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How can shortness of breath begin suddenly?
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respiratory disease
The bronchioles of the lungs are the site where oxygen is exchanged for carbon dioxide during the process of respiration. Inflammation, infection, or obstruction of the bronchioles is often associated with acute or chronic respiratory disease, including bronchiectasis, pneumonia, and lung abscesses.
Shortness of breath, or dyspnea, can begin suddenly due to several acute medical conditions that disrupt normal respiratory function. Because sudden-onset dyspnea can be life-threatening, it is critical to seek immediate medical attention if it occurs.1
Common causes of sudden shortness of breath include:
- Acute Pulmonary Edema: This condition involves a rapid buildup of fluid in the lung's alveoli, which can occur within minutes or hours due to heart failure, severe hypertension, or other non-cardiogenic factors.1
- Acute Respiratory Distress Syndrome (ARDS): A form of respiratory failure that develops suddenly following lung injury, such as sepsis, pneumonia, or chest trauma, leading to rapid breathing and dangerously low blood oxygen levels.2
- Airway Obstruction: The inhalation of a foreign body into the trachea can cause an immediate sensation of breathlessness.3
- Asthma: A severe attack of asthma can trigger a sudden onset of dyspnea.3
- Pulmonary Embolism: The blockage of a pulmonary artery by a blood clot can cause acute congestion and sudden, severe respiratory distress.43
If you are experiencing sudden difficulty breathing, please prioritize your safety and seek emergency medical care immediately.