Complex lung function testing aids with the differential diagnosis of the breathless patient and the different multiple causes.
Spirometry is a simple and non-invasive test, which can help with the diagnosis of asthma, when the bronchodilator response is measured. It allows to determine the severity of obstructive and restrictive lung diseases. There are however many clinical scenarios where more complex lung function testing significantly contributes to the diagnostic work up.
Static Lung volume measurements via body plethysmography determine the total volume of air that a person can inhale and exhale, as well as the residual volume of air, aiding the diagnosis of restrictive and interstitial lung diseases.
Static lung volumes assist with the diagnosis and monitoring the progression of interstitial lung diseases, fibrosis, hyperinflation and gas trapping. Body plethysmography can differentiate between an obstructive and a restrictive pathology in clinical scenarios where the spirometry result is of limited value. For example – an obstructive lung disease in an obese patient may produce a spirometry result which suggests a restrictive pathology.
Gas Transfer/Diffusing Capacity Testing measures the lungs’ ability to absorb and diffuse gas into the lungs/blood. Carbon monoxide is used in diffusing capacity testing, and its levels after inhalation and exhalation are assessed to diagnose and monitor conditions. A reduction in the DLCO can help to differentiate COPD from asthma, identify early interstitial lung disease and be an indicator of disease severity in patients with emphysema.
FeNO (fractional rejection of nitric oxide) testing detects nitric oxide in the breath and can indicate any inflammation in the bronchioles. Nitric oxide is a gas produced by cells in the lining of airways, and is an important marker of airway inflammation.
Refer your patient for this test when their spirometry results came back unclear, they are experiencing respiratory condition symptoms, they smoke or second-hand smoke, or they have recently commenced a new treatment plan.
Complex lung function testing allows for a non-invasive work up of a breathless patient beyond the limitations of office spirometry.
All complex lung function testing is available at our North Lakes and Clayfield locations.