Shortness of breath
Shortness of breath, known as dyspnea or dyspnoea, is an uncomfortable feeling of not being able to breathe well enough. The American Thoracic Society defines it as "a subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity", and recommends evaluating dyspnea by assessing the intensity of its distinct sensations, the degree of distress and discomfort involved, and its burden or impact on the patient's activities of daily living. Distinct sensations include effort/work to breathe, chest tightness or pain, and "air hunger". The tripod position is often assumed to be a sign.
Dyspnea is a normal symptom of heavy physical exertion but becomes pathological if it occurs in unexpected situations, when resting or during light exertion. In 85% of cases it is due to asthma, pneumonia, reflux/LPR, cardiac ischemia, COVID-19, interstitial lung disease, congestive heart failure, chronic obstructive pulmonary disease, or psychogenic causes, such as panic disorder and anxiety. The best treatment to relieve or even remove shortness of breath typically depends on the underlying cause.
Definition
Dyspnea, in medical terms, is "shortness of breath".The American Thoracic Society defines dyspnea as:
"A subjective experience of breathing discomfort that consists of qualitatively distinct sensations that vary in intensity."Other definitions describe it as "difficulty in breathing", "disordered or inadequate breathing", "uncomfortable awareness of breathing", and as the experience of "breathlessness".
Causes
While shortness of breath is generally caused by disorders of the cardiac or respiratory system, others such as the neurological, musculoskeletal, endocrine, gastrointestinal system,hematologic, and psychiatric systems may be the cause.DiagnosisPro, an online medical expert system, listed 497 distinct causes in October 2010. The most common cardiovascular causes are myocardial infarction and heart failure, while common pulmonary causes include chronic obstructive pulmonary disease, asthma, pneumothorax, pulmonary edema, and pneumonia.
On a pathophysiological basis, the causes can be divided into increased awareness of normal breathing such as during an anxiety attack, an increase in the work of breathing, and an abnormality in the ventilatory or respiratory system. Ischemic strokes, hemorrhages, tumors, infections, seizures, and traumas at the brain stem can also cause shortness of breath, making them the only neurological causes of shortness of breath.
The tempo of onset and the duration of dyspnea are useful in knowing the etiology of dyspnea. Acute shortness of breath is usually connected with sudden physiological changes, such as laryngeal edema, bronchospasm, myocardial infarction, pulmonary embolism, or pneumothorax. Patients with COPD and idiopathic pulmonary fibrosis have a mild onset and gradual progression of dyspnea on exertion, punctuated by acute exacerbations of shortness of breath. In contrast, most asthmatics do not have daily symptoms, but have intermittent episodes of dyspnea, cough, and chest tightness that are usually associated with specific triggers, such as an upper respiratory tract infection or exposure to allergens.
Acute coronary syndrome
frequently presents with retrosternal chest discomfort and difficulty catching the breath. It however may atypically present with shortness of breath alone. Risk factors include old age, smoking, hypertension, hyperlipidemia, and diabetes. An electrocardiogram and cardiac enzymes are important both for diagnosis and directing treatment. Treatment involves measures to decrease the oxygen requirement of the heart and efforts to increase blood flow.COVID-19
People that have been infected by COVID-19 may have symptoms such as a fever, dry cough, loss of smell and taste, and in moderate to severe cases, shortness of breath. Dyspnea is one of the three major symptoms of Long COVID, but this subjective symptom does not track with the severity of objective markers of inflammation.Congestive heart failure
frequently presents with shortness of breath with exertion, orthopnea, and paroxysmal nocturnal dyspnea. It affects between 1 and 2% of the general United States population and occurs in 10% of those over 65 years old. Risk factors for acute decompensation include high dietary salt intake, medication noncompliance, cardiac ischemia, abnormal heart rhythms, kidney failure, pulmonary emboli, hypertension, and infections. Treatment efforts are directed toward decreasing lung congestion.Chronic obstructive pulmonary disease
People with chronic obstructive pulmonary disease, most commonly emphysema or chronic bronchitis, frequently have chronic shortness of breath and a chronic productive cough. An acute exacerbation presents with increased shortness of breath and sputum production. COPD is a risk factor for pneumonia; thus this condition should be ruled out. In an acute exacerbation treatment is with a combination of anticholinergics, beta2-adrenoceptor agonists, steroids and possibly positive pressure ventilation.Asthma
is the most common reason for presenting to the emergency room with shortness of breath. It is the most common lung disease in both developing and developed countries affecting about 5% of the population. Other symptoms include wheezing, tightness in the chest, and a nonproductive cough.Inhaled corticosteroids are the preferred treatment for children; however, these drugs can reduce the growth rate. Acute symptoms are treated with short-acting bronchodilators.
Pneumothorax
presents typically with pleuritic chest pain of acute onset and shortness of breath not improved with oxygen. Physical findings may include absent breath sounds on one side of the chest, jugular venous distension, and tracheal deviation.Pneumonia
The symptoms of pneumonia are fever, productive cough, shortness of breath, and pleuritic chest pain. Inspiratory crackles may be heard on exam. A chest x-ray can be useful to differentiate pneumonia from congestive heart failure. As the cause is usually a bacterial infection, antibiotics are typically used for treatment.Pulmonary embolism
classically presents with an acute onset of shortness of breath. Other presenting symptoms include pleuritic chest pain, cough, hemoptysis, and fever. Risk factors include deep vein thrombosis, recent surgery, cancer, and previous thromboembolism. It must always be considered in those with acute onset of shortness of breath owing to its high risk of mortality. Diagnosis, however, may be difficult and Wells Score is often used to assess the clinical probability. Treatment, depending on the severity of symptoms, typically starts with anticoagulants; the presence of ominous signs may warrant the use of thrombolytic drugs.Anemia
that develops gradually usually presents with exertional dyspnea, fatigue, weakness, and tachycardia. It may lead to heart failure. Anaemia is often a cause of dyspnea. Menstruation, particularly if excessive, can contribute to anaemia and consequential dyspnea in women. Headaches are a symptom of dyspnea in patients with anaemia. Some patients report a numb sensation in their head, and others have reported blurred vision caused by hypotension behind the eye due to a lack of oxygen and pressure; these patients have reported severe head pains, which can lead to permanent brain damage. Symptoms can include loss of concentration, focus, fatigue, language faculty impairment, and memory loss.Cancer
Shortness of breath is common in people with cancer and may be caused by numerous different factors. In people with advanced cancer, periods with severe shortness of breath may occur, along with a more continuous feeling of breathlessness.Treatments for breathlessness include both non-pharmacological and pharmacological approaches. Non-pharmacological interventions that have been shown to improve breathlessness include the use of fans, exercise, and pulmonary rehabilitation. Moderate evidence suggests the use of airflow interventions such as handheld fans has been shown to effectively reduce the feeling of breathlessness in patients with advanced cancer.
Pharmacological treatments involve bronchodilators and corticosteroids to address the underlying causes of shortness of breath, as well as opioids or anti-anxiety medications to alleviate symptoms. However, a review of breathlessness and exercise capacity in patients with advanced cancer proved the use of both opioids and anxiolytics were not effective in improving symptoms when compared to placebo. Integrative medicine options, including acupuncture, acupressure, reflexology, and meditation, have been found to have a beneficial effect.
Additional interventions can help alleviate breathessness when aligned with a patient's preferance and overall diagnosis. These may include medical procedures like stenting, thoracentesis, or pacement of pleura catheters to address bronchial obstructions or pleural effusions; cancer-directed treatments such as radiation therapy; and management of related symptoms often present in advanced cancer, including pain, can also influence the severity of breathlessness.
While these treatments are effective in reducing breathlessness in cancer patients, a systematic view reported various treatment-related side effects including equipment-related distress, fatigue, and constipation.
Psychological
One common symptom of panic disorder is shortness of breath. Panic attacks typically present with hyperventilation, sweating, and numbness. Panic disorder is usually regarded as a diagnosis of exclusion in cases of shortness of breath.When the cause of breathlessness is psychological, a common symptom is excessive sighing. This is sometimes referred to as "sigh syndrome" or "sighing dyspnea". Sigh syndrome is characterized by recurrent attempts to take a deep breath, prompted by a feeling of inability to do so, followed by a prolonged and often audible exhalation. Sigh syndrome is not dangerous and is usually self-limited, though it can be recurrent.