Types of Asthma, Its Pathophysiology and Pathology - Assignment Example

? Asthma Asthma Outline I. Introduction A. Definition of asthma B. Historical background C. Prevalence of Asthma II. Types of Asthma1. Classification by triggers A. Allergic asthma B. Seasonal asthma C. Non-allergic asthma D. Exercise-induced asthma E. Nocturnal asthma 2. Clinical classification A. Intermittent asthma B. Mild persistent asthma C. Moderate persistent asthma D. Severe persistent asthma III. Pathophysiology and pathology A. Inflammation of the airways B. Obstruction of the airflow C. Bronchial hyper-responsiveness D. Effects of asthma on the respiratory system E. Gross appearance F. Microscopic appearance IV. Diagnosis of asthma A. Clinical history of Asthma B. Physical examination of an asthmatic C. Investigations to confirm the diagnosis of asthma V. Management of asthma A. Goals in management of asthma B. Treatment and prevention VI. Conclusion and summary ASTHMA I. Introduction A. Definition. In accordance to Mill (2006), Asthma is a chronic obstructive airway disease that often becomes characterized by hyper responsiveness of the trachea-bronchial tree to various stimuli resulting to spasmodic narrowing of air passages (p.1). Another definition of asthma could be an episodic disease clinically manifested by dyspnoea, wheezing and cough. Asthma hence is a respiratory lung disease that is chronic in nature. Asthma always involves two components: In the lungs, got constriction, muscles tightening air passages, inflammation, irritation and swelling of airways. Inflammation and constriction of the airways often cause many symptoms. When asthma gets left untreated for long, often results to chronic loss of lung function plus also contribute to a condition called chronic obstructive lung disease. In asthma, once a person gets exposed to a trigger, lungs get inflamed or swollen to the extent of causing difficulties in breathing (Mills 2006, p.10). B. Historical background of asthma. The term Asthma originated from the Greek word that meant to pant, or sharp breath or exhale using open mouth. In an epic Greek poem, Iliad, asthma becomes first mentioned. Asthma became recognized in antiquity with the famous Hippocrates. Hippocrates correlated asthma to metal workers, farmers, tailors, fishermen among others. In the early times, a lot of asthma cases became associated to asthma occupations. With the recognition of asthma caused by external factors like dust and pollen, more studies became carried out to find out its pathology and effect on the respiratory system. The first well documented occupational asthma case became described in workers of castor beans in 1923 (Mills 2006, p.3). C. Prevalence of asthma. Asthma affects nearly seventeen million Americans, of which five million are children. Incidence of asthma has increased in the last 15 years by over 50 percent. Nearly five hundred thousand patients become often hospitalized due to asthma. Hence asthma belongs to among the top five expensive diseases in the health care system (Mills 2006, p.6). II. Types of asthma. Asthma can be categorized based on the basis of what triggers it. 1. Classification by triggers. A. Allergic asthma. Allergic asthma becomes often called atopic or allergic asthma. It is the commonest asthma type. It often begins in childhood or early adult life. Patients with allergic asthma have family or personal history of preceding allergic diseases like urticaria, rhinitis or infantile spasm. Patients with allergic asthma often exhibit hyper-responsive reactions to extrinsic allergens. Examples of allergens that affect such people are pollens, house dust, moulds, animal danders and others. Patients with this type often have high levels of IgE levels and test positive for skin test (Mills 2006, p.8). B. Seasonal asthma. Grass pollen, tree pollen, moulds pollen or flowers release pollen that in turn trigger this asthma. For instance, some people always find their asthma worse in the spring especially when flowers are flowering compared to other seasons. Others may find their asthma worsened in the late summer when leaves and ragweed exacerbate their condition. Such asthmas become carefully diagnosed on the basis of following a history of season appearance when a lot of allergens exist in the air (Mills 2006, p.8). C. Non-allergic asthma. This form of asthma could also be referred to as intrinsic asthma or idiosyncratic asthma or non-atopic asthma. It often starts later in adult life and got no association to a family history of asthma. Such people often have normal levels of IgE and negative skin test. In addition, such patients often develop asthma attack post an upper airway disease by viruses. Furthermore, this asthma type often gets associated with chronic bronchitis and nasal polypi. Most of these people often get asthma attacks not related to allergens. In as much as these people experience symptoms similar to those people with extrinsic form of asthma, they get not triggered by allergens. It sometimes can be triggered by tobacco smoke, room deodorizers, wood smoke, pine odors, household cleaning products, fresh paint, cooking odors, perfumes, and workplace chemicals. Respiratory infections like the common cold, sinus infection, influenza may give one symptoms related to asthma. Finally, things like exercise, sudden changes in temperature of air, cold air, and gastroesophageal reflux can trigger symptoms like non-allergic asthma (Mills 2006, p.9). D. Exercise-induced asthma. This asthma is triggered by physical activity or exercise. These symptoms often come after short exercise. Exercising for example, in the winter affects such individuals badly (Mills 2006, p.9). E. Nocturnal asthma. This can occur in asthma type. Nocturnal asthma worsens in the night, especially between 2 and 5 AM. This condition can be worsened by diseases like postnasal drip or sinus infections. Other things that may worsen this condition could be pet dander or dust mites. Adrenaline and steroids level also play a role in protecting against asthma. When the levels of these chemicals become low between 4 and 8 A.M, such individuals are more prone to getting asthma attacks at such times (Mills 2006, p.10). Clinical Classification of asthma. Symptoms Symptoms/ Night Peak Expiratory Flow or FEV1 Peak Expiratory Flow variability Intermittent Occurs less than one time in a week. Patient may be asymptomatic & have normal Peak Expiratory Flow between attacks. Occurs less or equal to two times a month   Equals or more to 80%   Less than 20% Mild persistent Occurs more than 1 time in a week but less than1 time a day. The attacks may affect activity.  Occurs than 2 times in a month More or equals to 80% Between 20-30% Moderate persistent Person Daily. The attacks may affect activity Occurs more than 1 time in a week Between 60%-80% More than 30% Severe persistent Often continuous and may limit physical activity Occurs frequently Less or equals to 60% More than 30% Forced Expiratory Volume got in the first second= FEV1 III. Pathophysiology and Pathology. Asthma pathophysiology is immensely complex since it does not entail a single factor, rather it constitute a number of factors that come into play. It entails an inflammatory process of the airways, hypersensitivity, obstruction, plus other factors. Asthma often has an acute phase and a chronic phase. Hence, the processes involved in the pathophysiology of asthma could be acute, sub acute or chronic in nature depending on genetic and environmental conditions. Also, the presence of certain immunological components like mononuclear cells affects asthma. Asthma also got mucus hyperplasia, airway remodeling and epithelial desquamation occurring (Mills 2006, p.20). A. Inflammation of the Air ways. Hypersensitivity often becomes exaggerated in response to certain exogenous and endogenous stimuli. In here, there got direct stimulation of the given airway smooth muscles leading to bronchoconstriction and increased mucus secretion lining the airway. It is hence vital to note the severity of any given asthma as it becomes directly linked to the degree of obstruction the patient is experiencing after the bronchoconstriction (Mills 2006, p.21). The principle cells that can be identified during an inflammatory process include; mast cells, macrophages, eosinophils, and epithelial cells. Others cells t The T lymphocyte often releases interleukins responsible for the differentiation and maturation of B lymphocytes to produce antibodies. Other cells responsible for the chronicity of asthma include endothelial, epithelial cells and fibroblasts. Furthermore, other factors which contribute to inflammation include selectins and integrins. This cell derived mediators are vital in transforming the airways to have soft or smooth tones. Therefore, chronic inflammation often becomes associated with prolonged and increased bronchial hyper-responsiveness. These often result in bronchospasms that become characterized by difficulties in breathing plus wheezing. Patients often cough on exposure to allergens. Coughing is a reflex action to expel the allergens. Other triggers of coughing entail viruses, environmental irritants, cold air and exercise. B. Obstruction of the airflow. Air way obstruction is often a feature seen in asthma cases. Upon the settling of an allergen or irritant on the airways, a number of factors contribute to cause bronchospasms. Around the airway passages, there are a number of cells like eosinophils and mast cells that produce histamines that result to bronchoconstriction. Often in acute inflammation process, there may be edema that may lead to narrowing of the airway causing wheezing and bronchoconstriction (Mills 2006, p.23). Furthermore, airway remodeling may occur in formation of plugs. Bronchoconstriction often is an acute sign of acute asthma. The exposure often results in release of immunoglobulin responsible for facilitating the constriction process. Moreover, air way edema often occurs between 6 to 24 hours on exposure to a given allergen and therefore termed late asthmatic response. The formation of mucus plugs takes place several weeks after as a result of production of exudates serum proteins plus dead cells from inflamed airways. In chronic inflammation of the airways, some air way modeling often occurs and results to some extent to reversibility of the airway obstruction. Airway obstruction remains dangerous since it often affects airflow to the alveoli. This then results to breathing difficulties in an attempt to compensate for the impaired breathing. When asthma gets left untreated for long, often results to chronic loss of lung function plus also contribute to a condition called chronic obstructive lung disease. C. Bronchial Hyper-responsiveness. Bronchial hyper-responsiveness often remains as a response to the airway reacting acutely to allergens. These often result to production of waste cells or mucus plug. There is often hyperinflation to compensate for air obstructions. There is alveolar hypoventilation when the tidal volume becomes close to pulmonary dead space volume. In having an obstructed airway due to hyper-responsiveness, there results in uneven distribution of air. In overall, it results to less gaseous exchange (Mills 2006, p.25). Therefore, the lungs will receive less oxygen and result in poor excretion of carbon dioxide. In asthma, there is often ventilation mismatch. Such patients often can develop respiration acidosis due to excess accumulation of carbon dioxide in the blood stream. Other factors that contribute to the mismatch include mismatch in vasoconstriction. In early stages of obstruction, ventilation at the alveolar often results to prevent hypercarbia. In case of increased obstruction, a lot of carbon dioxide becomes retained in cells. This causes increase in breathing, increased oxygen consumption, plus increased cardiac output in order to compensate for the mixed acidosis. D. Effects of Asthma on the Respiratory System. Respiratory system remains a vital organ in the process of gaseous exchange. Human beings often require oxygen for the normal functioning of the cells. In excretion, carbon-dioxide gets produced. Oxygen often becomes used in metabolic processes resulting in production of energy necessary to run other metabolic processes. Energy often becomes produced from nutrients (Mills 2006, p.44). However, metabolism not only produces energy, but also produces wastes like carbon-dioxide and water. Wastes often need to become eliminated in order to avoid toxic accumulation of the waste products. Toxic wastes are commonly not beneficial to the normal functioning of the body. Hence, the respiration systems role becomes providing oxygen to fuel the metabolic process while it excreted carbon dioxide as a waste product of metabolism. Therefore, in asthma, rate of excretion of carbon dioxide becomes reduced while oxygen entry into the lungs becomes reduced due to the narrowing and obstruction of the airway (Mills 2006, p.47). E. Gross appearance. The lungs are over distended because of over- inflation. On pathological observation of the surface of the bronchioles often got viscid mucus plugs occluding it (Mills 2006, p.28). F. Microscopic appearance. 1. The mucus plugs contained degenerated or normal respiratory epithelium. 2. Sputum contains numerous eosinophils plus diamond shaped crystals called charcot-leyden crystals. 3. Bronchial epithelium got thickened basement membrane, some sub mucosa edema and inflammatory infiltrates made of lymphocytes, eosinophils and plasma cells. IV. Diagnosis of asthma. A. Clinical history of asthma. Asthma symptoms include recurrent wheezing, chest tightness, breathing difficulties and many more. In toddlers plus children, additional symptoms could include faster breathing of more than 60 bpm (breathes per minute) for the new born and over 40 bpm for toddlers. Furthermore, other constitutional symptoms may include common coughs worsened during playing, inactive participation in physical activities, plus occasionally a clear cough accompanied by a runny nose (Mills 2006, p.62). The symptoms often remain complex. Therefore, there got the need to look deeper into factors like genetics, environmental factors and host factors. One should always ensure that the symptoms become well connected so as to avoid mistaking some normal coughs for asthma. Aggravating factors to asthma states may encompass dust, chemical irritants and others. B. Physical examination. Examination of an asthma patient involves the normal protocol of examination of the respiratory system. One can examination the upper air ways including the throat and the nose to ascertain the integrity of it. Doctors often use stethoscopes to listen to chest sounds and ascertain their vocal fremitus. Often in an asthmatic patient, one may be able to hear rhonchi, some crepitations and even some transmitted sounds. Wheezing plus the production of high pitched sounds on respiration denotes some signs of the disease. In addition, in severe cases, patients may exhibit signs of respiration distress. Other signs of respiration distress exhibited by asthma patients include flaring of ala nasa and lower wall chest in drawing in children. Upon skin examination, the patient may be found with some allergic conditions like hives plus eczema (Mills 2006, p.70). C. Investigations to confirm the diagnosis of asthma. The following findings are usually indicative of asthma: 1. A peak respiratory rate which varies with more than 20 diurnally. 2. If peak respiratory rate varies by more than fifteen in 6 minutes or more after sustained exercise. 3. If peak respiration rate increases by more than fifteen percent after one becomes injected or inhaled a short acting beta two agonist. 4. If one got increased bronchial hyper-responsiveness to histamine, exercise and mannitol, one could still be said to be an asthmatic. 5. In case of spirometry, when the forced expiratory volume in one second becomes greater than twelve percent after diagnosis of broncho-dilation, could also be confirmatory to diagnosis of asthma. 6. Chest X-ray could depict a hyper inflated lung. V. Management of asthma. A. Goals in management of asthma. 1. Ensure that the treatment or management accorded abolishes the symptoms and lets the person lead a normal life in school or work or in whatever place the guy is. 2. Management of asthma should be aimed towards restoring the normal functions of the lung. 3. Management often becomes supposed to allow for normal bronchial development and growth. B. Treatment and Prevention. The long term management of an asthmatic patient involves preventing the triggers and the risk factors involved in aggravating the condition. Medications often proved successful in relieving some of the symptoms of asthma and keeping them under control. Moreover, medication for asthma often becomes given in accordance to age and severity to minimize or eliminate the symptoms of asthma that cause discomfort in the patient’s life (Mills 2006, p.87). In addition, preventive measures often become used to prevent recurrence of certain symptoms. Long term prevention often becomes easy to initiate since it often becomes part of the patient’s life. Long term prevention is also desirable since the patients can give themselves the medications. Furthermore, the use of fast relieving inhalers containing salbutamol could become used in treating acute asthmatic conditions. In addition, the fast relieving inhales also called bronchodilators often assist in cases of bronchoconstriction. In cases of asthma triggered by allergies, one could get medications to those allergies. Long term asthma medications often become given for recurrent and persistent cases. Example of medications taken daily include: inhaled corticosteroids, leukotriene modifiers, long acting beta agonists, combination inhalers and theophylline. These medications get taken daily or weekly as per prescribed by the physician. In short asthma attacks, short acting medications become more preferable than long acting drugs to alleviate the severity of the condition (Mills 2006, p.78). Hence, short acting drugs used for quick relief then include: short acting beta agonist, intravenous and oral corticosteroids, plus anticholinergics like ipratropium. The short acting agents in asthma management are mainly bronchodilators used in acute asthma attacks to open the airways. In addition, some drugs work to reduce the inflammatory process. Other drugs may be used to treat specific allergies that exacerbated the given asthma. VI. Conclusions and Summary. Asthma hence remains as a disease affecting the respiratory system leading to obstruction of the bronchial tubes leading to gaseous exchange mismatch and subsequent symptoms. In any normal respiratory system, air ought to be taken via the nose or mouth, down the trachea to the bronchioles and alveoli in the lungs. Furthermore, carbon dioxide often leaves via the same route. In asthma, individuals often have an inflamed airway. The air passages become swollen and produce mucus fluid. In addition, hypersensitivity in asthma could also be induced by dust, cigarette smoke or exercise (Mills 2006, p.16). As the hypersensitivity increases, so does the muscles surrounding the air passages tighten causing bronchoconstriction. The interplay between the contracting smooth muscles plus inflammation often results to difficulties in breathing. Host, genetics, dietary plus family history among others plays a role in influencing the etiology of the disease. Asthma can be managed for a long time or a short time depending on the type and severity. Treatment can be done at the hospital or at a personal level. Medications often reduce the degree of the symptoms the patient gets. Bibliography Mills, T., 2006, Asthma: causes and mechanisms of an epidemic inflammatory disease, New York: Lewis Publishers. Read More