Which of the following would NOT contraindicate a pulmonary function test?

The use of bronchodilators before a pulmonary function test is generally not a contraindication. In fact, the administration of bronchodilators can be an important part of the test, particularly in assessing reversibility of airway obstruction in individuals with conditions like asthma or COPD. The test can be conducted before and after the bronchodilator is given to measure improvements in lung function, helping to inform diagnosis and management.

In contrast, recent respiratory infections, smoking close to the time of testing, and being in severe respiratory distress all present situations that might compromise the accuracy and safety of the test. A recent infection could affect lung function measurements, while smoking can acutely alter airway dynamics and impact PFT results. Severe respiratory distress poses an immediate risk to the patient during testing, as it may worsen their condition or lead to adverse events.

Thus, the use of bronchodilators is not only acceptable but also beneficial in many cases, making it the option that does not contraindicate performing pulmonary function tests.