What should you know about expiratory spirometer?

During spirometry, you breathe into a mouthpiece connected to a spirometer. The device records the volume of air you exhale and how quickly it leaves your lungs. The clinician may ask for a normal breath and then a full, fast effort after filling your lungs. Results are compared with expected values and with your symptoms, examination and medical history. The test can help assess airflow problems such as asthma or chronic obstructive lung disease, but a single reading does not explain every breathing complaint.

Wear comfortable clothing and follow the clinic's instructions about meals, smoking and inhalers. Tell the team about recent surgery, chest pain, dizziness or an infection, and ask whether any inhaler should be held. Sit upright, seal your lips around the mouthpiece and follow the technician's coaching. Several efforts may be needed for a dependable result. Do not turn home readings into a diagnosis; record symptoms and the circumstances around each measurement.

Stop and tell the clinician if the test causes marked dizziness, chest pain or severe breathlessness. Seek urgent help for breathing difficulty that is severe or worsening, blue lips, fainting or confusion. A spirometer reading should not delay emergency care when symptoms are serious.

What do my airflow and exhaled-volume results show? Could my inhaler or recent illness affect the test? Do I need repeat spirometry or another assessment? Which symptoms should prompt urgent help?