Abstract:
An infusion pump including an optical imaging and an RFID reading module connected thereto through a host interface. The optical imaging and RFID module comprises a system microcontroller that interconnects an optical image capture subsystem and an RFID subsystem preferably routed through a single interface to the infusion pump. This infusion pump controls operation of the optical imaging and RFID module through commands provided through the interface and, as a result, capable of obtaining data encoded on barcodes and RFID tags. The infusion pump, through the optical imaging and RFID module, may thus automatically retrieve patient data, pharmacological information, dosage amounts, etc. from barcodes or RFID tags applied to the patient, intravenous medication, and even medical staff.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     The present application is a continuation-in-part of application Ser. No. 11/308,170, filed on Mar. 9, 2006. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     The present invention relates to image capture and data collection systems and, more specifically, to a system and method for integrating radiofrequency identification and optical imaging with an infusion pump. 
     2. Description of Prior Art 
     Infusion pumps are important for the administration of intravenous (IV) therapy are designed to improve the accuracy and continuity of IV infusions by allowing nurses to program an hourly infusion rate and volume. Approximately 90% of hospitalized patients receive IV medications, a large portion of which are delivered by infusion pumps. Infusion pumps are often involved in one of the leading causes of medical injuries, referred to as adverse drug events. Most infusion pump-related errors occur because the pump is programmed with incorrect settings by the medical staff. For example, leaving out a decimal point or adding a zero when setting the infusion rate can easily result in a overdose. Alternately, infusion pumps may be inadvertently programmed to administer micrograms per kilogram per minute instead of micrograms per minute. Finally, there is no link at the bedside between the patient and type of drug being administered. Conventional infusion pumps thus lack the ability to independently verify the appropriateness of the manual programming performed by the medical staff to the patient at the bedside. 
     Recent attempts to overcome the limitations of infusion pumps involve the integration of “smart” infusion pumps with hospital patient and medical databases. Before using smart pumps at the bedside, a facility programs the pumps with its own specific data sets, or “profiles.” These profiles specify the infusion requirements for different patient types and care areas, such as pediatric, adult, obstetrics, oncology, anesthesia, ICU, and post-anesthesia care units. Each profile includes a drug library that contains hospital-defined drug infusion parameters, such as acceptable concentrations, infusion rates, dosing units, and maximum and minimum loading and maintenance dose bolus limits, for 60 or more medications. The infusion pump will then alert the user if an infusion program is outside of recommended parameters, such as dosage, dosing unit (mcg/kg/min, units/hr, etc.), rate, or concentration. Although some infusion pumps are capable of communicating remotely with hospital databases, thereby avoiding the need for extensive programming prior to use, the risk associated with human entry of data remains. 
     SUMMARY OF THE INVENTION 
     It is a principal object and advantage of the present invention to provide a system and method for improving the safe use of infusion pumps. 
     It is an additional object and advantage of the present invention to provide a system and method for verifying the appropriateness of drug delivery performed by an infusion pump. 
     It is a further object and advantage of the present invention to provide a system and method for reducing the number of adverse drug events associated with the use of infusion pumps. 
     It is an additional object and advantage of the present invention to provide a system and method for automatically inputting data into an infusion pump. 
     Other objects and advantages of the present invention will in part be obvious, and in part appear hereinafter. 
     In accordance with the foregoing objects and advantages, the present invention comprises an infusion pump that includes an optical imaging and an RFID reading module connected thereto through a host interface. The module of the present invention comprises a system microcontroller that interconnects an optical image capture subsystem and an RFID subsystem through a single interface to a host computer. The system microprocessor is configurable via the infusion pump or an external host to selectively provide RFID reading or writing, optical imaging, barcode reading, or a variety of combinations of both techniques in combination with the infusion pump. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The present invention will be more fully understood and appreciated by reading the following Detailed Description in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view of a combined RFID and optical imager module according to the present invention. 
         FIG. 2  is a schematic of a combined RFID and optical imager module according to the present invention. 
         FIG. 3  is a flowchart of main-line processing of a combined RFID and optical imager module the according to the present invention. 
         FIGS. 4A and 4B  are flowcharts of trigger command processing in a combined RFID and optical imager module according to the present invention. 
         FIG. 5  is a schematic of an infusion pump according to the present invention. 
         FIG. 6  is a flowchart of control processing in infusion pump according to the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring now to the drawings, wherein like numerals refer to like parts throughout, the present invention comprises an infusion pump including RFID and optical imaging capabilities. RFID and optical imaging capabilities are preferably provided via a combined RFID and optical imaging module that is interfaced with an infusion pump, or retrofit into an existing infusion pump, through a preexisting interface to provide RFID reading and optical imaging capabilities. 
     There is seen in  FIG. 1  a combined RFID and optical image module  10  according to the present invention that may be used in connection with an infusion pump. Module  10  generally comprises a microcontroller  12  that interconnects a first submodule, such as an optical imager  14 , and a second submodule, such as an RFID unit  16 , to a single host interface  18 . Alternatively, module  10  is capable of interconnecting any variety of data capturing devices as submodules and providing host controllability, including optical imagers, RFID transceivers, lasers, scales, thermometers or temperature probes, etc., in any variety of combinations. Module  10  may be arranged on a single printed circuit board  22  and encased as a single unit or housing. Integration of imager  14  and RFID unit  16  through interface  18  allows for combining control of operation of both submodules, such as RFID reading and barcode, through module  10 , as will be explained in detail hereinafter. 
     Referring to  FIG. 2 , a first submodule of module  10  is illustrated as an optical imager  14  comprising an image engine  20  having image processing circuitry interconnected to microcontroller  12  for omni-directional optical scanning. Image engine  20  controls an image sensor  24 , such as a complementary metal oxide semiconductor (CMOS) image sensor, and is capable of capturing two-dimensional images of 1D linear barcodes, 2D stacked/matrix barcodes, standard optical character recognition (OCR) fonts, Reduced Space Symbology (RSS) barodes, and postal barcodes, as well as providing image captured images for use in a wide range of applications, such as image and shape recognition, signature capture, image capture, and non-standard optical character recognition. Imager  14  may further include an illumination source  26  connected to engine  20 , such as one or more light emitting diodes (LEDs) of various wavelengths, to enhance illumination, operation, and image capture. For example, module  10  may include red LEDs for general illumination and green LEDs for targeting. Imager  14  may comprise, but is not limited to, an IT4X10/80 SR/SF or IT5X10/80 series imager available from Hand Held Products, Inc. of Skaneateles Falls, N.Y. that is capable of scanning and decoding most standard barcodes including linear, stacked linear, matrix, OCR, and postal codes. Specifically, the IT5X10/80 series imager is a CMOS-based decoded output engines that can read 2D codes, and has image capture capabilities sufficient for use with module  10 . 
     Imager  14  obtains an optical image of the field of view and, using preprogrammed algorithms in image engine  20 , deciphers the context of the image to determine the presence of any decodable barcodes, linear codes, matrix codes, and the like. Image engine  20  may be programmed to perform other image processing algorithms on the image captured by imager  14 , such as shape recognition, match filtering, and other high-level processing techniques. Alternatively, a captured image may be processed by microprocessor  12 , albeit with a decreased level of performance due to the additional communication time needed to transfer images from image engine  20  to microprocessor  12 . 
     Second submodule of module  10  may comprise an RFID unit  16  including an RFID transceiver  30  and associated RFID antenna  32  supporting standard RFID protocols, such as the TI Tag-it transponder protocol or ISO 15693. For these protocols, transceiver  30  operates at 13.56 MHz, and may comprise a S6700 Multi-Protocol Transceiver IC available from Texas Instruments of Dallas, Tex. Depending on the application, other frequency transceivers may be more appropriate based on target range, power availability, cost, etc. RFID unit  16  may further include a speaker or LED (not shown) for audibly indicating a successful interrogation of an RFID tag. 
     Antenna  32  is preferably a loop antenna of various sizes and turns implemented on a printed circuit board and connected to module  10 , or a wire loop installed antenna installed directly onto module  10 . Antenna  32  may be positioned remotely, thereby reducing the footprint of module  10  using an external connector, such as a MMCX coaxial connector. RFID transceiver  30  may be programmed to interrogate passive or active tags, process signals received from such tags (e.g., analog to digital conversion), and provide the information from the tags to microcontroller  12  for further processing or transmittal to a host computer via interface  18 . 
     Host interface  18  comprises a host transceiver  34  and a host connector  36  for interconnection to a host device  38 . Interface  18  may comprise a conventional RS232 transceiver and associated 12 pin RJ style jack. For example, an ADM202EARN available from Analog Devices, Inc. of Norwood, Mass. is a suitable RS-232/V.28 interface device having compliant levels of electromagnetic emissions and immunity. Alternatively, interface  18  may comprise other conventional buses, such as USB, IEEE 1394, 12C, SPI, or PCMCIA, or other connector styles, such as an FFC style to an embedded host or another module  10 . Interface  18  may also comprise a wireless transceiver in lieu of connector  36  for wireless communication to a host computer. A Stewart Connector Systems Inc. SS-641010S-A-NF may serve as connector  36  for mating with a Stewart Connector 937-SP-361010-031 matching connector of a host device. Host interface  18  may also comprise a Molex MX52588 connector. Regardless of the type of connector  36  used, host transceiver  34  is programmed with the applicable protocols for interfacing with a host computer, such as USB, Bluetooth(r), and IrDA protocols. Transceiver  34  may also be programmed to support both non-inverted signal sense and inverted signal sense. 
     Microcontroller  12  comprises a conventional programmable microprocessor having on-chip peripherals, such as central processing unit, Flash EEPROM, RAM, asynchronous serial communications interface modules, serial peripheral interfaces, Inter-IC Buses, timer modules, pulse modulators with fault protection modules, pulse width modulators, analog-to-digital converters, and digital-to-analog converters. Additionally, the inclusion of a PLL circuit allows power consumption and performance to be adjusted to suit operational requirements. In addition to the I/O ports dedicated I/O port bits may be provided. Microcontroller  12  may further include an on-chip bandgap based voltage regulator that generates an internal digital supply voltage from an external supply range. Microcontroller  12  preferably comprises a Motorola MC9S12E128. 
     The functional integration of imager  14  and RFID unit  16  to interface  18  is accomplished by microcontroller  12 , which receives and interprets host commands, and then executes the appropriate functions by driving imager  14  and/or RFID unit  16  accordingly. For example, the operation of imager  14  and RFID unit  16  may be triggered by serial commands sent to module  10  from a host device  38 , or by a hardware button communicating directly with connector  36  or through host device  38 . Microcontroller  12  may further be programmed to execute the functions otherwise performed by one or more of image engine  20 , RFID transceiver  30 , and host transceiver  34 , thereby reducing the amount of circuitry and hardware required by module  10 . 
     When integrating imager  14  and RFID unit  16 , module  10  has three principle operational modes: image scanning using imager  14 , tag interrogation using RFID unit  16 , an interleaved mode that is a combination thereof, and a simultaneous mode. In imaging-only mode, module  10  will image and perform the applicable algorithms, such as barcode deciphering, until a barcode is detected or the device is un-triggered. In RFID-only, module  10  will interrogate until a tag is successfully read or module  10  is un-triggered. In interleaved mode, module  10  toggles between imaging and interrogation according to a predetermined timeout schedule. In simultaneous mode, module  10  causes simultaneous imaging and interrogation. In addition, module  10  may be programmed with timeouts to prevent hang-ups. As module  10  can receive, interpret, and execute host commands, these modes may be controlled by a user from host device  38 . 
     Microcontroller  12  may direct RFID interrogation using RFID unit  16  in at least two modes. RFID unit  16  may operate in a free form mode that reads and writes data as a continuous stream, which is limited only by memory capacity. Once RFID unit  16  is triggered, depending on the mode, data is emitted from the serial port. Second, RFID unit  16  may operate in block mode, where a user may access individual blocks of information via commands sent through interface  18  and interpreted by microcontroller  12 . 
     External control of module  10  is accomplished by a predefined protocol and set of serial host commands that are sent to module  10  from host device  38 . The host commands are received by microcontroller  12 , which executes the appropriate steps based on the content of the host command. For example, microcontroller  12  may be programmed to recognize host commands that trigger the activation of imager  14  and/or RFID unit  16 . Host commands may also be defined to whether the data obtained from imager  14  and/or RFID unit  16  is stored locally in module  10  or passed through interface  18  to host device  38 . Host commands may also be provided that enable the various scanning or imaging modes available from imager  14  and RFID unit  16 , control the amount of time that imager  14  and RFID unit  16  will attempt scanning before timing out, direct the reading and writing of image and scan data, and select the location where the data is to be written. With regard to imager  14  and RFID unit  16 , commands for opening and closing connections to image engine  20  and RFID transceiver  30 , as well as commands that return the status of the connection are useful. For example, a host command received from host device  38  may trigger the capture of barcode or RFID data from imager  14  or RFID unit  16 . When the scan is complete, a timeout occurs or triggering is turned off via a second host command, and the appropriate feedback is provided to host device  38 . The host commands may be preprogrammed into microprocessor  12  and separately provided to host device  38  as a software package for controlling module  10 . In addition, software for editing host commands may be supplied to host device  38  to allow a user to edit, add, or delete commands and the corresponding functionality. 
       FIG. 3  illustrates an embodiment of main-line host command processing in microprocessor  12  according to the present invention. The specific nomenclature used to define the various routines may be varied by the user or software developer provided that the appropriate functions are performed, and any number of routines and subroutines may be defined and executed in various orders to accomplish image and RFID reading and processing according to the present invention. After initialization  40 , microcontroller  12  runs a routine, referred to as GetHostCommand  42 , to check whether a host command has been received from host device  38 . Upon receipt of a host command, microprocessor  12  checks whether the command is an RFID control command, CMD_RFID  44 . If so, the command is processed by routine ProcessRFID_Command  46 . If not, a check is performed to see whether the command is an trigger command, CMD_TRIGGER  48 . If the command is a trigger command, the appropriate instruction are processed to initiate triggering, InitTriggerProcessing  50  and a variable, referred to as CurrentlyTriggered  52 , is assigned the value of TRUE or FALSE depending on whether the selected device has already been triggered. If the command is not a trigger command, a check is performed to see whether the command is an untrigger command, CMD_UNTRIGGER  54 . If the command is an untrigger command, the appropriate steps are taken to stop triggering, UnTriggerImager  56 , and a variable, CurrentlyTriggered  58 , is assigned the value of TRUE or FALSE depending on whether the selected device has already been triggered. 
     After any of the above processing, microprocessor  12  checks to see whether a hardware trigger has been pressed  60 , the triggering processing is performed, InitTriggerProcessing  62 , and a variable, referred to as CurrentlyTriggered  64 , is assigned the value of TRUE or FALSE depending on whether the selected device has already been triggered. If a hardware trigger has not been pressed  60 , the appropriate instruction are processed to stop triggering, UnTriggerImager  66 , and a variable, referred to as CurrentlyTriggered  68 , is assigned the value of TRUE or FALSE depending on whether the selected device has already been triggered. Finally, microprocessor checks to see whether the CurrentlyTriggered variable is TRUE or FALSE  70 , and then calls function Trigger  72  or function UnTrigger  74  as appropriate. Data is then read from imager  14  and written to the host, ImagerReadAllHostWrite  76 , and host data that should be routed to imager  14  is written to it, FifoGetAllDataImagerWrite  78 . 
     There is seen in  FIGS. 4A and 4B , trigger host command processing in microprocessor  12  according to the present invention. Upon receipt of a trigger command, microcontroller  12  first checks to see whether barcode only scanning  80 , RFID only scanning  82 , interleaved RFID and barcode scanning  84 , or simultaneous RFID and image scanning  86  has been previously selected. If bar code only scanning  80  has been selected for the first time  88 , and since InitTriggerProcessing  50  has been called, microcontroller  12  triggers imaging  90 . If an image is successfully captured and applicable information successfully extracted from the image  92 , such as barcode, microcontroller  12  assigns FALSE to the variable CurrentlyTriggered  94 . If RFID only scanning  82  has been selected, microcontroller  12  turns the RFID transmitter on  94 . If an RFID tag is successfully read  96 , an audible tone is sounded and microcontroller  12  sets variable CurrentlyTriggered to FALSE  98 . Microcontroller  12  turns transmitter off  100 . If interleaved RFID and barcode scanning  84  has been selected, microcontroller  12  toggles operation of imager  14  and RFID unit  16  using a timer  102 . If simultaneous RFID and image scanning  86  has been selected, microcontroller  12  checks to see whether the triggering is for the first time  104  and, if so, triggers the imager  106 . Transmission from the RFID unit  16  is also turned on  108 , and a nearby RFID tag is read  110 . If the reading of tag  110  is successful, an audible tone is sounded and variable CurrentlyTriggered is set to FALSE  112 . Imager  14  is also untriggered  114  and the transmitter is turned off  116 . If the image is successfully processed, e.g., a barcode is received  118 , and variable CurrentlyTriggered is set to FALSE  120 . 
     There is seen in  FIG. 5 , an infusion pump  130  comprising a display screen  132  for visually presenting status or programming information and a keypad  134  or keyboard associated therewith for manual entry of data by medical personnel. Infusion pump  130  controls the delivery of fluid medication from an intravenous bag  136  through tubing  138  to a patient (not shown). Infusion pump  130  further comprises a microcontroller  140  for controlling the various operations and functionality of infusion pump  130 . Infusion pump  130  also comprises a combined RFID and imaging module  10  associated therewith. Preferably, module  10  is provided within pump  130  and interconnected to microcontroller  140  via a connector  142  that mates with connector  36  of host interface  18 . Thus, microcontroller  140  of pump  130  acts as a host device, as explained above, and is programmed to provide host commands to module  10 , thereby controlling operation of optical imager  14  and RFID unit  16 . Module  10  is positioned within pump  130  so that imager  14  is flush with the housing of pump  130 , or so that all or a portion of imager  14  extends outwardly from pump  130 , such that object may be presented to imager  14  and one or images thereof may captured by imager  14 . 
     Imager  14  may capture and decode barcode information contained on IV bag  136 , a badge  144 , or even a patient wristband  146 . As module  10  also includes RFID unit  16 , information may be additionally stored on IV bag  136 , badge  144 , and patient wristband  146  for interrogation by RFID unit  16 . Thus, infusion pump  130  may be automatically provided with all of the information necessary to safely and securely verify that the proper medication is being given to the patient in the appropriate, prescribed dosages and rates. 
     A sample control process  150  for pump  130  is illustrated in  FIG. 6 . More particularly, infusion pump  130  is first activated  152  by a medical worker, such as by turning on infusion pump  130 . Next, the form of data retrieval is selected  154 , e.g., optical imaging/barcode and/or RFID. The format may be preprogrammed into microcontroller  140 , or manually selected by use of keypad  134 . After selection  154 , the appropriate host command is sent  156  to module  10  by microcontroller  140 . As described above, host commands controlling operation of module  10  may be supplied to a host device, such as infusion pump  130 , as software that is loadable onto microcontroller  140 . Next, data is acquired according to the host command  158  using imager  14  or RFID unit  16 . Successfully acquired data is then provided  160  by module  10  to infusion pump  130  via host interface  18  to microcontroller  140  using the appropriate protocols. If any additional data is to be automatically provided to infusion pump  130 , steps  154 - 160  may be repeated for each object from which data is to be acquired. Microcontroller  140  then verifies that delivery is proper  162  by considering the data acquired by module  10 , and infusion pump  130  is enabled for delivery of medication to the patient. 
     Verification of delivery  162  encompasses any number of checks. For example, microcontroller  140  may receive information about the particular medicine to be dispensed from bag  136 , about the individual who is authorizing the delivery of the medicine from badge  144 , and about the patient who will be receiving the medication from wristband  146 , whether by capturing optical images of identification objects containing indicia, such as barcodes, or data stored within identification objects, such as RFID tags. Microcontroller  140  may then retrieve the patient&#39;s electronic medical records from the hospital&#39;s electronic medical records database, whether copied and stored locally or accessed remotely through a hospital-wide network, and compare the stored information with the acquired information to ensure that the IV medications were actually ordered for the patient, and to confirm when the patient is scheduled to receive the medication. Microcontroller  140  can also verify the identity of the medical worker who is activating the infusion pump to ensure that the person is authorized to dispense the particular medication. Microcontroller  140  can further cross-check the prescribed dosage for the particular medication against stored medical records containing the proper dosages and infusion rates for particular medications. Only after some or all of these checks are performed will infusion pump  130  be enabled  164  to deliver medicine to the patient.