Three-year old Naomi Shaviss landed in the hospital after her wheezing wouldn't go away.
Her father was worried.
Robert Shaviss, Naomi's Father: "Oh, no. Are we about to have another episode? Is this bad?"
Robert says doctors began treating Naomi for asthma last year, but for some toddlers, a diagnosis is more difficult.
"Deep breath, Blow it out!"
With older children, doctors can use a test called Spirometry to measure lung function that's nearly impossible for toddlers.
Daniel Weiner, MD, Pediatric Pulmonologist: "We have to get children to fill their lungs completely up and blast it out very hard and fast. Most little kids can't do that on their own."
That's when doctors may use a special device to help them.
During an infant lung function test, the child is sedated and placed in a special Plexiglas bed wearing a face mask.
An inflatable bag is placed over the baby's chest and a vest over that.
Doctors fill the baby's lungs.
"That's probably gonna be in the next breath."
Then inflate the bag so the vest gives the child a squeeze, helping him forcefully exhale.
This technology is already being used to test for chronic lung diseases like cystic fibrosis. Now some are using it to test kids for asthma who aren't responding to other treatments.
Weiner: "Ten or 15 years ago people would say this is purely a research test and one should never take the risk of sedating a child to measure their lung function. But I think we're finding that there are many reasons where it's important to know their lung function."
"Give me a high five. Good girl!"
Shaviss: "You need to know what's going on because if you don't, asthma can be life-threatening unless it's diagnosed-and kept under control."