Acute Exacerbation of Chronic Obstructive Pulmonary Diseases: What is the impact of bronchodilators, corticosteroids and antibiotics?

Relevant articles published between 1966 and July 1st, 2002, were retrieved from Medline using the index terms “chronic obstructive pulmonary disease”, “chronic bronchitis” combined with “acute exacerbations” as well as specific terms relating to various interventions such as “steroids”, “bronchodilators”, “anticholinergics”, “antibiotics”, and “mucolytics”. The Cochrane control trials register until the end of the year 2001 was also searched. Well conducted, randomized, controlled trials constitute strong or Level-A evidence; well designed controlled trials without randomization including cohort and case control studies constitute Level-B or fair evidence; non-randomized clinical trials, observational studies constitute Level-C; and expert opinion, case studies, and before and after studies are Level-D or weak evidence. These ratings appear as roman numerals in parenthesis after each recommendation in these guidelines.