Asthma is a chronic disease of the airways of your lungs. These airways are also known as bronchial tubes. It is a chronic disorder characterized by shortness of breath, wheezing, coughing and tightness of the chest.
Asthma is one disease that has two main components occurring deep within the airways of your lungs:
Airway Constriction: The muscles around the airways in the lungs squeeze together or tighten. This tightening is often called "bronchoconstriction," and it can make it hard for a person to breathe the air in or out of their lungs.
Airway Inflammation: The airways of the lungs are always inflamed if a person has asthma, and become more swollen and irritated when an attack begins. Their healthcare professional may refer to this swelling as "inflammation."
Inflammation can reduce the amount of air that a person can take in or breathe out of their lungs. In some cases, the mucus glands in the airways produce excessive, thick mucus, further obstructing the airways.
Airway constriction and inflammation together cause narrowing of the airways, which can result in wheezing, coughing, chest tightness, or shortness of breath. In people with asthma, the airways are inflamed even when they're not having symptoms.
How do you get Asthma?
Asthma can arise at any age, but why some people have the disease and others don't is not known. People with asthma have airways that are more sensitive than normal.
- Doctors know, however, that asthma can sometimes run in families.
- Asthma attacks can be set off by many different things, these are called triggers. Examples include cold air, vigorous exercise and stress.
- These triggers may also include 'allergens'. These are present in the environment and contain chemicals that trigger allergic reactions.
- Allergens include, for example, pollen, animal dander's, house dust, pollution, some foods, perfumes and cigarette smoke.
- Allergens cause the lining of the airways to become swollen and inflamed. It produces extra mucus and the muscles of the airways tighten. There is then less room for the air to pass in and out.
- Attacks may be more frequent or severe in people who have a chest infection.
Signs & Symptoms
Signs of an asthmatic episode include :
wheezing, rapid breathing (tachypnea), prolonged expiration, a rapid heart rate (tachycardia), rhonchous lung sounds (audible through a stethoscope), and over-inflation of the chest. During a serious asthma attack, the accessory muscles of respiration (sternocleidomastoid and scalene muscles of the neck) may be used, shown as in-drawing of tissues between the ribs and above the sternum and clavicles, and the presence of a paradoxical pulse (a pulse that is weaker during inhalation and stronger during exhalation).
During very severe attacks, an asthma sufferer can turn blue from lack of oxygen, and can experience chest pain or even loss of consciousness. Just before loss of consciousness, there is a chance that the patient will feel numbness in the limbs and palms may start to sweat. Feet may become icy cold. Severe asthma attacks may lead to respiratory arrest and death. Despite the severity of symptoms during an asthmatic episode, between attacks an asthmatic may show few signs of the disease.
Treatment of asthma can be divided into long-term control and quick-relief medications.
- Long-term control medications are taken daily to maintain control of persistent asthma. They primarily serve to control airway inflammation.
- The quick-relief medications are taken to achieve prompt reversal of an acute asthma "attack" by relaxing bronchial smooth muscle.