The research behind consistent and child-appropriate testing for asthma
Asthma is the most common chronic disease in children, affecting nearly 850,000 Canadian children under the age of 14. Thanks to research supported by the Stollery Children’s Hospital Foundation through WCHRI, researchers are exploring ways to more accurately diagnose asthma in children.
One medical test doctors use to diagnose asthma is called a bronchoprovocation test. The test involves a child breathing in a mist or spray from a nebulizer that contains a small amount of an agent called methacholine. The way a child’s breathing responds to the methacholine helps doctors decide whether or not they have asthma.
“The trouble is that different nebulizers vary in terms of how much medication they can transport to the lungs and different laboratories use different nebulizers”, says Andrew Martin, director of the University of Alberta’s Aerosol Research Laboratory of Alberta.
This can make it hard for doctors to interpret test results across labs, but it also puts children at risk of adverse reactions – like fainting and chest pain – if they receive too much methacholine. On top of that, misdiagnoses could be occurring as a result of nebulizers administering either too much or too little methacholine.
Like most medical devices, nebulizers are typically designed for adults, not children.
With funding from a WCHRI Innovation Grant, Martin and his team developed computer models that predict how much medication is deposited into the lungs when using specific nebulizers. Furthermore, Martin’s graduate student, Kineshta Pillay, is focusing on inhaled drug delivery for children and is creating a computational model that incorporates physiological differences related to child development.
Finding ways to know the amount of medication administered and understanding how physiological differences in children can affect the outcome of tests is an important step towards both lowering the rates of misdiagnoses in healthy children and reducing the rates of untreated asthma in those who need care.
