Breathing, like the rest of our vital body system, operates continuously throughout the day. Given the fact that we inhale around 6 liters of air every minute, it’s impressive how the process goes unnoticed. Only when we have breathing difficulties, we realize how important this physiological process is.
Understanding shortness of breath
Commonly described by the patient either as ‘not getting enough air’, ‘increased effort to breathe’, ‘chest tightness’, and ‘air hunger’, shortness of breath, or medically known as dyspnea is a subjective and nonspecific symptom, yet very distressing for those who experience it. It is best described and quantified by the patients at the time they experience the symptom.
Shortness of breath may come in acute or chronic form. Acute conditions are severe and sudden in onsets such as foreign body obstruction in the airway or an asthma attack. A chronic condition, by contrast, develops gradually and worsens over an extended period of time such as congestive heart failure or asthma.
Causes of shortness of breath
Shortness of breath can be classified as acute and chronic, or based on its origin; either pulmonary, cardiac, upper airway, central nervous, psychogenic, musculoskeletal, or endocrine origin. Shortness of breath is commonly caused by lung or cardiovascular ailments. But other causes may also be involved such as panic attack (psychogenic), neuromuscular disease (musculoskeletal) and metabolic acidosis (endocrine). Certain drugs may also trigger shortness of breath.
Nevertheless, common causes of shortness of breath generally include:
Chronic obstructive pulmonary disease (COPD), is a progressive lung disease characterized by persistent respiratory symptoms and airflow limitation. The airflow limitation is caused by a combination of small airways diseases like emphysema (damaged air sacs), chronic bronchitis and refractory (non-reversible) asthma. The patients are usually over 40 years old and are nearly always current or former smokers. COPD can cause both acute and chronic shortness of breath in an adult.
Asthma is a respiratory disease characterized by chronic airway inflammation leading to variable airway obstruction. The inflamed airways swell, tighten, and produce excess mucus, causing difficulties in breathing.
Multiple allergies may be present in patients with asthma. The precipitating factors can include respiratory irritation, allergen exposure, exercise, weather changes, and respiratory tract infections. Asthma itself is a chronic condition but episodes of acute attack due to precipitating factors called exacerbations may happen. In this situation, the asthma symptoms suddenly worsen, causing the airways to swell and mucus is thicker than usual.
Pneumonia is an inflammation of one or both lung caused by bacteria, viruses or fungal infection. The inflamed air sac in the lung will fill with fluid or pus, causing difficulty breathing. You may complain of pain, fever, and cough from pneumonia. Shortness of breath is the main complaint from elderly patients with pneumonia. It can cause both acute and chronic shortness of breath.
Interstitial lung diseases
An interstitial lung disease is a group of lung diseases affecting the interstitium (the tissue and space around the air sacs of the lungs). It may occur when an injury to the lungs triggers an abnormal healing response causing the interstitium to be scarred and thickened. This makes it more difficult for oxygen to pass into the bloodstream.
Most patients with interstitial lung disease complained of chronic shortness of a breath and dry cough, and they are often smokers.
Pulmonary embolism is an obstruction of the pulmonary artery in the lungs by a substance that has moved from elsewhere in the body through the bloodstream (embolism). The manifestation of acute pulmonary embolism is often characterized by acute onset shortness of breath. Patients often report chest pain and sometimes have a bloody cough.
Pulmonary embolism usually occurs as a result of the blood clot from lower limb migrating to the lung circulation. This blood clot may occur during pregnancy, obesity, cancer and other predisposed condition in which the patient has a higher risk of formation of blood clot in the body.
Congestive heart failure
Congestive heart failure, also simply known as heart failure is a chronic progressive condition of the declined pumping function of the heart. It may occur gradually due to the underlying condition that causes the heart to weaken or stiff to fill and pump efficiently.
The causes include narrowing of the arteries around the heart (coronary artery disease) hypertension and valvular heart disease. Decrease blood pumped to the body organ causes shortness of breath, fatigue, diminished exercise tolerance, and fluid retention.
The majority of cases of shortness of breath are due to chronic cardiopulmonary (heart and lung) conditions. As a matter of fact, heart and lung diseases are often present in the same patient at the same time. Your healthcare provider may search for both causes if you complain from shortness of breath. If you suffer from shortness of breath, do not panic and seek help from your healthcare provider. Although it may be a sign of an underlying cardiopulmonary condition, you should also consider anemia, obesity and lack of fitness as a cause.
Keep in mind that these causes are mostly affecting adults. As for children, acute attack of shortness of breath commonly occurs due to viral infections and inflammation on the part of the respiratory airway that they are susceptible to. This includes inflammation of the bronchioles (bronchiolitis), larynx (croup), and epiglottis (epiglottitis). Given their curious nature, your child may also suffer from shortness of breath due to foreign body aspiration. The object may lodge in their airway and they may require emergency intervention.
Hello Health Group does not provide medical advice, diagnosis or treatment.
Review Date: July 20, 2018 | Last Modified: July 20, 2018
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Croucher, Beth. "The Challenge of Diagnosing Dyspnea:" AACN Advanced Critical Care 25, no. 3 (2014): 284–90. https://doi.org/10.1097/NCI.0000000000000044.