What should you know about dynamic spirometry?

You breathe into a spirometer through a mouthpiece. The device records the amount of air you move and the speed of your exhalation. You may repeat the manoeuvre several times, sometimes before and after an inhaled medicine. Results can help assess conditions such as asthma, COPD, bronchiectasis, or an ongoing cough, but they are interpreted alongside symptoms and examination.

Follow the clinic's instructions about medicines, food, smoking, and strenuous activity before testing. Wear comfortable clothing and tell the tester if you feel unwell. Sit upright, seal your lips around the mouthpiece, inhale fully, then blow out hard and keep going as instructed. Coughing or poor technique can make a manoeuvre difficult, so rest between attempts.

Tell the clinician immediately if the test causes chest pain, marked breathlessness, faintness, or wheezing that does not settle with rest. Seek urgent help for severe breathing difficulty, blue lips, confusion, or inability to speak in full sentences. A test result alone does not explain sudden respiratory deterioration.

Ask what each result means, whether medicine should be withheld before testing, when results will be reviewed, and whether inhaler therapy or smoking cessation support could help.