Shortness of Breath / Dyspnea
Dyspnea is the sensation of difficult, uncomfortable, or inadequate breathing. It can have many causes and should be evaluated in context.[1]
Possible contributors
- Lung conditions such as asthma, COPD, pneumonia, or pulmonary fibrosis
- Heart conditions, anemia, deconditioning, medications, or anxiety
- Sleep-related breathing disorders
- Upper airway, allergy, sinus, or reflux-related contributors
Evaluation basics
Evaluation may include history, exam, oxygen assessment, lung function testing, imaging, laboratory tests, or sleep testing depending on the situation.[1]
Warning signs
New, severe, rapidly worsening shortness of breath, chest pain, fainting, blue lips, confusion, or low oxygen should be evaluated urgently.
How is dyspnea evaluated?
Evaluation depends on onset, severity, and clinical context. History and physical exam remain the starting point.[1]
Common diagnostic tests
- Pulse oximetry: A non-invasive finger clip to measure oxygen saturation. Quick and painless.
- Spirometry / pulmonary function tests: Breathing tests for obstructive or restrictive lung patterns.[2]
- Chest X-ray: Initial imaging for pneumonia, pleural effusion, pneumothorax, or structural abnormalities.
- CT scan of the chest: More detailed imaging (e.g., CT angiography for pulmonary embolism, HRCT for interstitial lung disease).
- Echocardiogram: Heart ultrasound to evaluate cardiac function, valve problems, and pulmonary pressures.
- Blood tests: CBC (anemia), BNP (heart failure), D-dimer (blood clot), thyroid function.
Specialized tests
- Arterial blood gas (ABG): Precisely measures oxygen, CO2, and acid-base status from an arterial blood sample.
- Cardiopulmonary exercise testing (CPET): Measures breathing, heart function, and gas exchange during exercise. Useful for unexplained dyspnea.[1] Learn more about CPET →
- Diffusing capacity (DLCO): Measures gas transfer efficiency. Reduced in emphysema, fibrosis, or pulmonary vascular disease.
- Sleep study: If sleep-disordered breathing is suspected.
- Laryngoscopy: Visualization of vocal cords if vocal cord dysfunction is suspected.
Treatment approach
Treatment depends on the underlying cause.[1]
- Asthma or COPD → inhalers and disease-specific treatments
- Heart failure → medications, fluid management, lifestyle modifications
- Anemia → iron supplementation, evaluation of blood loss
- Pulmonary embolism → anticoagulation
- Deconditioning → graded exercise, pulmonary rehabilitation
- Pulmonary fibrosis → antifibrotic therapy, oxygen, rehabilitation
- Anxiety-related breathing patterns → breathing retraining, counseling
For persistent dyspnea despite treatment, pulmonary rehabilitation, breathing techniques, supplemental oxygen, and management of comorbidities may help.[1]
Related topics
References
- Parshall MB, Schwartzstein RM, Adams L, et al. An official American Thoracic Society statement: update on the mechanisms, assessment, and management of dyspnea. Am J Respir Crit Care Med. 2012;185(4):435-452. doi:10.1164/rccm.201111-2042ST
- Graham BL, Steenbruggen I, Miller MR, et al. Standardization of spirometry 2019 update. Am J Respir Crit Care Med. 2019;200(8):e70-e88. doi:10.1164/rccm.201908-1590ST