COPD exacerbation: Definition: Exacerbation of COPD is defined as an acute episode, characterized by the worsening of the patient’s respiratory symptoms that is beyond normal daily variations and that will eventually lead to a change in his medications. Those having 2 or more exacerbations per year are known as “frequent exacerbators”. Precipitating factors: 1) Respiratory tract infections – viral or bacterial. Most common cause. There may be an increased bacterial burden in the lower airways or new strains of bacteria are acquired during an exacerbation. Commonly implicated viruses include rhinovirus, respiratory syncytial virus, coronavirus and influenza virus. 2) Air pollution. 3) Interruption of maintenance therapy. 4) Unknown causes – 30% cases. Diagnosis: Diagnosis should be made clinically whereby the patient complains of an acute aggravation of his symptoms out of proportion to his day to day variations. Assessment: Medical history: 1...