Pulse oximeter and sensor optimized for low saturation

Abstract

Embodiments of the present invention relate to a system and method for facilitating detection of a physiological characteristic of a patient. Specifically, embodiments of the present invention relate to a sensor comprising a light emitter configured to emit light, the light being optimized to reduce sensitivity of blood oxygen saturation measurements to perturbation induced artifacts for saturations less than 80 percent, wherein the light includes only spectrums in a red range and infrared range including a range of 700 to 790 nanometers, and a detector configured to detect the light.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS [0001] This application is a continuation of U.S. application Ser. No. 10 / 698,962, filed Oct. 30, 2003, which is a continuation of U.S. application Ser. No. 09 / 882,371, filed Jun. 14, 2001, now U.S. Pat. No. 6,662,033, which is a continuation of U.S. application Ser. No. 09 / 003,413, filed Jan. 6, 1998, now U.S. Pat. No. 6,272,363, which is a continuation of U.S. application Ser. No. 08 / 413,578, filed Mar. 30, 1995, now U.S. Pat. No. 5,782,237, which is a continuation-in-part of U.S. application Ser. No. 08 / 221,911, filed Apr. 1, 1994, now U.S. Pat. No. 5,421,329, the disclosures of which are incorporated herein by reference.BACKGROUND OF THE INVENTION [0002] Pulse oximetry is used to continuously monitor the arterial blood oxygen saturation of adults, pediatrics and neonates in the operating room, recovery room, intensive care units, and increasingly on the general floor. A need exists for pulse oximetry in the delivery room for monitoring th...

AI Technical Summary

Benefits of technology

"The invention is a pulse oximeter sensor and system that provides more accurate estimates of arterial oxygen saturation at low oxygen saturations, such as in the range of 15-65%. The sensor and system use optimized wavelength spectrums for the first and second light sources to improve the accuracy of saturation estimates at low saturation values. This is particularly useful for fetal oximetry and cardiac patients with shunting of blood. The sensor and system also improve the immunity to perturbation-induced artifacts, which can be caused by variations in tissue composition, hemoglobin concentration, and force applied between the sensor and tissue. The fetal sensor is optimized for the fetal oxygen saturation range and can be inserted through the vagina. Overall, the invention provides a more reliable and accurate method for monitoring arterial oxygen saturation in low-saturation patients."

Problems solved by technology

In this situation, a high degree of accuracy in the estimate of saturation is not clinically relevant, as much as is the trend over time.

Unfortunately, pulse oximeters which use LED wavelengths paired from the 660 nm band and 900 nm bands all show diminished accuracy at low oxygen saturations.

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