Spirometry

Examination method with which the lung function can be checked.

Spirometry readings vary depending on gender, height, and age. Trained athletes often have a larger lung volume than the untrained.

The most important parameters of spirometry are:

• Peak Flow (PEF) see below. Peak Flow Meter
• Respiratory Volume: equal to the amount of air inhaled and exhaled during each normal breath.
• Inspiratory Reserve Volume (IRV), describes the volume of additional air that can be inhaled or exhaled after normal inspiration with maximum effort.
• Vital capacity (VC) and forced vital capacity (FVC): The sum of normal respiratory volume and reserve volume.
• One-second-per-second capacity (FEV1): Volume of air that can be forcefully exhaled within one second after maximal inspiration. An FEV1 of < 80% and a Tiffeneau index (FEV1/VC) of < 70% are indicative of airway obstruction.
• If airway obstruction is suspected, a bronchospasmolysis test should be performed (see chronic obstructive bronchitis).
• Bronchospasmolysis test: Spirometric test performed before and after application of a short-acting beta-2-mimetic (alternatively with a high-dose inhalable glucocorticoid). A positive brochospasmolysis test is present if the following criteria are met in the 2nd spirometry: increase in one-second capacity (FEV1) by >200ml or 15% 10-15 min after inhalation of the short-acting beta-2 mimetic.
• If there is complete normalization of the Tiffeneau index after inhalation of the beta-2 mimetic, bronchial asthma is most likely present. An absent or inadequate response to the beta-2-mimetic may be indicative of COPD.
• Flow-volume curve: The measured values can be plotted as a graph. In the flow-volume curve, the respiratory flow (volume/time) is plotted against the respiratory volume.

Clarification of chronic cough, shortness of breath, breathing sounds

for mainly diseases of the lungs, chest, heart

in particular in disorders of the respiratory centre in the brain and the respiratory muscles

in long-term smokers, to detect restrictions in lung function

on health care (non-routine)

before planned operations - to assess lung function.

During spirometry, the patient breathes through a mouthpiece with the nose closed with a clamp. The spirometer measures the amount of air breathed and the speed of the airflow. This allows conclusions to be drawn about lung volume and lung function.

In ergo-spirometry, lung function is measured during a defined physical exercise. Ergo-Spirometry is mainly used for performance diagnostics in athletes, but also for the diagnosis of cardiovascular and pulmonary diseases.

1. Koegelenberg CF et al.(2012) Guideline for office spirometry in adults, S Afr Med J 103:52-62.
2. Laszlo G (2006) Standardisation of lung function testing: helpful guidance from the ATS/ERS Task Force. Chest 61:744-746.
3. Miller MR et al (2005) ATS/ERS Task Force... Standardisation of spirometry. Eur Respir J 26:319-338.
4. Seyedmehdi SM et al,(2013) Quality of spirometry tests and pulmonary function changes among industrial company workers in Iran: a two-year before-and-after study following an intensive training intervention. Prim Care Respir J 22:86-91.
5. Upton MN et al (2000) Improving the quality of spirometry in an epidemiological study: The Renfrew-Paisley (Midspan) family study. Public Health 114:353-360.