Noninvasive Methemoglobin Monitoring Technology

Funded by NIH, Grant No.: 1R43HL087584-01A1
Patent No.: Pending

The Need

Methemoglobinemia is a disorder often found in individuals exposed via environmental or work-related chemical exposures and from pharmaceutical agents such as local anesthetics, acetaminophen, and drugs containing nitrates and/or nitrites . Children, especially under four months, are particularly susceptible to methemoglobinemia and it is estimated about 8% of newborns in neonatal intensive care units (NICU) suffer from methemoglobinemia. The disorder is characterized by a higher than normal ratio of methemoglobin to hemoglobin in the blood. The molecule methemoglobin is a form of hemoglobin with the ferric state of iron (Fe3+) in the heme group rather than the normal ferrous state of iron (Fe2+). Methemoglobin is unable to reversibly bind oxygen so its presence in the body, while normal in small levels, is unnecessary because it cannot distribute oxygen to cells. The reason for the hemoglobin imbalance is due to an enzyme deficiency that reduces the ferric (3+) heme to the ferrous (2+) heme. In most cases the methemoglobin to hemoglobin ratio will diminish with treatment of Methylene Blue which restores the methemoglobin to the oxygen carrying hemoglobin.

The Idea

CW Optics proposes a reliable, noninvasive, and cost-effective methemoglobin sensor that will provide realtime methemoglobin fraction readings to clinicians based on the state of the patients' hemodynamic conditions to allow for the application of timely interventions. The current technology for measuring methemoglobin known as co-oximetry is invasive, requires hemolyzed blood samples, and does not provide realtime results. This new optically analyzed technology will be especially positive in neonatal care where it can be difficult to assess neonates intravenously.

The Science

Technology developed for this device will consist of a sensor that uses four light-emitting-diodes (LEDs) as light sources and a detector. The implementation of an innovative data analysis model that is based on phenomenological algorithms rather than empirical algorithms that are employed in commercial co-oximeters will provide for more accurate determination of methemoglobin levels.

The Bottom Line

Early detection of methemoglobinemia will result in better diagnosis with less time and money spent by the patient and the healthcare facility. The innovations made technologically and analytically could direct advancements in other aspects of the medical researching field leading to better and more efficient healthcare.