Respiratory System of Human Body - Essay Example

?Topic: Respiratory Respiratory system proves to be one of the most essential parts of human bodies since it involved the inhale and exhaleof air thereby allowing oxygen to enter the body and carbon dioxide to exhale out of the body. Thus an understanding of the system and its functions is also necessary. This is primary because there are several factors that may affect the properties and functioning of the system. This particular study focuses on such an understanding and focuses on the structure and function of the respiratory system and the associated diseases and diagnosis as well. Introduction: In terms of physiology, the process of respiration is described as an “interchange of gases between an organism and its environment” (Davies, Moores & Britton, 2003, p.2). This process in human beings is referred to as breathing. This involves the roles of the lungs that are structures in human bodies enabling the process of breathing. In order to understand the functions and operations of the respiratory system, it is necessary to have an understanding on the description and functions of the macroscopic and the damages in these structures that can cause disease in the body. The primary role of the respiratory system is to provide oxygen to the body such that the supply of oxygen may be continuous. Also, carbon dioxide from the body is removed through this process, hence making the process and the system all the more important (Davies, Moores & Britton, 2003, pp.2-3). The present study focuses on an understanding of the structure of the respiratory system, the functions of the respiratory system, the factors affecting gas diffusion, the pathological factors reducing diffusion rate, as well as the respiratory diseases. 1. Structure of the Respiratory System: There are two fundamental parts of the respiratory system- one portion conducting air and another exchanging gas. There are several passageways in the air conducting portion thus allowing air to pass through. The exchange of gas is performed by the lungs. The different major parts of the respiratory system include the nasal cavity, the oral cavity, the pharynx, the epiglottis, the larynx, the trachea and bronchi, the bronchioles and the alveoli. The nose and the mouth allow the air to enter the body which is then passed to the pharynx joining to the larynx. The larynx opens up into the trachea which a short duct wide in structure. Cartilage reinforcements occur on the trachea and bronchi and bronchioles are formed from the smallest bronchi, leading the bronchioles towards the alveoli (Chiras, 2011, pp.152-154). The structure of the respiratory system has been presented in the following illustration: Figure 1: The Structure of Respiratory System (Laurien, 2013). 2. Factors Affecting Gas Diffusion: Exchange of gas within the body is performed by the process of diffusion. The process of gas diffusion may be illustrated through the diagram on the left. Figure 2: Gas Exchange in the Lungs (Respiration, n.d.). The first law of definition given by Fick provides the factors that affect the process of gas diffusion. The factors affect the process of gas diffusion through membranes in the system that is permeable in nature. This is given by the following definition (Rankin, Duggan & Pitcher, 1983, p.41): M = KA ?P/x Where M = amount of gas diffusing per unit time (mmol min-1), K = Krogh’s diffusion constant (nmol s-1 kPa-1), A = area of membrane (mm2), ?P = difference in partial pressure of gas on each side of the membrane (kPa), x = thickness of membrane (µm). It is necessary to mention in this regard that the gas diffusion is normally measured in terms of its amount. However, the “driving force is the difference in partial pressure” (Rankin, Duggan & Pitcher, 1983, p.41). 2.1. Pathological Conditions Affecting Diffusing Capacity: The diffusion capacity for carbon monoxide is calculated by the following formula (Modak, 2008, p.114): Diffusing capacity for carbon monoxide = Carbon monoxide uptake / Alveolar carbon monoxide The normal capacity of diffusion has been obtained to be 25 mL/minute/mm Hg. This value may be affected or changed in three different cases. One is when there is an alteration in the effectual surface area of the membrane through which the gas passes. Secondly, it may be altered when the physical properties of the membrane gets altered. Thirdly, changes in the uptake by the hemoglobin cause alterations in this value of diffusing capacity. Some of the factors that have an effect on the surface area of the membrane include the size of the body, the volume of the lung, posture and pathology of the lung which is also referred as emphysema. Diffusion capacities may be reduced if the body suffers from chronic failure of the heart and pulmonary edema. This happens due to the changes occurring in the properties of the membrane as a result of these diseases. The concentration of hemoglobin in the system has the ability to affect the uptake of carbon dioxide which is also affected by the transit time of the capillary. Some of the other pathological factors affecting the capacity of diffusion include age, sex, racial origin, and smoking (Modak, 2008, p.114). 2.1.1. Emphysema: Emphysema is a disease of the lung that occurs on a long term basis. It is a progressive disease and occurs “when the alveolar walls are destroyed along with the capillary blood vessels that run within them” (Schiffman, 2011). As a result of this, the total area of the lungs gets reduced where blood and air normally joins together, thereby restricting the effective transfer of oxygen and carbon dioxide in the body. The lungs gradually get destroyed as a consequence of this disease. The oxygen concentrations are then unable to be maintained by the lungs. The rate of breathing increases allowing the body to compensate the concentrations of the oxygen required by the body (Schiffman, 2011). The disease of the lung may be represented through the following diagram: Figure 3: Emphysema (Thompson, 2010) The symptoms of this disease generally include shortness of breath, cough, excess mucus, blood obtained in cough, pain in the chest, cyanosis where a bluish tinge occurs in the skin and membranes of the body, and digital clubbing where the fingers of an individual turn into a drumstick shape. Inflammation, either acute or chronic in nature is also associated with emphysema. The disease normally results in an abnormal swelling of the alveoli. The walls of the alveoli, as a result, tend to be destroyed, thereby enlarging the spaces through air passes. Smoking has been mostly concerned as the major cause leading to emphysema. However there may be other substances inhaled in the body that can cause emphysema as well. Moreover there are certain types of the diseases depending on the variations in their occurrences. Centrilobular emphysema is the most common type and involves the bronchioles and the alveolis. Panlobular emphysema normally occurs as a result of the deficiency of alpha-1 AT. Paraseptal emphysema generally affects the distal part of acinus, alveolar sacs, and alveoli. Another type is the irregular emphysema causing scars in the lungs (Green, 2007, pp.22-36). 2.1.2. Pneumonia: Pneumonia is a disease that causes infection in one or both of the lungs in human bodies. Generally the causes for the disease include attacks of bacteria or viruses, or even fungi. As a result of the disease, the air sacs or alveoli of the lungs get inflamed. Fluid or pus fills up these sacs leading to cough containing a greasy substance called phlegm. The cough is also accompanied by fever, chills and troubles in breathing (What is Pneumonia?, 2013). The difference of the lungs in its normal state and when affected by pneumonia may be illustrated by the following diagram: Figure 4: Pneumonia (Bronchitis and Pneumonia, 2007). The disease has also been classified into four different types – Community acquired pneumonia that is acquired by the body at any point of time, Perioperatively associated pneumonia, Health-care associated pneumonia, and Hospital acquired pneumonia. Individuals with infections in their upper respiratory tract are more prone towards getting affecting by pneumonia (Fein, Grossman & Ost, 2006, pp.15-22). 3. Restrictive versus Obstructive Pulmonary Disease: The restrictive and obstructive pulmonary diseases may be illustrated through the following figure: Figure 5: Obstructive versus Restrictive Lung Disease (Zubieta, n.d.). Obstructive lung disease causes shortness of breath among the affected individuals. This happens since the system encounters problem in expiring out the necessary amount of air from the lungs. Restrictive lung disease is different from the obstructive lung disease since in this case, the lungs cannot be fully filled with air. Thus the lungs cannot fully expand as is required for the body (Johnson, 2012). 3.1. Diagnostic Methods: For the diagnosis of obstructive lung diseases, physical examination is done to detect any changes in the physical patterns or in the color of the skin, or any alterations in the lips, fingers. Breathing is checked to see if it’s normal. Then spirometry is used which are the pulmonary function tests. The volume and force of air when it is expired out of the lungs is measured by this method. Thus through this test, any obstruction in the passage of the air can be detected, detecting the possibility of a disease at an early stage. Also, tests are conducted to obtain the ability of the lungs to pass oxygen and carbon dioxide across the system. These tests include Arterial Blood Gas, Pulse Oximetry Test, Carbon Monoxide Diffusing Capacity, and exhaled breath. Imaging tests are performed including X-rays of the chest and computed tomography. Also there are tests for the blood and the bronchioles as well for the diagnosis of the disease (Chronic Obstructive Pulmonary Disease, 2013). For the diagnosis of the restrictive pulmonary disease also, the pulmonary function tests are conducted that help in obtaining a pattern “with a reduced force vital capacity (FVC) and forced expiratory volume in 1 second (FEV1) and normal FEV1/FVC ratio” (Feigin, 2004, p.313). Conclusion: From the above study, the structure and he functions of the respiratory system could be realized. It could be obtained that there are different diseases of the lungs and accordingly there are diagnostic measures depending on which the diseases may be treated. However in most cases the damages to the lungs are significant that may be the results of factors like smoking as well. Gas diffusion is the most important role of the respiratory system. However the study has obtained that there are several pathological and associated factors that can significantly affect the diffusing capacity of the system and hence affect the exchange of gases. Therefore it can be concluded from the study that in order to have the respiratory system function normally, the different factors need to be considered and realized effectively and negative effects need to be avoided, since intake of oxygen and release of carbon dioxide from the body is highly essential for living. References Bronchitis and Pneumonia (2007), medtogo, available at: http://www.medtogo.com/bronchitis-pneumonia.html (accessed on January 11, 2013) Chiras, D. (2011), Human Biology, Massachusetts: Jones & Bartlett Learning Chronic Obstructive Pulmonary Disease (2013), nytimes, available at: http://health.nytimes.com/health/guides/disease/chronic-obstructive-pulmonary-disease/diagnostic-tests.html (accessed on January 12, 2013) Davies, A.S., Moores, C. & R. Britton (2003), The Respiratory System, Amsterdam: Elsevier Health Sciences Feigin, R.D. (2004), Textbook of Pediatric Infectious Diseases, Volume 1; Volume 355, Amsterdam: Elsevier Health Sciences Fein, A., R. Grossman & D. Ost (2006), Diagnosis and Management of Pneumonia and Other Respiratory Infections, 2nd Ed., New York: Professional Communications Green, R.J. (2007), Natural Therapies for Emphysema and COPD: Relief and Healing for Chronic Pulmonary Disorders, Vermont: Inner Traditions / Bear & Co Johnson, K. (2012), Obstructive and Restrictive Lung Disease, webmd, available at: http://www.webmd.com/lung/obstructive-and-restrictive-lung-disease (accessed on January 12, 2013) Laurien, L. (2013), The Respiratory System – Glossary, available at: http://www.ama-assn.org/ama/pub/physician-resources/patient-education-materials/atlas-of-human-body/respiratory-system-structure.page (accessed on January 9, 2013) Modak, R.K. (2008), Anesthesiology Keywords Review, Philadelphia: Lippincott Williams & Wilkins Rankin, J.C., Duggan, R.T. & T.J. Pitcher (1983), Control Processes in Fish Physiology, New York: Springer Respiration (n.d.), phy-astr, available at: http://hyperphysics.phy-astr.gsu.edu/hbase/biology/respir.html (accessed on January 10, 2013) Schiffman, G. (2011), Emphysema, medicinenet, available at: http://www.medicinenet.com/emphysema/page2.htm#what_is_emphysema (accessed on January 11, 2013) Thompson, E.G. (2010) Emphysema, webmd, available at: http://www.webmd.com/lung/emphysema (accessed on January 11, 2013) What is Pneumonia? (2013), NIH, available at: http://www.nhlbi.nih.gov/health/health-topics/topics/pnu/printall-index.html (accessed on January 11, 2013) Zubieta, P. (n.d.), Chapter 13: Mechanics of Breathing and Lung Disorders, zuniv, available at: http://www.zuniv.net/physiology/book/chapter13.html (accessed on January 11, 2013) Read More