Spirometry with BDR explained

BDR stands for bronchodilator response. You blow into a spirometer to record airflow, receive an airway-opening medicine, and repeat the test after the instructed waiting period. The team compares the two recordings rather than relying on a single breath.

A noticeable response may help explain variable airway narrowing, including patterns seen with asthma. Results can also be unchanged, and that finding does not settle the diagnosis alone. Symptoms, examination, smoking history, previous infections, medicines, and test quality remain relevant.

Ask the clinic exactly how to prepare and whether any inhaler needs to be delayed. Continue other prescribed medicines unless told otherwise, and report allergies, heart rhythm problems, pregnancy, or a recent chest infection.

Perform both sets of blows with a tight mouth seal and a rapid, sustained exhalation. Rest if you feel dizzy or exhausted. The bronchodilator can briefly cause shakiness, a dry mouth, or a faster heartbeat; tell the clinician if these effects are uncomfortable or do not settle.

Call emergency services for extreme breathlessness, inability to speak normally, blue or grey lips, collapse, confusion, or severe chest pressure. Seek prompt clinical advice if your breathing keeps deteriorating or your prescribed reliever gives less help than usual.

Ask what changed between the recordings and whether the comparison is sufficient for interpretation. Check when to resume medicines that were paused, whether symptoms need monitoring, and what follow-up test or treatment review is recommended.