Abstract:
A user interface for a pulse oximetry device that calculates physiologic parameters of a subject including at least a subject&#39;s heart rate and S p O 2 , is disclosed wherein the interface comprises a graphical display of at least one raw data signal of the pulse oximetry device that maintains heart and breath rate components and a display of the calculated heart rate and S p O 2  of the subject. The interface may further include a user selectable data averaging function in which the interface is configured to selectively obtain and display averages of at least some of the calculated physiologic parameters over a defined period.

Description:
RELATED APPLICATIONS 
       [0001]    This application claims the benefit of U.S. Provisional patent application Ser. No. 60/884,392 filed Jan. 10, 2007 entitled “Small Animal Pulse Oximeter User Interface.” 
         [0002]    This application is a continuation in part of U.S. patent application Ser. No. 11/858,877 filed Sep. 20, 2007 entitled “Medical Display Devices for Deriving Cardiac and Breathing Parameters Derived from Extra-thoracic Blood Flow Measurements.” application Ser. No. 11/858,877 claims the benefit of provisional patent application Ser. No. 60/826,530 entitled “Medical Devices and Techniques for Deriving Cardiac and Breathing Parameters from Extra-thoracic Blood Flow Measurements and for Controlling Anesthesia Levels and Ventilation Levels in Subjects” filed Sep. 21, 2006. 
         [0003]    This application is a continuation in part of U.S. patent application Ser. No. 11/951,194 filed Dec. 5, 2007 entitled “Research Data Classification and Quality Control for Data from Non-Invasive Physiologic Sensors.” application Ser. No. 11/951,194 claims the benefit of U.S. Provisional patent application Ser. No. 60/868,681 filed Dec. 5, 2006 entitled “Research Data Quality Control Software.” application Ser. No. 11/951,194 claims the benefit of U.S. Provisional patent application Ser. No. 60/884,392 filed Jan. 10, 2007 entitled “Small Animal Pulse Oximeter User Interface.” 
     
    
     BACKGROUND OF THE INVENTION 
       [0004]    1. Field of the Invention 
         [0005]    The present invention relates to user interface for physiologic parameter sensors and more particularly to small animal pulse oximeter user interfaces. 
         [0006]    2. Background Information 
         [0007]    The present invention is related to the user interface provided in physiologic sensor devices, particularly those for use with non-invasive physiologic sensors, such as pulse oximeters, and in particular those used on small subjects in a research environment. 
         [0008]    As background, one type of non-invasive physiologic sensor is a pulse monitor, also called a photoplethysmograph, which typically incorporates an incandescent lamp or light emitting diode (LED) to trans-illuminate an area of the subject, e.g. an appendage, which contains a sufficient amount of blood. The light from the light source disperses throughout the appendage {which is broken down into non-arterial blood components, non-pulsatile arterial blood, and pulsatile blood}. A light detector, such as a photodiode, is placed on the opposite side of the appendage to record the received light. Due to the absorption of light by the appendage&#39;s tissues and blood, the intensity of light received by the photodiode is less than the intensity of light transmitted by the light source (e.g., LED). Of the light that is received, only a small portion (that effected by pulsatile arterial blood), usually only about two percent of the light received, behaves in a pulsatile fashion. The beating heart of the subject, and the breathing of the subject as discussed below, create this pulsatile behavior. The “pulsatile portion light” is the signal of interest, and effectively forms the photoplethysmograph. The absorption described above can be conceptualized as AC and DC components. The arterial vessels change in size with the beating of the heart and the breathing of the patient. The change in arterial vessel size causes the path length of light to change from d min  to d max . This change in path length produces the AC signal on the photo-detector, which spans the intensity range, I L  to I H . The AC Signal is, therefore, also known as the photoplethysmograph. 
         [0009]    The absorption of certain wavelengths of light is also related to oxygen saturation levels of the hemoglobin in the blood transfusing the illuminated tissue. In a similar manner to the pulse monitoring, the variation in the light absorption caused by the change in oxygen saturation of the blood allows for the sensors to provide a direct measurement of arterial oxygen saturation, and when used in this context, the devices are known as oximeters. The use of such sensors for both pulse monitoring and oxygenation monitoring is known, and in such typical uses, the devices are often referred to as pulse oximeters. These devices are well known for use in humans and large mammals and are described in U.S. Pat. Nos. 4,621,643; 4,700,708 and 4,830,014, which are incorporated herein by reference. 
         [0010]    Current commercial pulse oximeters do not have the capability to measure breath rate or other breathing-related parameters other than blood oxygenation. An indirect (i.e. not positioned within the airway or air-stream of the subject), non-invasive method for measuring breath rate is with impedance belts. Further, prior to the implementation of the MouseOX™ brand pulse oximeter, introduced in mid-December 2005, there were no commercial pulse oximeters that were effective for small mammals such as mice and rats. 
         [0011]    These existing physiologic sensor devices, particularly those for use with small subjects in a research environment, need a user interface to display results to the user and to further allow the user to effectively utilize the sensor devices. In general, many existing sensor device merely have a display to display current readings to the user, and the only functional system controls are the on/off controls. This limited user interface restricts the uses for the sensor device, particularly in a research environment. 
         [0012]    It is an object of the present invention to minimize the drawbacks of the existing technology and to provide a simple easy to use small animal physiologic sensor user interface. 
       SUMMARY OF THE INVENTION 
       [0013]    The present invention is directed toward the user interface for a physiologic parameter sensor that calculates physiologic parameters of a subject, such as a pulse oximeter. The details of the pulse oximeter, per se, and other physiologic parameter sensors (blood pressure monitors, eeg, ekg etc) are known in the art and not discussed herein in detail. The present invention is directed to the interface that allows the user, particularly a researcher, to more efficiently and effectively implement these sensor tools. 
         [0014]    One non-limiting embodiment of the present invention provides a user interface for a pulse oximetry device that calculates physiologic parameters of a subject including at least a subject&#39;s heart rate and S p O 2 , wherein the interface comprises a graphical display of at least one raw data signal of the pulse oximetry device that maintains heart and breath rate components and a display of the calculated heart rate and S p O 2  of the subject. The phrase “raw data signal” with regards to pulse oximetry devices will mean, within this application, a signal that maintains the heart and breath components of the signal together. The “raw” signal will typically undergo some signal processing (also called pre-processing such as analog filters and gains), but such processing is minimal and this signal is therefore considered raw within this application. This raw signal exhibits a much faster real time response than do the processed breath and heart rate signals. 
         [0015]    The pulse oximeter user interface of the present invention may further include a graphical display of a plurality of the calculated physiologic parameters over time, and a numerical display of a plurality of the calculated physiologic parameters at selected times, such as at the most recent calculation and/or at a user designated time. 
         [0016]    The pulse oximeter user interface of the present invention further includes a recording of the calculated physiologic parameters and an event file marker function which is configured to be user selected to physically identify selected time locations of the record. The file marker function may physically identify the selected times on an associated graphical display of the calculated physiologic parameters and may further mark a location of a recorded session. 
         [0017]    One non-limiting embodiment of the present invention provides a user interface for a physiologic parameter sensor that calculates physiologic parameters of a subject, wherein the interface comprises a user selectable data averaging function in which the interface is configured to selectively obtain and display averages of at least some of the calculated physiologic parameters over a defined period. 
         [0018]    The physiologic parameter sensor user interface of the present invention may provide that the data averaging further includes a user selection of the defined average period. The data averaging may be configured to ignore calculated physiologic values that are deemed unacceptable in the calculation of the averages. The data averaging may be configured to display intermediate average values during calculation and to display final average values to the user in a distinct manner from the display of the intermediate average values. The interface may be configured to selectively begin the defined period at any time designated by the use. The interface may be configured to operate on recorded or real time data. 
         [0019]    These and other advantages of the present invention will be clarified in the description of the preferred embodiments taken together with the attached figures in which like reference numerals represent like elements throughout. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0020]      FIG. 1  is a representative illustration of a summary data screen for a pulse oximeter user interface according to one embodiment of the present invention; 
           [0021]      FIG. 2  is a representative illustration of a more detailed summary data screen for the pulse oximeter user interface of  FIG. 1 ; 
           [0022]      FIG. 3  is another representative illustration of the summary data screen of  FIG. 2 ; 
           [0023]      FIG. 4  is a representative illustration of a main data collection screen for the pulse oximeter user interface of  FIG. 1 ; 
           [0024]      FIG. 5  is another representative illustration of the main data collection screen of  FIG. 4 ; and 
           [0025]      FIG. 6  is another representative illustration of user selectable data averaging diagnostic screen for the pulse oximeter user interface of  FIG. 1 . 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0026]    The present invention is directed to the user interface of a physiologic sensor device, such as a pulse oximeter device, particularly a physiologic sensor device for small mammals, such as found in many research applications. In such devices the output, generally including a display of the sensed parameter as determined by the sensor device, is displayed to the user in some format on an associated display device. The details of the physiologic sensor device are known in the art and are not included herein. The present invention has been implemented as a user interface on the MouseOX™ brand pulse oximeter for small animals, such as rats and mice. The invention can be implemented on other brands of pulse oximeters and other physiologic sensors. The advantages of the present invention are most notable in a research environment, but the invention is not limited thereto. Similarly, much research is done on animals, and the largest majority of animal research is performed with mice and rats. The present invention is clearly well suited for such animal research applications, but it is not limited to use with animal related sensors. 
         [0027]    Pulse Pleth Window 
         [0028]    The first aspect of the present invention is shown on a summary screen  10  of the interface of the present invention shown in  FIG. 1 . The summary screen includes a window  12  referenced as the Pulse Pleth window  12 . The window  12  appears on the pulse oximeter summary screen  10 , the detailed summary screen  40  (described below) and the main data collection screen  50  (described below) in the Mouse OX™ device sold by Starr Life Sciences, and provides a near real-time graphical display of the transmitted red and infrared pulse oximeter light intensities  14  as received by the receiver, to the user. In the manifestation as shown in the figure, the display  12  appears as dual oscilloscope traces  14 . A red trace  14  represents the red transmitted light intensity, while a yellow trace  14  represents the infrared transmitted light intensity. The transmitted light data that form these traces  14  are received in packets from the A/D card buffer and are transmitted across the USB cable to the computer. Once in the computer, they are processed in various ways and sent to the Pulse Pleth window  12  for graphical display. The Pulse Pleth window  12  as it appears in the MouseOX™ Summary screen  10  is what is shown in  FIG. 1 . 
         [0029]    One important utility of this graphical representation in window  12  of what is effectively raw data is that it allows the user to see the waveforms  14  so that their quality can be judged. Since the quality of the waveforms  14  determines the ability of the pulse oximeter to make continuous accurate measurements of its parameters, displaying the “raw signal” traces  14  to the user can allow him to be able to move/adjust the sensor location in order to improve signal quality. The raw data traces  14  are sufficient feedback for the user to perceive weaker and stronger signals based upon sensor location (within what ever adjustment is provided in a particular sensor mount). 
         [0030]    Note that the particular color of the traces  14  is inconsequential, and that the data does not have to be delayed or processed in order to provide beneficial information to the user. Additionally, the processing could be conducted in the same device that has the A/D board and/or the display screen. 
         [0031]    Summary Screen 
         [0032]    The remaining elements of the summary screen  10  should be discussed for a fuller understanding of the interface of the present invention. The summary screen  10  includes a numerical display of the physiologic parameters measured by the MouseOX™ pulse oximeter. These include a numerical display of the latest pulse distension measurement  20  with associated heading; a numerical display of the latest breath distension measurement  22  with associated heading; a numerical display of the latest heart rate measurement  24  with associated heading; a numerical display of the latest S p O 2  (oxygen saturation) measurement  26  with associated heading; and a numerical display of the latest breath rate measurement  28  with associated heading. 
         [0033]    The summary screen  10  further includes a control button  30  that will mark the data file as will be described in further detail below as it is an important aspect of the interface of the present invention. The summary screen  10  includes a file marker number  32  to indicate to the user which file marker has been set. 
         [0034]    The summary screen  10  further includes a status indicator  34  to identify if the system is recording, or playing back a recorded session or idle. Other status indicators can be added as desired. The summary screen  10  can include a variety of other control buttons  36  to perform other designated tasks such as pulling up windows, closing windows, and other interface that is necessary to better implement the oximeter. 
         [0035]    Parameter Color Change 
         [0036]    An improvement in data error indication involves letting the user know about problems with the data while the data is being collected. Although the quality of data can be assessed in a general sense using the Pulse Pleth window  12  described above, data signals from the Pulse Pleth window  12  that are judged to be of sufficient quality, may still result in the inability for the software algorithms to successfully calculate one or more parameters at a given instant of time. An additional aid to the user has been provided by changing the color of a given parameter in the data text boxes  20 - 28  each time calculation of the associated parameter in the given text box  20 - 28  does not pass the acceptance criterion for that parameter. An error flag may be thrown in a log file such cases that allow the user to flag data that is questionable at a later review. Additionally here an indication of a problem  16  is given on the window  12  and possibly on the main user screen while data are being collected. This feedback may be done in two ways. The first is that the background of the Pulse Pleth screen or window  12  changes color from black to green (and note that the color choices are arbitrary) while an error flag is active. Secondly, the numerical values displayed in the data text boxes  20 - 28  change color, including a color that matches the background of the text box such that the number is not seen, when a given parameter does not pass the acceptance criterion for that parameter. This display utility could be further improved by changing the background color on a given data display plot associated with a given error flag at a given time. 
         [0037]    Shown in  FIG. 2  a pictorial representation of the detailed summary display  40  of the user interface in normal operation, and  FIG. 3  is a representation of the display  40  of the user interface in operation while an error flag  16  is present. Obviously, these are not the same data sets, but serve to illustrate the two different cases. Note that not only the color change in the Pulse Pleth window  12 , but also the “graying out” of the Chart Data  22 ,  26  and  28  (also a color change) for the affected parameters only. Other parameters  20  and  24  are still considered to be valid. 
         [0038]    The detailed summary display or window  40  includes the parameter displays  20 - 28  for the most current data sets under the chart data heading  44 . Further the summary window  4  includes a display of the parameters  20 - 28  at a user selected location, such as at a file marker, under the heading curser data  46 . In light of the two sets of data values  20 - 28  that may be displayed in window  40 , a time indicator  42  is included above each column to convey the associated event time that each column is reflecting. 
         [0039]    Quick Diagnostic Measurement: Graphical Display of Parameters Over Time 
         [0040]    The following concepts deal with improving the ability of a device user to monitor the status of the animal, as well as the progress of a given experiment. The first item is the continuous graphical display of each of the parameters on the main data collection screen  50 , as well as the off-line data review screen (not shown, but is substantially the same as  50  with playback controls  36 ). These graphically displayed parameters include heart rate  56 , breath rate  60 , S p O 2    58 , pulse distention  52  and breath distention  54 . Graphs could also be added to include any parameters that may be developed in the future. The graphs  52 - 60  consist of continuous streaming plots of each parameter. The graphs are displayed on a data point basis, which can be considered a time based display, however technically the displays would be display a range of data points with the data points evenly distributed. As the range of data points corresponds to a range of time it is essentially a time based display. Because of the time-based display of these graphs  52 - 60 , they also allow the user to watch the response to a given input in an experiment. These graphical displays can be seen on the left-hand side of the display  50  of  FIGS. 4 and 5 . In the particular embodiment the sensor is a pulse oximeter such as sold under the brand Mouse Ox by Starr Life Sciences. 
         [0041]    The main data collection screen or display  50  of the interface of the present invention further includes the window  12 , and numerical displays  20 - 28  for the current data (chart data  44 ) and at a user selected location (curser data  46 ), and file marking control  30 , and numerical file marker indicator  32 , and a series of additional controls  64  for interfacing with the display  50 . The controls  64  include buttons to stop/start and pause the recording session and to bring up other displays, to close a display, and increase/decrease the visible gain on a selected graph. Other controls  64  can be added as interface further functions are desired. 
         [0042]    File Marker 
         [0043]    Associated with this benefit is the ability of the user to place a number of file markers in the recorded data file through control  30  to indicate some event in the experiment. A button  30  appears on the screens  10  and  50  that allows the user to place a marker in the data file to signify an event of his choosing. The file markers are placed in a separate column of data in the data file and are numbered sequentially starting at 1, which number is displayed to the user at text box  32 . Because the data files are saved in continuous time increments, the file marker will be located in the file at the same temporal location that the event of interest occurred, and can therefore be correlated with the response to that event of the other parameters in their respective columns. Note that a place holder is required for each temporal location in the data file. The file marker column continues to record the current value of the file marker until a new one is chosen by the user. Buttons  30  for the file marker function are shown on the right, bottom of the screen or display  50  shown in  FIGS. 4 and 5  discussed above. Also, on the graph  58  of Oxygen Saturation appear vertical blue lines  62  that indicate the temporal location of file marker&#39;s  1  and  2 . The file marker location lines  62  can be supplied on each graph  52 ,  54 ,  56 ,  58  and  60 . 
         [0044]    Note that there are other ways to mark the data files other than a number. One could save a given type character that does not have to be a number, or a sequential integral number at that location, then keep all zeroes (or other character) at all other locations in the file marker column. File marking could also be done by having the user strike a key on the computer keyboard rather than or in addition to having a mouse click on a button on the user screen. This could also be done with a touch screen. In addition, it will be beneficial if textual comments can be added to each file marker either contemporaneously with the session or with a later review of the session. 
         [0045]    Moving File Marker 
         [0046]    As described above, an indicator  62  is placed on the graphs  52 - 60  described above to allow the user to see the time at which a given event was marked. This file marker indicator  62  appears as a vertical line on the screen as shown and as described, and it follows the time point on the graph  52 - 60  at which it was implemented until that time point leaves the sweeping visible screen in the future. Movement of the file markers is indicated by comparing the location of the vertical blue lines on the Oxygen Saturation plot between the figures above and below. The  FIG. 5  shows the same run of data as the  FIG. 4 , except that it occurs some time later, as indicated by the movement of the vertical blue file marker lines  62  to the left (the screen scrolls from right to left). The curser data  44  time indication  42  is also indicative of a later time for the display  50  of  FIG. 5 . 
         [0047]    Variable Display for Quick Diagnosis 
         [0048]    A third idea is to display numerical values  20 - 28  of each parameter continuously during data collection, as described above for screens  10 ,  40  and  50 . This utility allows the user to continuously see the actual numerical values associated with each scrolling graph. Additionally, the user can lay the computer mouse cursor over the plot at a given temporal location and left-click (or right click or the like). This will place all of the currently updated parameter values in boxes under the curser data heading  46  on display  50  adjacent to those that display the updating values for each parameter. A right click on the screen will load the current values into these adjacent boxes so that they do not update. This allows the user to take snapshots for review of all of the data parameters at a given time, allowing the device to be used as a diagnostic tool as well as a data recorder. This functionality is also available in the off-line data file review software. 
         [0049]    Quick Diagnostic Screen 
         [0050]    Another concept of the present invention is an addition to the diagnostic utility of the pulse oximeter device (see  FIG. 6 ), is a new user screen  70  that can be selected by a control button  64  on the data collection screen  50 . This button  64  will pull up a new screen  70  shown in  FIG. 6  that displays numerical values  20 ′,  22 ′,  24 ′,  26 ′ and  28 ′ of each of the data parameters. This screen  70  is designed specifically to allow the user to obtain single value data points which are averages of the data for quick diagnosis. The additional utility of this screen  70  is that it provides the user with the ability to select a period over which serial data points are averaged for each parameter through controller  72 . The user can then indicate when to start the count with control  74 , and the software will average the selected serial data values over the chosen period set by controller  72  and display the final values when the average is completed in  20 ′- 28 ′. The prime reference numerals are used as the values are averages of the selected parameter measurements rather than the measurements themselves. This averaging is done for each of the parameter (heart rate  24 ′, breath rate  28 ′, S p O 2    26 ′, pulse distention  20 ′, breath distention  22 ′ and any other obtained parameter). Note that the averaging period could also be set using particular quantities of updated values as well as the time-based approach given here. Note also that the averaging could be done either forward or backward in time from when the Run New Diagnostic button  74  is pressed. 
         [0051]    Although the present invention has been described with particularity herein, the scope of the present invention is not limited to the specific embodiment disclosed. It will be apparent to those of ordinary skill in the art that various modifications may be made to the present invention without departing from the spirit and scope thereof. The scope of the present invention is defined in the appended claims and equivalents thereto.