We've all worn one in the hospital or doctor’s office: a small plastic device that clips onto a fingertip to monitor oxygen levels in the blood. Currently, these devices—called pulse oximeters—require a bulky box to gather and report data, and they cost enough that only hospitals and clinics can readily afford them.

Now, a company called LionsGate Technologies Inc. (LGTmedical) is gearing up to produce a newer, cheaper device called the Phone Oximeter. It can be attached to a smartphone and costs only $40. Once the Phone Oximeter enters mass production, the price should drop even lower.

The technology could have a huge impact in the developing world, where many clinics, community workers, and even hospitals don’t have access to pulse oximetry. A pulse oximeter is especially important in emergency rooms and is also used to monitor heart and respiratory conditions.

Unlike other mobile-enabled pulse oximeters, the Phone Oximeter is uses the smartphone’s processor to do all the necessary computing. This means that the device itself need only consist of two LEDs and a small sensor.

“What this really does is it looks at the color of the blood going through a finger,” explained Dr. Mark Ansermino, an associate professor at the University of British Columbia (UBC), in an interview with Healthline. “If there’s a slight degree of blue in that blood then it means it doesn’t have enough oxygen in it. This is much more sensitive than we can actually see with the naked eye. ”

Ansermino, along with colleagues Guy Dumont and Peter von Dadelszen at UBC, developed the Phone Oximeter before transferring it to LGTmedical for manufacturing.

“The other really important innovation is that we’ve used the audio jack of the phone as the universal connector of any mobile device to be able to do this monitoring,” said Ansermino. “It uses the same channels that would produce sound and record sound from the microphone to light up the lights and record the amount of light that actually goes through the finger.”

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Low Cost, Widespread Access

LGTmedical is partnering with The Sensor Project, which is raising money to bring Phone Oximeters to about 80,000 women in India, Pakistan, Nigeria, and Mozambique. They’re part of a study funded by the Bill and Melinda Gates Foundation on preeclampsia, a condition involving high blood pressure that affects about 10 percent of pregnant women.

Most women with preeclampsia have no complications and deliver a healthy baby. However, for some, complications can include premature birth, bleeding, stroke, seizures, or even death. Preeclampsia is the seconding leading cause of maternal death and kills more than76,000 women and 500,000 infants every year worldwide.

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“We’ve spent a number of years studying the predictors and we’ve found [blood oxygen level] to be a very powerful predictor of which women will actually develop complications,” said Ansermino. The Phone Oximeter can successfully predict preeclampsia complications from blood oxygen levels alone with about 80 percent accuracy.

Although preeclampsia can be detected by measuring high blood pressure, the elevated pressure is only a symptom of the core condition, which is widespread inflammation of the entire body. This inflammation particularly affects the blood vessels, but it can also affect the lungs, causing them to swell and reducing the amount of oxygen that they can absorb into the bloodstream.

“The amount of oxygen that’s going through your blood is a very important clinical sign for us as physicians in many diseases,” Ansermino said. “If you’ve got any disease that affects your lungs, the level of oxygen in your blood goes down even before you get into the critical stages of that disease. That’s the reason why now, in hospital, almost every patient has one of these wrapped around their finger.”

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Although The Sensor Project’s study will focus on preeclampsia, the Phone Oximeter has applications for other diseases. “Every year, more than two million kids die from infectious diseases before they reach the age of five," said Ansermino. "Pneumonia, malaria, diarrhea: all of these diseases affect the lungs. All of these diseases go through a general deterioration that affects the entire body, including the lungs. That’s where we think this technology can be used to detect early on when these children are likely to develop complications.”

The Phone Oximeter is awaiting FDA approval, which Ansermino expects to receive later this year. For now, it will go on sale next month for non-medical markets, to be used by athletes, pilots, and others who want a cheap and portable way to measure their blood oxygen levels.

Public-Private Funding Makes Innovation Possible

LGTmedical received funding from a group of angel investors, as well as a matching grant from Grand Challenges Canada, an organization funded by the Canadian government's Department of Foreign Affairs, Trade and Development.

“Canada’s been a global leader in focusing on maternal and children’s health,” said Dr. Peter Singer, CEO of Grand Challenges Canada, in an interview with Healthline. “What you’ve got here is combining public and private finance to achieve important humanitarian goals. We use the public money to capitalize private investment. This is Silicon Valley meets international development.”

The Phone Oximeter is the first investment made from a new $10 million grant that Grand Challenges Canada received from the Canadian government. “We support bold ideas with big impacts in global health,” Singer said. “This is an incredibly cool innovation that we’ve supported since the proof of concept stage. That’s why we selected the company: they had broad reach and a big potential for impact.”

Ansermino is grateful for the broad support. “The most innovative thing about this is the business model,” he said. “It’s really unusual for a business to try to make something as cheap as possible. It’s been a huge struggle to try and convince people that the impact of what we do as a commercial enterprise is more important than the profit that we make. This is true social entrepreneurship.”

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