Chronic obstructive pulmonary disease , also known as COPD is a chronic lung disease of airflow limitation that is associated with abnormal inflammatory responses and increased mucus production. In COPD there is blockage of the airflow in the passages of the lungs, which results in decreased airflow and exchange. Common symptoms of COPD include a chronic cough and shortness of breath. Two types of COPD exist; emphysema and chronic bronchitis. Emphysema results in the enlargement of air spaces and air trapping in the lungs while chronic bronchitis leads to a persistent cough and excess mucous production. According to the Center for Disease Control and Prevention, the prevalence of COPD in the US is about 34 million individuals.  COPD is the third largest cause of death in in United States and typically occurs in middle age to later years of life. The primary cause of COPD is the use of inhaled tobacco smoke. About half of all smokers show minor changes of COPD in the lungs, while a quarter of smokers who have a long history of chronic smoking will develop the disease. Second hand smoke can also cause COPD. The sooner the patients quits smoking, the less of a chance of they will have of developing COPD.

In a healthy person, oxygen rich air travels through the lungs and enters the bloodstream, providing oxygen to the body. Air enters the body through the nose and mouth then moves into the trachea and bronchial tree, eventually reaching the alveoli.  Alveoli are tiny air sacs that resemble balloons; they inflate when you breath in and deflate partly when you breath out. It is in the alveoli that oxygen rich air enters the bloodstream and carbon dioxide air leaves the bloodstream. In COPD patients the oxygen intake and carbon dioxide output is reduced due to narrowed air spaces and injured alveoli in the lungs. Chronic Bronchitis: will present with narrowed airways, excess mucous, and inflammation.  The narrowing of the bronchial tree due to spasm of muscle surrounding the airways and from an increase in mucus secreted by cells lining the air passages. Excess mucous production and loss of ciliary function causes a reduced ability to remove the excess mucous from lungs, which causes plugging of air spaces with mucous. Inflammation of the cells lining the bronchial wall cause airway edema, which leads to narrowing of the airways. Emphysema: in emphysema there is a destruction of the alveolar walls and the alveoli become less elastic.

Many people do not experience COPD symptoms until they have already had significant damage to their lungs.  A persistent cough is typically the first symptom to develop and shortness of breath with activity develops later in the conditions. COPD is progressive, meaning that it gets worse over time, especially in those who do not quit smoking. Symptoms of COPD include the following: Chronic cough Increased sputum production, with possible change in color and consistency Shortness of breath Wheezing Fatigue Recurrent lung infections Weight loss and cyanosis are later symptoms. Cyanosis is defined as a bluish-purple coloration of the finger, toe, and lips due to decreased oxygen in the blood.

Smoking is the biggest risk factor for COPD. About a quarter of all smokers will ultimately develop the disease. COPD can be caused by the following: Smoking Second hand smoking Environmental irritants Pollution Poor ventilated home Poorly treated previous infections Multiple viral infections

The diagnosis of COPD is most often based off of symptoms, spirometry, lab work and imaging.  Spirometry is a measurement of how deeply you breathe and the amount of air you can force out of your lungs after one second. Spirometry A spirometer reading is most often used to identify COPD.  It involves breathing into a tube attached to a device that measures the amount of air expired on forced expiration in 1 second (FEV1), the total amount of air expired (FEV), and the total lung capacity (FVC). This may be abnormal even when there are few symptoms of the disease. In COPD you will see FEV 1:FVC ratio of less than <0.7 FEV1 less than <80% Chest X-ray Sometimes a chest x-ray can be used to make the diagnosis of COPD.  This will show hyperinflated lungs and an increase in the darkness of the lungs due to the increase in the size of the alveoli. Lab work In many cases there will be an increase of red blood cells Decreased oxygen entering the blood stream means more red blood cells are produced to carry the oxygen that is entering. Sputum culture to detect inflammation and/or infection ABG (arterial blood gas) To detect the ratio of oxygen versus carbon dioxide in the blood Stages of COPD according to American Thoracic Society Stage 1: