System and method for removing artifacts from waveforms

Information

  • Patent Grant
  • 7725147
  • Patent Number
    7,725,147
  • Date Filed
    Thursday, September 29, 2005
    18 years ago
  • Date Issued
    Tuesday, May 25, 2010
    14 years ago
Abstract
A technique is provided for processing a physiological signal to compensate for artifacts. The technique includes identifying artifacts within the physiological signal. The technique also includes performing one or more multi-resolution decompositions, such as wavelet transformations, on the physiological signal and compensating for the identified artifacts in some or all of the respective decomposition components. The modified decomposition components may be reconstructed to generate an artifact-compensated signal which may be provided to a monitor or other device which is otherwise not configured to compensate for signal artifacts.
Description
BACKGROUND OF THE INVENTION

1. Field of the Invention


The present invention relates generally to the processing of waveform data and, more particularly, to the processing of waveforms associated with medical monitoring.


2. Description of the Related Art


This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present invention, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.


In the field of medicine, doctors often desire to monitor certain physiological characteristics of their patients. Accordingly, a wide variety of devices have been developed for monitoring physiological characteristics. Such devices provide doctors and other healthcare personnel with the information they need to provide the best possible healthcare for their patients. As a result, such monitoring devices have become an indispensable part of modern medicine.


One technique for monitoring certain physiological characteristics of a patient is commonly referred to as pulse oximetry, and the devices built based upon pulse oximetry techniques are commonly referred to as pulse oximeters. Pulse oximetry may be used to measure various blood flow characteristics, such as the blood-oxygen saturation of hemoglobin in arterial blood, the volume of individual blood pulsations supplying the tissue, and/or the rate of blood pulsations corresponding to each heartbeat of a patient.


The quality of these measurements, however, may be adversely affected by a number of factors such as patient motion, subdermal physiological structures, poor sensor operation or fit, poor signal reception and transmission, and so forth. Such factors may result in a pulse oximetry signal which contains artifacts or noise or is otherwise of low or reduced quality. When processed, such a low or reduced quality signal may result in physiological measurements being reported which may not be as accurate or reliable as desired.


To address this issue of poor signal quality, newer pulse oximetry monitors and/or systems may include algorithms, circuits, or other components to reduce, remove, or otherwise compensate for artifacts within the pulse oximetry signal. Such artifact compensation techniques, however, may be unavailable to health care providers using older or less advanced equipment that is not configured for artifact compensation. Since replacing older or less advanced pulse oximetry monitors and/or systems may not be financially feasible, a health care provider may have little choice but to continue using a system or monitor that does not compensate for artifacts in the acquired signal. However, even if an artifact compensating system is available, an older or less advanced system may still be useful within a health care facility. It may, therefore, be useful to provide artifact compensation in conjunction with the use of systems otherwise not configured to compensate for noise and artifacts with the pulse oximetry signal.


SUMMARY

Certain aspects commensurate in scope with the originally claimed invention are set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of certain forms the invention might take and that these aspects are not intended to limit the scope of the invention. Indeed, the invention may encompass a variety of aspects that may not be set forth below.


There is provided a method for processing a physiological signal, the method including the acts of: identifying one or more artifacts in a physiological signal; performing one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products; and compensating for the one or more artifacts in the two or more decomposition products to generate modified decomposition products.


There is provided one or more machine-readable media, including: a routine configured to identify one or more artifacts in a physiological signal; a routine configured to perform one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products; and a routine configured to compensate for the one or more artifacts in the two or more decomposition products to generate modified decomposition products.


There is provided a physiological monitoring system, including: a sensor configured to generate a physiological signal; and a monitor configured to receive an artifact-compensated signal derived from the physiological signal, wherein the artifact-compensated signal is generated by identifying one or more artifacts in the physiological signal, by performing one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products; by compensating for the one or more artifacts in the two or more decomposition products to generate modified decomposition products, and by reconstructing the modified decomposition products to generate the artifact-compensated signal.


There is provided a physiological sensor, including: an emitter configured to emit light; a detector configured to generate a signal in response to the emitted light; and one or more processing components configured to process the signal to generate an artifact-compensated signal.


There is provided a cable, including: one or more processing components configured to process an initial signal to generate an artifact-compensated signal.


There is provided an electronic device, including: one or more processing components configured to receive a signal generated by a physiological sensor, to process the signal to generate an artifact-compensated signal, and to transmit the artifact-compensated signal to a monitor which is not configured to perform artifact compensation





BRIEF DESCRIPTION OF THE DRAWINGS

Advantages of the invention may become apparent upon reading the following detailed description and upon reference to the drawings in which:



FIG. 1 illustrates a patient monitoring system coupled to a multi-parameter patient monitor and a sensor, in accordance with aspects of the present technique;



FIG. 2 is a diagram depicting components of a physiological signal processing system, in accordance with aspects of the present technique;



FIG. 3 is a flowchart of exemplary actions performed in accordance with aspects of the present technique;



FIG. 4A depicts a waveform representing a pulse oximetry signal to be processed in accordance with aspects of the present technique;



FIG. 4B depicts wavelet transformation of the waveform of FIG. 4A, in accordance with aspects of the present technique;



FIG. 4C depicts the wavelet vector of FIG. 4B modified to remove artifact signal, in accordance with aspects of the present technique; and



FIG. 4D depicts an output waveform reconstructed from the modified wavelet coefficients of FIG. 4C, in accordance with aspects of the present technique.





DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

One or more specific embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers' specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure.


It is desirable to provide a pulse oximeter signal (or other physiological monitor signal) from which the artifacts (such as may be generated by patient motion, subdermal physiological structures, poor sensor operation or fit, poor signal reception and transmission, and so forth) have been removed or reduced. Such a “clean” output signal may be provided as an input to a monitor or other display device which is not itself configured to compensate for signal noise or artifacts. The monitor or display device may display the clean signal or process the clean signal to generate one or more physiological characteristics of interest, such as measurements of blood oxygen level (SpO2), pulse rate, and so forth. In accordance with some aspects of the present technique, the artifact and noise compensation may be performed by processing components located on the sensor itself, on a cable disposed between the sensor and the monitor or display device, or on an intermediate device, such as a conversion unit or intermediate monitor.


Turning now to FIG. 1, an exemplary medical monitoring system that may benefit from the present technique is depicted. The exemplary system includes a physiological sensor 10 that may be attached to a patient. The sensor 10 generates an output signal based on a monitored physiological characteristic and transmits the output signal to a patient monitor 12. In the depicted embodiment, the sensor 10 is connected to the patient monitor 12 via a cable 14 suitable for transmission of the output signal as well as any other electrical and/or optical signals or impulses communicated between the sensor 10 and monitor 12. In accordance with aspects of the present technique, the sensor 10 and/or the cable 14 may include or incorporate one or more integrated circuit devices or electrical devices, such as a memory, processor chip, or resistor, that may facilitate or enhance communication between the sensor 10 and the patient monitor 12. Likewise the cable 14 may be an adaptor cable, with or without an integrated circuit or electrical device, for facilitating communication between the sensor 10 and various types of monitors, including older or newer versions of the patient monitor 12 or other physiological monitors. In other embodiments, the sensor 10 and the patient monitor 12 may communicate via wireless means, such as using radio, infrared, or optical signals. In such embodiments, a transmission device (not shown) may be connected to the sensor 10 to facilitate wireless transmission between the sensor 10 and the patient monitor 12.


In one embodiment, the patient monitor 12 may be a suitable pulse oximeter, such as those available from Nellcor Puritan Bennett Inc. In other embodiments, the patient monitor 12 may be a monitor suitable for measuring other physiological characteristics (such as tissue water fraction, tissue or blood carbon dioxide levels, and so forth) using spectrophotometric or other techniques. Furthermore, the monitor 12 may be a multi-purpose monitor suitable for performing pulse oximetry and/or other physiological and/or biochemical monitoring processes using data acquired via the sensor 10. Furthermore, to provide additional or enhanced functions to those performed by the monitor 12, the patient monitor 12 may be coupled to a multi-parameter patient monitor 16 via a cable 18 connected to a sensor input port and/or via a cable 20 connected to a digital communication port.


As noted above the data provided to the monitor 12 (or, alternatively, to the multi-parameter monitor 16) is generated at the sensor 10. In the example depicted in FIG. 1, the sensor 10 is an exemplary spectrophotometry sensor (such as a pulse oximetry sensor or probe) that includes an emitter 22 and a detector 24 which may be of any suitable type. For example, the emitter 22 may be one or more light emitting diodes adapted to transmit one or more wavelengths of light, such as in the red to infrared range, and the detector 24 may be a photodetector, such as a silicon photodiode package, selected to receive light in the range emitted from the emitter 22. In the depicted embodiment, the sensor 10 is coupled to a cable 14 through which electrical and/or optical signals may be transmitted to and/or from the emitter 22 and detector 24. The sensor 10 may be configured for use with the emitter and detector on the same side of the sensor site (i.e., as a “reflectance type” sensor) or on opposite sides of the sensor site (i.e., as a “transmission type” sensor). During operation, the emitter 22 shines one or more wavelengths of light through the patient's fingertip, or other tissue, and the light received by the detector 24 is processed to determine one or more physiological characteristics of the patient.


For example, for pulse oximetry applications the oxygen saturation of the patient's arterial blood (SaO2) may be determined using two or more wavelengths of light emitted by the emitter 22, most commonly red and near infrared wavelengths. After passage through the patient's tissue, a portion of the light emitted at these wavelengths is detected by the detector 24. The detector generates one or more signals, such an electrical or optical signals, in response to the amount of each wavelength that is detected at a given time. The generated signals may be digital or, where acquired as analog signals, may be digitized in implementations where digital processing and manipulation of the signals is employed. Such digitalization may be performed at the monitor 12 or prior to reaching the monitor 12. The signals, as noted above, may be transmitted via the cable 14 to the monitor 12, where the oxygen saturation or other physiological characteristic is calculated based on the signals. The signals may contain artifacts due to a variety of factors, such as light modulation by subdermal anatomic structures, patient motion during data acquisition, poor sensor operation or fit, poor signal reception and transmission, and so forth.


In one implementation of the present technique, the monitor 12 is not configured to compensate for artifacts in the data signal (such as a pulse oximetry signal) provided by the sensor 10. In such an implementation, one or more of the upstream devices or structures (such as sensor 10 and/or cable 14) may be configured to process the data to compensate for artifacts and to, thereby, generate a clean signal for processing or display by the monitor 12. Similarly, in another implementation, a downstream monitor, such as multi-parameter monitor 16 or a further downstream monitor, is not configured to compensate for artifacts in the signal. In such an implementation, the upstream devices or structures that may process the signal to compensate for artifacts may include not only the sensor 10 and/or cable 14, but also the monitors 12 or 16 and/or additional intermediate cables 18, 20. Similarly, other intermediate devices or structures may be disposed between the sensor 10 and the target monitor to process the data signal to compensate for artifacts, thereby generating a clean signal.


Referring now to FIG. 2, a box-diagram setting forth components used to process a signal to compensate for artifacts is set forth. In particular, a processing component 34 is depicted which is configured to receive an oximetry signal 36 containing artifacts and to compensate for the artifacts to produce a modified oximetry signal 38. The processing component 34 may be a general or special purpose processor or circuit suitable for incorporation into the desired structure, such as sensor 10 and/or cables 14, 18, or 20, as discussed above with regard to FIG. 1. Likewise, the processing component 34 may be a general or special purpose processor incorporated in the monitor 12, multi-parameter monitor 16, or other electronic device in the path along which the signal flows to a downstream destination that is not configured to compensate for signal artifacts.


While the processor component 34 may include hardware or circuitry designed to compensate for artifacts in the signal 36, the processor component 34 may also or alternately execute code or routines stored in a memory component 40 to accomplish the desired artifact compensation. The memory component 40 may be within the same device or structure as the processing component 34 or may be within a different structure or device in communication with the processing component 34. Such a memory components 40 may include solid state or integrated circuit type memory devices or other suitable memory devices, such as magnetic or optical media and/or drives suitable for use in the desired structure or device. As noted above, such processing components 34 and/or memory components 40 may be incorporated into the sensor 10, cables 14, 18, and 20, or the monitors 12, and 16.



FIG. 2 generally depicts that the signal 36 with artifacts is provided to the processing component 34 for artifact compensation. It is also possible, however, that the signal 36 is provided initially to the memory component 40 for subsequent processing by the processing component 34, as denoted by dotted line 42. Similarly, though the modified signal 38 may be directly output by the processing component 34 to a downstream location, it may also be stored temporarily by the memory component 40 prior to subsequent downstream transmission, as depicted by dotted line 44.


In an embodiment of the present technique, a data signal containing artifacts is processed to compensate for those artifacts and may, subsequently, be provided to a monitor or other system that is otherwise not configured to compensate for artifacts in the signal. An example of such an embodiment is set forth in FIG. 3, depicting an artifact compensation technique 60 for use with a physiological signal. In this example, an oximetry data signal 36, such as a plethysmographic waveform, is processed to remove artifacts.


In this example, the oximetry signals 36 are processed to identify artifacts 64 within the signal (block 62). Identification of the artifacts 64 at block 62 may be accomplished by conventional artifact identification algorithms or techniques, such as may be implemented in advanced oximetry monitors or other processor-based systems commercially available or proprietary. In accordance with the present technique, these artifact identification techniques or algorithms may be implemented, as discussed above, by one or more processing components 34. These processing components 34 may be disposed within the sensor 10 itself, within the cables 14, 18, or 20 intermediate between the sensor 10 and a target monitor, and/or within an intervening monitor, such as patient monitor 12 or multi-parameter monitor 16, or other electronic device. For example, in one embodiment, the artifact identification of block 62 includes the timing and frequency of artifacts 64. This time and frequency information may be used to locate the corresponding portion of signal components within one or more wavelet decomposition levels (as discussed below) to compensate for the respective artifacts 64.


In addition, the oximetry signals 36 may be processed using a multi-resolution decomposition technique (block 66), such as wavelet decomposition by discrete wavelet transformation using a filter bank. Though wavelet transformation is discussed generally herein, those of ordinary skill in the art will appreciate that other transformation techniques capable of providing the desired time and frequency information may also be employed and are within the scope of the present technique.


As mentioned above with regard to artifact identification, the decomposition of the signal 36 may be accomplished by suitable decomposition algorithms or techniques implemented by one or more processing components 34. These processing components 34 may be disposed within the sensor 10 itself, within the cables 14, 18, or 20 intermediate between the sensor 10 and a target monitor, and/or within an intervening monitor, such as patient monitor 12 or multi-parameter monitor 16, or other electronic device. The one or more processing components 34 that implement signal decomposition may be same or different than the processing components 34 that implement artifact identification, as discussed above. Furthermore, though FIG. 3 depicts decomposition (block 66) and artifact extraction (62) implemented in parallel, other embodiments are also possible. For example, as will be appreciated by those of ordinary skill in the art, decomposition (block 66) and artifact extraction (block 62) may be implemented sequentially or in series as well.


In a wavelet decomposition implementation, each iteration of decomposition yields a low-passed signal component and a high-passed signal component represented as wavelet coefficients 68. As will be appreciated by those of ordinary skill in the art, the low-passed component generally corresponds to an approximation of the signal undergoing decomposition while the high-passed component generally corresponds to detail components of the signal undergoing decomposition. In one iterative implementation, each iteration, i.e., resolution level, of the decomposition decomposes the previous approximation, i.e., low-passed component, to generate an approximation and detail component representative of the previous approximation. In other words, the low-passed component of the previous resolution level is decomposed to yield high and low-passed components at the current resolution level. Because the low-passed components are iteratively decomposed in such an implementation, each previous resolution level may be reproduced by reintegrating the low and high-passed components (i.e., the approximation and details) of the current resolution level. Similarly, the initial signal may be reproduced by reintegrating the current resolution level of approximation and details along with previous resolution levels of detail.


During or subsequent to wavelet decomposition, some or all of the high and/or low-resolution filtered components generated at some or all of the decomposition resolution levels may be processed (block 70) to compensate for artifact signal, thereby generating modified wavelet coefficients 72. For example, the timing and frequency information for the artifacts 64 identified at block 62 may be used to deduct, remove, or modify the respective wavelet decomposition coefficients, such as during signal reconstruction, to compensate for the artifacts 64. In one embodiment, artifact compensation modifies the low-passed components (i.e., approximations) and/or the high-passed components (i.e., the details) based on the frequency and/or time information associated with the identified artifacts 64 to compensate for portions of the signal attributable to the artifacts 64 in the modified coefficients 72.


For example, in one embodiment, the oximetry signal 36 undergoes a three-stage wavelet decomposition to generate the respective high and low-passed components. In this example, artifact compensation is applied to the two high-passed bands of the three-stage decomposition to generate modified coefficients in these two bands. The artifact compensation process may involve setting applicable coefficients or portions of the signal corresponding to an artifact 64 to zero or otherwise reducing the magnitude of the applicable coefficients or portions of the signal. In this manner, the level of detail in the reconstructed signal may be reduced based on the likely correspondence of the detail level to artifacts or noise instead of to physiological signal.


The modified wavelet coefficients 72 generated by artifact compensation may be reconstructed (block 74), such as by an inverse wavelet transform, to generate a clean or artifact-compensated waveform 76. In such an embodiment, the inverse wavelet transform preserves the original physiological data while allowing artifact compensation, as opposed to techniques using synthesized waveforms (such as triangular synthetic waveforms) where physiological information may be lost. This clean waveform 76, in turn, may be processed to determine (block 78) one or more physiological characteristics of interest, such as respiratory information, blood oxygen saturation, pulse rate, and so forth. In one embodiment, the clean waveform is provided to and processed by a monitor or other electronic device that is not configured to compensate for artifacts itself. Though the preceding discussion generally discusses decomposition using wavelet transformation, other decomposition techniques that generate time-frequency and/or time-scale components may also be used in accordance with the present technique.


Referring now to FIGS. 4A-4D, example waveforms representative of the technique set forth in FIG. 3 are provided for the purpose of illustration. FIG. 4A depicts an oximetry signal 36, as provide in FIG. 3. The signal 36 of FIG. 4A contains artifacts to be compensated. FIG. 4B depicts a three-stage wavelet decomposition 82 of the original signal 36. The three-stage decomposition 82 includes a first high-passed component 84. The first low-passed component was further decomposed to yield a second high-passed component 86 and a second low-passed component that was in turn subsequently decomposed to generate a third low-passed component 88 and a third high-passed component 90. The third low-passed component 88 represents the approximation data for the original signal while the first, second, and third high-passed components 84, 86, 90 represent different levels of detail. FIG. 4C depicts the modified wavelet vector 92 after artifact compensation on the three-stage decomposition 82. In this example, the first and second low-passed bands 84 and 86 correspond to the identified artifact 64 and are set to zero (i.e. removed) in the modified wavelet vector 92, as depicted. The modified wavelet vector 92 provides the wavelet coefficients 72 that may be reconstructed, such as by an inverse wavelet transform, to generate a modified signal 76, such as the depicted output waveform. Artifacts present in the original signal 36 are compensated for in the modified signal 76. The modified signal 76 may be provided to subsequent processes for the determination of physiological characteristics of interest, such as blood oxygen saturation, pulse rate and so forth.


While the invention may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and have been described in detail herein. However, it should be understood that the invention is not intended to be limited to the particular forms disclosed. Rather, the invention is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention as defined by the following appended claims. Indeed, the present techniques may not only be applied to pulse oximetry, but also to other physiological monitor outputs as well.

Claims
  • 1. A method for processing a physiological signal, the method performed on a processing component and comprising the acts of: independently, identifying one or more artifacts in a physiological signal and performing one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products; andcompensating for the one or more artifacts in the two or more decomposition products to generate modified decomposition products.
  • 2. The method of claim 1, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 3. The method of claim 1, wherein the two or more decomposition products comprise wavelet coefficients.
  • 4. The method of claim 1, comprising reconstructing the modified decomposition products to generate an artifact-compensated signal.
  • 5. The method of claim 4, comprising processing the artifact-compensated signal at a downstream device to derive one or more physiological characteristics of interest.
  • 6. The method of claim 5, wherein the downstream device is not configured to perform artifact compensation.
  • 7. The method of claim 1, wherein the physiological signal is a waveform.
  • 8. The method of claim 1, wherein the one or more multi-resolution decompositions comprise one or more wavelet decompositions.
  • 9. The method of claim 1, wherein the physiological signal comprises a pulse oximetry signal.
  • 10. The method of claim 1, wherein the one or more multi-resolution decompositions are implemented as a filter bank.
  • 11. One or more tangible machine-readable media, comprising routines, which when executed by a processor: independently, identify one or more artifacts in a physiological signal and perform one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products; andcompensate for the one or more artifacts in the two or more decomposition products to generate modified decomposition products.
  • 12. The one or more tangible machine-readable media of claim 11, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 13. The one or more tangible machine-readable media of claim 11, wherein the two or more decomposition products comprise wavelet coefficients.
  • 14. The one or more tangible machine-readable media of claim 11, comprising a routine configured to reconstruct the modified decomposition products to generate an artifact-compensated signal.
  • 15. The one or more tangible machine-readable media of claim 14, wherein the routine configured to reconstruct the modified decomposition products performs an inverse wavelet transform of one or more modified wavelet coefficients.
  • 16. The one or more tangible machine-readable media of claim 11, wherein the one or more multi-resolution decompositions are implemented as a filter bank.
  • 17. A physiological monitoring system, comprising: a sensor configured to generate a physiological signal;a processing component configured to generate an artifact-compensated signal by independently, identifying one or more artifacts in the physiological signal and performing one or more multi-resolution decompositions on the physiological signal to generate two or more decomposition products, by compensating for the one or more artifacts in the two or more decomposition products to generate modified decomposition products, and by reconstructing the modified decomposition products to generate the artifact-compensated signal; anda monitor configured to display the artifact-compensated signal.
  • 18. The physiological monitoring system of claim 17, wherein the processing component is provided as part of the sensor, one or more cables connecting the sensor and the monitor, an intermediate monitor disposed between the sensor and the monitor, or a conversion device disposed between the sensor and the monitor.
  • 19. The physiological monitoring system of claim 17, wherein the artifact-compensated signal is generated by one or more processing components disposed within the sensor or between the sensor and the monitor.
  • 20. The physiological monitoring system of claim 17, wherein the monitor is further configured to process the artifact-compensated signal to derive one or more physiological characteristics of interest.
  • 21. The physiological monitoring system of claim 17, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 22. The physiological monitoring system of claim 17, wherein the two or more decomposition components comprise wavelet coefficients.
  • 23. The physiological monitoring system of claim 17, wherein the monitor is not configured to perform artifact compensation.
  • 24. The physiological monitoring system of claim 17, wherein the sensor comprises a pulse oximetry sensor.
  • 25. The physiological monitoring system of claim 17, wherein the monitor comprises a pulse oximetry monitor or a multi-parameter monitor.
  • 26. The physiological monitoring system of claim 17, wherein the one or more multi-resolution decompositions comprise one or more wavelet decompositions.
  • 27. A physiological sensor, comprising: an emitter configured to emit light;a detector configured to generate a signal in response to the emitted light; andone or more processing components configured to independently, identify one or more artifacts in the signal and perform one or more multi-resolution decompositions on the signal to generate two or more decomposition products, to compensate for the one or more artifacts in the two or more decomposition products to generate modified decomposition products, and to reconstruct the modified decomposition products to generate an artifact-compensated signal.
  • 28. The physiological sensor of claim 27, wherein the emitter comprises one or more light emitting diodes.
  • 29. The physiological sensor of claim 27, wherein the detector comprises one or more photodetectors.
  • 30. The physiological sensor of claim 27, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 31. The physiological sensor of claim 27, wherein the two or more decomposition components comprise wavelet coefficients.
  • 32. The physiological sensor of claim 27, wherein the one or more multi-resolution decompositions comprise one or more wavelet decompositions.
  • 33. The physiological sensor of claim 27, wherein the sensor comprises a pulse oximetry sensor.
  • 34. A cable configured to connect two electronic devices, comprising: one or more processing components configured to independently, identify one or more artifacts in an initial signal received from a first of the electronic devices and perform one or more multi-resolution decompositions on the initial signal to generate two or more decomposition products, to compensate for the one or more artifacts in the two or more decomposition products to generate modified decomposition products, and to reconstruct the modified decomposition products to generate an artifact-compensated signal configured for output to a second of the electronic devices.
  • 35. The cable of claim 34, wherein the cable connects a physiological sensor to a physiological monitor.
  • 36. The cable of claim 35, wherein the physiological sensor comprises a pulse oximetry sensor.
  • 37. The cable of claim 36, wherein the physiological monitor comprises one of a pulse oximetry monitor or a multi-parameter monitor.
  • 38. The cable of claim 34, wherein the cable connects a first monitor to a second monitor.
  • 39. The cable of claim 38, wherein the first monitor comprises a pulse oximetry monitor and the second monitor comprises a multi-parameter monitor.
  • 40. The cable of claim 34, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 41. The cable of claim 34, wherein the two or more decomposition components comprise wavelet coefficients.
  • 42. The cable of claim 34, wherein the one or more multi-resolution decompositions comprise one or more wavelet decompositions.
  • 43. An electronic device, comprising: one or more processing components configured to receive a signal generated by a physiological sensor, to independently, identify one or more artifacts in the signal and perform one or more multi-resolution decompositions on the signal to generate two or more decomposition products, to compensate for the one or more artifacts in the two or more decomposition products to generate modified decomposition products, and to reconstruct the modified decomposition products to generate an artifact-compensated signal, and to transmit the artifact-compensated signal to a monitor which is not configured to perform artifact compensation.
  • 44. The electronic device of claim 43, wherein the electronic device comprises a physiological monitor.
  • 45. The electronic device of claim 44, wherein the physiological monitor comprises one of a pulse oximetry monitor or a multi-parameter monitor.
  • 46. The electronic device of claim 43, wherein the physiological sensor comprises a pulse oximetry sensor.
  • 47. The electronic device of claim 43, wherein the monitor comprises one of a pulse oximetry monitor or a multi-parameter monitor.
  • 48. The electronic device of claim 43, wherein the two or more decomposition components comprise high-passed and low-passed signal components.
  • 49. The electronic device of claim 43, wherein the two or more decomposition components comprise wavelet coefficients.
  • 50. The electronic device of claim 43, wherein the one or more multi-resolution decompositions comprise one or more wavelet decompositions.
US Referenced Citations (246)
Number Name Date Kind
3638640 Shaw Feb 1972 A
4714341 Hamaguri et al. Dec 1987 A
4805623 Jöbsis Feb 1989 A
4807631 Hersh et al. Feb 1989 A
4911167 Corenman et al. Mar 1990 A
4913150 Cheung et al. Apr 1990 A
4936679 Mersch Jun 1990 A
4938218 Goodman et al. Jul 1990 A
4971062 Hasebe et al. Nov 1990 A
4972331 Chance Nov 1990 A
4974591 Awazu et al. Dec 1990 A
5028787 Rosenthal et al. Jul 1991 A
5065749 Hasebe et al. Nov 1991 A
5084327 Stengel Jan 1992 A
5119815 Chance Jun 1992 A
5122974 Chance Jun 1992 A
5167230 Chance Dec 1992 A
5190038 Polson et al. Mar 1993 A
5246003 DeLonzor Sep 1993 A
5247931 Norwood Sep 1993 A
5263244 Centa et al. Nov 1993 A
5275159 Griebel Jan 1994 A
5279295 Martens et al. Jan 1994 A
5297548 Pologe Mar 1994 A
5355880 Thomas et al. Oct 1994 A
5372136 Steuer et al. Dec 1994 A
5385143 Aoyagi Jan 1995 A
5390670 Centa et al. Feb 1995 A
5413099 Schmidt et al. May 1995 A
5469845 DeLonzor et al. Nov 1995 A
5482036 Diab et al. Jan 1996 A
5483646 Uchikoga Jan 1996 A
5521851 Wei et al. May 1996 A
5553614 Chance Sep 1996 A
5564417 Chance Oct 1996 A
5575285 Takanashi et al. Nov 1996 A
5611337 Bukta Mar 1997 A
5630413 Thomas et al. May 1997 A
5645059 Fein et al. Jul 1997 A
5645060 Yorkey Jul 1997 A
5680857 Pelikan et al. Oct 1997 A
5692503 Keunstner Dec 1997 A
5730124 Yamauchi Mar 1998 A
5758644 Diab et al. Jun 1998 A
5779631 Chance Jul 1998 A
5782757 Diab et al. Jul 1998 A
5786592 Hök Jul 1998 A
5830136 DeLonzor et al. Nov 1998 A
5830139 Abreu Nov 1998 A
5831598 Kauffert et al. Nov 1998 A
5842981 Larsen et al. Dec 1998 A
5871442 Madarasz et al. Feb 1999 A
5873821 Chance et al. Feb 1999 A
5920263 Huttenhoff et al. Jul 1999 A
5995855 Kiani et al. Nov 1999 A
5995856 Mannheimer et al. Nov 1999 A
5995859 Takahashi Nov 1999 A
6011986 Diab et al. Jan 2000 A
6064898 Aldrich May 2000 A
6081742 Amano et al. Jun 2000 A
6088607 Diab et al. Jul 2000 A
6094592 Yorkey et al. Jul 2000 A
6120460 Abreu Sep 2000 A
6134460 Chance Oct 2000 A
6150951 Olejniczak Nov 2000 A
6154667 Miura et al. Nov 2000 A
6163715 Larsen et al. Dec 2000 A
6181958 Steuer et al. Jan 2001 B1
6181959 Schöllermann et al. Jan 2001 B1
6222189 Misner et al. Apr 2001 B1
6230035 Aoyagi et al. May 2001 B1
6266546 Steuer et al. Jul 2001 B1
6285895 Ristolainen et al. Sep 2001 B1
6312393 Abreu Nov 2001 B1
6353750 Kimura et al. Mar 2002 B1
6361501 Takeshi Mar 2002 B1
6393311 Edgar, Jr. et al. May 2002 B1
6397091 Diab et al. May 2002 B2
6415236 Kobayashi et al. Jul 2002 B2
6419671 Lemberg Jul 2002 B1
6438399 Kurth Aug 2002 B1
6461305 Schnall Oct 2002 B1
6466809 Riley Oct 2002 B1
6487439 Skladnev et al. Nov 2002 B1
6501974 Huiku Dec 2002 B2
6501975 Diab et al. Dec 2002 B2
6519486 Edgar, Jr. et al. Feb 2003 B1
6526301 Larsen et al. Feb 2003 B2
6544193 Abreu Apr 2003 B2
6546267 Sugiura et al. Apr 2003 B1
6549795 Chance Apr 2003 B1
6580086 Schulz et al. Jun 2003 B1
6584336 Ali et al. Jun 2003 B1
6591122 Schmitt Jul 2003 B2
6594513 Jobsis et al. Jul 2003 B1
6606509 Schmitt Aug 2003 B2
6606511 Ali et al. Aug 2003 B1
6615064 Aldrich Sep 2003 B1
6618042 Powell Sep 2003 B1
6622095 Kobayashi et al. Sep 2003 B2
6650918 Terry Nov 2003 B2
6654621 Palatnik et al. Nov 2003 B2
6654623 Kastle Nov 2003 B1
6654624 Diab et al. Nov 2003 B2
6658276 Kianl et al. Dec 2003 B2
6658277 Wasserman Dec 2003 B2
6662030 Khalil et al. Dec 2003 B2
6668183 Hicks et al. Dec 2003 B2
6671526 Aoyagi et al. Dec 2003 B1
6671528 Steuer et al. Dec 2003 B2
6678543 Diab et al. Jan 2004 B2
6684090 Ali et al. Jan 2004 B2
6690958 Walker et al. Feb 2004 B1
6697658 Al-Ali Feb 2004 B2
6701170 Stetson Mar 2004 B2
6708048 Chance Mar 2004 B1
6711424 Fine et al. Mar 2004 B1
6711425 Reuss Mar 2004 B1
6714245 Ono Mar 2004 B1
6731274 Powell May 2004 B2
6785568 Chance Aug 2004 B2
6793654 Lemberg Sep 2004 B2
6801797 Mannheimer et al. Oct 2004 B2
6801798 Geddes et al. Oct 2004 B2
6801799 Mendelson Oct 2004 B2
6810277 Edgar, Jr. et al. Oct 2004 B2
6829496 Nagai et al. Dec 2004 B2
6850053 Daalmans et al. Feb 2005 B2
6863652 Huang et al. Mar 2005 B2
6873865 Steuer et al. Mar 2005 B2
6889153 Dietiker May 2005 B2
6898451 Wuori May 2005 B2
6931269 Terry Aug 2005 B2
6939307 Dunlop Sep 2005 B1
6947780 Scharf Sep 2005 B2
6949081 Chance Sep 2005 B1
6961598 Diab Nov 2005 B2
6983178 Fine et al. Jan 2006 B2
6987994 Mortz Jan 2006 B1
6993371 Kiani et al. Jan 2006 B2
6996427 Ali et al. Feb 2006 B2
7020507 Scharf et al. Mar 2006 B2
7024235 Melker et al. Apr 2006 B2
7027849 Al-Ali Apr 2006 B2
7030749 Al-Ali Apr 2006 B2
7035679 Addison et al. Apr 2006 B2
7035697 Brown Apr 2006 B1
7047056 Hannula et al. May 2006 B2
7072702 Edgar, Jr. et al. Jul 2006 B2
7079880 Stetson Jul 2006 B2
7127278 Melker et al. Oct 2006 B2
7162306 Caby et al. Jan 2007 B2
7209775 Bae et al. Apr 2007 B2
7215984 Diab et al. May 2007 B2
7215986 Diab et al. May 2007 B2
7225013 Geva et al. May 2007 B2
7236811 Schmitt Jun 2007 B2
7254433 Diab et al. Aug 2007 B2
7263395 Chan et al. Aug 2007 B2
7272426 Schmid Sep 2007 B2
7328053 Diab et al. Feb 2008 B1
7336982 Yoo Feb 2008 B2
7343187 Stetson Mar 2008 B2
7373193 Al-Ali et al. May 2008 B2
7376453 Diab et al. May 2008 B1
7383070 Diab et al. Jun 2008 B2
7398115 Lynn Jul 2008 B2
7515949 Norris Apr 2009 B2
20010005773 Larsen et al. Jun 2001 A1
20010020122 Steuer et al. Sep 2001 A1
20010039376 Steuer et al. Nov 2001 A1
20010044700 Kobayashi et al. Nov 2001 A1
20020026106 Khalil et al. Feb 2002 A1
20020035318 Mannheimer et al. Mar 2002 A1
20020038079 Steuer et al. Mar 2002 A1
20020042558 Mendelson Apr 2002 A1
20020049389 Abreu Apr 2002 A1
20020062071 Diab et al. May 2002 A1
20020111748 Kobayashi et al. Aug 2002 A1
20020133068 Huiku Sep 2002 A1
20020156354 Larson Oct 2002 A1
20020161287 Schmitt Oct 2002 A1
20020161290 Chance Oct 2002 A1
20020165439 Schmitt Nov 2002 A1
20020198443 Ting Dec 2002 A1
20030023140 Chance Jan 2003 A1
20030055324 Wasserman Mar 2003 A1
20030060693 Monfre et al. Mar 2003 A1
20030139687 Abreu Jul 2003 A1
20030144584 Mendelson Jul 2003 A1
20030220548 Schmitt Nov 2003 A1
20030220576 Diab Nov 2003 A1
20030225337 Scharf et al. Dec 2003 A1
20040010188 Wasserman Jan 2004 A1
20040054270 Pewzner et al. Mar 2004 A1
20040054281 Adam et al. Mar 2004 A1
20040059210 Stetson Mar 2004 A1
20040087846 Wasserman May 2004 A1
20040107065 Al-Ali Jun 2004 A1
20040127779 Steuer et al. Jul 2004 A1
20040171920 Mannheimer et al. Sep 2004 A1
20040176670 Takamura et al. Sep 2004 A1
20040176671 Fine et al. Sep 2004 A1
20040193065 Houben Sep 2004 A1
20040230106 Schmitt et al. Nov 2004 A1
20050033129 Edgar, Jr. et al. Feb 2005 A1
20050049470 Terry Mar 2005 A1
20050080323 Kato Apr 2005 A1
20050101850 Parker May 2005 A1
20050113651 Wood et al. May 2005 A1
20050113656 Chance May 2005 A1
20050168722 Forstner et al. Aug 2005 A1
20050177034 Beaumont Aug 2005 A1
20050192488 Bryenton et al. Sep 2005 A1
20050192493 Wuori Sep 2005 A1
20050203357 Debreczeny et al. Sep 2005 A1
20050209517 Diab et al. Sep 2005 A1
20050228248 Dietiker Oct 2005 A1
20050267346 Faber et al. Dec 2005 A1
20050283059 Iyer et al. Dec 2005 A1
20060009688 Lamego et al. Jan 2006 A1
20060015021 Cheng Jan 2006 A1
20060020181 Schmitt Jan 2006 A1
20060030763 Mannheimer et al. Feb 2006 A1
20060052680 Diab Mar 2006 A1
20060058683 Chance Mar 2006 A1
20060064024 Schnall Mar 2006 A1
20060195028 Hannula et al. Aug 2006 A1
20060200016 Diab et al. Sep 2006 A1
20060211930 Scharf et al. Sep 2006 A1
20060217609 Diab et al. Sep 2006 A1
20060224058 Mannheimer Oct 2006 A1
20060247501 Ali Nov 2006 A1
20060258921 Addison et al. Nov 2006 A1
20060258927 Edgar, Jr. et al. Nov 2006 A1
20060293574 Norris Dec 2006 A1
20070004977 Norris Jan 2007 A1
20070213621 Reisfeld et al. Sep 2007 A1
20070213622 Reisfeld Sep 2007 A1
20070225581 Diab et al. Sep 2007 A1
20070249918 Diab et al. Oct 2007 A1
20070291832 Diab et al. Dec 2007 A1
20080004514 Diab et al. Jan 2008 A1
20080033266 Diab et al. Feb 2008 A1
20080036752 Diab et al. Feb 2008 A1
20080045823 Diab et al. Feb 2008 A1
Foreign Referenced Citations (25)
Number Date Country
19640807 Sep 1997 DE
0630203 Dec 1994 EP
3170866 Jul 1991 JP
3238813 Oct 1991 JP
4191642 Jul 1992 JP
4332536 Nov 1992 JP
10216115 Aug 1998 JP
2003210438 Jul 2003 JP
2003275192 Sep 2003 JP
2003339678 Dec 2003 JP
2004135854 May 2004 JP
2004202190 Jul 2004 JP
WO9221281 Dec 1992 WO
WO9403102 Feb 1994 WO
WO9512349 May 1995 WO
WO9749330 Dec 1997 WO
WO9842249 Oct 1998 WO
WO9842251 Oct 1998 WO
WO9932030 Jul 1999 WO
WO0021438 Apr 2000 WO
WO0125802 Apr 2001 WO
WO03000125 Jan 2003 WO
WO 2004075746 Sep 2004 WO
WO2004075746 Sep 2004 WO
WO2005009221 Feb 2005 WO
Related Publications (1)
Number Date Country
20070073124 A1 Mar 2007 US