What should you know about a BTL spirometer?

During spirometry, you breathe into a mouthpiece while the device records airflow. The clinician may compare the pattern with expected values based on factors such as age, height and sex. The test can help assess wheeze, cough, breathlessness and suspected airway narrowing, but the tracing is interpreted alongside your history, examination and sometimes a response after an inhaled medicine.

Follow the clinic's instructions about inhalers, as some medicines may need to be paused and others should be taken as usual. Wear comfortable clothing, avoid a heavy meal immediately beforehand and tell the operator if you feel unwell. You will be coached to seal your lips around the mouthpiece and make a strong, sustained breath out; several attempts may be needed for a reliable result.

Tell the operator immediately if testing causes chest pain, severe breathlessness, dizziness 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. Arrange medical review for breathlessness that is worsening, occurs at rest or interrupts sleep.

Ask which inhalers to use before testing, whether the effort was adequate, what the pattern suggests and whether repeat or additional lung testing is needed.