breathing.
Supportive Measures and Prevention
While professional medical care is essential for managing stridor, supportive measures can help individuals, especially while awaiting or following treatment. Maintaining a calm environment and reassuring the individual can reduce anxiety, which might exacerbate breathing difficulties. For some conditions, a humid environment from a cool-mist humidifier may offer relief by moistening the airway, but this should always be done under medical guidance.
Advisably, avoid known airway irritants like cigarette smoke, strong fumes, or allergens, as these can worsen respiratory symptoms. These supportive actions complement, but do not replace, professional medical intervention. For prevention, general strategies include effectively managing chronic respiratory conditions like asthma to prevent exacerbations that could narrow the airway. Avoiding exposure to known allergens and irritants can reduce the risk of respiratory distress.