Allison Lawlor

For some patients, performing a standard pulmonary (lung) function test to determine how well their lungs are working is difficult. That’s when an innovative forced oscillation technique (FOT) device, developed at Dalhousie University in collaboration with respirologists at the QEII Health Sciences Centre, can help.

The tremoFlo Airwave Oscillometry System is a handheld device that requires a patient to breathe normally into it for a short period of time. Doctors can then measure how difficult it is for the patient to move air into and out of their lungs. For those who might have trouble with standard lung function tests, the tremoFlo device test is much easier to perform. Unlike the standard tests, it doesn’t require patients to take a deep breath to fill their lungs and then forcibly blow out the breath.

“The hope is that with an easier-to-perform test, the tests will be more reliable,” says Dr. Geoff Maksym, director of the School of Biomedical Engineering at Dalhousie University.

The FOT device was developed by Dr. Maksym and his team with $2.4-million in funding from the Atlantic Canada Opportunities Agency and the Natural Sciences and Engineering Research Council of Canada. The device has been used as a research tool by doctors in the QEII’s respirology clinic for more than a decade, and is leading the way to gain a better understanding of how lungs normally function and of small airway lung diseases, such as asthma.

“The plan ultimately is to integrate it into the respirology clinic,” said Dr. Paul Hernandez, chief of the QEII’s division of respirology.

Through a partnership with Dr. Thomas Schuessler, president of Thorasys – the company who manufactures the product - the small portable device has been commercialized and is now approved for use in Canada and Europe. The company is awaiting approval in the United States.

The FOT device, which is hooked up to a computer screen, works by superimposing a gentle multi-frequency airwave onto the patient’s own breathing to measure lung function. Doctors can then get a reliable measurement of lung stiffness and airway resistance.

“The device can feel how hard it is to blow a small puff of air into the patient,” says Dr. Hernandez.

The device also allows doctors to more clearly understand the activity within what Dr. Hernandez calls the lung’s “silent zone” — the small airways.

“This technique allows us to better understand what is going on in the small airways in health and disease,” says Dr. Hernandez.

At the QEII’s respiratory clinic, as many as 50 per cent of patients have some form of airway disease, such as asthma or chronic obstructive pulmonary disease (COPD), a lung disease that includes chronic bronchitis and emphysema. With COPD being the third leading cause of death in Canada and COPD and asthma being the first and third most common cause of admission to hospital among chronic conditions, developing a better understanding of chronic airway diseases is critical to improving overall lung health in Canada, says Dr. Hernandez.

“As clinicians become more aware of the FOT device’s capabilities and benefits, it will be used more in the clinical setting,” he says. “It will add to the tests we already have. No one test can tell the whole picture.”

But in some cases, in which a patient can’t perform other pulmonary function tests, it could be the only test Dr. Hernandez administers.