# Patent

## Title
System and method for linking patient data to a patient and providing sensor quality assurance

## Abstract

The present disclosure is generally directed to maintaining sensor quality standards and/or preventing improper remanufacture of sensors, such as pulse oximetry sensors. Present embodiments may include a system for facilitating the monitoring of physiologic conditions that includes an optical reader configured to translate an optical machine-readable representation of data associated with a patient into electronic data, a memory device configured to receive and store the electronic data after an initial reading of the machine-readable representation of data by the optical reader, and a processor configured to associate the electronic data with historical data obtained from the patient and limit access to the historical data based on whether the optical reader provides matching electronic data based on a subsequently read optical machine-readable representation of data when predefined conditions are met.

## Background
CROSS-REFERENCE TO RELATED APPLICATIONS
The present disclosure is related to co-pending U.S. patent application Ser. No. 12/495,007, entitled “System and Method for Providing Sensor Quality Assurance,” and to co-pending U.S. patent application Ser. No. 12/494,986, entitled “System and Method for Controlling One or Both of Sensor Functionality and Data Access Based on Biometrics Data,” each of which is herein incorporated by reference in its entirety for all purposes. Both co-pending applications are concurrently filed with and include the same inventors as the present application.
BACKGROUND
The present disclosure relates generally to physiological monitoring instruments and, in particular, to a sensor that cooperates with a patient identifier to link patient data with a patient and provide quality assurance by linking the patient identifier to the sensor.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, 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 disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
There are numerous techniques and systems for monitoring a patient's physiology. For example, pulse oximetry may be used to continuously monitor physiologic characteristics of a patient. Pulse oximetry may generally be defined as a non-invasive technique that facilitates monitoring of a patient's blood characteristics For example, pulse oximetry may be used to measure blood oxygen saturation of hemoglobin in a patient's arterial blood and/or the patient's heart rate. Specifically, in pulse oximetry, blood characteristic measurements may be acquired using a non-invasive sensor that passes light through a portion of a patient's blood perfused tissue and that photoelectrically senses the absorption and scattering of light through the blood perfused tissue. Various wavelengths of light may be used that may or may not pass through certain blood constituents. Indeed, a typical pulse oximetry sensor includes at least two light emitters that emit different wavelengths of light, and a light detector. Based on how much light at certain wavelengths is emitted and detected, and based on absorption and scattering characteristics of certain blood constituents, an estimate of the blood content may be made based on the detection results. For example, a typical signal resulting from the sensed light may be referred to as a plethysmographic waveform, which is a measurement of the absorbed and scattered light at different wavelengths.
Once acquired, the plethysmographic waveform may be used with various algorithms to estimate an amount of blood constituent in the tissue, as well as other physiologic characteristics. This and other types of data may be collected over time to provide trend data or historical data for a patient. This trend data or historical data may be stored for use in assessing a patient's condition, reviewing a patient's progress, or the like. However, it is now recognized that such stored data can potentially be disassociated with a patient. For example, the data may be stored on a device or system that is used to monitor multiple patients, and the data for a particular patient may be confused with that of a different patient having been monitored or otherwise addressed by the device or system. Accordingly, it is now recognized that a technique for creating a strong association between such data and the appropriate patient may be desirable.
Some conventional sensors, such as conventional pulse oximetry sensors, may include an information element that stores information that can be read by a monitoring device to facilitate proper use of the sensor. For example, a pulse oximeter sensor may include a memory or a resistor that can be read by an oximeter. The information stored on the information element may include parameters about the sensor. For example, with regard to a pulse oximeter sensor, the information may indicate sensor type (e.g., neonatal, pediatric, or adult), the wavelengths of light produced by the emitters, and so forth. Certain data stored in the pulse oximeter sensor, such as the wavelengths of light associated with the emitters of the sensor, may be important for proper blood characteristic measurement. This information may be utilized in algorithms for determining values for one or more measured blood characteristics. Further, the information element may be utilized for security and quality control purposes. For example, the information element may ensure proper operation by preventing the sensor from functioning with improperly configured or unauthorized devices.
Due to the function of the information element, it is often necessary for sensor operation. Accordingly, the information element is often included in unapproved remanufactured sensors to enable their operation. However, such unauthorized remanufactured sensors may be unreliable and fail to function properly. Indeed, improper remanufacturing of a sensor or tampering with the sensor can impact the quality and reliability of the sensor, especially when such sensors include an information element with pertinent operational data stored thereon. For example, improper remanufacturing of a sensor may result in consistently incorrect measurements and/or cause malfunctions by coupling incompatible sensor components together. In a specific example, an information element for a neonatal oximeter sensor may be improperly incorporated into the body of an adult oximeter sensor during remanufacture. Thus, the information element incorporated into the remanufactured sensor may include settings for a neonatal application that do not correspond to the wavelengths associated with the light emitters of the remanufactured sensor, which correspond to an adult application. Such remanufacturing can cause improper operation and incorrect measurement of physiological characteristics.



BRIEF DESCRIPTION OF THE DRAWINGS
Advantages of present embodiments may become apparent upon reading the following detailed description and upon reference to the drawings in which:
FIG. 1 is a perspective view of a patient physiological data measurement system in accordance with an exemplary embodiment of the present disclosure;
FIG. 2 illustrates an armband including an optical machine-readable representation of data in accordance with an exemplary embodiment of the present disclosure;
FIG. 3 is a perspective view of a patient physiological data measurement system including an attached optical reader in accordance with an exemplary embodiment of the present disclosure;
FIG. 4 illustrates a front view and a back view of a sensor including an optical machine-readable representation of data printed on the back in accordance with an exemplary embodiment of the present disclosure;
FIG. 5 illustrates a sensor with an attached tag, wherein the tag includes an optical machine-readable representation of data printed thereon in accordance with an exemplary embodiment of the present disclosure;
FIG. 6 illustrates a sensor with an optical machine-readable representation of data printed on a cable of the sensor in accordance with an exemplary embodiment of the present disclosure;
FIG. 7 illustrates a sensor including a loosely attached layer with an optical machine-readable representation of data printed thereon in accordance with an exemplary embodiment of the present disclosure;
FIG. 8 illustrates a sensor including an expansive bandage layer positioned over a sensor body, wherein the bandage layer includes an optical machine-readable representation of data printed thereon in accordance with an exemplary embodiment of the present disclosure;
FIG. 9 illustrates a sensor and a separate band attached to a clear plastic layer to facilitate attachment of the sensor and the band to a patient such that the sensor and band are separate, wherein the band includes an optical machine-readable representation of data printed thereon in accordance with an exemplary embodiment of the present disclosure;
FIG. 10 illustrates a sensor and an armband attached together and then detached with the armband attached to a patient, wherein the armband includes an optical machine-readable representation of data printed thereon in accordance with an exemplary embodiment of the present disclosure;
FIG. 11 illustrates a sensor with an optical machine-readable representation of data printed on a detachable portion of a sensor bandage in accordance with an exemplary embodiment of the present disclosure; and
FIG. 12 illustrates a sensor with a bandage including an optical machine-readable representation of data printed in two different types of ink in accordance with an exemplary embodiment of the present disclosure.



DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS
One or more specific embodiments of the present disclosure 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.
Embodiments of the present disclosure relate, in general, to a sensor for measuring patient physiological characteristics. For example, present embodiments may include a pulse oximeter sensor that functions to measure oxygen content in a patient's blood. More particularly, present embodiments are directed to sensor designs and corresponding hardware and/or software that facilitate associating patient data with a particular patient and preventing remanufacture of the sensor or making such remanufacture impractical. Indeed, it is now recognized that a strong association of patient data with the appropriate patient is desirable. Further, it is now recognized that unauthorized remanufacture of a sensor can create issues with proper operation of the sensor, and, thus, it is desirable to prevent such practices. Accordingly, present embodiments are directed to improving sensor quality assurance by preventing sensor remanufacture.
Specifically, embodiments of the present disclosure relate to a system including a sensor and a patient identification (ID) tag, which may be a component of the sensor. The sensor may include a functional component that is configured to cooperate with the patient ID tag to associate patient data with a patient and improve sensor quality assurance. The patient ID tag may be configured to attach to a patient and may include an optical machine-readable representation of data (OMRD), such as a barcode. In accordance with present embodiments, the functional component (e.g., a memory) and the OMRD may cooperate to link patient-specific data to the appropriate patient via the patient ID tag (e.g., a patient ID bracelet), which may be physically attached to the appropriate patient. Further, the functional component and the OMRD may substantially prevent remanufacture of the sensor by, for example, preventing operation of the sensor without a correspondence between data represented by the OMRD and data stored on the sensor.
In accordance with present embodiments, patient-specific data (e.g., physiologic trend data acquired over time for a particular patient) may be stored in a sensor memory or in a central storage system, such as a computer network of a hospital. When such data is stored in the sensor itself, it may be desirable to keep the sensor attached to the patient as the patient is moved around the hospital. Indeed, this may allow the patient's historical data to go with the patient to different monitors in different areas of the hospital. Similarly, having such data available on a central network may facilitate access to a patient's data as the patient is moved around.
Present embodiments provide a system and technique for confirmation of the patient's identity and/or authenticity of a sensor assigned to the patient. For example, a patient ID tag may be assigned to the patient in the form of an OMRD, such as a barcode, printed on a component of the sensor or on an armband that is attached to the patient. The OMRD on the patient ID tag, the sensor, and/or information obtained by the sensor may be linked by scanning the OMRD and storing the related data in the sensor. In some embodiments, the data acquired via the sensor may be linked with the OMRD by, for example, encoding the acquired data based on the data represented by the OMRD. The patient ID tag may then be utilized to identify the patient and confirm that the sensor, and/or historical data in the sensor or central computer system correspond to the proper patient. For example, in order to access a particular patient's historical data, it may be necessary to scan the OMRD with an optical reader. Thus, unless the patient has the patient ID tag that has been linked to the sensor and/or the patient-specific historical data, it will not be accessible. This may avoid issues relating to accessing inaccurate information for a particular patient. Indeed, the patient ID tag may be scanned to verify that the sensor attached to the patient was assigned to the patient, and, thus, confirm the data stored therein is correlated to the patient. Likewise, the patient ID tag may be read to verify correspondence to data stored on a central system that has been encoded based on the OMRD. Additionally, the link between the patient ID tag and the sensor may also present a substantial obstacle to improper remanufacturing of the sensor because, as will be discussed in further detail below, unless the proper OMRD is scanned, the sensor may not function.
FIG. 1 is a perspective view of a patient physiological data measurement system in accordance with an exemplary embodiment of the present disclosure. Specifically, FIG. 1 includes a pulse oximeter system, which is generally indicated by reference numeral 10. The system 10 includes a specially programmed computer or monitor 12 (e.g., a pulse oximeter) that communicatively couples via a cable or wirelessly to a sensor 14. The sensor 14 includes a sensor cable 16, a connector plug 18, and a body 20 configured to attach to a patient. In the illustrated embodiment, the body 20 of the sensor 14 is generally planar and configured for application to a patient's skin.
In accordance with present embodiments, the body 20 of the sensor 14 may be configured to couple with a patient's earlobe, finger, foot, forehead, or other locations on the patient that facilitate non-invasive measurement of desired physiological data (e.g., pulse rate and/or blood oxygen saturation). In another embodiment, the sensor 14 may be configured for invasive operation and the body 20 may be configured for insertion into a patient. The sensor cable 16 and connector plug 18 may enable electronic communication from the sensor 14 to the monitor 12, and facilitate coupling and/or decoupling the sensor 14 from the monitor 12. In some embodiments, the sensor 14 may couple directly to the monitor 12 via the sensor cable 16. In other embodiments, the sensor 14 may communicate with the monitor 12 wirelessly (e.g., via radio waves) and may not include the cable 16 or the connector plug 18.
The sensor 14 may cooperate with a patient ID tag in accordance with present embodiments. An OMRD 22 may be included on the patient ID tag, which may be associated with the sensor 14. The patient ID tag may be integral with or separate from the sensor 14. For example, as illustrated in FIG. 1, the patient ID tag may include a patient armband 24. However, in other embodiments, the patient ID tag may be a component of the sensor 14 that attaches and remains attached to a patient, such as a bandage portion of the sensor 14. In some embodiments, the OMRD 22 may include barcode, as illustrated in FIG. 1. In other embodiments, the OMRD 22 may include machine-readable graphic features and/or text, as illustrated by the armband 24 depicted in FIG. 2. Indeed, the OMRD 22 may include or be incorporated into a trademarked symbol or word such that potential remanufacturing entities could not reproduce the OMRD 22 without potentially violating trademark laws. The OMRD 22 may be printed, etched, included on a label that is attached via adhesive, and so forth. In the embodiment illustrated by FIG. 1, the OMRD 22 is positioned on a portion (e.g., an outward facing portion) of the armband 24 that is accessible when attached to a patient 26. As will be discussed in further detail below, the OMRD 22 may be utilized in conjunction with an information element 28 of the sensor 14 to link data to the patient 26 and prevent unauthorized remanufacture of the sensor 14 in accordance with present embodiments. In the embodiment illustrated by FIG. 1, the information element 28 is disposed within the sensor body 20. However, in other embodiments, the information element 20 may be attached to an outer portion of the sensor body 20, disposed within the sensor cable 16, disposed within the connector plug 18, or included in some other fashion.
The OMRD 22 may be read with an optical reader 32, such as a barcode scanner. In other words, the optical reader 32 may translate the OMRD 22 into electronic data. In some embodiments, the optical reader 32 may be integral with a main body of the monitor 12, as illustrated in FIG. 1. In such embodiments, to scan the OMRD 22, the portion of the patient ID tag including the OMRD 22 may be passed in front of the optical reader 32. Thus, the optical reader 32 may read and convert the OMRD 22 into data that can be communicated to a memory of the monitor 12 and so forth. However, in some embodiments, as illustrated in FIG. 3, the optical reader 32 (e.g., a scanning gun) may be coupled to the monitor 12 via a reader cable 34. The reader cable 34 may be sufficiently long to facilitate scanning the OMRD 22 in various locations relative to the monitor 12. For example, the OMRD 22 may be printed on the armband 24 attached to the patient 26 such that it is accessible but such that it would be difficult to move the armband 24 in front of the optical reader 32. Thus, it may be desirable for the reader cable 34 to be long enough to facilitate movement of the optical reader 32 over the armband 24 instead of having to move the armband 24, and, thus, the patient 26, to the optical reader 32. In fact, in some embodiments, the optical reader 32 may wirelessly communicate with the monitor 12 to facilitate reading the OMRD 22 on the armband 24 without moving the armband 24 to the monitor 12. This may encourage attachment of the armband 24 to the patient prior to scanning. Additionally, while the embodiment illustrated in FIG. 3 shows the optical reader 32 coupled directly to the monitor 12, in other embodiments, the optical reader 32 may be coupled to the monitor 12 via the sensor cable 16. Furthermore, in some embodiments, the optical reader 32 may not communicate with the monitor 12, but, rather, the optical reader 32 may communicate directly with the sensor 14 or the information element 28. In fact, a small scanning mechanism or the like may be incorporated into sensor 14 to operate as the optical reader 32 in accordance with present embodiments.
With regard to linking patient-specific data to a patient, present embodiments may be capable of reading the OMRD 22 on a patient ID tag, such as the armband 24, with the optical reader 32 and utilizing a processor and a memory to electronically associate the data represented by the OMRD 22 with data stored within and/or acquired by the sensor 14. For example, present embodiments may include a laser scanner as the optical reader 32, a barcode as the OMRD 22, a patient ID bracelet as the armband 24, and a sensor memory as the information element 28. The laser scanner may be configured to read the barcode disposed on the patient ID bracelet, and store the data represented by the barcode, which may be referred to as barcode data, on the sensor memory. Thus, the ID bracelet and the sensor may be linked by the stored barcode data on the sensor memory. The sensor memory may also store historical patient data acquired by the sensor. Thus, the historical patient data and the barcode data may be associated by common storage. In accordance with present embodiments, storing the barcode data on the same memory with the historical patient data may include electronically linking the barcode data with the patient data. For example, the patient data may be encoded based on the barcode data such that it cannot be accessed without periodically entering the barcode data by rescanning the barcode when certain predefined conditions are present, such as each time the sensor is activated. Accordingly, the sensor and the stored data may be specifically linked to the patient ID bracelet, and, thus, linked to the patient on whom the patient ID bracelet has been placed. In other embodiments, other memory devices may be employed in addition to or instead of the sensor memory. For example, a central system memory or a pulse oximeter memory may be utilized to store patient specific data that is encoded based on the barcode data. Subsequent access to the centrally stored data may require entry of the barcode data by scanning the barcode on the patient ID bracelet. Regardless of the location of the memory, such subsequently scanned data may be required to match the initially scanned data or data that was provided at manufacture to access the historical data or to even function with the memory device.
Also, as indicated above, the functional component 28 and the OMRD 22 may cooperate to prevent efficient remanufacture of the sensor 14. For example, in one embodiment, the functional component 28 includes a sensor memory and the OMRD 22 includes a barcode, and, in operation, the sensor memory may prevent the sensor 14 from functioning to acquire or supply data unless a particular barcode is scanned by the optical reader 32, such as a barcode scanner. Further, the barcode may be printed on the patient ID tag, which may include a sensor component (e.g., a sensor bandage), and the barcode may be destroyed after a single use of the patient ID tag. Indeed, the patient ID tag may be destroyed or disassociated with the sensor 14 after a single use due to the location of the barcode, the material used to print the barcode, and so forth. For example, the patient ID tag may include a barcode printed in ink that fades due to exposure. As another example, the sensor may simply be disassociated with the patient after use because the barcode that the sensor is configured to be activated with remains with the patient after use and the sensor does not. Specifically, for example, the barcode may be printed on a portion of the sensor 14 that couples with the patient and tears away from the sensor 14 when removed, or printed on a patient ID bracelet that is discarded after use. Thus, remanufacturing the sensor 14 may be exceedingly difficult because the sensor 14 may be designed not to work without receiving the barcode data, which is generally unique to the sensor 14, and the barcode data may be encoded in the printed barcode that is typically destroyed or removed after a single use of the sensor 14.
It should be noted that, in accordance with present embodiments, a sensor may include various types of OMRD, such as barcode, machine-readable patterns, machine-readable text, and so forth. Further, the OMRD may be printed in ink that fades or that is not visible to the human eye, printed on patient ID tags that are designed to tear apart upon removal, or otherwise printed in such a manner as to make later access to the OMRD difficult or impossible. Thus, remanufacture of the sensor may be substantially prevented. For example, as indicated above, the sensor may include an information element disposed therein to facilitate measurement and ensure quality control. This information element may be configured to prevent the sensor from functioning unless the data from a specifically assigned OMRD is received by the information element. Because the OMRD may be specific to the information element, remanufacture of the sensor becomes difficult. Indeed, in order to remanufacture the sensor, the OMRD would have to be reproduced, which may be economically inefficient for potential remanufacturing entities. Furthermore, a potential remanufacture of the sensor may include added difficulty because the OMRD may be substantially destroyed or separated from functional components of the sensor after a single use of the sensor.
FIG. 4 illustrates a front portion 42 and a back portion 44 of a sensor 40 in accordance with present embodiments. The sensor 40 may be configured for permanent attachment to the patient while the patient is being treated, like a patient ID bracelet. Thus, an OMRD 46 on the sensor 40 may be utilized to link historical patient data stored in the sensor 40 or elsewhere to the patient to whom the sensor 40 is affixed. In other embodiments, a barcode or some other OMRD may be positioned on some other portion of the sensor or even separate from the sensor. For example, the OMRD 46 may be printed on a tag 46 attached to the sensor 40 or attached to a sensor cable, as illustrated in FIG. 5. In another embodiment, the OMRD 46 may be printed directly on a sensor cable, as illustrated in FIG. 6.
Specifically, in the illustrated embodiment of FIG. 4, the sensor 40 is a pulse oximeter sensor that includes a pair of emitters 48 (e.g., a red emitter and an infrared emitter) configured to emit light waves, and a photodiode detector 50 that is arranged to detect the emitted light waves. Such sensors are typically configured to attach to a patient's finger, foot, forehead, or earlobe to facilitate measurement of blood characteristics in the associated tissue. For example, the sensor 40 may be adapted to project light from the emitters 48 through the outer tissue of a finger and into the blood vessels and capillaries inside, and detect the emitted light at the detector 50 as the light emerges from the outer tissue of the finger. In operation, the detector 50 may generate a signal based on the detected light and provide the signal to the monitor 12, which may determine blood oxygen saturation based on the signal. For example, the monitor 12 may utilize the signal to display a plethysmographic waveform. Data such as this may be stored in a sensor memory 52, a central system memory, or the like. Further, such data may be linked to the OMRD 46 by requiring that the OMRD 46 be read by an optical reader prior to granting access to the stored data. Indeed, the patient data may even be encoded based on the OMRD 46 such that the data represented by the OMRD 46 is required to decipher the patient data.
In some embodiments the sensor 40 may function as both a sensing mechanism and a patient ID tag. The front portion 42 of the sensor 40 is configured for placement adjacent a patient. Thus, the back portion 44 of the sensor 40 faces away from the patient when the sensor 40 is properly attached to a patient. Accordingly, the back portion 44 remains accessible to the optical reader 32 during use and includes the OMRD 46 in accordance with present embodiments. Specifically, in the illustrated embodiment, the sensor 40 includes a barcode printed on the back portion 44. In other embodiments, the barcode or some other OMRD may be positioned on some other portion of the sensor or even separate from the sensor. For example, as generally illustrated by FIG. 1, the barcode may be printed on a separate item that can be attached to a patient, such as a patient armband, a patient ID bracelet, a sticker, or the like.
Further, as discussed above, the sensor 40 may include the sensor memory 52, which may be internal or external to the sensor 40, and which is configured to store data. For example, the sensor memory 52 may store historical patient data, trend data, and/or data that relates to disabling or enabling the functionality of the sensor 40. In one embodiment, the sensor memory 52 may include a memory device (e.g., ROM) that stores data corresponding to data indicated by the OMRD 46 disposed on the sensor 40. A correlation between the data of the OMRD 46 and the data stored on the sensor memory 52 may be required for the sensor 40 to function. For example, a processor in the monitor 12 or the sensor 40 may compare the data stored in the sensor memory 52 with the data identified by scanning the OMRD 46 and determine whether the data matches. If the data does not match, the sensor 40 and/or the monitor 12 may prevent operation of the sensor 40 and/or provide an error indication (e.g., an alarm). In other embodiments, a combination of the data retrieved from the OMRD 46 and the data stored in the information element 52 may be required to enable functionality. For example, the OMRD 46 may include data that points to a storage location in the sensor memory 52 for comparison.
Various techniques may be utilized to prevent copying and/or erasing the sensor memory 52 for reuse. For example, to prevent copying of data from the sensor memory 52, the data corresponding to the data represented by the OMRD 46 may be scattered in different memory locations. Thus, a correspondence between the data of the OMRD 46 and the data in the sensor memory 52 may be difficult to discern. Further, encryption of the data may be employed. In one embodiment, an encryption feature, such as an encrypted signature, may be included on the sensor memory 52. Accordingly, if the sensor memory 52 is erased in an attempt to remanufacture the sensor 40, the encryption feature will also be erased, which will prevent further use of the sensor 40 by monitors that require such an encryption feature.
With regard to the data encoded by the OMRD 46, the OMRD 46 may encode data that can be used to identify the patient. For example, upon checking into a hospital, a patient may be assigned an OMRD 46 that is linked to the patient. In other words, the patient may be electronically associated with a specific OMRD 46. Thus, each time the OMRD 46 is read by an optical reader, the association with patient may be recognized. In some embodiments, the OMRD 46 may be specifically derived based on the patient information. For example, an OMRD 46 may be printed for a patient such that it encodes certain patient information. Additionally, other information may be encoded by the OMRD 46, such as the name or the type of a particular sensor. The OMRD 46 may also be used to store a unique serial number for a particular sensor or a unique code which is assigned to each customer. In another instance, the OMRD 46 may be used to store information directly required for sensor operation, such as a single piece of calibration data that the monitor 12 can read and use to interpret remaining encrypted data stored in the information element 52. The single piece of calibration data may employ the same encryption scheme as that used to store the remainder of the calibration data in the sensor memory 52. In some embodiments, the OMRD 46 may contain information required to decrypt the information stored in the sensor memory 52. For example, patient-specific data may be inaccessible without access to the information contained in the OMRD 46, and periodic scanning of the OMRD 46 may be required. Thus, the specific patient data may be electronically tied to the patient to whom the OMRD 46 is affixed via an armband, patient ID bracelet, or the like. Further, the encryption scheme may vary from one sensor to another. This would require a potential remanufacturing entity to obtain and print a unique OMRD 46 for each sensor that is remanufactured.
Accordingly, in order for the sensor 40 and/or the monitor 12 to function such that patient data may be newly acquired and/or accessed from storage, the data stored in the information element 52 must cooperate with or correspond to the data translated from the OMRD 46 by scanning the OMRD 46 with the optical reader 32. As a specific example, the sensor memory 52 may include a flash memory that stores an encrypted string of numbers that should correspond to the numbers represented by the OMRD 46 printed on a bandage portion of the sensor 40. Thus, when the OMRD 46 is scanned by the optical reader 32, the encrypted data in the memory 52 may be compared to the data obtained from the optical scan, and, if the data does not match, the sensor 40 and/or the monitor 12 may not function. This may prevent unauthorized remanufacture of the sensor 40 because it would be difficult to perform bulk remanufacturing operations. Indeed, each sensor would have to be specifically remanufactured to include the appropriate OMRD. Further, the OMRD 46 may be difficult to retrieve after use of the sensor 40 because it may be destroyed or separated from the sensor 40.
It should be noted that, in some embodiments, the information element 52 may be manufactured with a blank portion for storing the data represented by the OMRD 46. Thus, the sensor 40 may essentially be generic relative to the OMRD 46 until the OMRD 46 is initially scanned and the associated data is communicated and stored in the information element 52. For example, in use, a unique OMRD 46, such as a unique barcode, may be scanned by the optical reader 32. Upon scanning the barcode 46, the associated data may be stored in the memory 52 and the sensor 40 may be enabled to operate. Additionally, any data acquired by the sensor 40 may be designated as being associated with the OMRD 46 to facilitate association of the data with the patient and/or prevent access to the data without confirming the identify of the patient by scanning the OMRD 46. In some embodiments, scanning any manner of data will not necessarily enable operation. Rather, it may be necessary for the data to have a certain format or include certain basic information. Thus, once the proper type of data has been scanned into the memory 52, the sensor 40 may be enabled to operate. However, subsequent operation (e.g., operation after the sensor 40 has been powered down or detached from the monitor 12) may be prevented unless an identical OMRD value is scanned and communicated to the memory 52. Accordingly, the sensor 40 may be originally manufactured such that it can be electronically coupled with any barcode having the proper type of encoded data by storing that data on the sensor 40. However, reuse of the sensor 40 is prevented unless an OMRD identical to that initially scanned into the memory 52 is reproduced and utilized to activate the sensor 40 for subsequent uses.
As a specific example of an operational procedure in accordance with present embodiments, when a sensor is connected to a monitor, the monitor may recognize the connection to the sensor and prompt a user to scan a barcode with an optical scanner. Further, a memory field in a memory device of the sensor may be read because the memory field is intended to store barcode data. If no barcode data is present in the memory field, data retrieved from the scanned barcode may be written to the memory field. Indeed, the data retrieved from the scanned barcode may be transmitted from the monitor or transmitted directly from the scanner to the sensor memory for storage in the memory field. The barcode data, which is specifically assigned to the sensor, may be used to tag or identify data acquired by the sensor as belonging to that particular sensor. When data is initially stored in the memory field, the sensor may begin to function, or a second scan of the barcode on the sensor may be required to confirm a correspondence between the data stored in the sensor and the data represented by the barcode when certain conditions are present. Alternatively, if data, such as a unique serial number, is present in the memory field when the sensor is initially connected, the stored data may be compared to the barcode data obtained from the barcode via the optical scanner. If the data stored in the sensor memory corresponds to that obtained from the barcode, the sensor may be allowed to operate. If it is different, the monitor may reject the sensor and/or indicate that the sensor is not an approved sensor.
In one embodiment, an OMRD associated with a sensor may store data that is required for sensor operation. For example, a barcode printed on a sensor bandage or patient armband may include calibration data, data required to decrypt information provided by the sensor, data that combines with data stored in a sensor memory to enable cooperation with a monitor, and so forth. Thus, the appropriate OMRD (e.g., barcode) is required for proper sensor operation and/or access to historical data, and an error in printing a new OMRD would prevent further use of the sensor and/or access to the data. Further, because an OMRD is uniquely associated with a specific sensor, simply replicating a single OMRD for multiple sensors would only enable the associated sensor to be reused. For example, if a barcode is scanned to reveal data that does not match or correspond to the data in a memory of a particular sensor, the sensor will not work because a processor of the associated monitor or of the sensor itself will compare the data and recognize differences and/or attempt to utilize the data in combination and fail.
Various techniques, sensor components, and packaging procedures may be utilized to further prevent remanufacture of sensors in accordance with present embodiments. Indeed, sensors and/or related components (e.g., patient ID tags) may be manufactured or packaged such that there is a high likelihood that an OMRD provided with the sensor will be destroyed, become unreadable, or disassociated from functional features of the sensor (e.g., an information element) after a single use of the sensor. For example, as illustrated in FIG. 7, a sensor 60 may be provided with an OMRD 62 disposed on an outer layer 64 of the sensor 60. The outer layer 64 may be attached to a main body 66 of the sensor 60 with a very light adhesive, while the main body 66 includes a more substantial adhesive on a functional side 68 of the sensor 60 for attaching to a patient. Thus, the functional side 68 of the sensor 60 may be coupled to a patient, leaving the OMRD 62 exposed, and, when the sensor 60 is removed, the outer layer 64 will likely become dislodged from the sensor 60, as illustrated by the arrow 70 in FIG. 7. Further, the outer layer 64 may be made of material that will not hold up to sterilization procedures. For example, exposure of the outer layer 64 to certain types of radiation or materials used in sterilization may cause the outer layer 64 to dissolve or discolor such that the OMRD 62 becomes unreadable.
In another embodiment, as illustrated by FIG. 8A, the sensor 60 may be provided with an expansive bandage 72 that completely covers and expands beyond the perimeter of the main body 66 of the sensor 60 such that it facilitates attachment of the sensor 60 to a patient. The OMRD 62 may be printed on the bandage 72. Because the bandage 72 completely covers the main body 66, removal of the sensor 60 may be achieved by first removing the bandage 62 from a patient 64, as illustrated in FIG. 8B. Thus, after a single use, the OMRD 62 printed on the bandage 72 may be separated from the functional features of the sensor 60, which will limit the ability to reproduce the OMRD 62 on a remanufactured sensor. To encourage removal of the bandage 72 in a manner that separates it from the main body 66, a tab 76 may be provided to facilitate removal. For example, the tab 76 may be an extension of the bandage 72 that does not include adhesive, and, thus, is easy for a clinician to grab and pull away from the patient 74. Additionally, specific instructions for use may be provided that indicate a user should peel off the bandage 72 and discard it during removal to protect against contributing to the remanufacture of sensors that may malfunction. Further, the bandage 72 may be loosely attached to the main body 66, and or the main body 66 may include an adhesive for attaching to the patient 74 to encourage separation of the bandage 72 from the main body 66 during detachment of the sensor from the patient 74.
FIG. 9 illustrates yet another embodiment that may encourage separation of the OMRD 62 from the functional features of the sensor 60 after a first use of the sensor 60. Specifically, the sensor 60 and a separate label 82 may be lightly adhered to a base sheet 84, which is illustrated as a clear sheet of plastic, and both the sensor 60 and the label 82 may include adhesive material for attaching to a patient. For example, with regard to the embodiment illustrated by FIG. 9, the sensor 60 and the label 82 may be attached to a patient's forehead by exposing adhesive on the sensor 60 and the label 82 opposite the base sheet 84, pressing the sensor 60 and the label 82 against the patient's forehead through the base sheet 84, and then peeling the base sheet 84 away. Thus, the sensor 60 and the label 82, which includes the OMRD 62, are separately attached to the patient, and will likely be disassociated after a single use. A similar result may be obtained by providing the sensor 60 with an arm band 92 that is initially attached and that may be separated and attached to the patient 74, as illustrated in FIG. 10. The arm band 92 includes the OMRD 62. Because the arm band 92 may be removed and attached to the patient, the OMRD 62 will likely be discarded separate from the functional features of the sensor 60 after the first use of the sensor 60.
FIG. 11 illustrates another embodiment that facilitates disassociation of the OMRD 62 from functional components of the sensor 60 after a single use. Specifically, FIG. 11 includes the sensor 60 with a bandage component 102 for attachment of the sensor 60 to a patient, wherein the bandage component 102 includes a tear-away portion 104 that is separated from a main portion 106 of the bandage component 102 by perforations 108. The tear-away portion 104 includes the OMRD 62 printed thereon. Accordingly, when the sensor is removed 60, the perforations 108 will encourage tearing and separation of the OMRD 62 from the functional features of the sensor 60. In some embodiments, the perforations 108 may be positioned such that the OMRD 62 itself becomes mangled and unreadable. For example, the perforations 108 may combine to for a jagged line along the OMRD 62.
In some embodiments, the OMRD 62 may be printed on the sensor 60, on a sensor cable, or on a tag associated with the sensor 60 with a medium that reacts in some manner to exposure to air, sterilization, and so forth, or that makes access to information difficult. For example, applying the sensor 60 may expose the ink used to make the OMRD 62 to air or to the patient's skin, which may initiate a reaction that degrades the ink over time such that it can no longer be read. As another example, the OMRD 62 may be printed with an ink that is not substantially visible to the human eye or that reacts with a chemical or radiation typically used in sterilization techniques. For example, typical types of chemicals utilized in sterilization include alcohol, peroxide, and so forth. Examples of light waves utilized in sterilization may include gamma and/or electron-beam irradiation.
The ink or material utilized to form the OMRD 62 may include a chemical that essentially disappears, degrades, or becomes visible upon exposure to ethanol, steam, radiation, or the like. Specifically, as illustrated in FIG. 12, the OMRD 62 may include a barcode wherein certain bars are printed in an ink that is not initially visible, as represented by clear bars 112, while other bars are always visible, as represented by dark bars 114. When the clear bars 112 are exposed to sterilization chemicals and/or radiation, the clear bars 112 may become visible. In other embodiments, all or a portion of the bars 112, 114 may disappear when exposed in some manner to sterilization. Thus, such sterilization would prevent functionality as a remanufactured sensor because the OMRD 62 would be gone, unreadable, or include wrong information. In an embodiment wherein features are added to the OMRD 62 upon sterilization, such as adding visible bars to a barcode by making certain ink visible, a processing feature (e.g., a microprocessor in the sensor 60 or an oximeter) may be programmed to scramble all or some of the entries in an information element of the sensor when such extra bars are detected. In some embodiments, the clear bars 112 may represent bars printed in an ink that is not visible to the human eye but that is detectable by a scanner, which may cause confusion for potential remanufacturing entities.
Remanufacture of a sensor that was originally assembled in accordance with present embodiments may be achieved, but may be difficult. For example, a used sensor may be sterilized and reassembled to include the original or a copy of the OMRD associated with the sensor. Further, various components may be replaced and/or reused. In some embodiments, certain functional features, such as an information element, of the sensor may be included in a new or remanufactured sensor body and a copy of the OMRD may be provided on or with the remanufactured sensor. Reprocessing may include erasing all of the information on the information element (e.g., memory) of a sensor, which would also erase encrypted information required for operation. Once the information element is blank, new encryption information could be included with a blank OMRD code field (e.g., a field for storing data that should correspond to the data encoded by an OMRD associated with the sensor) by an entity with the proper encryption knowledge. In some embodiments, this may include wiping a memory and pointing to a new memory section for storing encryption data and/or OMRD) code.
It should be noted that the information element may include any of various different types of memory in accordance with present embodiments. For example, write-once memory (WOM) and/or rewritable memory (EPROM, EEPROM) may be utilized. These different types of memory would have an impact on attempts to remanufacture a sensor. With regard to write-once memory, for example, the write-once memory would be invalidated by any attempt to erase the biometric data code field because it cannot be rewritten. With regard to rewritable memory or write-many memory, the biometric data code field could be erased and rewritten. However, such a memory may be prevented from functioning in accordance with present embodiments because of encryption of the biometric data field, scattering of the biometric data field, and/or a special field indicating that the biometric data has been written (e.g., a recorded date of rewriting).
While the embodiments set forth in the present disclosure 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 disclosure is not intended to be limited to the particular forms disclosed. Indeed, the present techniques may not only be applied to measurements of blood oxygen saturation, but these techniques may also be utilized for the measurement and/or analysis of other physiological characteristics. The disclosure is to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims.

## Claims

1. A system for facilitating the monitoring of physiologic conditions, comprising:
an optical reader configured to translate an optical machine-readable representation of data associated with a patient into electronic data;
a memory device configured to receive and store the electronic data after an initial reading of the machine-readable representation of data by the optical reader; and
a processor configured to associate the electronic data with historical data obtained from the patient and limit access to the historical data based on whether the optical reader provides matching electronic data based on a subsequently read optical machine-readable representation of data when predefined conditions are met.

2. The system of claim 1, further comprising a patient identification tag, wherein the optical machine-readable representation of data is on the patient identification tag.

3. The system of claim 2, wherein the patient identification tag is configured to attach to the patient to associate the optical machine-readable representation of data with the patient.

4. The system of claim 3, wherein the patient identification tag comprises a sensor, and wherein the sensor comprises the memory device.

5. The system of claim 1, wherein the subsequently read optical machine-readable representation of data comprises the optical machine-readable representation of data.

6. The system of claim 1, wherein the predefined conditions comprise a condition wherein a sensor including the memory device is activated.

7. The system of claim 1, wherein the memory device comprises a memory component of a pulse oximetry sensor.

8. The system of claim 1, wherein the memory device comprises a memory component of a central computing system.

9. The system of claim 1, wherein the processor is configured to encode the historical data based on the electronic data such that access is limited to the historical data without the matching electronic data to decode the historical data.

10. The system of claim 1, wherein the processor is configured to prevent functioning with a sensor including the memory device based on whether the optical reader provides matching electronic data based on the subsequently read optical machine-readable representation of data when predefined conditions are met.

11. The system of claim 1, wherein the processor is a component of a pulse oximeter or a pulse oximetry sensor.

12. The system of claim 1, wherein the optical machine-readable representation of data is printed with a first material that is initially visible and a second material that is configured to become visible when exposed to air, sterilization chemicals, certain types of radiation utilized in sterilization, and/or skin.

13. The system of claim 1, wherein all or a portion of a material utilized to print the optical machine-readable representation of data is surrounded by material configured to become visible when exposed to radiation and/or chemicals associated with sterilization.

14. The system of claim 1, wherein the optical machine-readable representation of data comprises a barcode and/or a trademark.

15. A method, comprising:
converting an optical machine-readable representation of data assigned to a patient into electronic data with an optical reader;
storing the electronic data in a sensor memory of a sensor;
storing values for physiologic data acquired from the patient via the sensor in the sensor memory; and
limiting access to the physiologic data stored in the sensor memory with a processor by providing or prohibiting access to the physiologic data based on a comparison of electronic data subsequently read by the optical reader with the electronic data stored in the sensor memory.

16. The method of claim 15, comprising performing data manipulation with the processor to electronically link the electronic data to the physiologic data such that the electronic data subsequently read by the optical reader must match the electronic data to decode the physiologic data.

17. The method of claim 15, comprising transmitting the electronic data from the optical reader directly to the sensor memory for storage.