Abstract:
A system and a method are described for allowing a user to generate a timeline and display patient data with varying time intervals. The time intervals can range from a few minutes to several hours. By allowing a user to select start time and end time when a time interval change occurs, the time interval change is applied to a selected portion or duration of the timeline rather than the full length. Also multiple time intervals may be selected and applied to the patient data.

Description:
CROSS REFERENCE TO RELATED APPLICATION  
       [0001]    This application claims the benefit of a provisional U.S. application, U.S. Serial No. 60/374,912, filed Apr. 23, 2002, in the names of the present inventors. 
     
    
     
       FIELD OF THE INVENTION  
         [0002]    The present invention generally relates to a system and a method for processing and displaying of medical information, and more particularly, to processing and displaying of patient data. In one exemplary aspect, the present invention enables a user of a charting system to create an adaptive timeline for display of patient data.  
         BACKGROUND OF THE INVENTION  
         [0003]    In today&#39;s medical environment, various patient data is generated during a patient&#39;s stay in a hospital. The patient data is either stored electronically or written down on paper, depending on types of data and level of automation for a particular hospital. The type of data may include parameter settings for a piece of medical equipment used to treat a patient or parameter values obtained relating to physiology of a patient.  
           [0004]    For example, various types of medical equipment are used to monitor or administer care to patients in different hospital departments. In a critical care unit, a ventilator is frequently used to ventilate a patient&#39;s lungs with breathing gas when the patient&#39;s ability to breathe on his or her own is impaired. In order to properly administer ventilation, a caregiver needs to first set up various settings for the ventilator. Examples of commonly required settings to control a ventilator include: Peak Inspiratory Pressure (PIP) setting for limiting the peak pressure during inspiration of air; and Positive End Expiratory Pressure (PEEP) setting for limiting the peak pressure at the end of expiration of air. Many other ventilator settings may also be controlled, depending on the capability of the particular ventilator.  
           [0005]    Likewise, medical equipment may also be equipped with various physiological sensors so that the condition of a patient may be monitored. For example, commonly monitored parameters for a ventilator include Mean Airway Pressure (MAP) for indicating the mean pressure measured within the airway during the breathing cycle, and Tidal Volume Inspired (TVi) for measuring volume of gas inhaled by a patient during a normal breath. Of course, other different patient parameters may be monitored by other types of medical devices.  
           [0006]    In addition, hospitals also have laboratories to analyze, for example, blood of a patient. The results of the blood tests may be printed out by a lab technician and given to a caregiver or entered electronically on a computer to be accessed by the caregiver. The caregiver can then analyze the results and choose a correct course of treatment for the patient.  
           [0007]    The various exemplary patient data for a patient during his or her stay is now frequently stored electronically and often in a networked environment. A care provider may then access the data using, for example, web browser software through a network. This allows a caregiver to access the data throughout the hospital or even remotely through Internet.  
         SUMMARY OF THE INVENTION  
         [0008]    The present inventors recognize that during a patient&#39;s stay in a hospital, the patient&#39;s vital signs are collected at different rates depending on, for example, the health of the patient. In particular, if the patient&#39;s vital signs are tracked on a paper flow sheet, the data is likely to be written down using time intervals at which the data has been collected by a caregiver. It is therefore desirable to have a variable time interval capability for an electronic patient charting system that allows hospitals to convert patient data from paper to digital storage.  
           [0009]    Although previous systems may allow the time interval to be adjusted, the change is applied to the entire length of the patient&#39;s stay. By universally changing the time interval, prior systems display either too much or too little data for some portion of the patient&#39;s record. In contrast, the present invention allows resulting patient record to reflect data as a caretaker would have written it. Thus, during a critical period, the caretaker is free to concentrate on the patient knowing that data will be correctly entered on the patient&#39;s flow sheet later. When the crisis is over, the caretaker can select the appropriate time interval for that critical time period or duration. At that point, data is automatically collected and copied into the patient record efficiently.  
           [0010]    Therefore, in one exemplary aspect of the present invention, a system and a method for processing medical information are described. A user is allowed to select a time interval applicable to a timeline on a patient data screen. A user is also allowed to select a start time and an end time identifying a duration for which the selected time interval is applicable. Patient data is then displayed with the timeline such that the selected time interval is used for the duration between the selected start time and the selected end time. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    In the drawing:  
         [0012]    [0012]FIG. 1 is an exemplary process according to the present invention.  
         [0013]    [0013]FIG. 2 shows an example of a user interface screen according to the present invention.  
         [0014]    [0014]FIG. 3 is another example of a user interface screen having a start time and end time selection tool.  
         [0015]    [0015]FIG. 4 is a user interface screen showing a list of applicable start time choices in response to a user request.  
         [0016]    [0016]FIG. 5 is a user interface screen showing a tool for accepting data edits, changes and validation.  
         [0017]    [0017]FIG. 6 is an exemplary system according to the present invention. 
     
    
     DETAILED DESCRIPTION  
       [0018]    [0018]FIG. 1 shows an exemplary method employed by a system for processing and displaying patient data according to the present invention. FIG. 2 shows an exemplary user interface screen for a patient flow sheet which may be employed by the present system. An exemplary patient flow sheet or patient chart  200  in FIG. 2 comprises a timeline  201 . The timeline  201  is divided into time intervals for displaying patient data in each time interval. In this example, the timeline  201  is divided into 15-minute intervals as shown in FIG. 2.  
         [0019]    According to the principles of the present invention, the present system allows a user to select a time interval for a timeline via a list of available intervals, at step  104  of FIG. 1. A user may select an interval from, for example, a user interface popup icon  202  of flow sheet display screen  200  of FIG. 2. For example, when a user selects a down arrow  204  of FIG. 2, a list of available intervals is displayed. An exemplary list of available intervals (not shown) may comprise intervals such as 3 minutes, 5 minutes, 15 minutes, 30 minutes, 1 hour, 2 hours, 4 hours, etc.  
         [0020]    Once a time interval is selected at step  104  of FIG. 1, the system determines in step  106  which allowable start time and end time choices are applicable to the selected interval on the flow sheet based on a predetermined set of rules. The determination of allowable start time and end time choices is based at least in part on the interval chosen at step  104  and the time currently being displayed on the flow sheet. An example of a predetermined set of rules for presenting applicable start and end time choices to a user may be:  
         [0021]    1) for all intervals, change or start time occurs on the hour;  
         [0022]    2) if the selected interval is a 2 hour interval, the change or start time needs to occur on an even hour;  
         [0023]    3) if the selected interval is a 4 hour interval, the change or the start hour needs to be in the set of. (0:00, 4:00, 8:00, 12:00, 16:00, and 20:00);  
         [0024]    4) in order for an hour to be a candidate for the start time, it needs to currently appear on the flow sheet being used.  
         [0025]    In general, the purpose of these rules is to create a timeline that is logical and understandable to the user, while protecting the integrity of patient data. For example, the last rule above applies to disallow certain user selections in the following way, when a flow sheet is being displayed with a 4-hour interval. In that case, if the hours currently shown on the flow sheet are 4:00, 8:00, and 12:00, the user may not choose to switch to a 1-hour interval at 11:00 because this would cause a discontinuity in the data. Also, the interval between 8 and 11 is three hours, and that is not a valid interval for the example given.  
         [0026]    In addition, if the time interval has changed in the middle of the hour to a 1-hour mode, none of the columns following the change would occur on the hour, if not for the rules. It is unlikely that the user has intended this result when 1-hour mode has been selected. Therefore, the present system incorporates rules for presenting patient data in a flow sheet that further enhances user actions.  
         [0027]    Once the system determines the applicable start and end times based on a set of predetermined rules as shown in step  106  of FIG. 1, the system allows a user to select a particular start time and a particular end time at steps  108  and  110  of FIG. 1.  
         [0028]    At step  108  of FIG. 1, the system provides default settings for the start time and the end time. For example, as shown in an exemplary user screen  300  of FIG. 3, a start time and end time selection tool  304  is displayed when the user selects an interval. The selection tool  304  is populated with a predetermined default start time and a predetermined default end time  306  and  308  respectively, when the selection tool  304  is first displayed.  
         [0029]    The allowable default start time is also governed by the predetermined rules as described in connection with step  106  of FIG. 1. For example, as shown in flow sheet screen  300  of FIG. 3, the default start time is the current time (i.e., now). When this is restricted by the exemplary set of predetermined rules, the default start time of now becomes “11:00” as shown in  306  of FIG. 3. This is because the user-selected interval for this default start time is “15 Minutes” as shown in  312  of FIG. 3, and the current time for flow sheet  300  is “11:56” as shown in  310  of FIG. 3.  
         [0030]    An example of a default end time shown in FIG. 3 is a blank entry  308  indicating that the default end time for applying the selected time interval is indefinitely extended into the future. Therefore, if the user accepts the exemplary default values as shown in selection tool  304  of FIG. 3, the time interval change takes place from now into the future until the settings are changed.  
         [0031]    Additionally, the present system provides a list of available start time and end time choices automatically for a user. At step  110  of FIG. 1, the system displays all allowable start time and end time choices in response to a user request. This is illustrated in an exemplary flow sheet screen  400  of FIG. 4. For example, once a user selects a down arrow  404  of FIG. 4, a pop up screen  406  will be displayed with a list of the allowable start times as determined by, for example, the rules described at step  106  of the exemplary process flow of FIG. 1.  
         [0032]    At step  112  of FIG. 1, the user may accept the start time and end time choices selected by the user by clicking on, for example, “Accept” icon  410  of FIG. 4. The selected interval change occurs for the timeline between the accepted start time and end time.  
         [0033]    Using the same or similar sequence as described in steps  104  to  112  of FIG. 1, a user may select another interval to be applied to a duration or time period between a different start time and end time of the timeline. This allows the system to display patient data using one or more intervals on the same timeline.  
         [0034]    Whenever an interval change involves the past, the data shown in a flow sheet changes. If the interval is decreased, more patient data is charted, and if the interval is increased some data is removed from the chart. When additional patient data is required, it may be gathered from a raw data pool in the system database, and the chart is automatically filled in.  
         [0035]    One function of a patient chart or flow sheet is to allow the user to edit, change and/or validate patient data. This process is shown in an exemplary flow sheet display  500  of FIG. 5. As shown in FIG. 5, a user may highlight a portion of the flow sheet  500  with a user selection tool such as a cursor (not shown). Once the portion of the data is highlighted, an edit screen  502  is displayed which allows the user to examine and change if necessary the values of patient data. Once the user has examined and/or changed the data, the user can then select “Accept” icon  504  to indicate that the user has validated the data.  
         [0036]    In one aspect of the present invention, if data on a flow sheet has been edited, changed, and/or validated, the system assumes that it would be incorrect to remove that portion of the data from the chart. Therefore, one advantage of the present invention is to protect the user from inadvertently removing accepted data. The potential removal of data can occur for example, when a user changes a 1-hour interval to a 4-hour interval. Therefore, one embodiment of the present system automatically determines if an interval change requested would remove data that has been changed and/or validated. If that is the case, the interval change requested is ignored by the system, and a message is displayed which explains the problem to the user.  
         [0037]    For data that has not been changed or accepted, there is no issue in removing the data from the chart. The data still resides in a raw data pool elsewhere in the system database either locally or remotely in a server.  
         [0038]    [0038]FIG. 6 describes an exemplary system in accordance with the present invention. System  50  may comprise a general purpose computer or a specially constructed computer. A general purpose or specially constructed computer may be used with a program or programs in accordance with the teachings herein. An example of general purpose computer may be an Intel® based personal computer, capable of running MS Windows®. An example of a specialized machine may be a patient data display system for used in a hospital.  
         [0039]    The exemplary process of the present invention as shown in FIG. 1 may be implemented using an exemplary system illustrated in FIG. 6. System  50  of FIG. 6 comprises an input/output (I/O) section  51  which is used to communicate information in an appropriate form to and from other components of system  50 . I/O section  51  may also communicate with a local area or wide are network  67 , including the Internet, via for example, TCP/IP protocol. This allows system  50  to communicate with other computers or devices  69  over the network  67 , via for example, a web browsing software such as Microsoft Internet Explorer®.  
         [0040]    In addition, system  50  comprises a central processing unit (CPU)  52  coupled to I/O section  51 , and a memory  53  such as RAM and/or ROM for storing computer programs and other information to be executed. An example of a computer program which may be executed by system  50  is a process illustrated in FIG. 1.  
         [0041]    System  50  includes a display  60 , such as, for example, a CRT monitor, a liquid crystal display (LCD), or others. As illustrated in FIG. 6, a user interface screen  62  is displayed on display  60 . An example of a display screen  62  is shown, for example, as display screen  200  of FIG. 2 or screen  300  of FIG. 3.  
         [0042]    System  50  further includes a cursor control  54 , such as, for example, a mouse, a track ball, joystick or other device for selectively positioning a cursor  59  on a display screen  62  of the display  60 . Typically, cursor control  54  includes a signal generator, such as a switch  55  which a user of the computer system may use to generate signals directing the computer to execute certain commands which have been focused or enabled by the cursor control  54 . System  50  also includes a keyboard  56  to input data and commands from a user, as is well known in the art.  
         [0043]    Also shown in FIG. 6 is a mass storage device  58 , such as a hard disk, coupled to I/O circuit  51  to provide additional storage capability for computer  50 . In addition, a CD/DVD ROM  57  is further coupled to I/O circuit  50  for additional storage capacity or as another I/O device. It will be appreciated that additional devices (not shown) may be coupled to computer  50  for various purposes, as well known in the art.  
         [0044]    The described system and method may be advantageously applied to any system, including a web-based system, needing to display data with variable time granularity. There are no other restrictions on how often a time interval changes may occur. The user can always update the timeline, even if it has been previously changed. The described variable interval timeline system may be applied to any data that is displayed on a timeline. One aspect of the system is its ability to display data on a timeline where different time intervals that are shown concurrently for patient data. Another aspect is the system ability to change a patient chart&#39;s timeline interval in the past and the future.  
         [0045]    It is to be understood that the embodiments and variations shown and described herein are for illustrations only and that various modifications may be implemented by those skilled in the art without departing from the scope of the invention.