Which findings confirm a diagnosis of chronic obstructive pulmonary disease (COPD)? Select all that apply.

The confirmation of a diagnosis of chronic obstructive pulmonary disease (COPD) relies heavily on specific respiratory function tests, particularly the assessment of airflow limitation. Post-bronchodilator results refer to measurements taken after administering a bronchodilator, which is a critical step in evaluating lung function. In COPD, there is a characteristic pattern of airflow obstruction that is not fully reversible even after bronchodilator therapy. Therefore, demonstrating persistent airflow limitation (usually recorded as a reduced FEV1/FVC ratio) after the use of bronchodilators directly supports the diagnosis of COPD.

While smoking history is an important risk factor for COPD, it alone does not confirm the diagnosis. Oximetry results can indicate oxygen saturation levels but do not directly assess lung function, making them insufficient for diagnosis. Similarly, electrocardiograph results may provide information about the heart but are not specific to diagnosing pulmonary diseases like COPD. Hence, the post-bronchodilator results are the primary findings that confirm a diagnosis of COPD due to the focus on the evaluation of airway obstruction.