In order to keep the electronics from overheating, most medical electrical equipment use fans that quickly break and vent holes that quickly clog with dust and bugs. These systems meet with FDA approval because they are assuming a U.S. context. Firefly uses a unique fully-sealed design with no moving parts to keep cool and use less energy in hot climates.
A More Robust Electrical System
Many hospitals in low resource settings have power, but it varies up and down during the course of the day, blowing fuses on typical FDA-approved medical equipment. Firefly uses an external power supply so it can continue functioning during wide power fluctuations.
When people ask me whether we are pursuing FDA approval for Firefly, the subtext is whether we are building a safe device, and how we are balancing affordability, time until product launch, and safety for those we serve. My answer usually surprises them: Firefly has been received CE Mark approval, and DtM's partners are also considering FDA approval. However, CE Mark certification and FDA approval don't guarantee safe medical devices for low resource contexts.
Don't be fooled by the phototherapy lamps shining from above; the four nonworking incubators that sit along the walls are used only as hard to clean beds for the well-baby room at a national hospital in Vietnam.
For example, take the bank of broken, high-tech newborn incubators I saw while visiting National OBGYN Hospital, Vietnam. Our extended Firefly team was preparing to treat the first patient in the nine-room Neonatal Intensive Care Unit (NICU). The Firefly room was also used to observed all newborns shortly after birth and to treat the newborns with minor health issues. I noticed many newborns in the room lying inside incubators, traditionally used to provide enclosed, warm environments for critical or intensive care and at odds with the low-intensity care needed for the room's newborns. I asked a nurse why some babies were in incubators and others in open beds. She said that they were broken incubators used simply to provide additional bed and storage space in this room. Some incubators had blown fuses due to power spikes, while others had undiagnosed failures that rendered them useless as anything but spare bedding. Many of these burnt-out devices passed FDA approval and so should therefore technically be considered effective, but there are so many ways a device can fail in a low resource setting. These incubators had become no more than fancy and cumbersome beds.
To design Firefly, we began our detailed engineering design process by pouring over the phototherapy standards used in the FDA approval and CE Mark certification processes. These standards are helpful in that they lay out how bright and uniform the light must be in order to provide clinically effective phototherapy. However, we knew early in the design process that just meeting the FDA and CE Mark standards would not yield a device appropriate for low resource settings. DtM's partnership with East Meets West Foundation and Vietnamese manufacturer MTTS was essential to go above and beyond.
Together, East Meets West Foundation (an affiliate of Thrive Networks) and MTTS have over a decade of experience designing and manufacturing successful newborn health technologies for the poor. In close partnership with hundreds of hospitals in Vietnam, they discovered early on that Western devices fail due to poor training as well as environmental factors including heat, dust, and irregular electrical power. Our manufacturing and implementation partners are continually learning from hospitals, designing and releasing equipment, visiting to learn from any failures, fixing the equipment, and then redesigning the next generation of equipment to even better meet the challenges. Every piece of equipment they build also goes through a basic functionality test before it leaves MTTS. These tests have been custom designed to predict whether equipment will endure in the low resource environment. MTTS and DtM collaborated to recreate this same process for Firefly.
Firefly manufacturer MTTS submits a series of new Firefly devices to the "burn-in test" at their offices in Vietnam. Photo courtesy Michael O'Brien of MTTS.
In order to design a device for success in low resource environments, we took two important steps. First, we poured over the phototherapy standards that FDA and CE Mark use to validate a medical device for use in high resource hospitals with climate control, filtered air, and smooth floors. After that, DtM used our human-centered design techniques to interview MTTS staff in-depth about their experiences in these environments. We invited MTTS to tell us stories of equipment failures and successes, encouraged them to dig up old photos to jog the memory, brought MTTS staff with us on hospital visits, and created a steady line of communication through a series of regular Skype calls to pass on new stories. Building on the best practices for phototherapy design in the first world, our learnings from conversations with MTTS staff, and direct observations at hospitals throughout Southeast Asia, DtM created a unique design that prevents bugs, dust, and liquids from entering and enables Firefly to keep operating during broad power fluctuations.
The vent for the Natus NeoBlue LED Overhead Phototherapy, one of the most popular phototherapy devices used in the United States. An internal fan helps move air through this vent to cool the electronics.
1. Keeping Cool while preventing bugs, dust, and liquids from entering.
Typically, devices with electronics have holes. You may never have noticed, but if you look at your computer, most will have a series of perforations. Most devices with electronics also make a purring sound. For many electronic devices, both of these features are due to the need to keep the electronics cool. The purring sound is usually a fan, and the holes enable it to blow hot air out and bring cool air in. These features keep the device from becoming dangerously hot to touch, and also to ensure the electronic components can perform optimally.
Design that Matters used rubber o-rings to create a seal around the metal tubes where they enter the base of the device. This helps keep bugs and dust out of the device.
In a U.S. hospital, electro-mechanical medical devices share these same cooling solutions. However, when these devices are taken to low resource contexts, they run into trouble. The interior fills with dust and insects. The fans are often the first thing to break, causing the electronics to overheat and burnout in the warm environment. A DtM friend in India quipped, "You haven't really tested a piece of electronic technology for distribution in Asia until you've trained a cockroach to climb in and pee on every single little component on the inside."
Left: The inside of the Firefly top light, showing the metal housing that helps wick heat out the top. Right: The cooling fins are mounted on a slanted surface on the bottom of Firefly to pull heat down from the electronics and then air moves the heat off the rear.
Instead of fans, another way to keep electronics cool is by exposing a large surface area to the air. You may have noticed cooling fins on other home electronics like your refrigerator. Metal cooling fins increase the amount of area exposed to the air on the bottom of Firefly and increase conduction compared to a flat, plastic outer surface. In order to completely seal Firefly, DtM designed a novel passive cooling system for the top and the bottom. The top light was easier to design because heat rises: we manufacture the top light from an aluminum extrusion that has sufficient surface area on top to enable heat from the top lights to rise upward and away from the device. The bottom light was more difficult because any rising heat could directly contribute to overheating the newborn in the bassinet. For this issue, we designed a tilted bottom surface and installed cooling fins. Because hot air rises, air from the lowest part of the device rises up along the fins, cooling the base electronics and enabling the majority of the heat to rise off the rear.
The laptop-like power supply from our Firefly clinical evaluation model prevents Firefly from burning out during a power surge, and relocates the hot power supply outside of the device and away from the baby.
The answer? Laptops! During field research in hospitals in eight countries throughout Southeast Asia, we were always able to use our laptops! Most laptop power cords include a "brick" - that is the power supply. Reading the numbers on the brick, most of these power supplies accommodate a range of voltages for input. In the end, we were able to find an existing off-the-shelf power supply integrated with a power cable that is CE Mark certified for medical use, can accommodate 100-240 Volts AC, and keeps the hot power supply outside of our sealed device and away from the baby, just like a laptop power cord!
The evidence was laid out in front of us; FDA approval and CE Mark certification focus on hospitals with big resources. To design Firefly to work well in low resource contexts, DtM leveraged field experience to go beyond known phototherapy standards in order to deliver a device that meets a higher standard of care. Firefly received CE Mark certification, and our partner MTTS is also considering FDA approval to enable the device to reach western markets, creating new revenue streams and beneficial product pricing structures that will enable us to reach many more in the developing world. We are proud to partner with East Meets West Foundation and manufacturer MTTS and their joint vision of designing devices that really work in hospitals with few resources. Our partners will continue to monitor Firefly in the field, ready in case anything needs to be fixed, constantly learning what improvements we might make for the next generation.
This "Design Experience that Matters" series is provided courtesy of Timothy Prestero and the team at Design that Matters (DtM). As a nonprofit, DtM collaborates with leading social entrepreneurs and hundreds of volunteers to design new medical technologies for the poor in developing countries. DtM's Firefly infant phototherapy device is treating thousands of newborns in 21 counties from Afghanistan to Zimbabwe. In 2012, DtM was named the winner of the National Design Award.
Elizabeth Johansen is Senior Advisor to Design that Matters (DtM), Principal of Spark Health Design Consultancy, and Adjunct Faculty at Olin College of Engineering's Affordable Design & Entrepreneurship Program. Elizabeth uses human-centered design to develop world-class technologies that lead to better health outcomes. She is also a sought after speaker and facilitator who has taught design for social impact to hundreds of organizations, from the smallest social enterprise to the largest bank in the world. Notable product launches include Eli Lilly's Kwikpen insulin injector (during former days at IDEO); Jana Care's improved Aina A1c rapid diagnostic test app for diabetics at home; and DtM's Firefly phototherapy device currently treating newborns with jaundice in over twenty developing countries. Firefly has earned ten design awards including the Edison Gold, IDSA IDEA Silver, and Green Good Design.