Chronic obstructive pulmonary disease (COPD) is preventable disease that has a detrimental effects on both the airway and lung parenchyma (Nazir & Erbland, 2009). COPD categorises emphysema and chronic bronchitis, both of which are characterised by a reduced maximum expiratory flow and slow but forced emptying of the lungs (Jeffery 1998). The disease has the one of the highest number of fatalities in the developed world due to the ever increasing amount of tobacco smokers and is associated with significant morbidity and mortality (Marx, Hockberger & Walls, 2014). Signs and symptoms that indicate the presence of the disease include a productive cough, wheezing, dyspnoea and ...view middle of the document...
, 2001). It has been found that 12% of moderate and 26% of heavy smokers will develop a form of COPD in the later stages of life (Larsson, 2007). These statistic are shown to increase significantly as those who smoke age with approximately 50% of smokers diagnosed with COPD by the age of 75 (Larsson, 2007). It has been found that 90% of chronic bronchitis patients have developed the disease because of a long-standing history of tobacco smoking (TXT). Other important factors include air pollution, occupational hazards, advanced age, airway hyper-responsiveness, diet, alcohol consumption and heredity (Edelman et al., 1992). Although mortality rates for COPD have decreased due to the progression of medical care, COPD currently has one of the highest mortality rates throughout the developed world (Viegi et al., 2001). It currently ranks as the third highest burden of disease in Australasia and the ninth highest worldwide (Australian Institute of Health and Welfare, 2013). The number of people with COPD is predicted to rapidly increase globally over the coming decades as the tobacco epidemic continues (Viegi et al. 2001). COPD also places a large economic burden on the world with the costs of treatment and care as well as the days of work lost (Viegi et al. 2001).
Respiratory system anatomy and physiology:
The respiratory system is comprised of the respiratory tract, chest wall, pulmonary circulation and the central nervous system (Person & Mintz, 2006). The respriatory tract consists of the nasopharynx and the oropharynx that works as a filter and humidifier for the inspired air (Person & Mintz, 2006). The trachea, lined with respiratory epithelium containing goblet cells that produce muscus which traps particles in the air, follows on from the nasopharynx and oropharynx (Blackler, Jones & Mooney, 2007). The trachea bifurcates at the carina into the left and right primary bronchi that each subdivide into the secondary, then tertiary bronchi which all form part of the pulmonary vasculature (Person & Mintz, 2006). Each of the tertiary bronchi are different bronchopulmonary segments that are all individually supplied by a separate branch of the pulmonary artery (Person & Mintz, 2006). Further subdivision occurs to form the bronchioles that assist in the capturing of smaller foreign particles and contain lymphatic channels (Person & Mintz, 2006). Inferior to the bronchioles is the alveoli which contain macrophages, neutrophils and eosinophils that form part of an inflammatory response if a pathogen is detected (Person & Mintz, 2006). Alveoli are connected to one another by capillaries and small holes called pores of Khon (Al-Tubaikh, 2010). Tissue inferior to the carina forms the parenchyma of the lungs, the small airways are those less than two millimetres in diameter whilst the remaining airways are considered large (Person & Mintz, 2006).
On inspiration the diaphragm, innovated by the phrenic nerve, contracts, expanding the thoracic...