Spiral Electrode Sensor for Intrapartum Fetal Oximetry

DESCRIPTION (provided by applicant): Fetal heart rate monitoring is intended to detect signs of fetal distress due to oxygen starvation of the fetus. Unfortunately these methods of fetal monitoring are subject to a high incidence of false positives, resulting in more than 200,000 unnecessary cesarean section deliveries in the U.S. each year with an associated cost of over $1 billion per year. Clinicians have long recognized that direct measurement of fetal oxygen status would provide a more definitive indication of fetal well being. Other methods of fetal surveillance only provide secondary indications of fetal hypoxia. Direct and continuous measurement of fetal oxygen saturation during labor requires the use of pulse oximetry, the continuous, noninvasive measurement of oxygen saturation in arterial blood. Intrapartum fetal pulse oximetry has only recently been made available as a commercial product, but with severely limited success. In particular, the "Indications for Use" of the only available commercial product state that it "is intended as an adjunct to fetal heart rate monitoring in fetuses with a non-reassuring fetal heart rate pattern. It must be used in conjunction with clinical signs and symptoms." Further, the American Cotlege of Obstetricians and Gynecologists (ACOG) has recently issued a Committee Opinion stating that it cannot endorse the adoption of this new technology in clinical practice and is recommending further clinical trials. Kestrel Labs, Inc. proposes to develop a fetal pulse oximetry sensor for continuous measurement of fetal oxygen status and heart rate from a single, easily-accessible monitoring site located on the fetal scalp. Unlike current sensor technology, which uses a "blind" insertion method, has no means for securing the sensor to the fetus, and requires repositioning nearly 4 times an hour, the Kestrel Labs fetal oximetry sensor will be easy to insert, securely attach to the fetal scalp, and will require no maintenance once placed. This SBIR Phase I effort focuses on determining the optimum optomechanical configuration of this new fetal oximetry sensor.