Shortness of breath

Acute coronary syndrome

Acute coronary syndrome frequently presents with retrosternal chest discomfort and difficulty catching the breath.^[2] It however may atypically present with shortness of breath alone.^[15] Risk factors include old age, smoking, hypertension, hyperlipidemia, and diabetes.^[15] An electrocardiogram and cardiac enzymes are important both for diagnosis and directing treatment.^[15] Treatment involves measures to decrease the oxygen requirement of the heart and efforts to increase blood flow.^[2]

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.^{[citation needed]}

Congestive heart failure

Congestive heart failure frequently presents with shortness of breath with exertion, orthopnea, and paroxysmal nocturnal dyspnea.^[2] It affects between 1 and 2% of the general United States population and occurs in 10% of those over 65 years old.^[2][15] Risk factors for acute decompensation include high dietary salt intake, medication noncompliance, cardiac ischemia, abnormal heart rhythms, kidney failure, pulmonary emboli, hypertension, and infections.^[15] Treatment efforts are directed toward decreasing lung congestion.^[2]

Chronic obstructive pulmonary disease

People with chronic obstructive pulmonary disease (COPD), most commonly emphysema or chronic bronchitis, frequently have chronic shortness of breath and a chronic productive cough.^[2] An acute exacerbation presents with increased shortness of breath and sputum production.^[2] COPD is a risk factor for pneumonia; thus this condition should be ruled out.^[2] In an acute exacerbation treatment is with a combination of anticholinergics, beta₂-adrenoceptor agonists, steroids and possibly positive pressure ventilation.^[2]

Asthma

Asthma is the most common reason for presenting to the emergency room with shortness of breath.^[2] It is the most common lung disease in both developing and developed countries affecting about 5% of the population.^[2] Other symptoms include wheezing, tightness in the chest, and a nonproductive cough.^[2] Inhaled corticosteroids are the preferred treatment for children, however, these drugs can reduce the growth rate.^[16] Acute symptoms are treated with short-acting bronchodilators.^{[citation needed]}

Pneumothorax

Pneumothorax presents typically with pleuritic chest pain of acute onset and shortness of breath not improved with oxygen.^[2] Physical findings may include absent breath sounds on one side of the chest, jugular venous distension, and tracheal deviation.^[2]

Pneumonia

The symptoms of pneumonia are fever, productive cough, shortness of breath, and pleuritic chest pain.^[2] Inspiratory crackles may be heard on exam.^[2] A chest x-ray can be useful to differentiate pneumonia from congestive heart failure.^[2] As the cause is usually a bacterial infection, antibiotics are typically used for treatment.^[2]

Pulmonary embolism

Pulmonary embolism classically presents with an acute onset of shortness of breath.^[2] Other presenting symptoms include pleuritic chest pain, cough, hemoptysis, and fever.^[2] Risk factors include deep vein thrombosis, recent surgery, cancer, and previous thromboembolism.^[2] It must always be considered in those with acute onset of shortness of breath owing to its high risk of mortality.^[2] Diagnosis, however, may be difficult^[2] 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 (low blood pressure) may warrant the use of thrombolytic drugs.^[2]

Anemia

Anemia that develops gradually usually presents with exertional dyspnea, fatigue, weakness, and tachycardia.^[17] It may lead to heart failure.^[17] 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.^{[18][citation needed]}

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.^[19] Treatments include both nonpharmacological and pharmacological interventions. Nonpharmacological interventions that showed improvement in breathlessness include fans, behavioral and pyschoeducational approaches, exercise, and pulmonary rehabilitation. Integrative medicine options include acupuncture/acupressure/reflexology, meditation, and music therapy, with acupuncture/reflexology found to have a beneficial effect.^[20]

Other

Other important or common causes of shortness of breath include cardiac tamponade, anaphylaxis, interstitial lung disease, panic attacks,^[6][12][17] and pulmonary hypertension. It is more common among people with relatively small lungs.^[21] Around 2/3 of women experience shortness of breath as a part of a normal pregnancy.^[9]

Cardiac tamponade presents with dyspnea, tachycardia, elevated jugular venous pressure, and pulsus paradoxus.^[17] The gold standard for diagnosis is ultrasound.^[17]

Anaphylaxis typically begins over a few minutes in a person with a previous history of the same.^[6] Other symptoms include urticaria, throat swelling, and gastrointestinal upset.^[6] The primary treatment is epinephrine.^[6]

Interstitial lung disease presents with a gradual onset of shortness of breath typically with a history of predisposing environmental exposure.^[12] Shortness of breath is often the only symptom in those with tachydysrhythmias.^[15]

Panic attacks typically present with hyperventilation, sweating, and numbness.^[6] They are however a diagnosis of exclusion.^[12]

Neurological conditions such as spinal cord injury, phrenic nerve injuries, Guillain–Barré syndrome, amyotrophic lateral sclerosis, multiple sclerosis and muscular dystrophy can all cause an individual to experience shortness of breath.^[11] Shortness of breath can also occur as a result of vocal cord dysfunction (VCD).^[22]

Sarcoidosis is an inflammatory disease of unknown etiology that generally presents with dry cough, fatigue, and shortness of breath, although multiple organ systems may be affected, with the involvement of sites such as the eyes, the skin, and the joints.^[23]

Blood tests

Several labs may help determine the cause of shortness of breath. D-dimer, while useful to rule out a pulmonary embolism in those who are at low risk, is not of much value if it is positive, as it may be positive in several conditions that lead to shortness of breath.^[15] A low level of brain natriuretic peptide is useful in ruling out congestive heart failure; however, a high level, while supportive of the diagnosis, could also be due to advanced age, kidney failure, acute coronary syndrome, or a large pulmonary embolism.^[15]

Imaging

A chest x-ray is useful to confirm or rule out a pneumothorax, pulmonary edema, or pneumonia.^[15] Spiral computed tomography with intravenous radiocontrast is the imaging study of choice to evaluate for pulmonary embolism.^[15]

Physiotherapy

Individuals can benefit from a variety of physical therapy interventions.^[30] Persons with neurological/neuromuscular abnormalities may have breathing difficulties due to weak or paralyzed intercostal, abdominal and/or other muscles needed for ventilation.^[31] Some physical therapy interventions for this population include active assisted cough techniques,^[32] volume augmentation such as breath stacking,^[33] education about body position and ventilation patterns^[34] and movement strategies to facilitate breathing.^[33] Pulmonary rehabilitation may alleviate symptoms in some people, such as those with COPD, but will not cure the underlying disease.^[35][36] Fan therapy to the face has been shown to relieve shortness of breath in patients with a variety of advanced illnesses including cancer.^[37] The mechanism of action is thought to be stimulation of the trigeminal nerve.

Palliative medicine

Systemic immediate release opioids are beneficial in emergently reducing the symptom severity of shortness of breath due to both cancer and non-cancer causes;^[3][38] long-acting/sustained-release opioids are also used to prevent/continue treatment of dyspnea in palliative setting. There is a lack of evidence to recommend midazolam, nebulised opioids, the use of gas mixtures, or cognitive-behavioral therapy yet.^[39]

Non-pharmacological techniques

Non-pharmacological interventions provide key tools for the management of breathlessness.^[19] Potentially beneficial approaches include active management of psychosocial issues (anxiety, depression, etc.), and implementation of self-management strategies, such as physical and mental relaxation techniques, pacing techniques, energy conservation techniques, learning exercises to control breathing, and education.^[19] The use of a fan may be beneficial.^[19] Cognitive behavioural therapy may also be helpful.^[19]

Pharmacological treatment

For people with severe, chronic, or uncontrollable breathlessness, non-pharmacological approaches to treating breathlessness may be combined with medication. For people who have cancer that is causing the breathlessness, medications that have been suggested include opioids, benzodiazepines, oxygen, and steroids.^[19] Results of recent systematic reviews and meta-analyses found opioids were not necessarily associated with more effectiveness in treatment for patients with advanced cancer.^[40][41]

Ensuring that the balance between side effects and adverse effects from medications and potential improvements from medications needs to be carefully considered before prescribing medication.^[19] The use of systematic corticosteroids in palliative care for people with cancer is common, however, the effectiveness and potential adverse effects of this approach in adults with cancer have not been well studied.^[19]