What should you know about wedge bellows spirometer?

You breathe through a mouthpiece while the device's bellows move in response to airflow. A clinician may ask for a steady breath, a full inhalation followed by a forceful exhalation, or repeated efforts. The tracing and measurements can show whether air leaves the lungs more slowly or in a smaller volume than expected. Results depend on age, body size, effort, seal, posture, and instructions, so a single effort is not interpreted in isolation. Learn more about the [Spirometer](/technology/spirometer/).

Follow the testing centre's instructions about eating, smoking, exercise, and inhaler use; do not stop a prescribed medicine unless the clinician tells you to. Wear comfortable clothing, use a firm mouth seal, and follow coaching closely. Several attempts may be needed for a usable result. The procedure is described in [Spirometry](/treatments/diagnostics-and-screening/spirometry/).

Tell the operator before testing if you have severe breathlessness, chest pain, recent surgery, fainting, or an infection that makes forceful breathing difficult. Stop and report dizziness, chest discomfort, severe coughing, or worsening breathlessness during the test. Seek urgent help for severe breathing difficulty, blue lips, confusion, or collapse.

Ask what each measurement represents, whether your effort was adequate, whether you need repeat testing, and how the result fits your symptoms, examination, and medicines. Ask what changes should prompt an earlier review.