US-12616398-B2 - Systems and methods for monitoring an analyte or parameter for a patient

Abstract

A sensor system includes a probe, and a photon source configured to direct photons at the probe. The probe can emit light in response to receiving photons. The sensor system can include a photodetector configured to detect the light emitted from the probe, and a configured to cause the photon source to emit photons according to a first time-varying intensity profile having a first frequency. The controller can be configured to receive optical data from the photodetector based on the interaction between the light emitted from the probe and the photodetector. The optical data can include a second time-varying intensity profile having a second frequency. The second frequency can be substantially the same as the first frequency. The controller can be configured to determine a difference in phase between the first time-varying intensity profile and the second time-varying intensity profile, and generate a report based on the difference in phase.

Inventors

• Juan Pedro Cascales Sandoval
• Conor L. Evans

Assignees

• THE GENERAL HOSPITAL CORPORATION

Dates

Publication Date

20260505

Application Date

20210901

Claims (20)

1. 1 . A sensor system for monitoring a patient, the sensor system comprising: a first probe sensitive to an analyte and comprising a plurality of operational ranges for monitoring a patient, the plurality of operational ranges having at least a first operational range and a second operational range; a photon source configured to direct photons to the first probe, wherein the first probe is configured to receive the directed photons and to emit light in response to the received photons; a photodetector configured to detect the emitted light; and a controller in communication with the photon source and the photodetector, and configured to: control the photon source to such that, in operation, the photon source directs the directed photons to the first probe according to a first time-varying profile and the first probe is excited relative to the first operational range and relative to the second operational range and emits the emitted light in response to the received photons; receive optical data from the photodetector based on an interaction between the emitted light and the photodetector with the first probe operating in the first operational range and in the second operational range, wherein the optical data includes a second time-varying profile; determine a difference between the first time-varying profile and the second time-varying profile; and based on the determined difference between the first time-varying profile and the second time-varying profile, determine a parameter associated with the analyte.
2. 2 . The sensor system of claim 1 , wherein the first probe includes respective phosphors or phosphorescent regions that each provide one of the first operational range and the second operational range.
3. 3 . The sensor system of claim 1 , wherein the controller is further configured to select a first characteristic of the first time-varying profile to excite the first probe relative to the first operational range and select a second characteristic of the first time-varying profile to excite the first probe relative to the second operational range.
4. 4 . The sensor system of claim 1 , wherein the controller is further configured to control the photon source such that in operation the photon source directs the directed photons to the first probe according to the first time-varying profile to simultaneously excite the probe relative the first operational range and the second operational range.
5. 5 . The sensor system of claim 1 , wherein the first time-varying profile comprises a first signal for exciting the first probe relative to the first operational range and a second signal for exciting the first probe relative to the second operational range.
6. 6 . The sensor system of claim 1 , wherein the first operational range has a first sensitivity or a first response curve relative the analyte and the second operational range has a second sensitivity and or second response curve relative to the analyte.
7. 7 . The sensor system of claim 1 , wherein an operational range of the sensor system is defined by a sum of the first operational range and the second operational range.
8. 8 . The sensor system of claim 1 , wherein the controller is configured to form the first time-varying profile by combining a plurality of sine waves, a plurality of square waves, a plurality of triangle waves, a plurality of sawtooth waves, a plurality of impulse functions, or a plurality of non-periodic waves.
9. 9 . The sensor system of claim 1 , wherein the second time-varying profile comprises a time-varying amplitude wave comprising a phase and an amplitude and the analyte includes a partial pressure and the controller is further configured to determine the phase and the amplitude and determine the partial pressure based on a difference in the phase and the amplitude.
10. 10 . The sensor system of claim 1 , wherein the first time-varying profile includes a plurality of frequencies including at least a first frequency for the first operational range and a second frequency for the second operational range.
11. 11 . The sensor system of claim 1 , further comprising a second probe having a third operational range and wherein the controller is further configured to create the first time-varying profile from a plurality of signals having at least a first signal and a second signal, the first signal having a first characteristic and the second signal having a second characteristic wherein the first characteristic is distinct from the second characteristic and the first characteristic target the first probe and second characteristic target the second probe.
12. 12 . The sensor system of claim 1 , wherein the difference is a phase difference.
13. 13 . The sensor system of claim 1 , wherein the analyte includes oxygen or the parameter includes partial pressure or both.
14. 14 . The sensor system of claim 1 , wherein the first probe is capable of physically contacting a patient tissue or capable of fluidly contacting a zone disposed over a portion of the patient tissue in contact with, gas communication with, or fluid communication with the zone on the patient that is separated from the ambient environment by a membrane which is impermeable or semi-permeable to the analyte.
15. 15 . The sensor system of claim 1 , wherein the first probe includes: a semipermeable layer enabling the analyte to selectively diffuse therethrough; and a light absorbing layer configured to absorb light directed therethrough, a light scattering layer configured to scatter light directed thereto or a light reflective layer configured to reflect light directed therethrough, and wherein the first probe is positioned between the semipermeable layer and the light absorbing layer or between the semipermeable layer and the light scattering layer or between the semipermeable layer and the light reflective layer.
16. 16 . The sensor system of claim 1 , further comprising: a first optical filter optically coupled to the photon source and configured to filter the photons emitted from the photon source that pass through the first optical filter; and a second optical filter optically coupled to the photodetector and configured to filter light that passes through the second optical filter to the photodetector.
17. 17 . The sensor system of claim 1 , wherein the parameter includes a partial pressure of the analyte and wherein, together, the first operational range and a second operational range extends over an overall range between substantially 0 mmHg and 160 mmHg.
18. 18 . The sensor system of claim 1 , wherein the first time-varying profile includes a waveform including a frequency and the second time varying profile includes characteristics and the controller is further configured to adjust the frequency based on the characteristics.
19. 19 . The sensor system of claim 1 , wherein the first time-varying profile includes a sine wave of programmable frequency, a sum of sine waves of programmable frequency, and a square wave of programmable frequency, and the second time-varying profile includes characteristics and the controller is further configured to select the sine wave of programmable frequency, the sum of sine waves of programmable frequency, or the square wave of programmable frequency for the first time-varying profile based on the characteristics.
20. 20 . The sensor system of claim 1 , wherein the first probe includes a first phosphor having the first operational range and a second phosphor different from the first phosphor and having the second operational range, wherein the first phosphor is sensitive to a first partial pressure range and defining the first operational range and the second phosphor is sensitive to a second partial pressure range different from the first partial pressure range and defining the first operational range and the second operational range.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS This application represents the national stage entry of PCT International Application No. PCT/US2021/048747 filed Sep. 1, 2021, which claims priority to U.S. Patent Application No. 63/073,426 filed Sep. 1, 2020, and entitled, “System and Methods for Multi-Dye Frequency Fluorimetry and Phosphorimetry,” which are hereby incorporated by reference in their entirety. STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH This invention was made with government support under FA9550-17-1-0277 awarded by the U.S. Department of Defense's Air Force Office of Scientific Research, and in particular, the Military Medical Photonics Program of the U.S. Department of Defense. This invention was also made with government support under HU0001-17-2-009 awarded by the Military Medicine Transforming Technology Collaborative's Henry M. Jackson Foundation. The government has certain rights in the invention. BACKGROUND Wearable devices have found widespread applications in recent years as both medical devices as well as consumer electronics for sports and health tracking. For example, pulse oximetry is currently used to measure oxygen saturation of hemoglobin in the blood, which can be indicative of systemic oxygen levels. However, these devices lack the ability to directly measure oxygen in tissues (e.g., transcutaneous oxygen monitoring), and thus these devices are not particularly helpful in predicting wound healing, determining an amputation level (e.g., an optimal point to amputate a limb), monitoring hyperbaric oxygen therapy, determining a severity of ischemia, etc. Thus, it would be desirable to have improved portable/wearable systems and methods for oxygen sensing. SUMMARY OF THE DISCLOSURE Some embodiments of the disclosure provide sensor systems or methods for monitoring a patient. The systems or methods can utilize probes for monitoring parameters, such as an analyte. The probe can be configured to have more than one operational range or to monitor more than one analyte or to determine multiple parameters associated with the analyte, or the like. A controller can create, selected, or determine a time-varying profile that can excite the probe relative to the more than one operational range, more than one analyte, or multiple parameters, or the like. Additionally or alternatively, the controller can adjust the time-varying profile to switch between the more than one operational range, more than one analyte, or multiple parameters, or the like. In accordance with one aspect of the disclosure, a sensor system is provided for monitoring a patient. The system includes a probe sensitive to at least one analyte and having at least a first operational range and a second operational range for monitoring a patient, a photon source configured to direct photons at the probe, the probe emitting light in response to receiving photons from the photon source, and a photodetector configured to detect the light emitted from the probe. The system also includes a controller in communication with the photon source and the photodetector. The controller is configured to cause the photon source to direct photons at the probe according to a first time-varying profile to excite the probe relative to the first operational range and the second operational range to emit the light in response to receiving the photons and receive optical data from the photodetector based on the interaction between the light emitted from the probe while operating in the first operational range and the second operational range and the photodetector, wherein the optical data includes a second time-varying profile. The controller is further configured to determine a difference between the first time-varying profile and the second time-varying profile and determine a parameter associated with the analyte based on the difference between the first time-varying profile and the second time-varying profile. In accordance with another aspect of the disclosure, a sensor system is provided that includes a probe, a photon source, a photodetector, and a controller in communication with the photon source and the photodetector. The controller is configured to generate a first time-varying profile including at least two first sub-signals configured to excite the probe relative to both of the at least two first sub-signals and cause the photon source to direct photons at the probe according to the first time-varying profile and excite the probe to emit light in response to receiving the photons. The controller is also configured to receive optical data from the photodetector based on the interaction between the light emitted from the probe and the photodetector, determine a second time-varying profile from the optical data and extract at least two second sub-signals, and determine a condition of a parameter by comparing the at least two first sub-signals to the at least two second sub-signals. In accordance with yet another aspect of the disclosure, a