What should you know about normal lung capacity spirometer?

Spirometry measures how much air you breathe out and how quickly you can move it. The clinician compares the tracing with expected values for factors such as age, height and sex, then checks whether the test was performed well. A normal result makes some forms of persistent airflow obstruction less likely, yet asthma symptoms can vary over time and may not appear during the appointment. Chest wall problems, heart conditions, anaemia, anxiety, infection or poor fitness can also cause breathlessness without changing spirometry in the same way. The result is one part of an assessment, rather than a complete measure of lung health.

Keep the report and ask which values were normal and whether the effort was acceptable. Describe when breathlessness, cough or wheeze occurs, including triggers, night symptoms and activity limits. Follow any inhaler plan already prescribed, and do not change regular medicines solely because the tracing looks normal. If symptoms continue, a clinician may consider repeat testing when symptoms are present, bronchodilator testing or another assessment. Learn more about the [Spirometer](/technology/spirometer/) and [Spirometry](/treatments/diagnostics-and-screening/spirometry/).

Seek emergency care for severe or rapidly worsening breathlessness, blue or grey lips, fainting, confusion, or difficulty speaking because of lack of air. Arrange prompt medical review for new breathlessness, coughing blood, chest pain, high fever, or symptoms that are limiting ordinary activity. A normal test should not delay assessment when symptoms are sudden, intense or worsening.

Which spirometry values were measured, and was the test quality satisfactory? Could my symptoms be intermittent or caused by something outside the airways? Do I need repeat testing or another examination? What changes should prompt an urgent review?