Breathing tests also called as Lung function tests or Pulmonary function tests are important investigations for children with regular cough, chest congestion or wheezing and asthma. Lung function tests are also required in children with other lung problems like bronchiectasis, cystic fibrosis, interstitial lung diseases etc for diagnosis and monitoring in follow up.

The most commonly performed lung function is a spirometry test. In spirometry the person is required to blow out into the spirometry equipment or spirometer. The procedure is repeated 3-5 times till adequate graphs are obtained. The software then provides values for interpretation. Although spirometry is an excellent investigation, the major drawback of spirometry is that many young children are not able to perform the test properly. This leads to poor quality graphs and values. Hence, spirometry has been used in children over the ages of 5-6 years.

In younger children the diagnosis is made based on signs and symptoms without lung functions being performed. There was a need for a newer test which can be performed easily in young children without the need to blow out. This drawback has been overcome by the availability of Impulse Oscillometry.

How is an Impulse Oscillometry test performed?
During the impulse oscillometry test the child is asked to breathe slowly into a mouthpiece connected to the equipment. Each reading is obtained for a period of 15-20 seconds. Approximately 3-5 impulse oscillomery readings are obtained till graphs and results are uniform. The pneumotachometer (sensor) senses the breathing of the child and calculates the results which are shown on the computer screen.

Can children less than 5-6 years of age perform an Impulse Oscillometry?
Most children more than 3 years of age can perform Impulse Oscillometry properly. Occasionally some kids get cranky and do not cooperate. In such situations Impulse Oscillometry can be performed at the subsequent OPD clinic visit.

How long does it take to conduct an Impulse Oscillometry test?
An Impulse Oscillometry test takes around 5-10 minutes. This is followed by giving medicine through an inhaler and spacer. This is usually a bronchodilator (salbutamol or levo-salbutamol). The impulse oscillometry is repeated after 10-15 min. The values of the pre and post bronchodilator impulse oscillometry results are calculated along with the change after giving bronchodilators.

Facilities for Lung Function Tests at Children’s Chest Clinic
At our facility Children's Chest Clinic we routinely perform lung function tests for children including kids less than 5 years of age. Children’s Chest Clinic is equipped with the Master Screen-Impulse Oscilometry and Spirometry system. The equipment is from Jaeger, Germany and considered to be a state-of-art equipment in the field. Our staff has been well trained to perform lung function tests including spirometry and impulse oscillometry in children.