although i am not quite sure how it happened, i have become known as a medical device inventor. i am not an engineer or a physician, and though i'm increasingly referred to as a "biohacker" by the media, i have no idea what the term means.
i invented my first device when i was a seven-year-old. growing up on a farm, one of my chores was to shell peas, and, impatient to get back to the fun of being a kid in the country, i invented a machine to shell those peas faster. too fast as it turned out, since the peas shot all over the yard, and all i was left with were the inedible shells. my mom wasn't too happy, but that experience helped me understand that unexpected outcomes were all part of the process. many years later, as a person with cystic fibrosis and desperate for an effective treatment to clear my airways, i developed a device known as the chestmaster high frequency chest wall oscillation (hfcwo) system. during its development, i've been reminded of that lesson time and time again.
|the chestmaster device for treating cystic fibrosis breaks up thick bronchial secretions, enabling them to be removed by coughing. image from dean kalyan photography.|
living with cystic fibrosis
i was two months old when i was diagnosed with cystic fibrosis (cf), a systemic disease causing particular damage to the liver, spleen, digestive system, and lungs. people with the disease must wrestle with their lungs filling up with mucous that is difficult to expectorate and if not cleared out of the respiratory tract, results in extreme difficulty in breathing and severe infections that cause scarring in the lungs. scarring in the lungs leads to decreased respiration capacity, quality of life, and lifespan.
there are a few devices on the market that are designed to move that mucous upward and outward, but i didn't find any of them to be as effective as the chest percussion therapy (cpt) i had received as a child from my mom, or from a physiotherapist as an adult. i live in a rural community, three hours away from the nearest cf clinic, so regular visits were not an option and most cf patients avoid the clinic as much as possible since our risk of cross-infection is extremely high.
inventing the chestmaster device
i needed a device that would simulate the manual pounding on my chest and back and allow me to take deep breaths during treatment so that i could cough and expectorate the mucous. the two hfcwo vests on the market couldn't offer that since they use air bladders, attached to a compressor by hoses, which squeeze the thorax and limit the ability to take deep breaths. vigorous exercise that required deep breathing produced great results for me, so i wanted a device that could facilitate deep breathing and freedom of movement during treatment.
over the course of a year i came up with several ideas for a device that met the above criteria. after i had a design that seemed feasible, i scavenged for spare metal pieces and came upon a sewing machine engine and standard electrical box to use in my prototype. after soldering it all together, i had what looked like a cross between an iron maiden and buzz lightyear apparatus. i slipped the metal contraption over my head, plugged it in and was promptly knocked off my feet by the force.
many tweaks and redesigns later, i had a device that simulated manual cpt amazingly well. it wasn't pretty and i was anchored by a cord to the nearest electrical socket, but it worked. it worked so well that my family and i decided to see what a contract manufacturing firm could do with it to refine it into a device that could help others like me with cf, chronic obstructive pulmonary disease (copd), and neuromuscular disorders. as a representative of the patient population that was going to be using this device, i knew what features would make this device most beneficial.
refinement in contract manufacturing
first and foremost, the chestmaster device needed to vibrate individual sections of the lungs independently to allow for customized therapy options to accommodate lung infections, broken ribs from coughing, and port placement in the upper chest. collaborating with starfish medical (victoria, bc, canada), we accomplished this through the use of individual voice coils, positioned in precise locations on the front and back of the vest, with adjustable frequency and amplitude and the ability to turn off each voice coil, as required. painstaking trial and error for precise placement for maximum efficacy and problematic issues with the voice coil and housing ensued. testing each iteration, i was able to tell the team if it was successful.
a universal fit that would work for both genders comfortably was the next priority. a common complaint with hfcwo vests for women is discomfort around their breasts, and both genders often experience itching and rashes from the treatment. i quickly learned that good industrial design was key to my project's success. i am grateful to have had ryan lee, one of the best industrial design professionals in the industry, on my team. from the voice coil placement to the construction of the vest that would hold them, his expertise was instrumental, and as such, i've asked him for a few words on how we addressed this challenge.
"there was a large challenge in developing a structure that was robust enough to maintain treatment forces against the body, yet supple enough to facilitate the patients breathing while maintaining contact with the treatment area," says lee, who left starfish this month. "iterative, fast, proof of concept prototypes allowed a series of discoveries to facilitate a design direction. knowledge of a wide range of materials, and a cunning combination of key materials created a solution that leveraged their positive influences collectively."
i am very pleased to report that the chestmaster vest fits up to the 95th percentile of users and accommodates breasts, pregnancy, ports, mickey buttons (ports for feeding tubes --a common sight in the abdomens of cf patients), and does not create itching sensations or rashes.
the third criteria was that the device needed to allow for mobility and extended time away from a power outlet to support outdoor activity. typically, people with cf are confined to their homes due to the need for treatment, and avoidance of crowds and public confined spaces in which infections are so easily spread. feeling lonely, cut off from the world, and physically unfit are not conducive to health. it was imperative that the chestmaster device be portable and battery powered so that users could go about their daily activities during treatment. it's estimated that the average person with cf spends the equivalent of four months of full-time work doing treatments every year. imagine what it's like for small children to spend that kind of time in one spot! when your life expectancy is somewhere around 45-years of age, every minute counts.
unlike the other hfcwo devices, the chestmaster didn't use a compressor so that helped facilitate portability, but we still had the issues of power supply and electrical control board to manage. switching to rechargeable lithium batteries rendered the vest cordless, though it took some investigation to figure out just the right configuration to make them last for two to three days without needing to recharge. this enables travel, camping, and sleepovers for those who would otherwise be homebound. similarly, designing the electrical board to be small enough to fit on a belt, along with the battery pack, proved to be a challenge, and is in fact still being refined. i am grateful to mark drlik, our engineer and project manager at starfish medical and, and the rest of the chestmaster development team for their dedication and hard work to make my vision for chestmaster a reality.
|check out the conference track on design, prototype, and usability at md&m west and a session on diy medical devices february 10-13, in anaheim, ca. in addition, starfish medical, which helped develop the chestmaster, will also be exhibiting at the show at booth 572.|
as anyone who has developed a medical device can attest, this is a huge and complex project to undertake. had i known all the challenges, time, and resources it would absorb, i'm not sure i would have done it. having reached this stage though, and being fortunate enough to have received attention from the media, i've received emails and calls from people with cf, copd, and various neuromuscular disorders from all over the world, who, like me, are desperate for a treatment device that is comfortable, effective, and offers them the freedom to live their life. that's made it worth it.
i am 31-years old now and though developing chestmaster has been one of the most worthwhile efforts in my life, the realities imposed on me by my disease make it advisable for me to slow down a bit and spend my time with my family. understanding that i have neither the time nor the expertise to take this to market myself, i've appreciated the mentorship offered to me by successful medtech entrepreneurs like alexei marko at neovasc (richmond, bc, canada). his guidance and collaboration with amanda cooper, our business development associate, has been invaluable and enabled us to attract interest from investors and multi-national medical device companies eager to make it a commercial success. while those discussions are just beginning, i have no doubt that chestmaster will get into the hands of the people that need it and truly change the approach to effective home health care for those who require airway clearance.
marten devlieger is an inventor and the founder of chestmaster (edmonton, ab, canada).