Asthma is a chronic disorder of airways categorized physiologically as a reversible airflow obstruction, and pathologically with bronchoconstriction, the narrowing of the airways in the lungs due to the constriction of the surrounding smooth muscle. Asthma affects children and adolescent worldwide, caused by environmental, host, genetic factors and a variety of potential triggers. The sign and symptoms of asthma include chest tightness, wheezing, coughing, and dyspnea. One of the symptomatic treatments involves relaxing lungs smooth muscle, most commonly with inhaled β2-agonists (salbutamol).
Figure 1 :The pathophysiology of asthma
In this process, the inflammatory response developed as patients exposed to allergens such as bacteria, dust or smoke that are trapped by the mucus. These allergens bind with receptors mast cell, dendritic cells and activated IgE-dependent response mechanism. This Mast cell triggers the march inflammatory cells including neutrophil and eosinophil. Activation of mast cell by allergens through IgE-dependent mechanism also releases mediators such as histamine, tryptase, leukotrienes, and prostaglandins. The Dentritic cell which are specialized macrophage like cells in the airway epithelium are triggered by allergen to promote TH2 cell differentiation with the help of mediators such as IL-12 and tumor necrosis factor a.
The presence of inflammatory mediators causes mucus hypersecretions which will then cause formation of mucous plug that will block the airway. This will trigger hyperplasia of sumucosal gland in large airways and increased number of epithelial goblet cells. The mediators involve in this process include IL-4 and IL-13.
Inflammatory mediators also cause vasodilation of the new vessels and causes microvascular plasma leak from the vessels to the airway causing oedema to the airway. This increases airway mucosal blood flow in asthma which increases vascular volume that contributes to airway narrowing. Microvascular leakage from postcapillary venules results in airway oedema and plasma exudation into airway lumen.
Mediators including histamine, prostaglandin D2 and leukotriene also cause contraction of airway smooth muscle thus causing bronchoconstriction. In asthmatic patient there would be hyperplasia and hypertrophy of airway smooth muscle stimulated by growth factors such as platelet-derived growth factors that are released from inflammatory cells.
Basement membrane is also thickened due to subepithelial fibrosis with deposition of types III and V collagen. It occurs due to eosinophilic infiltration by release of profibrotic mediators such as transforming growth factor β. This fibrosis contributes to irreversible narrowing of airways.
Inflammatory mediators may activate sensory nerves resulting in reflex cholinergic bronchoconstriction or release of inflammatory neuropeptides which further exacerbate asthma.
Asthma is a chronic inflammatory disease of the airways. It is a reversible airway obstruction, occurring 8 to 10% of the population worldwide. According to a study in 2005, asthma affects over 15 million Americans, with more than 2 million annual emergency room visits. Asthma patients have a hyper-responsiveness in their airways and generally and increase in their airway smooth muscle cell mass. This hyperplasia is due to the normal response to the injury and repair to the airway caused by exacerbations. The main choice of therapy for asthma patients is β2- adrenergic agonists. Racemic albuterol has been the drug of choice for a short acting bronchodilator for a long time, but since the development of levalbuterol, there is the question of which drug is a better choice for therapy. Efficacy and cost of treatment must both be taken into consideration in each study of these therapies to determine which is best for the treatment of asthma.
In the article "The Effect of Theophylline and ß2 agonists on Airway Reactivity" it says that more airway responsiveness occurs in asthma, chronic bronchitis, cystic fibrosis, and other diseases. Theophylline and ß2 agonists are used commonly for maintenance therapy for symptoms associated with the increased responsiveness. Both can reduce airway responsiveness to a variety of chemical irritants.. (Ahrens 15S)
Bronchospasm is an abnormal contraction of the smooth muscle of the bronchi, narrowing and obstructing the respiratory airway, resulting in coughs, wheezing or difficulty in breathing. The chief cause of this condition is asthma, although it may also be caused by respiratory infection, chronic lung disease or an allergic reaction to chemicals. The mucosa lining of the trachea may become irritated and inflamed, which secretes mucus, causing it to be caught in the bronchi and triggers coughing.
Respiratory distress syndrome type I is a decrease production of surfactant, a noncelluar chemical produced in the type II alveolar in the lungs that's primary function is to decrease the surface tensions and attraction between the type I alveolar walls. Respiration requires the alveolar walls to inflate and deflate continuously, while ventilating the alveoli are exposed to moisture causing an attraction between the alveolar walls. (Kenner, Lott, & Flandermeyer, 271) Surfactant primary function is to neutralize the attraction to prevent alveolar collapse during deflation.
Emphysema’s target is the lungs. The inflammation caused by emphysema damages the alveoli, or air sacs. Over time, the air sacs lose their elasticity, no longer able to expand and detract like your favorite Thanksgiving elastic waist band pants. After so many Thanksgiving dinners, the elastic fibers break, and fai...
In a latex allergy, your immune system identifies latex as a harmful substance. With wheezing, runny nose or anaphylaxis, your immune system triggers certain cells to produce immunoglobulin E (IgE) antibodies to fight the latex component (the allergen). The next time you come in contact with latex, the IgE antibodies sense it and signal your immune system to release histamine and other chemicals into your bloodstream. The more exposure you have, the more your immune system is likely to respond to latex (sensitization). These chemicals cause a range of allergic signs and symptoms. Histamine is partly [sic] responsible for most allergic responses. (ACAAI)
It is used as a bronchodilator in the treatment of asthma. It is also frequently administered in asthma inhalers as the primary active drug of the inhaler. The use of Clenbuterol as a medication for asthma is primarily a European medical practice while in North America, Clenbuterol’s sister compound “Albuterol”, is utilized instead. The activation of beta-2 receptors in the cell-lining of the bronchial tubes initiates the opening and expansion of the airways (bronchial dilation) in the nose, throat and lungs. Many sympathomimetic stimulants exert this effect however Clenbuterol and Albuterol are better effective in particular for this purpose. Clenbuterol is also used in the treatment of other medical conditions, such as cardiovascular shock, heart arrhythmias, hypertension, allergic reactions and swelling, migraine headaches, anaphylactic shock and histamine
Imagine a young child competing with his or her fellow classmates during recess and immediately losing the ability to breathe normally. He or she stops in the middle of the competition and falls to the ground while holding his or her chest trying to find air. When you are young, being able to keep up with your peers during recess and sporting events is very important, however, having asthma restricts this. Asthma has a significant impact on childhood development and the diagnosis of asthma for children 18 years and younger has dramatically increased over the years. Asthma is known as a “chronic inflammation of the small and large airways” with “evident bronchial hyper-responsiveness, airflow obstruction, and in some patients, sub-basement fibrosis and over-secretion of mucus” (Toole, 2013). The constant recreation of the lung walls can even occur in young children and “lead to permanent lung damages and reduced lung function” (Toole, 2013). While one of the factors is genetics, many of the following can be prevented or managed. Obesity, exposure to secondhand smoke, and hospitalization with pneumonia in the early years of life have all been suggested to increase children’s risk of developing asthma.
Understanding the pathogenesis of asthma is a solution to creating treatments that are more effective. “For more than two decades now, asthma has been recognized as a chronic inflammatory disease involving inflammation of both the central and peripheral airways” (Tulic 71). This chronic inflammation results in structural changes in the airways of the asthmatic patient, referred to as airway remodeling. Airway remodeling is the cause of the symptoms seen in asthmatics during an attack like severe dyspnea, wheezing or difficulty in expiration (Kumar and Robbins 492). There are five major aspects of the body affected by asthma, mostly due to chronic infl...
Asthma is chronic inflammatory disorder of the airways characterized by recurring episodes of wheeling and breathlessness. It often exists with allergies and can be worsened through exposure to allergens. In fact, asthma is complicated syndromes that have neither single definition nor complete explanation to the point. In light of its treatment, it is worthwhile to notice that asthma cannot be cured, instead can be only managed by avoiding exposure to allergens and/or by using medications regularly.
An asthma attack has many effects on the body. Asthma affects the body by limiting the flow of air into the lungs. It causes airway inflammation, bronchial restriction and irregular airway obstruction. Airway inflammation is how the body reacts to something that is irritating the airways. When happening your lungs begin swelling, your breathing passageway becomes restricted and mucus is secreted. Bronchial restriction happens when the muscles in your airways tighten around the breathing tubes in your lungs. (Bronchial tubes). Mucus or fluid that is accumulated by the reaction can obstruct your airway and make it very difficult to breathe properly.
Most of you may not think of asthma as a killer disease, yet more that 5,000 Americans die of asthma each year. According to the Mayo Clinic web page, asthma also accounts for more that 400,000 hospital discharges annually. As the number of people with asthma increases, the more likely you are to come in contact with a person who has the disease. As far as I can remember, I have had asthma my whole life. My mother and one of my sisters also have asthma, so I have a first hand experience with it. This morning, I will discuss some interesting facts about asthma, I will specifically focus on what it is, warning signs, symptoms, causes, and the treatments that are used.
Chronic bronchitis is a disorder that causes inflammation to the airway, mainly the bronchial tubules. It produces a chronic cough that lasts three consecutive months for more than two successive years (Vijayan,2013). Chronic Bronchitis is a member of the COPD family and is prominently seen in cigarette smokers. Other factors such as air pollutants, Asbestos, and working in coal mines contributes to inflammation. Once the irritant comes in contact with the mucosa of the bronchi it alters the composition causing hyperplasia of the glands and producing excessive sputum (Viayan,2013). Goblet cells also enlarge to contribute to the excessive secretion of sputum. This effects the cilia that carry out the mechanism of trapping foreign bodies to allow it to be expelled in the sputum, which are now damaged by the irritant making it impossible for the person to clear their airway. Since the mechanism of airway clearance is ineffective, the secretion builds up a thickened wall of the bronchioles causing constriction and increasing the work of breathing. The excessive build up of mucous could set up pneumonia. The alveoli are also damaged enabling the macrophages to eliminate bacteria putting the patient at risk for acquiring an infection.
Asthma is a disease that currently has no cure and can only be controlled and managed through different treatment methods. If asthma is treated well it can prevent the flare up of symptoms such as coughing, diminish the dependence on quick relief medication, and help to minimize asthma attacks. One of the key factors to successful treatment of asthma is the creation of an asthma action plan with the help of a doctor that outlines medications and other tasks to help control the patient’s asthma ("How Is Asthma Treated and Controlled?"). The amount of treatment changes based on the severity of the asthma when it is first diagnosed and may be the dosage may be increased or decreased depending on how under control the patient’s asthma is. One of the main ways that asthma can be controlled is by becoming aware of the things that trigger attacks. For instance staying away from allergens such as pollen, animal fur, and air pollution can help minimize and manage the symptoms associated with asthma. Also if it is not possible to avoid the allergens that cause a patient’s asthma to flare up, they may need to see an allergist. These health professionals can help diagnosis what may need to be done in other forms of treatment such as allergy shots that can help decrease the severity of the asthma ("How Is Asthma Treated and Controlled?").
Patients who usually have allergies suffer from many symptoms due to the allergic reaction(s). Normally, your immune system protects you against invading agents such as bacteria and viruses. Otherwise harmless allergens (allergy-producing substances) cause your body to react as if they were dangerous invaders. In effect, your immune system is responding to a false alarm.