Author
Home > Health > What is the Difference Between Peak Flow and Spirometry?

Guilherme Mazui

•3 minutes to read

What is the Difference Between Peak Flow and Spirometry?

🆚 Go to Comparative Table 🆚

Peak flow and spirometry are both tests used to assess lung function, but they serve different purposes and provide different types of information.

Peak Flow:

  • Measures the maximum speed at which a person can blow air out of their lungs.
  • Provides a general idea of how narrow the airways are.
  • Can show how much the airways are changing over time if measured daily.
  • Not recommended for children under 12 years.
  • Not recommended to confirm whether a person has asthma.
  • Can be used to help monitor lung function and follow an Asthma Action Plan.

Spirometry:

  • Measures the mechanical function of the lungs, chest wall, and respiratory muscles by assessing the total volume of air exhaled from total lung capacity.
  • Confirms the diagnosis of asthma and other lung conditions.
  • Provides more comprehensive information about lung function than peak flow.
  • Recommended for children and adults.

A study comparing peak flow measurements to spirometry found that peak flow measurements were significantly higher than spirometry measurements, suggesting that peak flow may not be as reliable as spirometry for assessing lung function. Peak flow monitoring can be a useful tool for monitoring lung function and following an Asthma Action Plan, but it is not a substitute for spirometry in diagnosing asthma or other lung conditions.

On this page
  • What is the Difference Between Peak Flow and Spirometry?
  • Comparative Table: Peak Flow vs Spirometry

    • Comparative Table: Peak Flow vs Spirometry

    Here is a table comparing the differences between peak flow and spirometry:

    Feature Peak Flow Spirometry
    Purpose Monitors lung function and helps asthma patients decide on medication usage. Measures lung function and diagnoses diseases that affect breathing, such as asthma, chronic bronchitis, chronic obstructive pulmonary disease, pulmonary fibrosis, and emphysema.
    Device Portable, inexpensive, and easy-to-use. Performed by a medical practitioner with a spirometer, a device found in a medical practitioner's office.
    Measurements Measures the maximum (or peak) speed at which a person can blow air out of their lungs. Measures forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), vital capacity (VC), and peak expiratory flow (PEF).
    Test Duration Takes about 2-3 seconds per measurement. Takes about 15 minutes and requires the patient to exhale into the tube as hard as they can for several seconds at least three times.
    Monitoring Recommended as a guide to help patients and health professionals monitor lung function. Used to detect early changes and disease progression, as well as to monitor the effects of medications and exposures.

    Keep in mind that peak flow monitoring is not the same as spirometry and is not recommended for confirming whether a person has asthma.

    Read more:

    Guilherme Mazui

    Guilherme Mazui is graduated in journalism from the Federal University of Minas Gerais (UFMG) and a master's degree in Communication from the University of São Paulo (USP). In addition, he has experience in advertising writing and has worked as a content editor in several companies.