as) United States
`a2) Patent Application Publication 10) Pub. No.: US 2009/0275810 Al
`
`(43) Pub. Date: Nov.5, 2009
`Ayersetal.
`
`US 20090275810A1
`
`(54)
`
`PORTABLE MODULARPC BASED SYSTEM
`FOR CONTINUOUS MONITORING OF
`BLOOD OXYGENATION AND RESPIRATORY
`PARAMETERS
`
`(75)
`
`Inventors:
`
`Eric J. Ayers, Alliquippa, PA (US);
`Eric W. Starr, Allison Park, PA
`(US)
`
`Correspondence Address:
`BLYNNL. SHIDELER
`THE BLK LAW GROUP
`3500 BROKKTREE ROAD, SUITE 200
`WEXFORD,PA 15090 (US)
`
`(73)
`
`Assignee:
`
`STARRLife Sciences Corp.,
`Oakmont, PA (US)
`
`(21)
`
`Appl. No.:
`
`12/485,902
`
`(22)
`
`Filed:
`
`Jun. 16, 2009
`
`Related U.S. Application Data
`
`(63) Continuation-in-part of application No. 12/434,599,
`filed on May 1, 2009.
`
`(60) Provisional application No. 61/073,003, filed on Jun.
`16, 2008, provisional application No. 61/049,451,
`filed on May 1, 2008.
`Publication Classification
`
`(51)
`
`Int. Cl.
`(2006.01)
`AGIB 5/00
`(2006.01)
`GO8B 23/00
`(52) US. C0e oecccccssecsssssssssssssenneeseeseee 600/301; 340/573.1
`
`(57)
`
`ABSTRACT
`
`A portable modular kiosk based physiologic sensor system
`for clinical and research applications configured to simulta-
`neously utilize multiple sensors with cross checking and
`cross calculation of physiologic parameters and configured
`for continuous monitoring of blood oxygenation andrespira-
`tory parameters.
`
`APPLE 1010
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`Patent Application Publication
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`PRIOR ART
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`Patent Application Publication
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`Nov. 5, 2009 Sheet 3 of 3
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`RELATED APPLICATIONS
`
`PORTABLE MODULARPC BASED SYSTEM
`from a computer network. Some common computer kiosks
`FOR CONTINUOUS MONITORING OF
`provideafree, informational public service while others com-
`BLOOD OXYGENATION AND RESPIRATORY
`mon computer kiosks serve a commercial purpose. Touch-
`PARAMETERS
`screens, trackballs, computer keyboards, and pushbuttonsare
`all typical input devices for interactive computer kiosk.
`[0010] The “personal computer” or simply “PC”is a term
`that is so often used it seemsunlikely,atfirst, to require formal
`definition. However the precise scope of the term is some-
`times vague. A PC is a computer whosesize, and capabilities
`(and somehavesaid price) make it useful for individuals,
`intendedto be operated directly by an end user and capable of
`performinga variety of general purpose tasks, with no inter-
`vening computer operator. The PC may be a home computer,
`or may be foundin an office, a medical facility or a research
`lab. The PC mayoften be connected to a local area network.
`The distinguishing characteristics of a PC are that the com-
`puteris primarily used, interactively, by one personat a time.
`This is opposite to the batch processing or time-sharing mod-
`els which allowed large expensive systems to be used by
`many people, usually at the same time, or large data process-
`ing systems which required a full-time staff to operate. The
`PC can come in desktop models, notebook models, handheld
`models, and hybrids of these.
`[0011] A “notebook computer’, or simply “notebook”
`within this application, is an extremely lightweight PC. Note-
`book computers typically weigh less than 6 pounds and are
`small enough tofit easily in a briefcase. Aside from size and
`portability, the principal difference between a notebook com-
`puter and a non-notebook personal computer(e.g. a desktop
`computer) is the display screen. Notebook computers use a
`variety of techniques, known asflat-pane technologies, to
`produce a lightweight and non-bulky display screen. Laptop
`computers and tablet PCs are two types of notebook comput-
`ers. Usually all of the interface hardware needed to operate
`the notebook computer, such as parallel and serial ports,
`graphics card, sound channel, etc., are built in to a single unit.
`Most notebook computers contain batteries to facilitate
`operation without a readily available electrical outlet.
`[0012] A “laptop computer”, or simply laptop, is, within
`this application, a subset of notebooks. A laptop will have a
`display and separate keyboard interface (e.g. “qwerty” key-
`board), with the keyboard and the display typically hinged
`together. The term Laptop is sometimes used more broadly
`and equated with notebooks, but the term will have a narrower
`definition within this application.
`[0013] A “Tablet PC” is a notebook, also called a panel
`computer, and wasfirst introduced by Pen Computing in the
`early 90s with their PenGo Tablet Computer and popularized
`by Microsoft. The touch-screen or “graphics tablet/screen
`hybrid technology”technology of the tablet PHOTOCHRO-
`MICallowsthe user to operate the computer with a stylus or
`digital pen, or a fingertip, instead of a keyboard or mouse. The
`tablet PC is particularly well suited to operate in Kiosk mode
`in light of the built in user interface provided with the tablet
`PC.
`
`[0001] The present application claims the benefit of U.S.
`Provisional Patent Application Ser. No. 61/073,003 entitled
`“Apparatus for Continuous Monitoring of Blood Oxygen-
`ation and Respiratory Parameters”filed Jun. 16, 2008.
`[0002] The present application is a continuation in part of
`USS. patent application Ser. No. 12/434,599 entitled “Por-
`table Modular Kiosk Based Physiologic Sensor System with
`Display and Data Storage for Clinical and Research Applica-
`tions including Cross Calculating and Cross Checked Physi-
`ologic Parameters Based Upon Combined SensorInput”filed
`May 1, 2009.
`[0003] U.S. patent application Ser. No. 12/434,599 claims
`the benefit of U.S. Provisional Patent Application Ser. No.
`61/049,451 entitled “Portable Modular Kiosk Based Physi-
`ologic Sensor System for Clinical and Research Applications
`Configured to Simultaneously Utilize Multiple Sensors with
`Cross Checking and Cross Calculation ofPhysiologic Param-
`eters”filed May 1, 2008.
`
`BACKGROUND OF THE INVENTION
`
`1. Field of the Invention
`[0004]
`[0005] The present invention relates to a portable, modular
`physiologic sensor system with display and data storage for
`clinical and research applications, in particular to small mam-
`mal applications, such as neonates in humansand rats and
`mice in research applications, for continuous monitoring of
`blood oxygenation and respiratory parameters.
`[0006]
`2. Background Information
`[0007] The present
`invention relates to monitoring of
`physiologic parameters ofa patient or subject, in particular an
`animal patient or subject, such as a small mammal, such as
`neonates in humans and rats and mice in research applica-
`tions. The following definitions will be helpful in explaining
`the known background elements that are helpful for under-
`standing the present invention. Physiologic parameters are
`measured with physiologic sensors that typically, but not
`always, contact the patient or subject. The term patient is
`appropriate in the medical fields for both the human medical
`field and animalveterinarian fields. The term subject is appro-
`priate in the researchfield, and the term subject will apply to
`human and non-human applications.
`[0008] The list of physiologic sensors is large and con-
`stantly growing. A representative list of physiologic sensors
`knownin the art include blood pressure sensors, blood flow
`sensors, blood glucose sensors, blood cholesterol sensors,
`heart sound sensors, EMG sensors, EEG sensors, EKG sen-
`sors, EOGsensors, pulse sensors, oxygenation sensors, blood
`perfusion sensors, respiration monitors, temperature sensors,
`blood gas sensors, motion sensors, strain gauges, body posi-
`tion sensors, and limb motion sensors.
`[0009] A “kiosk’ within this application, sometimescalled
`an electronic kiosk, computer kiosk or interactive kiosk,
`houses a computer terminal that often employs custom kiosk
`software designed to function, hopefully flawlessly, while
`preventing users from accessing system functions. “Kiosk
`mode”is a euphemism for sucha modeof software operation.
`Computerized kiosks may store data locally, or retrieve it
`
`[0014] The input/output ports of a personal computer refer
`to the communicationslinks through whichthe personal com-
`puters send andreceive information, which generally include
`serial ports, parallel ports, wireless links or connectors (such
`as WI-FL and Bluetooth), and universal serial bus (USB)
`ports. In addition, some laptops have expansion slots for
`PCMCIAstandard adaptor cards (Type 1 and Type II)that also
`form input/outputports.
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`Intheclinicalfields, physiologic parameters of sub-
`[0015]
`jects are typically viewed through a “medical monitor”thatis
`defined as an automated medical device that sensesa patient’s
`vital signs through an associated sensor and displays the
`results. Medical monitorsare typically highly specialized and
`suited solely for the designated monitoring tasks. The modern
`trend is to have multi-parameter medical monitors that can
`track and display different vital signs on a commondisplay.
`This specialization has limited the applicability of many of
`these devices in the research applications. Further, this spe-
`cialization has, in some applications, limited the portability of
`the medical monitor, limiting the applications to the hospital
`or clinic environment and resulting in the device being
`impractical for certain portable applications such as needed in
`the veterinary fields.
`[0016]
`Inthe researchfield, physiologic parameters of sub-
`jects can, of course, be viewed through a “medical monitor”
`in the same manneras in currentclinical fields. The assignee
`of this application has developed laptop and desktop PC
`based physiologic sensors that have been embraced by
`researchers. These devices, such as the MOUSE OX™brand
`pulse oximeters, allow researchers to collect data on the
`physiologic parameters of the subjects such as mice on the
`researcher’s laptop or desktop PC and to work with the data
`on their laptop or desktop PC. These laptop and desktop PC
`based physiologic sensor systems could, in theory, be oper-
`ated in the clinical environments. However, the current laptop
`and desktop PC based physiologic sensor systems have not
`been widely adoptedin theclinical fields because (1) there is
`a more significant space restriction associated with many
`clinical applications (i.e. there is no available desktop space
`and thus the system would require its own cart or stand), and
`(2) there is a need in clinical environments to avoid the pro-
`gram start up and selection procedures associated with gen-
`eral operating PCsas clinical technician are less inclined to
`work through an operating system to view and/or record the
`physiologic parameters.
`[0017] A physiologic sensor within the meaning ofthis
`specification is a sensor that measures a parameterrelated to
`a physical characteristic of a living subject, such as a human
`or animal. The types of physiologic sensors include, for
`example, blood pressure sensors, blood flow sensors, blood
`glucose sensors, blood cholesterol sensors, heart sound sen-
`sors, EMG sensors, EEG sensors, EKG sensors, EOG sen-
`sors, pulse sensors, oxygenation sensors, pulse-oximetry sen-
`sors, blood perfusion sensors,
`respiration sensors (both
`pressure,
`flow and rate),
`temperature sensors, additional
`blood gas sensors (such as nitrogen partial pressure, carbon
`dioxide partial pressure, carbon monoxidepartial pressure,
`oxygenpartial pressure, and pH level), motion sensors, strain
`gauges, body position sensors, limb motion sensors and the
`like.
`
`[0018] Respiratory sensors are a subset of physiologic sen-
`sors and refer to those sensors primarily measuring physical
`parameters ofa subject indicative ofrespiration ofthe subject.
`A ventilation based sensoris, for example, a respiratory sen-
`sor. Cardiac sensors are a subset of physiologic sensors and
`refer to those sensors primarily measuring physical param-
`eters of a subject indicative of cardiac function of the subject.
`A pulse oximeteris, for example, a cardiac sensor. However,
`as noted in detail below, a respiratory sensor can provide
`signals indicative of other physiologic parameters outside of
`respiration and a cardiac sensor can provide signals indicative
`
`ofnon-cardiac functions. For example the pulse oximeter can
`be used to calculate breathingrates.
`[0019] U.S. Published Patent Application 2006-0264762
`discloses a personal computer (PC) based physiologic moni-
`tor system that includes a personal computer having a display
`and an input/output port for attachmentto an external device.
`The PC based system also includes a physiologic sensor
`coupled to the personal computer through the input/output
`port so that a modified output of the physiologic sensoris
`graphically displayed on thedisplay. A controller, a portion of
`which is disposed in the personal computer, modifies the
`output of the physiologic sensor and provides a feedback
`control signal for modifying the output of the physiologic
`sensor. This disclosure is incorporated herein by reference,
`portions of which are repeated below for convenience.
`[0020]
`FIG. 1isaschematicpriorart respiratory system 10
`for outpatient surgery of U.S. Published Patent Application
`2006-0264762. Three common systems for supplying seda-
`tion anesthesiato the patient 12 include an intravenous supply
`system for anesthesia such as shownin FIG.1, a respiratory
`system coupled to the patient, such as shown in FIG. 2, and
`needle and syringe injection (not shown). In the intravenous
`supply system of FIG. 1 the sedentary aesthesia is provided in
`an appropriate solution in an I.V. bag 14 on a conventional
`stand 16. As noted, a needle and syringe could also be used to
`supply intravenous sedentary anesthesia to the patient 12
`through simple, periodic injections. The respiratory system
`10 of U.S. Published Patent Application 2006-0264762
`includesa ventilatory system coupledto a patient 12. Specifi-
`cally the ventilatory system has a controlled blower motor 20,
`having a respiratory gas intake and power supply (not shown)
`and a respiratory gas output coupledto the patient 12 through
`tubing 22 and mask 24. The mask 24 may be replaced by nasal
`canella or other respiratory patient couplings as desired. The
`mask 24 or tubing 22 includes a vent 26 for a patients exhal-
`ing, as generally knownin the art. The respiratory system 10
`includesa respiratory sensor 28 coupled to the patient 12 and
`adapted to detect a respiration parameterof the patient 12. In
`FIG.1 the sensor 28 is attached to the patient 12 through the
`tubing 22, and in this configuration it may be a pressure or
`flow sensor for detecting the respiration parameters of the
`patient 12. The sensor 28 could be placed on the mask 24, at
`the vent 26, or even on the blower motor20, and obtain signals
`indicative of the patient’s respiration parameters. The sensor
`28 may be placed directly on the patient 12 as well. The
`specific type and the location of the sensor 28 can vary,
`providedthat the sensor provides an output indicative of the
`patient’s respiration parameters(i.e. at least the time of and
`preferably an indication of how muchrespiratory volume the
`patient is receiving with each breath). In the respiratory sys-
`tem 10 the blower motor 20 and the respiratory sensor 28 are
`coupledto a central controllerthat is in the form of a lap-top
`computer 30. The sensor 28 is coupled to the computer 30
`through an amplifier 32 to prove a meaningful signal to the
`computer 30. The coupling between the amplifier 32 and the
`computer 30, shownas link 34, may be a hardwire connection
`or a wireless connection. In a similar fashion, the coupling
`between the blower motor 20 and the computer 30, shown as
`link 36, may be a hardwire connection or a wireless connec-
`tion. Where the links 34 are hardwire connections, it is pre-
`ferred that they couple to conventional existing ports of the
`laptop computer 30. The respiratory system 10 additionally
`includesfurther physiologic sensors coupled to the patient 12.
`Specifically a pulse oximeter sensor 40 is attached to the
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`patient 12 and coupled to the computer 30 through an ampli-
`fier 42 and link 44. The link 44 between the amplifier 42 and
`the computer 30, shown discussed above, may also be a
`hardwire connection or a wireless connection. The addition of
`
`physiologic sensors, such as sensors 28 and 40, allows the
`computer to be a physiologic monitor graphically displaying
`the sensed parameters of the patient, as will be described in
`detail hereinafter. The sensors for this physiologic monitor
`are notlimited to respiratory, pulse and blood oxygenation as
`shown in FIGS. 1 and 2, but may further include a blood
`pressure sensor, a blood flow sensor, a blood glucose sensor,
`a blood cholesterol sensor, a heart sound sensor, an EMG
`sensor, an EEG sensor, an EKG sensor, an EOG sensor, a
`blood perfusion sensor, a temperature sensor, a blood gas
`sensor, a motion sensor, a strain gauge, a body position sen-
`sor, a limb motion sensor, and any combinationsthereof.
`[0021] The respiratory system 10' of FIG. 2 is similar to
`system 10 of FIG. 1 and is also described U.S. Published
`Patent Application 2006-0264762. Prior art FIG. 2 differs in
`the system for supplying sedation anesthesia to the patient 12.
`Inhaled anesthesia agents are used in the embodimentof FIG.
`2, which are supplied to the blower motor 20 through anes-
`thesia gas supply 50 and input 52. Whenusing inhaled agents
`for anesthesia the ventilatory system cannotventto the room,
`or it could adversely affect the caregivers. Therefore a closed
`system is created where vent 26 is replaced with a one way T
`coupling 26' leading, through tubing 54, to a CO,/anesthesia
`scrubber 56 that can vent harmless material or return the
`
`scrubbedrespiratory gassesto the input 52 through tubing 58.
`A source of oxygen 60 is coupled to the input 52 through
`tubing 62 to supply oxygento the closed system. An oxygen
`sensor 64 may be provided on input 52 (or else ware on the
`closed system) and coupledto the controller 30 through link
`66. The link 66 between the sensor 64 (which may have an
`amplifier—not shown) and the computer 30, shown discussed
`above, mayalso be a hardwire connection or a wireless con-
`nection. As aclosed respiratory system it is importantto track
`the oxygen level received by the patient 12.
`[0022] There remains a need in the art to for a simple to
`simple to use physiologic sensor system effective for clinical
`and research applications.
`
`SUMMARYOF THE INVENTION
`
`Some of the above objects are achieved with a por-
`[0023]
`table modular kiosk based physiologic sensor system for
`clinical and research applications configured to simulta-
`neously utilize multiple sensors with cross checking and
`cross calculation of physiologic parameters.
`[0024] The term “cross calculating” within the meaning of
`this application references the calculation of a physiologic
`parameter in which the input from at least two sensorsthat are
`coupled to two distinct standard input ports on the PC are
`utilized in the calculation of the parameter.
`[0025] The term “cross checking” within the meaning of
`this application references the calculation of a physiologic
`parameter in which the input from at least two sensorsthat are
`coupled to two distinct standard input ports on the PC are
`utilized independently in the separate calculation of the
`parameter and these two valuesare utilized to arriveat a given
`parameter value.
`[0026] One advantage of the present invention is that one
`embodiment permits the continuous monitoring of blood
`oxygenation and respiratory parameters particularly in small
`mammals.
`
`[0027] These and other advantages ofthe present invention
`will be clarified in the description of the preferred embodi-
`ments taken together with the attached drawingsin which like
`reference numerals represent like elements throughout.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 is a schematic view of a respiratory system
`[0028]
`for outpatient surgery performed under sedation level anes-
`thesia according to a prior art system as described in U.S.
`Published Patent Application 2006-0264762;
`[0029]
`FIG. 2 is a schematic view of a respiratory system
`for outpatient surgery performed under sedation level anes-
`thesia according to a prior art system as described in U.S.
`Published Patent Application 2006-0264762;
`[0030]
`FIG. 3 is a schematic view of a portable modular
`kiosk based physiologic sensor system for clinical and
`research applications configured to simultaneously utilize
`multiple sensors with cross checking and cross calculation of
`physiologic parameters in accordance with the present inven-
`tion;
`FIG. 4 is a schematic section view of tablet com-
`[0031]
`puter sample display of the portable modular kiosk based
`physiologic sensor system according to one aspect of the
`present invention;
`[0032]
`FIG. 5 is a schematic view of a portable modular
`kiosk based physiologic sensor system for clinical and
`research applications configured to simultaneously utilize
`multiple sensors with cross checking and cross calculation of
`physiologic parameters in accordance with the present inven-
`tion;
`FIG. 6 is a schematic view of another portable
`[0033]
`modular PC based physiologic sensor system for clinical and
`research applications configured to simultaneously utilize
`multiple sensors with cross checking and cross calculation of
`physiologic parameters in accordance with the present inven-
`tion; and
`FIG. 7isa schematic view of a portable modular PC
`[0034]
`based physiologic sensor system for clinical and research
`applications configured to simultaneously utilize permits the
`continuous monitoring of blood oxygenation andrespiratory
`parametersparticularly in small mammals in accordance with
`the present invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`FIG. 3 is a schematic view of a portable modular
`[0035]
`kiosk based physiologic sensor system 110 for clinical and
`research applications configured to simultaneously utilize
`multiple sensors 112 with cross checking and cross calcula-
`tion ofphysiologic parameters in accordance with the present
`invention.
`
`[0036] One key componentofthe present invention is a PC
`computer 114 to which the multiple sensors 112 can be
`attached through conventional PC input ports 116. As noted
`abovethe input/output ports 116 of a personal computer 114
`refer to the communicationslinks through whichthe personal
`computers 114 send and receive information, which generally
`include serial ports, parallel ports, wireless links or connec-
`tors (such as WI-FL and Bluetooth), and universal serial bus
`(USB) ports 116. Where a physical connection is used(i.e.
`non-wireless), the USB port 116 will be the preferred con-
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`nection for the present invention as several such input ports
`116 are commonly provided on commercially available PC
`Computers 114.
`[0037] The PC computer 114 of the present invention is
`preferably a notebook computer 114 such as a tablet PC 114
`as shown in FIGS. 3 and 5. As noted above a notebook
`computer 114 is an extremely lightweight PC that typically
`weighs less than six (6) pounds and is small enoughto fit
`easily ina briefcase. Laptop computers andtablet PCs 114 are
`two types of notebook computers 114 for use in the present
`invention, wherein all of the interface hardware needed to
`operate the notebook computer 114, such as parallel and
`serial ports, graphics card, sound channel,etc., are built in to
`a single unit. The notebook computers 114 for implementing
`the present invention contain batteriesto facilitate operation
`withouta readily available electrical outlet.
`[0038]
`In one embodimentofthe presentinvention the sys-
`tem 110 according to the present invention is designed pri-
`marily for clinical applications. In the clinical application of
`the present invention the PC 114is in the form of a Tablet PC
`114, also called a panel computer, that incorporates a touch-
`screen 130 or “graphics tablet/screen hybrid technology”
`technologythat allows the user to operate the computer with
`astylusor digital pen 122, ora fingertip, instead ofa keyboard
`or mouse. A joystick may be incorporatedinto the tablet 14 as
`a separate user input device.
`[0039]
`In the clinical application of the present invention
`the Tablet PC 114 is operated in Kiosk mode. The Tablet PC
`114 is particularly well suited to operate in Kiosk mode in
`light of the built in user interface provided with the tablet PC
`114. One simple methodof operating in Kiosk mode with the
`Tablet PC 114 is for the operating software to be launchedat
`system start up. In a Microsoft Window® environmentthis is
`easily accomplished by dragging the operating software into
`the startup menu wherebyit will be launched automatically at
`system startup. In this mannerthe system 110 is operable with
`simply a push ofthe on-off button.
`[0040] One critical componentof the present invention is a
`series of physiologic sensors 112 that are configured to be
`coupled to an input port 116 of the PC 14 such as through a
`USBport or through a wireless connection 118. Each sensor
`112 is configured to measure a parameterrelated to a physical
`characteristic of a living subject, such as a human or animal,
`in particular a small mammal such as a mouse.
`[0041] The types of physiologic sensors 112 include, for
`example, blood pressure sensors 112, blood flow sensors 112,
`blood glucose sensors 112, blood cholesterol sensors 112,
`heart sound sensors 112, EMG sensors 112, EEG sensors 112,
`EKGsensors 112, EOGsensors 112, pulse sensors 112, oxy-
`genation sensors 112, pulse-oximetry sensors 112, blood per-
`fusion sensors 112, respiration sensors (both pressure, flow
`and rate) 112, temperature sensors 112, additional blood gas
`sensors (such as nitrogen partial pressure, carbon dioxide
`partial pressure, carbon monoxide partial pressure, oxygen
`partial pressure, and pH level) 112, motion sensors 112, strain
`gauges 112, body position sensors 112, limb motion sensors
`112 andthelike.
`
`For example, the MouseOx® sensor sold by the
`[0042]
`assignee of the present
`invention is one representative
`example ofa sensor 112 for use in the system according to the
`present invention.
`[0043] The sensors 112 will typically include an analog to
`digital converter (shown in coupling 118) between the sensor
`112 elements that are coupled to the subject 120 and the PC
`
`coupling or port 116. Additionally the sensors 112 will occa-
`sionally need power. The sensors 112 may be pluggedinto a
`powersupply through a separate power cord. However, in one
`aspectofthe present invention separate power supplyis incor-
`porated into the sensor 112 to allow for elimination of the
`external power coupling and the needfor a “close by” source
`of power, allowing the system to be particularly well suited
`for “field” operation. A separate method of eliminating the
`external power supply in the sensors 112 is to design the
`sensors 112 to draw power from the PC 114 through the
`coupling 118 to the PC 114. The elimination of the external
`powersupply on the sensors 112 will assist in the portability
`of the system 110.
`[0044] The modular aspect ofthe system 110 in accordance
`with the present inventionis that a plurality of sensors 112 is
`provided for use in the system 110. It is anticipated that the
`user(clinician or researcher) will utilize a plurality of sensors
`112 at the same time for any given subject 120 as shown in
`FIGS. 3 and 5. It is expected that these sensors 112 can be
`easily plugged into and removed from the PC 114. The PC
`114 of the system 110 will recognize which sensors 112 are
`coupledto the input ports 116 and will configure the display
`130 to display all of the relevant parameters at a designated
`display 132. The particular designated parameters display
`132 that are calculated by the collection of sensors 112
`(whether the parameters are calculated by individual sensors
`112, cross checked with multiple sensors 112 or cross calcu-
`lated from the output oftwo or more sensors 112). The display
`130 can also include touch screen “buttons”or controls 134
`for operation of the system 110.
`[0045] Another aspect of the system 110 of the present
`invention is the cross checking of physiologic parameters
`determined by the system 110. In other words, for cross
`checking of a parameter, the calculation of the physiologic
`parameteruses the input from at least two sensors 112 that are
`coupled to two distinct standard input ports 116 on the PC 114
`wherein these inputs are utilized independently in the sepa-
`rate calculation of the parameter and these two values are
`utilized to arrive at a given parametervalue.
`[0046] The concept of cross checking may be explained
`better by way of example. Breath rate of a subject 120 can be
`determined by both a ventilation based pressure sensor 112
`and from a pulse oximeter 112. In this examplethe ventilation
`based sensor 112 is a respiratory sensor andthe pulse oxime-
`ter is a cardiac sensor 112. Regardless the breath rate can be
`calculated by both sensors 112 independently and the Cross
`checking will use these two values in somefashion.
`[0047] The use rules for cross checking may be that the
`dominant measurement rules. For example, the ventilation
`based sensor 112 can be considered a more accurate and
`robust measurement for this particular parameter, whereby
`the cross checking operates by having this be the dominant
`value. In other words if the ventilation based sensor 112
`
`calculates the respiratory rate with a high degree of confi-
`dencethen this is the valuethat is reported for this parameter
`and the pulse oximeter 112 reading or breath rate calculation
`is used if the respiratory sensor is not a confident reading.
`Further, the dominant reading can be comparedto the less
`dominantreading andif there is a difference then the system
`can record that their may be an error in the non-dominant
`sensor. This can be important information since if the pulse
`oximeter is way off in the calculation of the breath rate then
`other readings may also be suspect. This cross checking sys-
`tem can thus be used as a sensor checking feature.
`
`8
`
`

`

`US 2009/0275810 Al
`
`Nov. 5, 2009
`
`[0048] The use rules for cross checking may be an averag-
`ing of two calculated valuesto obtain a final parameter value,
`together with a checking ofhowfar apart the two independent
`values are. The greater the variance in the independently
`obtained values the less confidence the system 110 should
`have in the accuracy of the final value. A threshold for the
`amount of difference that is acceptable can be utilized for
`each particular cross checked parameter.
`[0049] Theuserules for cross checking may include the use
`of threshold values and a discarding of those independently
`calculated parameter values that are outside the threshold. If
`both calculated parameters are outside the threshold then the
`system 110 can indicate that no value was calculated, or the
`system 110 may use the last known calculated parameter to
`display. If both calculated parameters are outside the thresh-
`old then the system 110 can further use one of the systems or
`methodologies described above such as averaging or domi-
`nant sensorrules.
`
`[0050] The cross checking may be associated with more
`than two sensors 112, but the concept is not significantly
`different with three or more sensors 112 used to form a cross
`
`gross minute ventilation, Tidal Volume/Breath Distention (in
`conjunction with the oximetry) and a numberofbreath timing
`parameters.
`[0056] Both the oximetry 154 and respiratory 174 modules
`ofthe sensors 112 are controlled by software 182 loaded onto
`the PC 114, whichis preferably a standard Windows®-based
`PC. Both modules 154 and 174 will connect to the PC 114 via
`
`USBports. All parametric data can be savedto files, and select
`raw parameters can be accessed directly in analog form and
`fed into a recording device of the user’s choosing.
`[0057] The representative example of FIGS. 6 and 7 has
`been built and has the following characteristics. The subject
`or patient interface uses and foot wrap oximeter sensor 152
`and associated module 154 and utilizes a Salter Labs dual-
`
`lumennasal cannula with one lumen delivers supplemental
`oxygen andthe other lumenis used by the system to measure
`airflow.
`
`the computer requirements
`In the sample built
`[0058]
`include a PC with Pentium®-class processor (Pentium 1 GHz
`or higher recommended). The PC included a CD-ROMdrive
`with a VGAor higher resolution monitor (Super VGA rec-
`ommended). The operating system may be Windows® 2000,
`XP or Vista. The proposed memory was 512 MB RAM with
`10 MB Hard-Drive Space for program (which does not
`include data files). The preferred Minimum Screen Resolu-
`tion is 1024 by 768 pixels. The Communications for the PC
`includedat least two USBports(the oximeter module