Dyspnea: A Review of the Current Understanding of Pathogenesis, Diagnosis, and Treatment
Abstract
Dyspnea is a common medical problem that is experienced by many individuals. It is a subjective experience of difficulty breathing and is often associated with underlying medical conditions and diseases. The pathogenesis of dyspnea is complex and still not fully understood. Diagnosis of dyspnea is mainly based on clinical history, physical examination, imaging studies, laboratory tests, and pulmonary function tests. Treatment of dyspnea is largely based on the underlying cause. This review aims to provide an overview of the current understanding of the pathogenesis, diagnosis, and treatment of dyspnea.
Keywords: Dyspnea, pathogenesis, diagnosis, treatment
Introduction
Dyspnea is a common complaint in clinical practice. It is defined as a subjective experience of difficulty in breathing, usually associated with conditions such as asthma, chronic obstructive pulmonary disease (COPD), congestive heart failure (CHF), and pulmonary embolism (PE) (1). Dyspnea is a complex phenomenon and the exact pathogenic mechanisms are not fully understood. It is also a major source of disability and significantly affects the quality of life of individuals (2). The diagnosis of dyspnea is mainly based on clinical history, physical examination, imaging studies, laboratory tests, and pulmonary function tests (3). The treatment of dyspnea is mainly based on the underlying cause. This review aims to provide an overview of the current understanding of the pathogenesis, diagnosis, and treatment of dyspnea.
Pathogenesis
The pathogenesis of dyspnea is complex and still not fully understood. It is thought to involve an interaction between afferent and efferent pathways, which eventually lead to an increase in the activity of the respiratory muscles resulting in an increased perception of effort and difficulty in breathing (4). Pulmonary diseases such as COPD, asthma, and PE can cause airway obstruction, leading to increased work of breathing and dyspnea (5). Dyspnea can also be caused by cardiac diseases such as CHF, which leads to increased pulmonary congestion resulting in increased work of breathing (6). In addition, other conditions such as anemia, anxiety, and obesity can lead to dyspnea due to decreased oxygen delivery to the tissues or increased work of breathing (7).
Diagnosis
The diagnosis of dyspnea is mainly based on the patient’s clinical history, physical examination, imaging studies, laboratory tests, and pulmonary function tests (3). The patient’s history should include the time of onset of symptoms, the duration, and the intensity of dyspnea. The physical examination should include assessment of the respiratory rate, breath sounds, chest wall movement, and use of accessory muscles of respiration. Imaging studies such as chest radiography, computed tomography (CT) scan, and positron emission tomography (PET) scan may be used to identify the underlying cause of dyspnea (8). Laboratory tests such as complete blood count (CBC), electrolytes, and arterial blood gas analysis may be performed to assess the patient’s oxygenation status (9). Pulmonary function tests such as spirometry and diffusing capacity of the lung for carbon monoxide (DLCO) may also be used to assess the patient’s respiratory function (10).
Treatment
The treatment of dyspnea is mainly based on the underlying cause. In cases of asthma and COPD, bronchodilators such as β 2 -agonists and anticholinergics may be used to relieve the airway obstruction and improve the patient’s symptoms (11). In cases of CHF, diuretics may be used to reduce the pulmonary congestion and improve the patient’s symptoms (12). In cases of anemia, iron supplements or blood transfusions may be used to improve the oxygen delivery to the tissues (13). In cases of anxiety, psychotherapy and medications such as selective serotonin reuptake inhibitors (SSRIs) may be used to reduce the symptoms of anxiety (14). In cases of obesity, a healthy diet and regular exercise may be recommended to reduce the body weight and improve the patient’s symptoms (15).
Conclusion
Dyspnea is a common medical problem that is experienced by many individuals. The pathogenesis of dyspnea is complex and still not fully understood. Diagnosis of dyspnea is mainly based on clinical history, physical examination, imaging studies, laboratory tests, and pulmonary function tests. Treatment of dyspnea is largely based on the underlying cause. This review provides an overview of the current understanding of the pathogenesis, diagnosis, and treatment of dyspnea.
References
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