Abstract:
An anesthesiology pump for automatic delivery and control of anesthetics to a patient provides a remote unit that may be carried by an anesthesiologist to improve supervision of the anesthesiology process without unnecessarily constraining the anesthesiologist&#39;s movement. The anesthesiology pump may assess one or both of a status of the anesthesiology procedure and the availability of the anesthesiologist to provide tailored alerts to the anesthesiologist when additional attention or availability may be needed. Availability may consider separation distance between the pump and the radiologist as well as express indications of availability. A set of predefined safe states permit a pump response when the anesthesiologist is not available and additional attention is required.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     Background of the Invention 
       [0001]    The present invention relates to medical pumps for the delivery of anesthetics during medical procedures and in particular to a pump that balances independent operation with features that allow improved supervision by an anesthesiologist. 
         [0002]    The delivery of anesthetics during medical procedures is normally supervised by a trained anesthesiologist who monitors a variety of physiological signals including blood oxygen, respiration rate, heartbeat, and brain waves in order to control the delivery of anesthetic to achieve a desired level of anesthesia. Recently, medical pumps have been developed that can perform many of these monitoring tasks and that can analyze the received data to make recommendations with respect to the adjustment of an anesthetic or actually control the anesthetic delivery. US patent application 2014/0180160 describes a system for monitoring a state of a patient during the administration of anesthetics to make recommendations with respect to drug administration. PCT patent application WO 2013184965 describes a system that monitors a patient during anesthesia to control anesthetic delivery. 
         [0003]    For many types of anesthesiology, it is desirable to have an anesthesiologist readily available on call in the event of a problem. Requiring close supervision of such automatic anesthesiology equipment or requiring immediate availability that prevents the anesthesiologist from performing other useful tasks, however, can be an inefficient use of highly skilled personnel. Even in cases where an anesthesiologist may effectively supervise multiple automatic anesthesiology devices that are properly functioning, should an emergency occupy the anesthesiologist on one task, the assumption of immediate availability for supervision of other anesthesiology devices may no longer hold presenting a gap in procedure. 
       Summary of the Invention 
       [0004]    The present invention provides an automatic anesthesiology delivery device that dynamically determines a confidence level with respect to patient data and the device&#39;s delivery of anesthetic. A remote communication device carried by the anesthesiologist provides the anesthesiologist with real-time monitoring of the anesthesiology process together with tailored alerts based on this confidence level and optionally with an imputed availability of the anesthesiologist. The result is an anesthesiology delivery device that assists both in delivery of anesthetic and ensuring effective supervision by an attending anesthesiologist. In cases where there is low confidence in the delivery but the anesthesiologist cannot be available, the anesthesiology device may enter a safe state predetermined according to a particular procedure being undertaken. 
         [0005]    In one embodiment, the invention provides a pump unit including a processor executing a program stored in non-transient media to receive physiological signals from a patient under anesthesia and to provide a controlled delivery of anesthesia to the patient in response to the received physiological signals and a remote unit communicating wirelessly with the pump unit to provide real time information to a remote anesthesiologist indicating a status of the anesthesiology procedure. 
         [0006]    It is thus a feature of at least one embodiment of the invention to better leverage time and resources of, a trained anesthesiologist monitoring automatic anesthesiology pumps. By duplicating faceplate features of the pump on a remote device, improved supervision and anesthesiologist flexibility can be achieved. 
         [0007]    The remote unit maybe sized and may communicate with the pump unit so that it may be carried by the anesthesiologist. In one embodiment, the remote unit may include a wristband for holding on an anesthesiologist&#39;s arm in the manner of a wristwatch. 
         [0008]    It is thus a feature of at least one embodiment of the invention to provide a remote terminal providing a high degree of mobility and also providing the ability to track the location of the anesthesiologist for accessibility purposes. 
         [0009]    The remote unit provides a display indicating values of at least some physiological signals and/or may provide a display indicating a qualitative status of the anesthesiology procedure, for example, by a color of an icon representing the pump unit. 
         [0010]    It is thus a feature of at least one embodiment of the invention to provide patient monitoring capabilities for the anesthesiologist as well as a quick assessment of the anesthesiology procedure. 
         [0011]    The pump unit may process the received physiological signals to determine a confidence interval with respect to the proper anesthetics state of the patient and further provides signals to the remote unit generating alerts selected from the group of visual, audible, or tactile alerts as a predetermined change in confidence interval. 
         [0012]    It is thus a feature of at least one embodiment of the, invention to provide intelligent alerts to the anesthesiologist to minimize distractions when intervention is not required. 
         [0013]    The remote unit may provide a display indicating a current confidence interval. 
         [0014]    It is thus a feature of at least one embodiment of the invention to permit the anesthesiologist to readily distinguish between different types of alerts. 
         [0015]    The pump unit may communicate with the remote unit to assess an availability of the anesthesiologist and the alerts may also be a function of the availability of the anesthesiologist. 
         [0016]    It is thus a feature of at least one embodiment of the invention to provide a system that optimizes anesthesiologist oversight both with respect to anticipated problems and anticipated response availability. 
         [0017]    The pump unit may determine the availability, of the anesthesiologist based on a distance between the pump unit and the anesthesiologist. 
         [0018]    It is thus a feature of at least one embodiment of the invention to impute low availability without action by the anesthesiologist. 
         [0019]    The assessed distance may be determined using wireless signals from the pump unit and remote unit. 
         [0020]    It is thus a feature of at least one embodiment of the invention to make use of the same wireless communication infrastructure needed for mobility for range measurement. 
         [0021]    The pump unit may also determine availability of the anesthesiologist at least in part by a self-reporting of availability by the anesthesiologist. 
         [0022]    It is thus a feature of at least one embodiment of the invention to permit the anesthesiologist to indicate lack of availability, for example, so that the pump unit may seek other alternatives. 
         [0023]    The pump unit may determine availability of the anesthesiologist at least in part by interaction by the anesthesiologist and the remote device for reviewing data on the remote device. 
         [0024]    It is thus a feature of at least one embodiment of the invention to provide a measurement of availability that reflects engagement by the anesthesiologist such as may reduce the need for alerts. 
         [0025]    The pump unit may provide internal diagnostics as to proper operation of the pump unit and wherein the alerts are also a function of an indication of failure of the pump unit. 
         [0026]    It is thus a feature of at least one;embodiment of the invention to use the same mechanism for anesthesiology alerts to signal equipment malfunction or risk malfunction. 
         [0027]    These particular features and advantages may apply to only some embodiments falling within the claims and thus do not define the scope of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0028]      FIG. 1  is a simplified perspective view of an anesthesiology pump for monitoring, a patient and providing automatic delivery of anesthetic and further showing a system for remote communication with an anesthesiologist; 
           [0029]      FIG. 2  is a fragmentary view of a wristband providing remote communication with the anesthesiology pump providing the anesthesiologist with both real-time data and tailored alerts to assist in monitoring one or more pumps; 
           [0030]      FIG. 3  is a hardware block diagram of the pump and remote monitor in one embodiment; 
           [0031]      FIG. 4  flowchart of a program executed, by the pump of  FIGS. 3 ; and 
           [0032]      FIG. 5  is an example plot of confidence versus availability showing alarm and safe state levels used to provide tailored alerts to the anesthesiologist; and 
           [0033]      FIG. 6  is an example display of the remote monitor of  FIG. 2  showing its capabilities for allowing monitoring of multiple anesthesiology pumps. 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0034]    Referring now to  FIG. 1 , an automatic anesthetic pump  10  may be placed bedside near a patient  12  to receive physiological signals from the patient from sensors including EEG electrodes  14 , a pulse blood oxygen monitor  16 , and other known sensors (not shown) including optionally a respiration sensor for monitoring breathing, a capnometer for monitoring exhaled carbon dioxide, and a reaction sensor for receiving input from the patient and providing tactile output. The anesthesiology delivery device  10  may also provide an earphone  47  for communicating with the patient  12 . 
         [0035]    In operation, the automatic anesthetic pump  10  operates to deliver and anesthetic  18 , for example, intravenously to the patient  12  as a function of the physiological signals from the patient  12  and internal operating rules. Examples of such systems are cited above in the background of the invention and are hereby incorporated by reference. The operating rules can be stored in the pump, or obtained remotely from a database server. 
         [0036]    In the present invention, the automatic anesthetic pump  10  may communicate with a remote anesthesiologist  20 , for example, by direct or indirect wireless communication including, for example, wireless protocols employing IEEE 801.11 or similar standards, as well as Bluetooth and the like. In one embodiment, the automatic anesthetic pump  10  provides wireless communication with one or more wireless access points  22 , the latter being part of a network of wireless access points. This network of wireless access points  22  may also communicate with a mobile unit  24  held by the anesthesiologist  20 . 
         [0037]    The wireless access points  22  may provide geotocation capabilities to identify one or both of the location of the automatic anesthetic pump  10  and the location of the anesthesiologist  20 , for example, by trilateralization or other known location technologies. Alternatively, the automatic anesthetic pump  10  may communicate directly with the mobile unit  24 , without the need for a network of wireless access points  22 , for example, by Bluetooth communication, and the Bluetooth communication channel used to determine a distance of the anesthesiologist  20  from the automatic anesthetic pump  10 . This distance or location information will be used to determine the availability of the, anesthesiologist  20 . 
         [0038]    Referring now to  FIG. 2 , in one embodiment, the mobile unit  24  may provide a display  28  having a wrist strap  26  to hold the mobile unit  24  on a wrist of the anesthesiologist  20  so that the display  28  is easily viewable by the anesthesiologist  20  in the maimer of a wristwatch. One or more user controls may be present on the exposed upper surface of the mobile unit  24  for access by the anesthesiologist  20  to control the display information on the display  28  and to provide other inputs from the anesthesiologist  20 , for example, inputs indicating unavailability of the anesthesiologist  20  for providing limited control of the automatic anesthetic pump  10 . As will be discussed, the mobile unit  24  may provide for alarm capabilities either in the form of an audible alarm, a flashing light, vibration, or a combination of these features. 
         [0039]    Referring now to  FIG. 3 , both the mobile unit  24  and the automatic anesthetic pump  10  may provide for wireless communication transceivers  32  either communicating directly with each other or indirectly through the wireless access points  22  (shown in  FIG. 1 ). In addition, these devices may each include processors  34  communicating with memory  36  which may hold stored programs  38  implementing the present invention. A user interface  40  on each device allows for the display of information and the input of information from a user. On the mobile unit  24 , the user interface  40  includes the display  28  and the user controls  30 . The mobile unit  24  may include one or more alarm, elements  39 , for example, a piezoelectric buzzer, a flashing light, or vibration motor for signaling the anesthesiologist  20 . The wireless communication transceiver  32  on the pump  10  may further provide for communication with a remote rule server (not shown) that may hold current clinical rules providing best practice for the delivery of anesthesia. During the control process provided by the pump  10 , these clinical rules may guide that control. The clinical rules may be held in the memory  36  and be upgradable, for example, by physical media attached to the pump  10  or over a network through the wireless connection or a wired connection. Alternatively, the clinical rules may be accessed in real time from a remote rule server which may assist in the control process. 
         [0040]    The automatic anesthetic pump  10  also provides a physiological signal interface circuit  42  receiving inputs from the EEG electrodes  14  and the other physiological sensors  44  including respiration, blood oxygen, pulse, and the like. The physiological signal interface circuit  42  also provides output to the earphone  47  for providing instructions to the patient as has been discussed. 
         [0041]    Importantly, the automatic anesthetic pump  10  includes a pump mechanism  46  for controlling delivery of the anesthetic  18 , for example, Propofol, Etomidate, Barbiturates, and the like using a peristaltic pump element  48 . The automatic anesthetic pump  10  may further include sensors  51  such as obstruction sensors, flow sensors, and the, like, communicating with the processor  34  and indicating whether the intravenous line to the patient  12  is operating properly. Pump mechanisms of this type and suitable for this purpose are described in U.S. Pat. Nos. 8,652,093 and 8,945,043 assigned to the assignee of the present application and hereby incorporated by reference. 
         [0042]    Referring now to  FIG. 4 , program  38  in the automatic anesthetic pump  10  may receive set up commands as indicated by process block  50 , for example, identifying the patient weight and name and confirming the installation and operation of the various physiological sensors  44  and the EEG electrodes  14 . This setup can be conducted through either of the user interfaces  40  of the automatic anesthetic pump  10  or the mobile unit  24 . 
         [0043]    Once the automatic anesthetic pump  10  is configured delivery of anesthetic may be started as indicated by process block  52 . This starting process may require the presence of the anesthesiologist  20  at the bedside either by requiring an input to the automatic anesthetic pump  10  itself or by measuring the proximity of the anesthesiologist  20  using the mobile unit  24 . 
         [0044]    Once started, the automatic anesthetic pump  10  begins the delivery of anesthetic as indicated by process block  54 . During this delivery, the physiological signals of the patient  12  are monitored and used to control the pump elements  48  (shown in  FIG. 3 ) to produce a desired anesthesiology level in a closed-loop process. Techniques for monitoring and providing control of this type arc described in the above-cited patents hereby incorporated in their entirety by reference. 
         [0045]    During the monitoring of process block  54 , data will be transmitted to the anesthesiologist  20  through the mobile unit  24  for on-demand viewing by the anesthesiologist  20  as indicated by process block  55 . 
         [0046]    At process block  56 , the monitored data and operation of the pump in delivering anesthetic may be analyzed and the delivery process assigned to a confidence interval. The confidence interval may provide an analysis of whether the data represents a normal anesthesiology session, for example, by comparing it to historical data either using ranges or supervised machine learning or the like. Alternatively, the confidence interval may be an analysis of the brain state of&#39;the patient  12  with respect to the desired level of anesthesia. Confidence intervals of this latter type are described, for example, in patent 2014/0180160 incorporated by reference. The confidence level may optionally incorporate both of these elements and/or internal diagnostics indicating proper operation of the automatic anesthetic pump  10 . 
         [0047]    A high confidence interval will generally indicate that the automatic anesthetic pump  10  is performing properly and that there is no particular concern that requires close monitoring by the anesthesiologist  20 . To the contrary, a low confidence interval generally indicates that attention by the anesthesiologist is required, not necessarily because there is a problem but possibly because the data is unfamiliar in some respect. At the lowest confidence interval levels, however, an error may be indicated or significant problems with the anesthesiology procedure that requires review by the anesthesiologist  20 . 
         [0048]    At decision block  58 , the confidence interval may be compared against an anesthesiologist availability assessment by the automatic anesthetic pump  10  assessing a current or predicted availability of the anesthesiologist  20 . This availability assessment may be a combination of the distance between the automatic anesthetic pump  10  and the mobile unit  24  (indicating physical distance separating the anesthesiologist  20  from the patient  12 ), a most recent viewing of data on the mobile unit  24  by the anesthesiologist  20 , and/or possible instructions by the anesthesiologist  20  entered through the mobile unit  24  indicating a lack of availability, for example, as a result of an emergency or the like, 
         [0049]    Referring also to  FIG. 5 , a combination of availability and confidence intervals may be used to define status zones guiding operation of the automatic anesthetic pump  10 . A first status zone  60  is generally associated with normal operation of the automatic anesthetic pump  10  in which the patient  12  is continually monitored and anesthetic levels controlled while data is sent to the mobile unit  24 . This first status zone  60  embraces both cases of low availability of the anesthesiologist  20  but high confidence in the operation of the automatic anesthetic pump  10  in controlling the anesthetic, and cases of lower confidence but high availability of the anesthesiologist  20 , for example, when the anesthesiologist  20  is at bedside. 
         [0050]    Further rightward from status zone  60  is status zone  62  which encompasses all error conditions and regions, to the right of status zone  60  where the availability of the anesthesiologist  20  is lower for each confidence level. Error conditions include internal diagnostics performed by the automatic anesthetic pump  10  including proper flow of anesthetic  18  as determined by sensors  51  which may determine obstruction and proper flow rate and proper operation of the internal electronics of the automatic anesthetic pump  10 , for example, using processor watchdogs and checksums on memory values and program instructions known in the art. In this status zone  62 , the anesthesiologist  20  will be given an alert either audible, visual, or tactile, indicating that immediate attention should be given to this patient and the automatic anesthetic pump  10  as indicated by process blocks  64  and  66 . 
         [0051]    At process black  66 , the mobile unit  24  may provide a range of different instructions to the anesthesiologist  20  as determined by sub zones  63  within status zone  62 , for example, to provide a response using user controls  30  confirming availability of the anesthesiologist  20  at a leftmost sub zone  63  or requesting that the anesthesiologist  20  return to the bedside, for example, at the rightmost sub zone  63 . If a response is not received, the availability of the anesthesiologist  20  may be predetermined to provide a decreased assessment of availability which in turn may trigger additional actions by the automatic anesthetic pump  10 . 
         [0052]    If the confidence interval is sufficiently low and/or the availability of the anesthesiologist  20  is sufficiently low, a status zone  68  may be entered to the right of status zone  62 . Entry into this status zone  68  is immediately transmitted to the mobile unit  24  with appropriate alerts and the automatic anesthetic pump  10  begins the process of moving the automatic anesthetic pump  10  into a safe state. A safe state may be defined for each procedure and drug type and does not necessarily involve shutting down the delivery of anesthesia although this is one option. In another option, the anesthetic level is reduced and additional alerts generated, for example, communicating with other hospital personnel or the like through the wireless access points  22 . An alarm may also sound on the automatic anesthetic pump  10  to alert other attending medical personnel. 
         [0053]    Referring now to  FIG. 6 , the display  28  of the remote device  24  may allow for simultaneous monitoring of multiple automatic anesthesiology delivery devices  10 , for example, each represented by an icon  70 . In one embodiment the icons  70  may each have a color indicating the status zones  60 ,  62  and  68  in which the respective automatic anesthetic pump  10  is operating and displaying important data necessary for the anesthesiologist  20 . This displayed data may depend on the context, for example, displaying pulse rate and oxygen for automatic anesthesiology delivery devices  10  in status zone  60 , but for status zone  62  and  68  displaying aberrant sensor data or the like as appropriately indicated, 
         [0054]    Certain terminology is used herein for purposes of reference only, and thus is not intended to be limiting. For example, terms such as “upper”, “lower”, “above”, and “below” refer to directions in the drawings to which reference is made. Terms such as “front”, “back”, “rear”, “bottom” and “side”, describe the orientation of portions of the component within a consistent but arbitrary frame of reference which is made clear by reference to the text and the associated drawings describing the component under discussion. Such terminology may include the words specifically mentioned above, derivatives thereof, and words of similar import. Similarly, the terms “first”, “second” and other such numerical terms referring to structures do not imply a sequence or order unless clearly indicated by the context. 
         [0055]    When introducing elements or features of the present disclosure and the exemplary embodiments, the articles “a”, “an”, “the” and “said” are intended to mean that there are one or more of such elements or features. The terms “comprising”, “including” and “having” are intended to be inclusive and mean that there may be additional elements or features other than those specifically noted. It is further to be understood that the method steps, processes, and operations described herein are not to be construed as, necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. It is also to be understood, that additional or alternative steps may be employed. 
         [0056]    References to “a microprocessor” and “a processor” or “the microprocessor” and “the processor,” can be understood to include one or more microprocessors that can communicate in a stand-alone and/or a distributed environment(s), and can thus be configured to communicate via wired or wireless communications with other processors, where such one or more processor can be configured to operate on one or more processor-controlled devices that can be similar or different devices. Furthermore, references to memory, unless otherwise specified, can include one or more processor-readable and accessible memory elements and/or components that can be internal to the processor-controlled device, external to the processor-controlled device, and can be accessed via a wired or wireless network. 
         [0057]    As used herein programming or data entry refers not only to adding data but modifying or deleting data in electronic memory. 
         [0058]    It is specifically intended that the present invention not be limited to the embodiments and illustrations contained herein and the claims should be understood to include modified forms of those embodiments including portions of the embodiments and combinations of elements of different embodiments as come within the scope of the following claims. All of the publications described herein, including patents and non-patent publications are hereby incorporated herein by reference in their entireties.