WO1996032883A1 - Method and apparatus for noninvasively determining hematocrit - Google Patents

Method and apparatus for noninvasively determining hematocrit Download PDF

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Publication number
WO1996032883A1
WO1996032883A1 PCT/US1996/004547 US9604547W WO9632883A1 WO 1996032883 A1 WO1996032883 A1 WO 1996032883A1 US 9604547 W US9604547 W US 9604547W WO 9632883 A1 WO9632883 A1 WO 9632883A1
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WO
WIPO (PCT)
Prior art keywords
signals
current
blood
body portion
voltage
Prior art date
Application number
PCT/US1996/004547
Other languages
English (en)
French (fr)
Inventor
Paul W. Ruben
Allan L. Kaminsky
Original Assignee
Microcor, Inc.
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from US08/425,404 external-priority patent/US5526808A/en
Priority claimed from US08/602,700 external-priority patent/US5642734A/en
Application filed by Microcor, Inc. filed Critical Microcor, Inc.
Priority to AU53837/96A priority Critical patent/AU5383796A/en
Priority to EP96910716A priority patent/EP0955871A4/en
Priority to JP53176596A priority patent/JP3844779B2/ja
Priority to CA002218281A priority patent/CA2218281C/en
Publication of WO1996032883A1 publication Critical patent/WO1996032883A1/en

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Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/48—Biological material, e.g. blood, urine; Haemocytometers
    • G01N33/483—Physical analysis of biological material
    • G01N33/487—Physical analysis of biological material of liquid biological material
    • G01N33/49—Blood
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/145—Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value ; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue
    • A61B5/14535—Measuring characteristics of blood in vivo, e.g. gas concentration or pH-value ; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid or cerebral tissue for measuring haematocrit
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/48—Other medical applications
    • A61B5/4869—Determining body composition
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61B—DIAGNOSIS; SURGERY; IDENTIFICATION
    • A61B5/00—Measuring for diagnostic purposes; Identification of persons
    • A61B5/72—Signal processing specially adapted for physiological signals or for diagnostic purposes
    • A61B5/7235—Details of waveform analysis
    • A61B5/7264—Classification of physiological signals or data, e.g. using neural networks, statistical classifiers, expert systems or fuzzy systems

Definitions

  • Hematocrit is traditionally obtained by acquiring a patient blood sample from a vein via a syringe, or by use of a capillary tube from a finger stick, or puncture.
  • the blood contained in an elongated vessel, is then centrifuged and the height percentage of the column of blood in the vessel which is solid represents the hematocrit.
  • FIG. 3A shows a representation of the total impedance in a limb at a low blood volume
  • Zy is equivalent to Z R in parallel with Z B , where Z B is the blood present at higher volume that is not present at lower volume.
  • impedance Z R is calculated through equation (17), below:
  • blood impedance Z B includes both a magnitude and phase, the phase appears to be the stronger indicator of hematocrit.
  • both phase and magnitude of Z B may be used in pattern analysis in a neural network.
  • a large number of steps may be used to average out arterial pulsation noise, but takes more time and, therefore, there is a greater risk that the blood volume will undesirably and unpredictably change over time with a longer measurement. It has been found by the inventors t at the phase change increases (as a negative number) from about 10 kHz to in the region of 1.6 MHz and then begins to decrease (although there may be an inflection point at well below 1.6 MHz), (de Vries, P.M.J.M., et al., "Implications of the dielectrical behavior of human blood for continuous on-line measurement of hematocrit", Med. Biol. Eng.
  • a "scan” refers to the process of applying signals of various frequencies in steps between a lower and upper frequency limit to electrode 48A. As described above, this creates a current between electrodes 48A and 48B, and a voltage between electrodes 50A and 50B. It takes about one 55th of a second to gather V,, V Q , , and C Q signals at each frequency. Digital filter 128 requires about 9 milliseconds to achieve the desired 60 Hz bandwidth.
  • digital filter 128 processes P ⁇ for 9 milliseconds and then processes Pyj for 9 milliseconds at one frequency. The processes is then repeated for 9 milliseconds for P CT and then 9 milliseconds for Py, at another frequency.
  • the corresponding digital filter in mixer and filter 106 similarly processes P CQ and P VQ .
  • Neural network 52 may be in PC 42 or an adjacent PC or other computer. Accordingly, in FIG. 4, neural network 52 is shown in dashed lines.
  • the neural network could consider parameters including frequency, magnitude, phase, and derivations thereof.
  • the neural network could consider parametes including the patient's age, weight, sex, temperature, illiness, heat applied to the limb, blood pressure, and arm elevation and position. Of course, it is not necessary that the neural network consider each of these parameters.
  • the neural network would also consider the hematocrit measurements from centrifuging capillary tubes corresponding to the patient from which the other factors were obtained.
  • the neural network is able to process out the small vessel effect and produce the hematocrit value due to blood contained in large vessels.
  • Air pump, solenoid(s'). and pressure cuff 28 There are various methods of changing the blood volume. For example, if limb 44 is a finger, blood volume may be change through venous restriction about the upper arm of the patient, or arterial occlusion of the wrist of the patient.
  • microprocessor 94 When it is time to decrease the pressure in cuff 156, microprocessor 94 activates solenoid 168 through which tube 162 is connected to an exhaust. Air pump 152 may be turned on under separate switch or under the control of micro-processor 94. The volume change should be maximized by adjusting the tilt and height of the patient's arm.
  • frequency generator 100 low pass filters 116 and 128, and mixer and filters 104 and 106 are performed in hardware (including programmed dedicated hardware with, for example, adders, multipliers, and gate arrays) as opposed to a microprocessor.
  • some or all of the functions may be performed in PC 42, in another microprocessor system, or otherwise in software.
  • resistance 10 in circuit path 12 representing the response of the extracellular or plasma component
  • the parallel circuit path 14 representative of the erythrocyte or red blood coipuscle component
  • whole blood impedance is attributable primarily to the extracellular blood component circuit path 12, while at higher frequencies (for example, 1 MHz) the capacitive nature of the cell membrane of the red blood corpuscles results in a more significant impedance contribution from circuit path 14, reducing the magnitude of the whole blood impedance.
  • FIG. 15 of the drawings comprises a representative sector of a demodulated voltage signal envelope over a period of time as measured by sensors attached to an electrically-stimulated extremity of a patient according to the present invention, the measured voltage being directly proportional to and therefore representative of the total impedance of the whole blood plus the surrounding tissue.
  • the signal envelope includes a dominant DC or baseline component and a small AC or pulsatile component.
  • the DC component is generated by the patient's tissue, non- pulsatile arterial blood, and venous and capillary blood of the stimulated body portion.
  • the AC component is attributable only to the pulsatile blood, and is therefore truly representative of whole blood impedance for a given frequency.
  • AC components at different frequencies will have substantially identical voltage envelope shapes, differing only in magnitude due to the aforementioned frequency-dependent nature of the whole blood impedance response.
  • the impedance effects of the patient's extravascular tissue are eliminated and a hematocrit determination may be made using the ratio of a low-frequency pulsatile impedance to a high-frequency pulsatile impedance.
  • each frequency excites the tissue of body portion 220 with a constant current, and the resulting voltage signal at each frequency is measured from inner sensor electrodes 224. Since the current excitation is constant, the envelope of the measured voltage at each frequency is directly proportional to the tissue impedance at that frequency.
  • Segments of the converted analog values from Detectors 230 and 232 are then repeatedly extracted over identical time periods by Microcomputer 236, correlated to further reduce noise effects, and then normalized by dividing by the voltage baseline of their respective carrier waveforms before a series of ratios of the time-matched digitized pulsatile component signal segments at frequencies A and B are calculated.
  • the ratios are averaged in a preferred embodiment using weighted averaging techniques well known in the art, relative weighting being based upon the change in voltage magnitude versus time for the time period over which the digitized signals are extracted. Stated another way, the greater the ⁇ V per _U for a pair of time-matched component segments, the more significant the resulting ratio and the more heavily the ratio is weighted in the averaging process.
  • the frequency range of greatest interest previously believed to lie between 50 kHz and 1 MHz, has been proven to be somewhat different and expanded at the high frequency end.
  • the preferred frequency range has subsequently been established to he substantially between 100 kHz and 10 MHz to 20 MHz.
  • C TM Cell Membrane Capacitance of Tissue
  • This modified small signal approach is effected by applying a mechanical "assist" to the limb under measurement. To understand the basis for this "assist,” consider what happens when a blood pressure cuff is applied to a limb and taken through an inflation- deflation cycle.
  • the tiny fraction of blood that is able to completely traverse the occlusion zone is nearly pure plasma, because plasma is less viscous than whole blood and the resistance of the nearly totally occluded artery is very high. As the cuff pressure continues to decrease, the resistance presented to the blood also decreases, and more cellular components are able to flow.
  • the desirable effect being sought is one where the artery remains occluded for at least a small portion of the cardiac cycle and where the blood traversing the occlusion zone is representative of whole blood, at least over time.
  • the cuff pressure is in the region of mean arterial pressure.
  • This pressure zone is non-critical and corresponds to the pressure region where the amplitude of the plethysmographic component of the signal becomes a maximum.
  • the cuff is applied to the body portion (limb) in question proximate the stimulation and sensor electrodes. It is feasible to place the cuff either proximally, distally or over the electrodes, there at present being no identified preferred location for the cuff relative to the electrodes.
  • Pressure in the cuff and inflation and deflation thereof may be controlled via a pump, bleed valve and sensor (pressure transducer) as known in the art, which devices are preferably under control of the microcomputer of the hematocrit determination apparatus.
  • a large shift in blood is effected by the system and method described in connection with FIGS. 3-10.
  • the nature of the method is such that blood flow artifact is eliminated.
  • the same concept of subtracting out the background tissue impedance is employed, using the equations that result from solving the parallel model.
  • the measurement points of interest using a blood pressure cuff and impedance determination electrodes and circuitry are found as follows: the cuff is inflated initially to suppress the plethysmographic signal; as the cuff is deflated, systolic pressure is the point at which the plethysmographic waveform reappears; as cuff deflation continues, mean arterial pressure is the point of maximum intensity of the plethysmographic signal; as cuff deflation continues still further, diastolic pressure is that at which the morphology of the plethysmographic waveform ceases to undergo further change with continued cuff deflation. D.

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  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Biomedical Technology (AREA)
  • Physics & Mathematics (AREA)
  • Molecular Biology (AREA)
  • Biophysics (AREA)
  • Pathology (AREA)
  • General Health & Medical Sciences (AREA)
  • Veterinary Medicine (AREA)
  • Hematology (AREA)
  • Animal Behavior & Ethology (AREA)
  • Medical Informatics (AREA)
  • Public Health (AREA)
  • Heart & Thoracic Surgery (AREA)
  • Surgery (AREA)
  • Chemical & Material Sciences (AREA)
  • Food Science & Technology (AREA)
  • Urology & Nephrology (AREA)
  • Ecology (AREA)
  • Optics & Photonics (AREA)
  • Medicinal Chemistry (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Measurement And Recording Of Electrical Phenomena And Electrical Characteristics Of The Living Body (AREA)
  • Measuring Pulse, Heart Rate, Blood Pressure Or Blood Flow (AREA)
  • Measurement Of The Respiration, Hearing Ability, Form, And Blood Characteristics Of Living Organisms (AREA)
  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
PCT/US1996/004547 1995-04-20 1996-04-03 Method and apparatus for noninvasively determining hematocrit WO1996032883A1 (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
AU53837/96A AU5383796A (en) 1995-04-20 1996-04-03 Method and apparatus for noninvasively determining hematocri t
EP96910716A EP0955871A4 (en) 1995-04-20 1996-04-03 METHOD AND APPARATUS FOR NON-INVASIVE DETERMINATION OF HEMATOCRITIS
JP53176596A JP3844779B2 (ja) 1995-04-20 1996-04-03 非侵襲的にヘマトクリットを測定するための方法およびその装置
CA002218281A CA2218281C (en) 1995-04-20 1996-04-03 Method and apparatus for noninvasively determining hematocrit

Applications Claiming Priority (6)

Application Number Priority Date Filing Date Title
US08/425,404 US5526808A (en) 1990-10-04 1995-04-20 Method and apparatus for noninvasively determining hematocrit
US48449095A 1995-06-07 1995-06-07
US425,404 1996-02-16
US08/602,700 US5642734A (en) 1990-10-04 1996-02-16 Method and apparatus for noninvasively determining hematocrit
US602,700 1996-02-16
US484,490 1996-02-16

Publications (1)

Publication Number Publication Date
WO1996032883A1 true WO1996032883A1 (en) 1996-10-24

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EP (1) EP0955871A4 (ja)
JP (1) JP3844779B2 (ja)
CN (1) CN1244779A (ja)
AU (1) AU5383796A (ja)
CA (1) CA2218281C (ja)
WO (1) WO1996032883A1 (ja)

Cited By (26)

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ES2143911A1 (es) * 1997-03-06 2000-05-16 Nte Sa Metodo y aparato para medir la concentracion y composicion de biomasa.
WO2001088521A1 (en) * 2000-05-16 2001-11-22 Microcor, Inc. System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography
US6615077B1 (en) 2000-08-14 2003-09-02 Renal Research Institute, Llc Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedence
US6766191B1 (en) 1990-10-04 2004-07-20 Microcor, Inc. System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography
EP1622508A2 (en) * 2003-05-12 2006-02-08 Cheetah Medical Inc System, method and apparatus for measuring blood flow and blood volume
US7228170B2 (en) 2000-08-14 2007-06-05 Renal Research Institute, Llc Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedance
US7491174B2 (en) 2003-03-25 2009-02-17 Renal Research Institute, Llc Device and method for performing electrical impedance tomography
US7955492B2 (en) 2004-04-19 2011-06-07 Panasonic Corporation Method for measuring blood components and biosensor and measuring instrument for use therein
US7981281B2 (en) 2008-07-09 2011-07-19 Baxter International, Inc. Dialysis system having regimen generation methodology
US8057679B2 (en) 2008-07-09 2011-11-15 Baxter International Inc. Dialysis system having trending and alert generation
US8062513B2 (en) 2008-07-09 2011-11-22 Baxter International Inc. Dialysis system and machine having therapy prescription recall
US8088271B2 (en) 2003-12-04 2012-01-03 Panasonic Corporation Method of measuring hematocrit (Hct), sensor used in the method, and measuring device
US8168063B2 (en) 2008-07-09 2012-05-01 Baxter International Inc. Dialysis system having filtering method for determining therapy prescriptions
US8388545B2 (en) 2005-02-15 2013-03-05 Cheetah Medical, Inc. System, method and apparatus for measuring blood flow and blood volume
US8523777B2 (en) 2007-04-19 2013-09-03 Cheetah Medical, Inc. Method, apparatus and system for predicting electromechanical dissociation
US8535497B2 (en) 2003-12-04 2013-09-17 Panasonic Corporation Method of measuring blood component, sensor used in the method, and measuring device
US8764667B2 (en) 2007-03-07 2014-07-01 Cheetah Medical, Inc. Method and system for monitoring sleep
US8790267B2 (en) 2007-08-13 2014-07-29 Cheetah Medical, Inc. Dynamically variable filter
US8876725B2 (en) 2007-02-23 2014-11-04 Cheetah Medical, Inc. Method and system for estimating exercise capacity
US8926551B2 (en) 2009-07-07 2015-01-06 Baxter Healthcare Inc. Peritoneal dialysis therapy with large dialysis solution volumes
WO2015178924A1 (en) 2014-05-23 2015-11-26 Nova Biomedical Corporation Hemolysis detection method and system
US9247905B2 (en) 2009-04-17 2016-02-02 Biovotion Ag Wide band field response measurement for glucose determination
US9381290B2 (en) 2009-05-20 2016-07-05 Baxter International Inc. System and method for pairing a dialysis machine with peripheral devices
US9514283B2 (en) 2008-07-09 2016-12-06 Baxter International Inc. Dialysis system having inventory management including online dextrose mixing
WO2019014241A1 (en) * 2017-07-11 2019-01-17 Fresenius Medical Care Holdings, Inc. TECHNIQUES FOR DETERMINING FLUID VOLUMES USING BIO-IMPEDANCE INFORMATION
US10433735B2 (en) 2011-07-25 2019-10-08 Cheetah Medical, Inc. Method and system for monitoring hemodynamics

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WO1999039627A1 (en) * 1998-02-04 1999-08-12 Dermal Therapy (Barbados) Inc. Method and apparatus for non-invasive determination of glucose in body fluids
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US7356366B2 (en) 2004-08-02 2008-04-08 Cardiac Pacemakers, Inc. Device for monitoring fluid status
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JP4640608B2 (ja) * 2005-12-12 2011-03-02 ソニー株式会社 検出装置及び検出方法
JP5071767B2 (ja) * 2006-12-08 2012-11-14 学校法人日本大学 生体組織血流量測定装置
JP5071768B2 (ja) * 2006-12-08 2012-11-14 学校法人日本大学 血流速度測定装置
AU2009294179B2 (en) * 2008-09-22 2015-01-22 Cheetah Medical Inc. System and method for determining blood flow
JP2011078443A (ja) * 2009-10-02 2011-04-21 Tanita Corp 生体測定装置
EP2675349B1 (en) 2011-02-17 2017-10-18 QUALCOMM Incorporated A method of and a system for determining a cardiovascular quantity of a mammal
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JP5726662B2 (ja) * 2011-07-22 2015-06-03 学校法人上智学院 血液インピーダンス計測装置、人工透析装置及び血液のインピーダンスを計測する装置の作動方法
US8623660B2 (en) * 2011-09-30 2014-01-07 Lifescan Scotland Limited Hand-held test meter with phase-shift-based hematocrit measurement circuit
CN103149132B (zh) * 2013-03-18 2015-02-25 深圳市理邦精密仪器股份有限公司 提高测量红细胞压积准确度的检测系统、及运行控制方法
US20150196224A1 (en) * 2014-01-16 2015-07-16 Dermal Therapy (Barbados) Inc. Implantable Sensor and Method for Such Sensor
CN105403691B (zh) * 2016-01-01 2017-08-18 赛奥生物科技（青岛）有限公司 一种血液试剂分析系统
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JP6895876B2 (ja) * 2017-12-13 2021-06-30 アークレイ株式会社 血液中のヘマトクリット値を測定する測定方法および測定装置
WO2020232706A1 (zh) * 2019-05-23 2020-11-26 麦层移动健康管理有限公司 测量体液及其变化以及测量血流量变化的方法和装置

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US6766191B1 (en) 1990-10-04 2004-07-20 Microcor, Inc. System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography
ES2143911A1 (es) * 1997-03-06 2000-05-16 Nte Sa Metodo y aparato para medir la concentracion y composicion de biomasa.
WO2001088521A1 (en) * 2000-05-16 2001-11-22 Microcor, Inc. System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography
US6615077B1 (en) 2000-08-14 2003-09-02 Renal Research Institute, Llc Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedence
US7228170B2 (en) 2000-08-14 2007-06-05 Renal Research Institute, Llc Device and method for monitoring and controlling physiologic parameters of a dialysis patient using segmental bioimpedance
US7491174B2 (en) 2003-03-25 2009-02-17 Renal Research Institute, Llc Device and method for performing electrical impedance tomography
EP1622508A2 (en) * 2003-05-12 2006-02-08 Cheetah Medical Inc System, method and apparatus for measuring blood flow and blood volume
EP1622508A4 (en) * 2003-05-12 2009-05-13 Cheetah Medical Ltd SYSTEM, METHOD AND DEVICE FOR MEASURING THE BLOOD FLOW AND THE BLOOD VOLUME
US8414498B2 (en) 2003-05-12 2013-04-09 Cheetah Medical, Inc. System, method and apparatus for measuring blood flow and blood volume
US8088271B2 (en) 2003-12-04 2012-01-03 Panasonic Corporation Method of measuring hematocrit (Hct), sensor used in the method, and measuring device
US8535497B2 (en) 2003-12-04 2013-09-17 Panasonic Corporation Method of measuring blood component, sensor used in the method, and measuring device
US9719956B2 (en) 2003-12-04 2017-08-01 Panasonic Healthcare Holdings Co., Ltd. Method of measuring blood component, sensor used in the method, and measuring device
US8540864B2 (en) 2003-12-04 2013-09-24 Panasonic Corporation Method of measuring blood component, sensor used in the method, and measuring device
US8480869B2 (en) 2003-12-04 2013-07-09 Panasonic Corporation Method of measuring hematocrit (Hct), sensor used in the method, and measuring device
US9213012B2 (en) 2003-12-04 2015-12-15 Panasonic Healthcare Holdings Co., Ltd. Method of measuring blood component, sensor used in the method, and measuring device
US7955492B2 (en) 2004-04-19 2011-06-07 Panasonic Corporation Method for measuring blood components and biosensor and measuring instrument for use therein
US9285335B2 (en) 2004-04-19 2016-03-15 Panasonic Healthcare Holdings Co., Ltd. Method for measuring blood components and biosensor and measuring instrument for use therein
US8524055B2 (en) 2004-04-19 2013-09-03 Panasonic Corporation Method for measuring blood components and biosensor and measuring instrument for use therein
US8388545B2 (en) 2005-02-15 2013-03-05 Cheetah Medical, Inc. System, method and apparatus for measuring blood flow and blood volume
US10617322B2 (en) 2005-02-15 2020-04-14 Cheetah Medical, Inc. System, method and apparatus for measuring blood flow and blood volume
US8876725B2 (en) 2007-02-23 2014-11-04 Cheetah Medical, Inc. Method and system for estimating exercise capacity
US8764667B2 (en) 2007-03-07 2014-07-01 Cheetah Medical, Inc. Method and system for monitoring sleep
US8523777B2 (en) 2007-04-19 2013-09-03 Cheetah Medical, Inc. Method, apparatus and system for predicting electromechanical dissociation
US10842386B2 (en) 2007-08-13 2020-11-24 Baxter International Inc. Dynamically variable filter
US9095271B2 (en) 2007-08-13 2015-08-04 Cheetah Medical, Inc. Dynamically variable filter
US8790267B2 (en) 2007-08-13 2014-07-29 Cheetah Medical, Inc. Dynamically variable filter
US8257582B2 (en) 2008-07-09 2012-09-04 Baxter International Inc. Dialysis system and machine having therapy prescription recall
US8168063B2 (en) 2008-07-09 2012-05-01 Baxter International Inc. Dialysis system having filtering method for determining therapy prescriptions
US7981281B2 (en) 2008-07-09 2011-07-19 Baxter International, Inc. Dialysis system having regimen generation methodology
US8512554B2 (en) 2008-07-09 2013-08-20 Baxter International Inc. Dialysis system and machine having therapy prescription recall
US9141760B2 (en) 2008-07-09 2015-09-22 Baxter International Inc. System and method for selection of stored dialysis therapy prescriptions
US9149570B2 (en) 2008-07-09 2015-10-06 Baxter International Inc. Dialysis system having filtering method for determining therapy prescriptions
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EP0955871A1 (en) 1999-11-17
CA2218281C (en) 2004-08-17
AU5383796A (en) 1996-11-07
CN1244779A (zh) 2000-02-16
JP3844779B2 (ja) 2006-11-15
CA2218281A1 (en) 1996-10-24
EP0955871A4 (en) 2000-03-22
JP2001500392A (ja) 2001-01-16

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