Abstract:
To make home patient care more successful, a machine may enable context aware physiological monitoring at home. For example, in one embodiment, the machine only allows the physiological monitor measurements to be made when the patient has proven that the patient has not undergone strenuous activity in a period preceding the measurement. That activity may skew the measurement and make the measurement unreliable. Without the machine information, the clinician may be unaware of the physical activity because the patient is not present in his or her office and could misdiagnose or misprescribe based on incorrect information.

Description:
BACKGROUND 
       [0001]    This relates to physiological monitoring. 
         [0002]    Physiological monitoring is the monitoring of a patient&#39;s physiological condition for purposes of medical diagnosis and/or treatment. Typically, a patient&#39;s blood pressure, pulse rate, pulse oximetry, and peak flow may be monitored. These measurements may be important to correct medical diagnosis and treatment. 
         [0003]    However, physiological monitoring by the patient, at home, is sometimes prone to errors. Some of these errors may be due to improper operation of the equipment and to improper procedures in association with that equipment. 
         [0004]    Because of the high cost of hospitalization, it is desirable to enable patients to stay at home and to treat them remotely, if possible. However, the ability to do so may be compromised where the physiological measurements are not sufficiently accurate. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is a schematic depiction of one embodiment of the present invention; 
           [0006]      FIG. 2  is a schematic depiction of the wearable kinematic sensor in accordance with one embodiment; and 
           [0007]      FIG. 3  is a flow chart for one embodiment. 
       
    
    
     DETAILED DESCRIPTION 
       [0008]    Some home-based physiological measurements, including blood pressure, pulse oximetry, and peak flow, may be recorded in a home environment. These measurements may then be transferred electronically to a clinician to monitor the patient&#39;s progress and to assess treatment options. In some cases, the context in which these measurements were taken is important in interpreting the readings. 
         [0009]    The clinician normally has no knowledge about what the patient was doing prior to taking the measurements, in the case where the measurements were transmitted by the patient from the patient&#39;s home over an electronic transport medium. If the patient walked upstairs, worked out, or did other activities prior to taking the physiological measurements, their accuracy may be questioned. The type of activity and the magnitude of the activity can have a significant impact on the physiological monitor&#39;s reading. Specifically, physical activity typically raises blood pressure. 
         [0010]    This missing contextual information can be provided by a body kinematic sensor that captures and logs physical activity. Then, when the physiological monitor data is transferred to the clinician, it may be accompanied with the kinematic information that enables the clinician to determine what the patient was doing at times proximate to the measurements in some embodiments. 
         [0011]    Thus, referring to  FIG. 1 , a home physiological monitoring system may include a wireless center  12  in one embodiment. In some cases, a wired center may be used as well. However, a wireless center may communicate wirelessly with physiological monitor  16 . Examples of physiological monitors include blood pressure cuffs, pulse oximetry devices, and peak flow measurement devices. 
         [0012]    The measurements taken by these devices may be transferred wirelessly or by a wired connection to the wireless center  12 . The wireless center  12  may also be in wireless communication with a wearable kinematic sensor  14 . The wireless communication may be short range wireless communication (such as a Bluetooth connection) or long range wireless communication (such as a cell phone connection), as desired. 
         [0013]    The wireless center  12  may include a processor or a control  28  and a storage  30 . The storage  30  may store a sequence of instructions  32  in some embodiments. In such case, the storage  30  may comprise a computer readable medium storing instructions for execution by the control  28 . A user interface  50  may be a display, a speaker, a microphone, a keyboard, or a mouse, to mention a few examples. A monitor interface  50  may process wired or wireless signals from the physiological monitors  16 . The sensor interface  48  processes signals from the sensor  14 . 
         [0014]    The wireless center  12  may be in communication over wired or wireless connections with a clinician. Thus, a patient may monitor his or her physiological conditions at home, enable these to be transferred to the wireless center, and then the wireless center  12  may transfer them over a suitable medium to the clinician. 
         [0015]    Referring to  FIG. 2 , the kinematic sensor  14  may include an accelerometer  26 , a temperature sensor  58 , a pulse meter  62 , a gyroscope  56 , and a moisture sensor  64 , coupled to a controller or processor  22 . The moisture sensor  64  may, for example, sense ambient air moisture for use in connection with peak flow readings. A storage  24  may enable storage, over a period of time, of the activity readings. The readings may be stored in association with a time from the timer  25 . 
         [0016]    Thus, a log may be made of what activities were done at what time in one embodiment. This log may then be combined with a log indicating the time when the physiological measurements were taken. The physiological monitoring log may be prepared by a timer equipped monitor  16 , or by the wireless center  12  logging the time when the measurement is received. It may be determined whether physical activity was undertaken in proximity to the physiological measurements. 
         [0017]    In one embodiment, the wearable kinematic sensor is a Shimmer wireless sensor platform from Shimmer Research, Dublin, Ireland. The Shimmer wireless sensor platform includes a low power microprocessor that controls device operation and facilitates communication with peripheral devices. It captures sensor data from analog-to-digital converter channels. It then periodically conveys this data over a wireless link to the wireless center  12 . In some cases, the device is relatively small and light and can be carried on the person&#39;s body or clothing. It includes a three axis microelectromechanical accelerometer for sensing movement. 
         [0018]    In one embodiment, the sensor  14  communicates over a Bluetooth wireless connection with the wireless center  12 . The wireless center processes the information it receives and coordinates the log of time and activity with the time when physiological monitor readings were received. The wireless center  12  then can combine all of this information and transmit it in a useful form to the clinician in some embodiments. 
         [0019]    In one embodiment, if no activity levels above a threshold were recorded over a predetermined measurement window, such as fifteen minutes prior to the physiological measurement; the physiological monitor&#39;s measurement can be transmitted to clinician. Otherwise, the patient may be asked to sit restfully for a period of time prior to taking the measurements again. 
         [0020]    The sensor  14  may provide patient activity information upon request over a preset time period, such as fifteen minutes. The information may be generated by an accelerometer  26  that, in one embodiment, may be a three axis accelerometer. In one embodiment, the activity information may be refined by determining the minimum and maximum accelerometer values over the predetermined time window. The average of those values may be determined and compared to a predetermined limit. These analyses can be done in the sensor  14  or the wireless center  12 . 
         [0021]    The limits may be determined by looking at average values for various activities such as walking, running, climbing stairs, etc. Thus, in some cases, the readings can be used to determine the activity type. The data may be better characterized, in some embodiments, using data from the gyroscope  56 . 
         [0022]    Referring to  FIG. 3 , a sequence, in accordance with one embodiment, is depicted. The sequence, in one embodiment, may be implemented by instructions stored on a computer readable medium such as the storage  30 . In other cases, the sequence may be implemented in hardware. 
         [0023]    Initially, at diamond  34 , the wearable kinematic sensor  34  is queried to determine whether or not there was a response to a ping for activity data, or not. This query may be in response to a user request to take a physiological monitor reading, in one embodiment. In some cases, the sensor may only provide information at certain intervals in order to save power. In other cases, the sensor only provides data upon request. 
         [0024]    If a response was received from the sensor  14 , the data may be downloaded and processed, as indicated at block  36 . Thus, a log of time and activity may be received for a preceding time period of interest, which may be fifteen minutes in one embodiment. That information may be processed to determine an average activity level and to compare that average activity level to a preset threshold level, in one embodiment. 
         [0025]    Thus, when queried, the sensor only sends the relevant data, i.e. the activity measurement for the preceding pertinent window, e.g. fifteen minutes in one embodiment. In such case, the wireless center  12  may only pull the data from the sensor  14  when it has received a request to use a physiological monitor reading. In that case, the sensor may be programmed only to provide activity information for a predetermined time, such as fifteen minutes of data, in response to a request from the wireless center  12 . 
         [0026]    The activity time or time window of activity level greater than the threshold is then checked in diamond  38 . If there was activity above a threshold within the time window when activity should be limited, a user message may be displayed with a wait time period, as indicated at block  40 . In such case, the user is asked to wait a preset time (e.g. fifteen minutes) before seeking to take the physiological measurements. 
         [0027]    If there was no activity in excess of the threshold within the activity time or time window, the user may be advised through the user interface to proceed to take the physiological monitor measurement. The physiological measurements may be collected from the physiological monitors, as determined in diamond  42 . If the information is successfully collected, it can be aggregated with the activity measurements if desired and transferred to a centralized data repository in blocks  44  and  46 . 
         [0028]    In some embodiments, three separate units may be used, including the wireless center, the body wearable sensor, and the physiological monitor or monitors. However, in other embodiments, less than three discrete units may be provided. For example, the physiological monitor may include the wireless center. In other embodiments, a wearable device may perform all of the functions of the physiological monitor, the wireless center, and the kinematic measurement. In other embodiments, more than three units may be used. 
         [0029]    In other embodiments, additional information may be collected by the wearable sensor  14 . For example, in addition to kinematic measurements, a wearable sensor may also provide information about body temperature, moisture or sweating, ambient moisture, pulse, etc, which may be useful in analyzing the physiological monitoring measurements or for other purposes. 
         [0030]    References throughout this specification to “one embodiment” or “an embodiment” mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one implementation encompassed within the present invention. Thus, appearances of the phrase “one embodiment” or “in an embodiment” are not necessarily referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be instituted in other suitable forms other than the particular embodiment illustrated and all such forms may be encompassed within the claims of the present application. 
         [0031]    While the present invention has been described with respect to a limited number of embodiments, those skilled in the art will appreciate numerous modifications and variations therefrom. It is intended that the appended claims cover all such modifications and variations as fall within the true spirit and scope of this present invention.