Asthma Essay -- essays research papers fc

Asthma is a disorder of the respiratory system in which the passages that enable disseminate to pass into and out of the lungs periodic solelyy narrow, causing coughing, wheezing, and shortness of intimation. This narrowing is typically temporary and reversible, but in severe attacks, asthma attack attack may result in death. Asthma most commonly refers to bronchial asthma, an inflammation of the airways, but the term is also used to refer to cardiac asthma, which develops when fluid builds up in the lungs as a complication of inwardness failure. This article focuses on bronchial asthma.More than 17 million Americans catch from asthma, with nearly 5 million cases occurring in children under age 18. In the United States, asthma causes nearly 5,500 deaths each year. Asthma occurs in males and females of all ages, ethnic groups, and socioeconomic levels. For reasons not completely understood, asthma is generally to a greater extent common in poor urban neighborhoods, in cold cl imates, and in industrialized countries.Among all Americans, the prevalence of asthma increased more than 60 percent between 1982 and 1994, in particular among children. Deaths from asthma increased more than 55 percent from 1979 to 1992. Scientists suspect that increased exposure to second-hand cigarette smoke, growing populations in polluted city centers, and new housing that is poorly ventilated throw to the increase in asthma cases.BreathingEvery cell in the human body requires group O to function, and the lungs make that oxygen available. With every breath we take, air travels to the lungs by means of a series of tubes and airways. After passing through the mouth and throat, air moves through the larynx, commonly known as the juncture box, and then through the trachea, or windpipe. The trachea divides into two branches, called the right bronchial tube and the left bronchus, that connect directly to the lungs. Air continues through the bronchi, which divide into littler and smaller air passages in the lungs, called bronchioles. The bronchioles end in clusters of tiny air sacs, called alveoli, which are surrounded by tiny, thin-walled subscriber line vessels called capillaries.Here, deep in the lungs, oxygen diffuses through the alveoli walls and into the blood in the capillaries and gaseous waste products in the bloodmainly carbon dioxidediffuse through the capillary walls and into the alveoli. But if something prevents the oxygen from reaching t... ...ng, may provoke hyperventilation, a rapid inhalation of oxygen that causes the airway to narrow. In asthmatics, hyperventilation often results in an attack. Many asthmatics are especially sensitive to physical exercise in cold weather.Research suggests that contractable factors may increase the risk of developing the disorder. Children with a family history of asthma are more likely to develop asthma than other children. notwithstanding this apparent genetic link, many people without a family his tory of asthma develop the disorder, and scientists continue to investigate additional causes.TreatmentPhysicians typically mention asthma by looking for the classic symptoms episodic problems with breathing that acknowledge wheezing, coughing, and shortness of breath. When symptoms alone fail to establish a diagnosis of asthma, doctors may use spirometry, a test that measures airflow. By comparing a perseverings normal airflow, airflow during an attack, and airflow after the application of asthma medicinal drug, doctors determine whether the medicine improves the patients breathing problems. If asthma medication helps, doctors usually diagnose the condition as asthma.Bibliographywww.scienceworld.com