Breathing machine: spirometer

You breathe through a mouthpiece connected to the device. The spirometer records the amount of air you can exhale and the speed of that exhalation. Results help a clinician look for an obstructive pattern, assess breathing symptoms, or compare lung function over time. The reading is one part of an assessment and does not by itself name a diagnosis.

Wear comfortable clothing and follow the clinic's instructions about medicines, meals, and smoking before the appointment. During spirometry, seal your lips around the mouthpiece, breathe as instructed, and give a strong, sustained exhalation when asked. Several attempts may be needed so the team can judge the consistency of the result. Tell the clinician if you feel dizzy or uncomfortable.

Spirometry is a planned test, not emergency treatment. Seek urgent help for severe breathlessness, chest pressure, fainting, blue or grey lips, or sudden worsening symptoms. Contact the testing clinic if you have an acute respiratory infection or feel too unwell to perform the manoeuvres safely; they may advise a different appointment.

Ask what question the test is intended to answer, which medicines you should take or pause, and when you will discuss the result. Ask whether another lung test is needed if symptoms and the reading do not match.