Abstract:
Display objects are defined that are capable of visually indicating physiological measurements and physiological monitor status. A virtual display utilizing these display objects is characterized by selecting those display objects corresponding to one or more particular physiological parameters, organizing the selected display objects within a virtual display area corresponding to at least a portion of a physical display, and associating data objects corresponding to the one or more physiological parameters with the selected display objects.

Description:
PRIORITY CLAIM TO RELATED PROVISIONAL APPLICATIONS 
     The present application claims priority benefit under 35 U.S.C. §119(e) to U.S. Provisional Patent Application Ser. No. 60/755,899, filed Jan. 3, 2006, entitled “Virtual Display.” The present application incorporates the foregoing disclosure herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     A conventional multiple parameter measurement system (MPMS) has a parameter processor and a host processor. The parameter processor may be an OEM board or plug-in that connects to and drives a sensor and computes one or more physiological parameters from the resulting sensor signal. The host processor communicates with the parameter processor so as to receive and display these parameters. As examples, a MPMS may display arterial oxygen saturation (SpO2), pulse rate, ECG waveforms, blood pressure and body temperature, to name a few. 
     SUMMARY OF THE INVENTION 
     A conventional MPMS typically requires hardware or software modifications in order to measure and display a new and useful parameter, such as a physiological measurement resulting from a technological advance. A virtual display advantageously generates a display for a previously undefined, unmeasurable or unknown measurement without complex system modifications. In one embodiment, a virtual display can be flexibly characterized so that a MPMS that is upgraded to measure a new parameter can readily display that parameter. 
     One aspect of a virtual display defines display objects capable of visually indicating physiological measurements and physiological monitor status. A subset of the display objects corresponding to a physiological parameter is selected. The selected display objects are organized within a virtual display area corresponding to at least a portion of a physical display. Data objects corresponding to the physiological parameter are associated with the selected display objects. 
     Another aspect of a virtual display is a physiological parameter measurement system comprising a virtual display, a parameter processor and a host processor. The parameter processor is adapted to input a sensor signal and output a physiological parameter responsive to the sensor signal. The host processor is in communication with said parameter processor, and the virtual display resides in the host processor. The parameter processor has a characterization for the virtual display that corresponds to the physiological parameter. That characterization is communicated to the host processor so as to enable the host processor to display the physiological parameter. 
     A further aspect of a virtual display comprises a virtual display area, a display object, a display layout and a data setup. The virtual display area corresponds to at least a portion of a physical display. The display objects are allocated to the display area. A display layout specifies at least the size and location of the display objects within the virtual display area, and a data setup associates the data objects with the display objects. The display objects are selected to visually indicate measurements of one or more particular physiological parameters on the physical display. The data objects identify measurements of the physiological parameters and information associated with the measurements. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a block diagram of a multi-parameter measurement system (MPMS) incorporating a virtual display; 
         FIG. 2  is a flow diagram for a virtual display; 
         FIG. 3  is an illustration of exemplar display objects; 
         FIG. 4  is an illustration of an exemplar display layout utilizing selected display objects; and 
         FIG. 5  is an illustration of an exemplar display data setup. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       FIG. 1  illustrates a multi-parameter measurement system  100  (MPMS) configured with a virtual display. The MPMS comprises a parameter processor  110  and associated sensor port  10 , a host processor  120  and a display  130 . The parameter processor  110  is configured to receive signal processing and sensor control upgrades so that the parameter processor  110  is able to interface with new or upgraded sensors and able to measure previously undefined, unmeasurable or unknown, i.e. “new” physiological parameters. In one embodiment, the MPMS  100  is upgraded via the sensor port  10 . A sensor port upgrade capability is described in U.S. Pat. Pub. No. 2005/0075548, entitled Multipurpose Sensor Port, assigned to Masimo Corporation, Irvine, Calif. and incorporated by reference herein. In another embodiment, the parameter processor  110  is a plug-in containing a new parameter measurement capability that is inserted into the MPMS  100 . 
     As shown in  FIG. 1 , the MPMS  100  advantageously incorporates a virtual display  201  that enables the MPMS  100  to readily display a new physiological parameter. In particular, the virtual display  201  resides on the host processor  120 . A parameter upgrade loaded into the parameter processor  110  provides information in a predetermined format that characterizes the virtual display  201 , i.e. describes how the MPMS  100  should display a new physiological parameter. The MPMS  100  may also have a keypad  140 , an alarm  150 , communications  160  and an associated I/O port  20  that provide status to the virtual display  201  according to the parameter upgrade. A virtual display  201  is described in detail with respect to  FIG. 2 , below. 
       FIG. 2  illustrates virtual display functions  200 , which are divided between parameter processor functions  201  and host processor functions  202  and also between characterization functions  210  and operation functions  260 . During characterization  210 , the parameter processor  110  ( FIG. 1 ) prepares the host processor  120  ( FIG. 1 ) to display one or more new parameters. During operation  260 , the parameter processor  110  ( FIG. 1 ) provides the new parameter or parameters to the host processor  120  ( FIG. 1 ) for display according to the prior characterization. In one embodiment, the virtual display characterization  210  determines how data is to be displayed, such as a waveform, a bar graph or a numeric readout; how the display is organized, such as the size and layout of readouts and labels on a physical display space; and which data goes where on the display. Then, during operation  260 , the parameter processor provides measurement data for the virtual display  201 , and the host processor  120  ( FIG. 1 ) communicates the virtual display  201  to the physical display  130 . 
     As shown in  FIG. 2 , characterization  210  includes the parameter processor functions  201  of display object specification  220 , display object association  230  and data object association  240 . Display objects are display mechanisms or formats used to present parameter measurements and processor status on a display  130  ( FIG. 1 ). Display objects may include, for example, various graphs, alphanumeric readouts and visual indicators. The display object specification  220  informs the host instrument which of various predefined display objects will be used to display one or more new parameters and corresponding monitor status. 
     The display object association  230  informs the host instrument of a desired organizational schema for the display objects, i.e. the spatial relationships and any other correspondence between the various display objects on the display. For instance, the host processor may need to locate an alphanumeric object immediately adjacent to a graphical object in order to display a waveform and a corresponding label identifying the waveform. 
     The data object association  240  informs the host instrument of the various data types, how those data types are to be recognized by the host instrument, and which data types are associated with which previously specified display objects. For example, plethysmograph data output from the parameter processor may map to a specific graphical display object. 
     Further shown in  FIG. 2 , characterization  210  also includes the host processor functions  202  of display object selection  300 , display layout  400  and display data setup  500 , which correspond to the parameter processor functions  201  described above. Display object selection  300  is a response to display object specification  220 . In particular, the host processor selects one or more predefined display objects that the display object specification  220  identifies for use in a newly configured display. 
       FIG. 3  illustrates various display objects  300  including, as examples, a waveform magnitude vs. time graph  310 , a numeric readout  320 , an alphanumeric label  330 , a bar graph  340 , trend indicators  350 , a visual alarm  360  and a battery charge indicator  370 . One of ordinary skill in the art will recognize many other possible display objects useful for visually indicating, for example, physiological measurements and monitor status. 
     As shown in  FIG. 2 , display layout  400  is a host processor response to display object association  230 . In particular, the host processor organizes selected display objects, such as described with respect to  FIG. 3 , above, within a virtual display area. The virtual display area may correspond to an entire physical display or a newly allocated portion of a physical display utilized for simultaneous monitoring of multiple physiological parameters. In particular, the host processor utilizes known characteristics of the selected display objects along with the organizational schema provided by the display object association  230  to generate a layout for a newly defined display. 
       FIG. 4  illustrates an example of a display layout  400  having a virtual display area  401 , a first display area portion  403  allocated for previously defined parameters, such as ECG, temperature (T) and noninvasive blood pressure (NIBP) in this example, and a second display area portion  405  allocated for newly defined parameters. The display layout  400  locates and organizes selected display objects  300  ( FIG. 3 ) including a waveform graph object  310 , a numeric readout object  320 , two label objects  330  and an visual alarm object  360  within the second display portion  405 . In particular, the display layout  400  responds to the display object association  230  constraints that a first label  330  is adjacent and to the right of the numeric readout  320  and a second label  330  is adjacent and below the visual alarm  360 . Other constraints may include the relative size and location of the waveform object  310 . The functionality of the resulting display layout  400  is described further with respect to  FIG. 5 , below. 
     Additionally shown in  FIG. 2 , display data setup  500  is a response to data object association  240 . In particular, the host processor associates parameter processor identified input data with particular display objects located within the allocated display area  403  ( FIG. 4 ). Input data may be identified according to a physical input port or a data header or similar code within a data stream, or both. 
       FIG. 5  illustrates one example of a display data setup  500  having various data objects  510 - 550  associated with various display objects  310 - 360  within a display area  405 , so as to form an operational virtual display  201  ( FIG. 1 ). During operation, data comprising measured parameters from the parameter processor and possibly status or other data from the parameter processor  110  ( FIG. 1 ), host processor  120  ( FIG. 1 ), keypad  140  ( FIG. 1 ) or communication interface  160  ( FIG. 1 ) is transferred to the display objects  310 - 360  of the virtual display  201  ( FIG. 1 ). The virtual display  201  ( FIG. 1 ) is then communicated to the physical display  130  ( FIG. 1 ), as described above. In this particular example, a plethysmograph data object  510  is associated with the waveform object  310 ; a calculated saturation or pulse rate data object  520  is associated with a numeric readout object  320 ; a “%” or “BPM” text object  530  is associated with a first label object  330 ; a “SpO2” text object is associated with a second label object  330  and an on/off command object  540  is associated with a visual alarm object  540 . The result is an operational pulse oximetry display. 
     Although a virtual display is described above with respect to a MPMS having a parameter processor and a host processor, in another embodiment, a physiological measurement system comprises a signal processor that functions as both a parameter processor and a host processor, as described above, with the signal processor incorporating a virtual display. A virtual display has been disclosed in detail in connection with various embodiments. These embodiments are disclosed by way of examples only and are not to limit the scope of the claims that follow. One of ordinary skill in art will appreciate many variations and modifications.