Saturday, November 28, 2009

Applying Frequency & Vibration: The Innovative "Lung Flute"

The Pied Piper of Mucus, by Corey Binns

The following article in Popular Science interested me, partly because Sandy Hawkin's innovative idea came directly as a result of his understanding of sound and vibration.

The plastic tube Sandy Hawkins hands me looks more like a toy horn than a medical device. Blowing into it, he tells me, will do wonders for my chest cold. I glance at the dozen or so people enjoying their mid-afternoon Starbucks and give it a few skeptical puffs.

The idea for the horn came one night in 1985. Hawkins, an acoustics engineer, and his colleagues began brainstorming how they could use sound to mess with various bodily functions. They joked about what frequency a toilet would need to vibrate at to force an uncontrollable bowel movement and, slightly more seriously, a way to dislodge goo in sick people’s lungs. Months later, Hawkins was reminded of that discussion when he learned that chronic obstructive pulmonary disease (COPD), a group of lung diseases that includes emphysema and chronic bronchitis, makes breathing tough for 10 million people, and causes 127,000 deaths in the U.S. every year. “It’s the number-four cause of death in the U.S.,” he says. “I thought, ‘Yeah, I should do something about this.’ ”

In healthy lungs, hairlike cilia on the bronchial walls wiggle in unison to ferry mucus up the trachea and into the mouth, where it can be swallowed or spit out. Patients with COPD, however, secrete more mucus than the cilia can remove, and thick gobs of the stuff build up in the lungs, making them a breeding ground for bacteria that can lead to pneumonia. Vigorous coughing can help dislodge it, but many sufferers require drugs to open their airways; some need help from oxygen tanks. Annually, the combined cost of treatment totals upward of $27 billion.

Hawkins began building an electronic sound machine that would produce waves of 16 hertz—the same frequency at which the cilia move—to help break up the mucus. Generating a hum of such a low frequency normally requires van-size subwoofers, and so he spent 15 years honing and shrinking the speakers. Then one day as he was testing a mouthpiece filter for his machine, he noticed that blowing through it sent a slight vibration into his chest. Within five seconds, he sketched out the Lung Flute to amplify the effect. Blowing into the tube flaps a reed-thin sheet of plastic, which vibrates the chest and shakes the mucus until it’s thin and mobile enough for the cilia to usher it up your throat. “I felt so stupid because the answer was so simple,” Hawkins says.

Today, doctors in Japan use the $40 Lung Flute as a tool to collect sputum from patients suspected of carrying tuberculosis, and in Europe and Canada it’s used to help test phlegm for lung cancer. Clinical trials in the U.S. have shown that it is at least as effective as current COPD treatments. At press time, Hawkins expected the device to receive FDA approval any day, and says the reusable device could also provide home relief for patients with cystic fibrosis, influenza and asthma.

As Hawkins tells me all this, I notice that my cough has become more productive, and although he deserves my congratulations, I can’t stick around to chat. Instead, I head outside and march to a storm drain to resolve the situation.