Folks with asthma, COPD, cystic fibrosis, and other pulmonary problems may be able to improve their lifestyles and the effectiveness of prescribed therapies by keeping an eye on their blood oxygen saturation. Portable pulse oximeteters that provide continuous oxygen saturation readings are available from a variety of manufacturers, including one that works with an iPhone, but they all rely on a sensor that clips onto a fingertip or ear lobe. That’s because blood in those spots is close to the surface and the sensor can shine two wavelenghts of light through the tissue and measure how it’s attenuated.
This presents a challenge to continuous all-day monitoring of blood oxygen saturation, so Oxitone, a company out of Ashkelon, Israel, claims to have developed a pulse oximeter that can be built into the bottom of a wristwatch to measure O2 saturation and pulse rate at the wrist.
From Oxitone’s technology page:
The secret source of the Oxitone technology is exploiting the synergy of a set of noninvasive optical sensors of a different nature. Oxitone developed a unique optical solution which has never been explored before. Specifically, Oxitone’s photoplethysmography (PPG) sensor is designed such that it detects the same amount of physiological information that conventional fingertip probes provide.
Another side of the Oxitone solution is using a complementary blood flow sensor. This sensor exploits a coherent light scattering technique, or so called “dynamic speckle”, that allows continuous measurements of blood rheological parameters. The system based on a synergy of PPG and blood flow sensors provides information unavailable with other optical systems.
Finally, an intelligence algorithm identifies and process needed information taken from these complementary optical sensors of a different nature to get the complete picture of the patient’s current condition.