inflammation and severe limitation of airflow in and out of the lungs. COPD is a nonspecific umbrella term that encompasses a variety of pulmonary diseases, the main three being chronic bronchitis, emphysema and asthma I COPD (Mannino, 2002). It is characterized by airflow limitation due to the gradual loss of effective breathing. At first no symptoms or mild symptoms are present however as the disease progresses, shortness of breath, wheezing, chest tightness, ongoing (chronic) cough often with a lot of mucous occurs. As it worsens, breathing requires much more energy and it can get harder to complete simple activities or to exercise, this may lead to fatigue, weight loss and muscle loss. Exacerbations and comorbidities contribute to the overall severity of the disease to individual patients. Patients present with common problems like dyspnoea(laboured breathing), chronic cough and sputum production. Some less common symptoms include wheezing and chest tightness. Risk factors include smoking, air pollution, low birth weight, recurrent infections and low economic status. Chronic Bronchitis is defined as an inflammatory change leading to muscularly dysfunction and increased goblet cell secretion and numbers. This damage inside the airways causes the lining to swell thicken. The combination of bronchoconstriction and mucus hyper secretion causes a persistent cough to develop in bronchitis as the body tries to expel this excessive mucus. The airway constriction and mucus leads to wheezing typically heard during expiration. When airway obstruction is occurring, alveolar hypoxia may also be occurring because oxygen is not getting through to the alveoli efficiently. Some symptoms include an ongoing cough, shortness of breath and frequent respiratory infections. Emphysema is a disease that destroys some alveolar walls and increases airspaces inside the lungs that provide less surface area for oxygen absorption from the atmosphere (Mannino, 2002). Airways and air sacs lose their flexibility making it harder for them to expand and contract. Symptoms include wheezing shortness of breath and chest tightness. Asthma is the least common respiratory disease present in COPD relative to chronic bronchitis and emphysema. It is a chronic inflammatory disorder of the airway in which many cells and cellular elements play a role. Recurrent episode of wheezing, breathlessness and coughing are some signs and symptoms. The American Thoracic Society (ATS) COPD guidelines composed definitions for asthma, chronic bronchitis, emphysema, COPD and airflow obstruction and classified eleven separate disorders, as seen in the figure below. These guideline also recognised COPD as a respiratory disease where irreversible airflow interference is the underlying aspect, allowing COPD to be more clearly identified. Below is a non-proportional Venn diagram clearly distinguishing the eleven separate disorders in patients and the ways in which they overlap. (Gibson and Simpson, 2009)>