Wristwatch-style oximeter lets patients measure blood oxygen levels remotely

With all the advances in medical science, doing something as simple as measuring blood oxygen levels is still a major hassle – often requiring patients to be hooked up to devices usually found only in hospitals. And with even simple hospital visits costing someone (usually insurance companies or governments) big money these days, a device that could allow patients to measure blood oxygen accurately at home is likely to be a hit – both with patients and caregivers.

That is exactly what Dr. Leon Eisen of OxiTone Medical in Ashkelon has come up with: An oximeter – a device that measures blood oxygen levels – that patients can wear, with information about their current condition monitored by their bluetooth-connected smartphones. “If a critical blood oxygen threshold that can endanger a patient’s health is recorded, the app that communicates with the device can inform the caregiver of the situation, and appropriate action can be taken,” says Eisen. “With our device, patients can continue going about their normal activities without having to break their routine in order to get their blood oxygen levels measured.”

Blood oxygen level is a useful statistic for anyone concerned about their health, or even for fitness buffs – but it’s a critical statistic for patients with forms of COPD (Chronic obstructive pulmonary disease), who need to ensure that enough air is getting into their lungs. COPD usually accompanies diseases like chronic bronchitis and emphysema, causing the air passages to the lungs to become narrower and limiting the availability of oxygen. Patients feel short of breath and are limited in their ability to do physical activity, and are at risk if they “overdo it.” COPD is actually the third leading cause of death in the U.S.; in 2007, it cost the American economy $42.6 billion in health care costs and lost productivity.

An oximeter (also called a saturometer) is able to indirectly monitor the oxygen saturation of a patient’s blood, avoiding the need to take a blood sample. But most oximeters generally require the patient to be hooked up to a battery of machines and monitors, which analyzes the information – thus requiring the patient to stay put, often in a hospital bed, while the examination takes place. Numerous examinations are needed as well, so the patient has to be repeat the routine several times a day – making it very difficult for patients to engage in normal activities.

There is an alternative to full-scale blood oxygen measurement devices
: A handheld pulse oximeter, which uses infrared light to measure the pulsation of capillaries in the finger. The devices are considered only somewhat accurate – but for most patients, the worst part of pulse oximeter use is the finger pain. Current iterations of the oximeter feature “jaws” that must be clamped onto a fingertip or an earlobe – translucent parts of the body that allow the oximeter (which is based on photodiode technology) to check the level of oxygenated and deoxygenated hemoglobin in the system. Considering that this procedure takes place several times a day for lengthy minutes, patients often complain of finger pain, says Dr. Eisen, even though the clamps are touted as being “pain free.”

Why clamp an oximeter on your finger (or ear lobe!) when you can simply wear one on your wrist, just like a watch, pedometer, or two-way radio (with apologies to Dick Tracy)? That’s exactly the point of the OxiTone Wearable Pulse Oximeter, says Eisen. “The uniqueness of our device is its ability to measure pulse rate and oxygen saturation without hindering wires and painful clips that ‘bite’ the finger,” he says. “The device’s sensors are placed on the wrist and embedded into convenient and familiar wristwatch-like enclosure. It’s much more comfortable and convenient.”

Part of that convenience is the wireless transmission of data to remote servers, without the need for wires, Eisen says. “Because the device is wearable and communicates remotely, patients can wear it at home, when doing leisure activities, or even when they sleep. Our device will provide reliable continuous monitoring and real-time record of a patient’s state of health, through days and nights of changing activity,” Eisen says.  A bluetooth-connected smartphone app records the information and uploads it to caregivers. “Doctors can be informed remotely of their patient’s condition, and in case of emergency give instructions over the phone – or immediately send an ambulance, if the patient is incapacitated.”

The system will also be useful for athletes who want to measure their blood oxygen levels, Eisen adds, with a version of the OxiTone smartphone app recording their blood oxygen level, pulse, and other vital statistics, uploading the information to their personal databases, or sharing it with members of their community.

Eisen is very optimistic about the prospects for his invention (for which he has a prototype, ready for manufacture; the Wearable Pulse Oximeter is a classified consumer device, not a medical device, so Eisen does not need to wait for FDA approval before moving forward with it). And, Oxitone rcently successfully completed proof-of-concept clinical trials at Meir Hospital in Kfar Sava. “We believe that our device will generate a paradigm shift in continuous and prolonged health monitoring by providing a new dimension for high-quality healthcare,” Eisen says. “There is a great demand for a wearable and easy-to-use pulse oximeter  that meets growing consumers’ demands for continuous health monitoring without compromising patients’ daily activity and sleep, and we are ready to fill that demand.”