TW577726B - System and method for in-vivo hematocrit measurement using impedance and pressure plethysmography - Google Patents

Abstract

Assemblages for noninvasively measuring the hematocrit of blood (i.e., the percentage of whole blood volume occupied by red blood cells) through a body part, such as a finger, of an individual. Each of the assemblages includes two pairs of electrodes (20). The electrodes (20) of the assemblage may be carried upon a substrate (32) (Fig. 4). An assemblage of the invention may include a retention component (27) (Fig. 2) for securing the electrodes to the body part. A pressurization component (50) (Fig. 8) may be included to apply pressure externally to the body part.

Description

577726 A7 __B7 _ V. Description of the Invention (Technical Field) The present invention relates generally to a device and method for non-invasive measurement of blood cell volume in a living body, and more specifically to use, Device and method for measuring impedance and pressure plethysmography. [Background technology] The "blood cell volume" of blood is defined as the percentage of red blood cells (erythrocytes) in the total blood volume, blood loss caused by trauma, disease, and iron consumption during pregnancy Insufficient iron intake and some more specific medical symptoms are an important measure of patient health. Hematocrit has been conventionally measured by centrifuging a column of blood drawn from a patient's body in a glass tube until the red blood cells are compressed by the centrifugal force to one end of the tube. The hematocrit is determined by measuring the length of the tube containing the dark red material and dividing it by the total length of the liquid column in the tube. Observations of these lengths are usually made visually, but in some cases, they can also be made with automated optical mechanisms of various designs. In addition to the centrifugal hematocrit measurement, the hematocrit is also exported and reported by a variety of different hematology analyzers, where these hematology analyzers optically calculate red blood cells in unpackaged blood. This red blood cell calculation is related to the packed cell blood cell volume, and the derived blood cell volume is reported. Please note that the methods used to obtain the blood cell volume described above are invasive, that is, they need to remove blood from the patient in order to determine the blood cell. 3 This paper size applies the Chinese National Standard (CNS) A4 (210 X 297) Li) ----- — — — — —----- — — — — — — — II Order — — — — — — (Please read the notes on the back before filling out this page) 577726 A7 ___B7_____ 5. Description of the invention () (Please read the notes on the back before filling this page) Volume. A non-invasive method is satisfactory because it will subject the patient to less pain and inconvenience and will preserve the patient's blood for normal functioning. Biomedical researchers have long acknowledged that the electrical impedance of blood varies with blood cell volume, and because of this relationship, the blood cell volume should be deduced from the measurement of blood impedance. The blood cell volume has been successfully determined by blood impedance measurement. The blood is drawn from the patient and placed in a controlled size impedance measurement cell, which contains a fixed volume of the blood and is maintained at A known temperature and agitation to maintain uniform cell distribution. Several such successful measurement cases have been proposed in "An Electrical Method to Determine Hematocrits" by Okada and Schwan, IRE Transactions in Medical

Electronics, ME-7: 188-192 (1960) and "Implications of the Dielectrical Behavior of Human Blood for Continuous Online Measurement of Hematocrit" by DeVries et al., Medical & Biological Engineering and Computing, pages 445-448 (1993 ) (Hereafter referred to as "deVries"). However, like centrifugation, these methods are invasive and therefore cannot meet the needs of a non-invasive blood cell volume measurement. However, these impedance methods provide inspiration to some smart inventors for non-invasively measuring the volume of blood cells in vivo. The first in vivo impedance measurement of blood cell volume known to these inventors was developed by Yamakoshi et al. In the "Noninvasive Measurement of

Hematocrit by Electrical Admittance Plethysmograph 4 This paper size is applicable to Chinese National Standard (CNS) A4 (210 X 297 mm) 577726 A7 __B7____ 5. Description of the invention ()

"Technology", IEEE Transactions, BMB-27, 3: 156-161 (1980). This measurement method involves immersing the finger of the test subject in the salt contained in a chamber equipped with an impedance measurement electrode Achieved in aqueous solution. Then, the electrolyte concentration of the saline solution is changed by mixing water or more concentrated saline until the change in impedance pulsation caused by the increased volume of blood at each pulse beat is minimized. When When this minimization of the pulse occurs, the resistivity of the saline solution is the same as the resistivity of the blood in the pulsating arteries, and the resistivity is known to be between the resistivity and the blood cell volume, The previously decided relationship is relatively related. US Patent No. 5,526,808 (hereinafter referred to as "the '808 Patent") granted to Kaminsky and assigned to Microcor, Inc. (the assignee of the present invention) describes another Impedance method for measuring blood cell volume in a living body and non-invasively. This method uses the observation of blood cell volume to determine the frequency curve of blood versus impedance. In addition, The method of the '808 patent uses the pulsation changes in impedance that occur on a finger or on other limbs of the body each time a new heartbeat advances the blood to the measured organ to separate it from the blood impedance. Non-blood tissue impedance. The mathematical model on which this method is based relies on the assumption that when blood pulsates into a finger or other body part that is measuring blood volume, the admittance (ie The reason for the inverse impedance) change is because the increased volume of the blood before the pulse wave provided a new current path in parallel with the original current path. Therefore, when there is no new blood in the limb between the baselines At that time, and when new arterial blood has flowed into the limb during the pulse wave, the admittance difference is due to the new blood. The paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ------------ I --------- i IIIIII Order I I ----- (Please read the notes on the back before filling this page) 577726 A7 __B7____ V. Description of the invention () due to liquid. This admittance The number is proportional to the new blood volume multiplied by the admittance of the new blood. As shown in the deVries patent, the admittance of blood has a characteristic shape for the frequency characteristic, which depends on the blood cell volume. Compare this The size or phase shape of the admittance frequency is derived for use in the pulsating blood. The attached shape system provides a measurement of the hematocrit volume relative to the known characteristic blood cell volume. These known characteristic shapes can be obtained from a The database was derived from patients who independently measured the volume of blood cells by the centrifugal method previously described. In granting Ruben et al. And transferring to Microcor, Inc. U.S. Patent No. 5,642,734 (the assignee of the present invention) (hereinafter referred to as "the '734 patent") describes additional methods for obtaining blood cell volume results in a living body. First, the '734 patent describes the use of a pressured cuff to change the amount of blood in an organ (such as a finger) that measures the volume of blood cells in a non-invasive manner through various methods. Second, the '734 patent case describes a unique electronic system for driving the electrodes attached to the body part under measurement and for deriving the phase and amplitude from the impedance measurement of the body part Information. Third, the '734 patent teaches the use of a neural network computer algorithm to correlate measured impedance and other data with the volume of blood cells based on matching a database obtained from a number of individuals. To determine the patient's previous measurement of blood cell volume. In the field of blood oxygen saturation measurement, it is the opposite of the field of blood blood cell volume measurement that has been discussed so far. Clark 6 is awarded to this paper in accordance with the Chinese National Standard (CNS) A4 specification (210 X 297 public love) " — — — — — — — I! —! · !! I order i — — !! · * 5 ^ (Please read the precautions on the back before filling this page) 577726 A7 ___ Β7 ___ 5. Description of the invention () U.S. Patent No. 5,111,817 (hereinafter referred to as the "'817 patent case") was observed to contain oxygen in the blood in the arteries of a body part (for example, _ fingers) in the measurement state. Accurate measurement of the degree of saturation (Sa0 2) is typically hindered by different blood oxygen saturation levels (Se0 2) in the microvessels of the body part. The '817 patent teaches a method for calibrating the measurement of Sa02 for the effects of Se02. In this method, a pressure cuff applies a pressure to the body part under measurement, and the pressure is equal to the average arterial blood pressure in the body part. As a result, the amount obtained from 1 body part The measurement system is controlled by the effect of actual Sa02 in the body part, so that the measured sao2 is very close to the actual sa02. Although pressure cuffs are known in the art to help non-invasive blood cell measurement Volume and oxygen saturation of blood, and non-invasive measurement of blood cell volume using electrode pairs, but this technology does not teach the specific structure of the device used in non-invasive blood cell volume measurement. [Disclosure of the Invention] The invention includes a device configured to be used for non-invasively measuring the volume of a patient's blood cells. A device incorporating the teachings of the invention includes two or more pairs of electrodes. One pressurization Components can also be combined with the device of the present invention. A first embodiment of an electrode incorporating the teachings of the present invention includes four individual electrodes that are paired Internal pair and external pair. These electrode systems can be substantially L-shaped. One of the first elements of each electrode is configured to be used for contacting and at least partially wrapped around a paper. 7 This paper size applies to China Standard (CNS) A4 specification (210 X 297 mm) V t -------- ^ --------- line (Please read the precautions on the back before filling this page) 577726 A7 ___B7_ V. Description of the invention () A body part whose blood cell volume is non-invasively measured. A second element of each electrode is configured to be used for communication with an external electrical component, and the external electrical component will apply a voltage To the body part or to measure impedance at the body part, the content of this part will be described in more detail below. In a variation of the first embodiment, one or more of these electrode systems may be Substantially linear, one of the first end systems is configured to be used at least partially around a body part and one of the second end systems is configured to be used to be connected to an external electronic component. Electrodes useful for the device of the present invention The two embodiments have two members, each of which includes a flexible substrate and two electrodes, the two electrodes being an electrode of an external pair and an electrode of an internal pair. Preferably, the The flexible substrate conforms to the shape of the body part for which the volume of blood cells is to be measured non-invasively, and may include a substantially flat element or be configured to be used to at least partially house the body part (for example, a It is configured as an open-end or closed-end tube that can at least partially accommodate a finger.) Again, the electrode systems may be substantially L-shaped and include a first element and a second element. Each At least a part of the first element of each electrode is fixed to and carried by the flexible substrate. Therefore, when the first element of each of the L-shaped electrodes is taped with a non-invasive measure The first element of each electrode is also at least partially when the body parts of the blood cell volume are in contact and the flexible base of each of the two members is at least partially wound around the body part Entangled around the body part. In a variation of this second embodiment, one or more of these electrode systems may be substantially linear, one of which has a first end portion of 8 paper sizes that are compliant with Chinese National Standard (CNS) A4 specifications (210 X 297 mm) ----------------------------- Order --------- line (please read the back first Please fill in this page again) 577726 A7 ____B7_____ V. Description of the invention () is configured to be used at least partially wrapped around a body part and one of the second ends is configured to be connected to the outside Electronic components. A third embodiment of the electrode includes a single, flexible substrate that at least partially carries four electrodes. The four electrode systems are arranged in an inner group pair and an outer group pair with respect to the substrate. . Preferably, the flexible substrate conforms to the shape of the body part where the volume of blood cells is to be measured non-invasively, and may include a substantially flat element or be configured for at least partial accommodation The body part (eg, an open-ended or closed-ended tube configured to at least partially hold a finger). The electrodes may be L-shaped, as described previously herein with respect to the first and second electrode embodiments, or may be substantially linear, and they may be configured to communicate with external electronic components. The device incorporating the teachings of the present invention also includes a pressurizing member configured to be used to apply a predetermined amount of pressure to a body part that is intended to measure the volume of blood cells in a non-invasive manner. One of the first embodiments of the pressurizing member includes a flexible pouch over the internal and external electrode pairs, the flexible pouch being configured to be used at least partially around the body part, So that when the pressure in the pouch increases (for example with air or another fluid), an increased pressure can be applied to the body part. In a second embodiment, a flexible substrate carrying the electrode portions above (as described earlier in the second and third electrode embodiments herein) comprises a flexible pouch. Accordingly, at least a part of at least one of each of these internal and external electrodes can be fixed to the 9 paper standards applicable to China National Standard (CNS) A4 (210 X 297 mm) ------ ------- IIIIII 1 Order. — — — — — — — (Please read the precautions on the back before filling out this page) 577726 A7 ___B7 —_____ V. Description of the invention () Flexible bag or carried by the flexible bag in other ways. Prior to the introduction of pressure into the flexible capsular bag, the capsular bag may be substantially flat or configured to be used to at least partially house the body part (for example, An open-end or closed-end tube that is quilted to at least partially accommodate a finger) ° The flexible bladder embodiments of the pressurized component are configured to be connected to a pressure source . When the flexible bladder is pressurized (e.g., 'by air pressure or by the pressure of another fluid)' pressure is applied to at least a portion of the body part. In addition, the flexible pouch systems may be lined with a socket formed in a rigid element and configured to be used to at least partially receive the body part. In a third embodiment of the pressurized component incorporating the teachings of the present invention, the internal and external electrode pairs (such as those described previously in the first, second, and third electrode embodiments herein) The system is arranged in contact with a body part to be measured for blood volume and is at least partially wrapped around the body part for measurement of blood volume. The body part is inserted at least partially into a pressure chamber, which is in fluid communication with a positive pressure source. One or two electrode portions of the internal and external electrode pairs that are in contact with the body part may also be inserted into the pressure chamber. When the body part is properly positioned within the pressure chamber, an at least partial seal is formed around the body part. Accordingly, when a positive pressure is formed in the pressure chamber, the pressure will be applied to the body part. 10 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) Ψ --- I ------------- I ---- · I — I — III Order --------- (Please read the notes on the back before filling out this page) 577726 A7 -_______ B7___ 5. Description of the invention () A non-invasive measurement of a living body according to the teachings of the present invention The system of ilL (such as a finger) filled blood cell volume includes a non-invasive blood cell volume measurement device and external electronic components combined with it. The electronic components of the system include a circuit system that drives first and second alternating currents of different frequencies (for example, 1 〇 Κ Η z and 1 〇ΜΗ Z) between two separate points on the body part. . The alternating currents can be applied to the body part through input electrodes attached to different points of the body part. Similarly, the additional circuit system monitors the first and second signals (such as voltage) induced in the body part by the first and second currents (for example, by monitoring the output voltage attached to the body part). Waveforms), and other circuit systems generate first and second pulsating signals and first and second baseline signals from the first and second sensing signals. The circuit system is determined, and then the blood cell volume of the blood is calculated from the first and second pulsation signals and the first and second baseline signals. This calculation can be performed, for example, by determining the blood cell volume (Η) from the following equation: [(l + (fl) H) / (lH)] {l + [((af (e-bx-c)) x / (lx))-l] H} / {l + [((af (e-bx-c)) / (lx))-l] H) = C · (△ VoltH / VH2) / (AVoltL / VoltL2 ) Where (: ^ &, 13, \, (:, and 0 are various constants, which will be described below, Δν〇1ίΗ and △ Volk are the first and second pulse signals, and VH and VL Are the first and second baseline signals. According to another embodiment of the system of the present invention, a system for measuring the volume of blood cells filled in a living part includes a body positioned on a surface of the body part. Electrodes. One measuring device is in one or more 11 paper sizes. Applicable to China National Standard (CNS) A4 specification (210 X 297 mm) ----------- I ----- I --- install -------- order --------- line (please read the precautions on the back before filling this page) 577726 A7 _____B7_ V. Description of the invention () Measurements at frequency The electrical impedance between the two electrodes. Similarly, a chamber is positioned to surround the body part between the electrodes to A measuring device measures the pulsating blood volume by the related pulsating change of the internal pressure in the chamber. Further, a computing device (such as a program microprocessor) measures the impedance and the pulsating blood volume. The blood cell volume of the blood is determined. The device can determine the blood cell volume (Η) according to the following equation: f H = (p — 58) / (.  01ρ + · 435), and p = avz〇Vl2az ^ where Δν is the pulsating blood volume change at any point in time, ΔZ is the instant impedance change at the same point, and L is a constant, which will It is described below, and Z 0 is the baseline impedance at the beginning of each pulse. In a further embodiment, the system for determining the blood cell volume includes: a circuit system for generating a current signal, the current signal system including a first relatively low frequency portion and a second relatively high frequency portion; And the blood cell volume measuring device, which stimulates a living body part containing blood with the current signal. Similarly, an additional circuit system of the blood cell volume measuring device is used to sense the voltage induced by the stimulus on the body part at the first and second frequencies, and another circuit system detects the sense A voltage measurement signal packet, wherein each signal packet has a pulsating component and a baseline component. The insulation circuit system isolates the pulsating component and the baseline component of the detected signal packet, and the extraction circuit system extracts one or more sets of the isolated pulsating component. The paper size is in accordance with Chinese National Standards (CNS) A4 size (210 X 297 mm) ------------- install -------- order --------- line (please read the precautions on the back first) (Fill in this page again) 577726 A7 _B7____ 5. Description of the invention () Time matching part and time matching part of one or more groups of the isolated baseline component. Further, other circuit systems effectively correlate the product of the ratio of the blood cell volume to the time-matched portion of the pulsating components and the inverse ratio of the square of the time-matched portion of the baseline components. Another embodiment of the system includes a device for relatively low frequency pulsations and baseline signals induced from the body part and similarly high frequency pulsations and baseline signals induced from the body part To determine the volume of blood and blood cells covered by a living part, the device includes a circuit system that effectively determines the product of the square of the relatively high frequency pulsation signal and the relatively low frequency baseline signal, the relative low frequency pulsation signal, and the relatively high Ratio of the product of the square of the frequency baseline signal. The device also includes circuitry that correlates the blood cell volume with the effectively determined ratio. Other embodiments of the present invention include a method for measuring the volume of blood cells filled in a living part, and a method for determining the volume of blood cells. These methods are generally similar to the systems and devices described above. meets the. Other features and advantages of the present invention will become apparent to those skilled in the art through the following description, accompanying drawings, and consideration of the scope of the accompanying patent application. [Brief description of the drawings] FIG. 1 is a plan view of a substantially linear electrode which is used in the device according to the present invention; FIG. 1A is a 13 of a substantially linear electrode shown in FIG. ; Paper size applies Chinese National Standard (CNS) A4 specification (21G X 297 public love) " 一 " " I I ---- — — — — — — I · --- IIIII Order ------ --- (Please read the notes on the back before filling this page) 577726 A7 _______B7 _ V. Description of the invention () Changes; Figure 2 is a top view of a change of the electrode shown in Figure 1, where the electrode is Shaped into an L-shape; Figure 3 is a perspective view depicting four electrodes shown in Figure 2 partially wrapped around a patient's finger; Figure 4 is a device incorporating the teachings of the present invention A plan view of an embodiment of a component, which includes two electrodes not shown in FIG. 2, which are carried by a substantially planar substrate; FIG. 5 is a drawing depicting two A perspective view of a member shown in which the two members are fixed to a patient Fig. 6 is a plan view of another embodiment of the device according to the present invention, which includes four electrodes shown in Fig. 1, which are fixed to a substantially flat, flexible Base; FIG. 7 is a perspective view illustrating the device of FIG. 6, where the device of FIG. 6 is fixed to a finger of a patient and is electrically connected to external electronic components through an exemplary connector Figure 8 is a perspective view illustrating the four electrodes shown in Figure 2, wherein the electrodes are fixed to one finger of a patient with a pouch embodiment of an independent pressurizing member, The independent pressurizing member is fixed to the finger around the electrodes; FIG. 9 is a plan view of an embodiment of a device according to the present invention, which includes four electrodes shown in FIG. The isoelectrode system is carried on one of the surfaces of a substantially flat flexible pouch; Fig. 10 is a device of the device shown in Fig. 9 and a device for the 14 paper size applicable to Chinese National Standard (CNS) A4 Specifications (210 X 297 mm ) ------------- Installation ---- I --- Order · -------- Line (Please read the precautions on the back before filling this page) 577726 A7 _ B7__ 5. Description of the invention () A perspective view of the electrical connector of the device; Figure 1 1 is a perspective view illustrating a component of another embodiment of the device which is wrapped around a finger of a patient 'the device The system includes a substantially planar pouch element and two electrodes shown in FIG. 1, the two electrodes are fixed to the surface of the pouch element 'and the component system in FIG. 4 is wrapped around one of the fingers Adjacent parts; Figure 12 is a perspective view of yet another embodiment of the device 'The device includes the electrodes shown in Figure 1, the electrodes are carried on an internal surface of a tubular pouch, the tube The pouch is configured for at least partially accommodating a finger; FIG. 13 is a perspective view of a rigid element that includes a socket that is at least partially lined with the one shown in FIG. 9. The device shown; Figure 14 is a perspective view of another embodiment of a pressurizing member of the present invention, The system includes a closed-end pressure chamber configured to accommodate a single finger of a patient; FIG. 15 is a pressurized component incorporating one of the teachings of the present invention Is a perspective view of another embodiment of the invention, which includes a pressure chamber with two open ends, a part of a finger of a patient extends through the two open ends, and the figure shows A finger is in contact with the four electrode parts shown in FIG. 2 inside the pressure chamber; FIG. 16 is a perspective view illustrating the pressure chamber in FIG. 15 and the pressure chamber in FIG. 15 It is configured to surround one finger of a patient and surround two electrodes of the type shown in Fig. 1 that are in contact with the finger. The 15 ^^ dimensions are applicable to the Chinese National Standard (CNS) A4 specification (210 X 297). ) " " ~ " --- I ---- — — — — — ---— — — — — Order ------ 1! * ^ (Please read the notes on the back before filling (This page) 577726 A7 _B7_ 5. The description of the invention (), and the component in Figure 4 is wrapped around one of the fingers next to it Part (Please read the precautions on the back before filling this page) Figure 17 is a block diagram of a blood cell volume measurement system according to the present invention; Figure 18 is a block diagram of another blood cell volume measurement system according to the present invention ; And FIG. 19 is a diagram of a correction system of the blood cell volume measurement system in FIG. 18. [Description of component symbols] 1 finger 2 fingertip 3 finger base 5 alternator 6 amplifier 7 computing system 8 pressure chamber 9 pressure transducer 1 0, 10, electrode 10 1 internal electrode 1 0 external electrode 111 internal Group 1 1 10 External Group 1 2 1 2 1 16 First Paper Size Applicable Chinese National Standard (CNS) A4 (210 X 297 mm) 577726 A7 B7 V. Description of the invention () 1 4 、 1 4, 15 1 7, 1 7 '18 2 0 2 0 0 2 0 1 2 11 2 1〇2 2 2 4 2 7, 2 7' 2 8 2 9 2 9a 2 9b 3 0 3 2 4 0 4 2 4 4 5 0, 5 0 '5 1, 5 1' 5 2 Second end joint end 1 Retaining part electrical connector electrode outer group to inner group to inner group to outer group to first end second end Component Socket end part holding area Necked area device Flexible base electrode device Flexible base connector 5 0 ”Pouch 5 1” Interface catheter (Please read the precautions on the back before filling this page) This paper size applies to Chinese national standards (CNS) A4 specification (210 X 297 mm) 577726 A7 B7 V. Description of the invention (5 4 5 5 5 6 5 7 5 8 6 0, 6 0 ', 6 0 6 11' 6 1〇 '7 0, 7 0' 7 2 8 0 8 2 8 4 9 0, 9 0 ', 9 0 9 1, 9 1 ', 9 1 9 2 92', 9 3 '9 4, 9 4', 9 4 9 5, 9 5 ', 9 5 9 6, 9 6' 9 7, 9 7 '9 8 10 0 10 2 Pressure source solenoid valve socket correction device External surface device Internal group to external group to electrical connector connector device Rigid element socket Pressure chamber rigid element First end open end socket Flexible element pressure port plus Compressor bag compression catheter waveform generator host computer (please read the precautions on the back before filling this page) 18 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 577726 A7 B7 V. Invention Description (converter finger current source sense amplifier complementary pair rectifier pulse wave separator resistor photoresistor resistor light emitting diode (please read the precautions on the back before filling this page) 10 4 10 6 10 8 110 112 114 116 12 0 12 1 12 2 12 3 [Detailed description of the preferred embodiment] It can be fixed on a body part to implement a fen stop FIG measuring apparatus of the blood cell volume of the system 1 may be used to illustrate a first implementation of a method of the present invention of an electrode 1〇 embodiment. The electrode 10 is made of a conductive material, such as a thin metal plate or a metal cleat, and includes a first end portion 12 and an opposite second end portion 14. The first end 12 is configured to be accessible and preferably can be used to at least partially wrap around a body part, such as a finger, wherein the blood cell volume is measured at the body part according to the teachings of the present invention . The second end 14 is configured to be connected to an external electronic component (not shown) for performing a blood cell volume measurement. The first end 12 may include a retaining member 17 on it, as shown in the Chinese National Standard (CNS) A4 specification (210 X 297 male f) 577726 A7 __B7______ as shown in the figure. 5. Description of the invention () Agent to keep the electrode 10 in contact with or surround a body part. Preferably, the pressure-sensitive adhesive of the holding member 17 is a conductive adhesive, which can directly fix the electrode 10 to the body part. Exemplary conductive adhesives include the trade name HYDROGEL® sold by several suppliers such as Avery Dennison 'Specialty Tape Division, of Painesville, Ohio, and by Hydromer, Inc.  AQUATRIXTMn sold by Somerville, New Jersey. Although the viscous holding member 17 is illustrated as covering the entire electrode 10 physically, a viscous holding member 17 may alternatively cover a very small area of the electrode 10, which will adequately secure The electrode 10 is in contact with the body part. For example, the adhesive system of the holding member 17 may be disposed between the electrode 10 and the body part, or the holding member system may be configured and arranged to be adhered to another part of the electrode 10 and make the electrode at least partly Ground is fixed around the body part. Figure 1A shows a variation of one of the substantially linear electrodes 10 '. The electrode 10 'includes a holding member 17', which in this example is a sleeve, which is disposed between a first end portion 12 'and a second end portion 14' of the electrode 10 '. As shown in the figure, the holding member 17 is configured to receive and hold the first end portion of the electrode 10 'when the first end portion 12 is wrapped around a body part whose blood cell volume is to be measured. 12. By pulling the first end portion 12 tightly through the holding member 17 ', the electrode 10' can be tightly fixed to the body part. 20 This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) ------------- Install -------- Order --------- Line (Please read the precautions on the back before filling this page 5) 7726 A7 B7 5. Description of the invention () Figure 2 shows another embodiment of the electrode 20 that can be used in the present invention. The electrode 20 is substantially L-shaped and includes a first element 22 and a second element 24. The electrode 20 is made of a conductive material, for example, a thin metal plate or a metal sandwich plate. The first element 22 of the electrode 20 is configured for contact and preferably for at least partially wrapping around a body part, such as a finger, where the body part is intended according to the method of the present invention. Measure blood cell volume. Fig. 2 illustrates an electrode 20 including an exemplary holding member 27. As shown in the figure, the junction between the first element 22 and the second element 24 includes a socket 28. The socket 2 8 is configured to receive an end portion 29 of the first element 22 when the first element 2 2 surrounds a body part to be measured for blood volume. As shown in Fig. 2, the end portion 2 9 is configured to have a series of holding regions 2 9 a, and adjacent regions have a narrow neck region 2 9 b. The width of the holding area 29a is wider than that of the socket 28, and the width of the necking area 2b is approximately equal to or smaller than the width of the socket 28. Therefore, when the end portion 2 9 is inserted into the socket 2 8, a holding portion 2 9 a is pulled through the holding area 2 9 of the socket 2 8 to fix the end portion 2 9 in the socket 2 8 so that the socket 2 8 and the end portion 2 9 are interconnected. In this manner, the socket 28 and the end portion 29 are interlocked with each other so that the first element 22 is fixed in place around a body part. The second element 24 of the electrode 20 is configured to be usable for connection to an external electronic device for carrying out the method of the present invention. Alternatively, the electrodes 10 or 20 may be made of a deformable material and 21 paper sizes are applicable to China National Standard (CNS) A4 (210 X 297 mm) ------------- ---- Order --------- (Please read the precautions on the back before filling this page) 577726 A7 __B7___ 5. Description of the invention () Made, once the deformable material is deformed, it will be substantial The ground is shaped so that a part of the electrodes 10, 20 can be kept in contact with the body part of the blood cell volume to be measured and the part of the electrodes 10, 20 is fixed to the body part of the blood cell volume to be measured . FIG. 3 illustrates an example of using the electrode 20, wherein the first element 22 of the four electrodes 20 is shown in contact with and wrapped around a body part to be measured for blood cell volume according to the teachings of the present invention. In this example, it is a finger 1. As shown in the figure, the electrodes 2 0 are respectively arranged into an outer group pair 2 1 0 and an inner group pair 2 1 I, wherein the electrodes 2 0 of the inner group pair 2 1 I are separated from each other and the outer group pair The electrode 2 0 of 2 10 is positioned adjacent to the outer side of the electrode 20 of the inner group pair 2 1 I. The interval between the electrodes 20 adjacent to the inner group pair 2 1 I and the outer group pair 2 1 0 is closer than the interval between the electrodes 20 of the inner group pair 2 1 I. FIG. 4 shows a device 30 comprising two electrodes 20, which are partly carried on a flexible substrate 32. As shown in the figure, the flexible substrate 32 is a first element 22 that supports the electrode 20. Exemplary materials that can be used to make the flexible substrate 32 include, without limitation, fabrics, polymers, and other flexible materials. As shown in FIG. 4, the flexible substrate 32 also includes a holding member 27 between the first elements 22, which in this example is some adhesive material. Preferably, the adhesive material 27 is a pressure-sensitive adhesive, which will keep the first element 2 2 in contact with the body part whose blood cell volume is to be measured, and is relative to the body part. The position of the first element 22 is maintained. 22 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) --II --------------- Order -------- (please first Read the notes on the back and fill in this page again) 577726 A7 ____B7_______ 5. Description of the invention () Figure 5 illustrates an example of the use of a device 30 for implementing the method of the present invention. As shown, two devices 30 are positioned on a body part, in this case a finger, where the first element 22 of the electrode 20 is in contact with the body part. As shown in the figure, the distance between the devices 30 is larger than the distance between the electrodes 20 of each device 30. Fig. 6 shows another embodiment of an electrode device 40 which facilitates carrying out the method of the present invention. The device 40 includes a flexible substrate 4 2 which is similar to that shown in FIG. 4 and described with reference to FIG. 4 ′, and the flexible substrate is provided with four electrodes 10. As shown, the electrodes 10 are positioned on the flexible substrate 42 in a substantially parallel relationship with each other. However, devices having electrodes 10 positioned non-parallel to each other are also encompassed within the scope of the invention. The electrodes 10 are arranged into an inner group pair 1 1 I and an outer group pair 1 10. The electrode 10 of the inner group pair 1 1 I is positioned adjacent to each other, while the electrode 10 of the outer group pair 1 10 is positioned outside the electrode 10 of the inner group pair 1 1 I, where the inner group pair 11I The distance between the electrodes 10 is larger than the distance between each electrode 10 of the inner group pair 11I and the electrode 10 of the adjacent outer group pair 110. Preferably, the second end portion 14 of the electrode 10 is configured to be connected to a conventional type of electrical connector, such as shown in FIG. 7. Connector 4 4 person. Figure 7 illustrates a method for using the device 40 to determine the hematocrit of a patient. The device 40 is positioned relative to a body part of a patient (for example, a finger). The first end of the electrode 10 is 1 2 23. This paper size is in accordance with the Chinese National Standard (CNS) A4 specification (210 X 297 mm) --------------------- Order -------- (Please read the precautions on the back before filling this page) 577726 A7 B7 V. Description of the invention () (refer to Figure 6) is in contact with the body part. As shown, the first end 12 of the electrode 10 is at least partially wrapped around the finger 1. The second end portion 14 of the electrode 10 extends beyond an outer periphery of the flexible substrate 4 2 and is connected to a corresponding connector of an electrical connector 4 4. External electronic components (not shown) of the inventive method are in communication. A device according to the present invention may also include a pressurizing device, such as an inflatable bladder 50 shown in FIG. The inflatable pouch 50 can be of any type known in the art, such as a blood pressure cuff for an infant, which can be fixedly wrapped around a body part, such as a finger, on which the body part is borrowed. The blood cell volume is measured by a conventional mechanism such as a complementary hook and loop fastener. As shown, the pouch 50 is separated from the electrode 20, and the electrode 20 is wrapped around a finger 1 in substantially the same manner as described and illustrated with reference to FIG. The bladder 50 is at least partially wrapped around a body part to be measured for blood cell volume, such as finger 1, so that pressure can be applied to the finger to facilitate measurement of the blood cell volume. The bladder 50 and other embodiments of any pressure member used in the present invention can be positioned relative to the body part so that pressure can be applied between the innermost pair of electrodes 6 1 I '. Preferably, the bladder 50 or another pressurizing member is abutted against each electrode of the innermost group pair 61I 'or at least partially overlaps each electrode of the innermost group pair 6I' so that the pressure Apply to the entire part of one of the body parts placed between the innermost group pair 6II '. The bag 5 0 is an external pressure source known in the art. 5 24 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ----------- --- install -------- order --------- line (please read the phonetic notes on the back before filling this page) 577726 A7 _______B7 _ 5. Description of the invention () 4 Connected, For example by using a catheter 52, such as a tube. For example, in one example of the manner in which the internal pressure of the capsular bag 50 can be increased, air or other flow systems can be supplied to the capsular bag 50 from an external pressure source 54 through the conduit 52. When the internal pressure of the pouch 50 is increased, the pressure is supplied to the body part to which the blood cell volume is to be measured. Although FIG. 8 shows that the pouch 50 is wrapped around the finger 1 and all four electrodes 20 on the finger 1, the pouch 50 can be positioned elsewhere on the finger 1 or another body part. For example, between the electrodes 2 0 of the internal group pair 2 1 I or above two adjacent electrodes 20. Figure 9 illustrates another embodiment of a device 60 that can be used to measure the volume of blood cells in accordance with the teachings of the present invention. The device 60 comprises a flexible base 40 which comprises a pouch 50 'which can be pressurized. The bladder 50 'includes an interface 51 to facilitate connection to an external pressure source, such as the external pressure source 54 shown in FIG. For example, a catheter or an end of a tube may be inserted into the interface 51 and may be retained in the interface by an externally protruding rib extending along the circumference, the rib surrounding the Formed by the end of the catheter. The device 60 also includes four electrodes 10, which are carried on one surface of the pouch 50 '. As shown in the figure, the device 60 includes four electrodes 10, and the electrodes 10 are arranged in a parallel relationship with each other. The electrodes 10 are arranged in two groups, including an internal group 1 1 I and an external group 1 1 0. The electrodes 10 of the inner group pair 1 1 I are separated from each other, and the electrodes 10 of the outer group pair 110 are positioned outside the electrodes 10 of the inner group pair 11 and adjacent to the electrodes 1 0 of the inner group pair 1 1 I. , And its 25 paper sizes are applicable to China National Standard (CNS) A4 (210 X 297 mm) --------------------- Order ----- ---- Line (Please read the precautions on the back before filling this page) 577726 A7 ___B7__ 5. Description of the invention () The distance between the two is smaller than the distance between the internal group pair 11I electrode 10 and each other. Preferably, the second end portion 14 of each electrode 10 includes a joint end 15 which extends across the pouch 50 ′.  An outer periphery to facilitate the electrical connection of electrodes 10 and device 60 to external electronic components (not shown) that can implement the method of the present invention. For example, the joint end 15 may be at least partially wrapped around a peripheral edge of the pouch 50 '. Fig. 10 illustrates a situation in which the device 60 is connected to an electrical connector 70 of a conventional type in the art. The electrical connector 70 includes a number of connectors 72, which correspond to the connector ends 15 of the electrode 10 to connect the electrode 10 to a suitable external electronic component (not shown). 0 Figure 1 The 1 series illustrates a device 60 ', which is a modification of the device 60, which includes two electrodes 10 and an electrical connector 70', which is configured to be used for The device 60 'is connected to an external electronic component (not shown) which helps to determine the volume of blood cells of a patient in accordance with the teachings of the present invention. When using the device 60 ', two additional electrodes, such as the electrode 20 of the device 30, must also be in contact with a body part, such as the finger 1, for which the blood cell volume is to be measured. The outermost electrode 20 of the device 30 and the outermost electrode 10 of the device 60 'include an external group pair 6 1 0', while the innermost electrode 20 of the device 30 and the adjacent electrode 10 of the device 60 'include an internal electrode group 61I 'facilitates the measurement of blood cell volume in accordance with the teachings of the present invention. The flexible base of device 60 'is an expandable pouch 50' 26. The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ------- II ---- ---- I --- Order ------- • Line (Please read the precautions on the back before filling this page) 577726 A7 _ B7____ 5. Description of the invention (), which includes an interface 5 1, The bag 5 0 ′ can be pressurized and decompressed through the interface 5 1 ′. Fig. 12 illustrates yet another embodiment of a device 60 "for measuring the volume of blood cells according to the method of the present invention. The device 60" includes an expandable pouch 50 "having a tubular shape. Pouch 50" The system comprises a socket 56, which is configured for at least partly receiving a body part, such as a finger, for which the blood cell volume is to be measured. The first end 12 of the electrode 10 is at least partially carried on an internal surface of the pouch 50 "and exposed to the socket 56. Therefore, once a body part is at least partially inserted into the socket 56 After that, the first end portion 12 of the electrode 10 is in contact with the body part. The second end portion 14 of the electrode 10 is exposed and can extend beyond an external surface 5 8 of the pouch 50 to help It is used to connect the device 60 "to an external electronic component which implements the method of the present invention. The bag 50" also includes an interface 51 ", which assists the pressure and pressure reduction of the bag 50". Figure 13 illustrates a further device 80, which is configured in accordance with the teachings of the present invention to be used to position the electrode 10 in contact with a body part to be measured for blood cell volume and to apply pressure to the body part. . The device 80 series includes a rigid element 82, which can be made of, for example, a polymer. The rigid element 82 series includes a socket 84, which is configured for at least partially receiving one. The part of the body whose blood volume is to be measured. A device is configured inside the socket 84, for example, as shown and described in FIG. The device 6 〇 is arranged inside the socket 8 4, so that once a body part, such as a finger, reaches 27, this paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 public ^ ----- --------------- I ---- Order --------- Line (Please read the precautions on the back before filling this page) 577726 A7 ____B7__ V. Invention Explanation () After a small part is inserted into the socket 84, the first ends 12 of all four electrodes 10 of the device 60 are in contact with the body part. Preferably, the pouch 50 'of the device 60 also Pressure contact with the body in a manner that will take into account the pressure of the body part when the pouch 50 'is pressurized via the interface 51 ". The connector end 15 of the electrode 10 is a conventional type of electrical The connectors 18 are in communication, and the electrical connectors 18 are held inside the rigid element 8 2 and help to connect the electrodes 10 to external electronic components (not shown) to implement a blood cell volume according to the present invention. Measurements Figure 14 illustrates a pressurized chamber 90, which can be used to perform a blood cell volume measurement in accordance with the present invention. As shown, the pressurizing chamber 90 includes a substantially cylindrical, hollow rigid element 9 1, a flexible flexible element 95 in the rigid element 9 1, and a flexible element 9 The socket 9 4 in 9 5. The socket 9 4 is configured to at least partially accommodate a body part to be measured for blood volume, such as a finger 1. The body part can pass through the compression chamber. A first end portion 92 of 90 is inserted into the socket 94. The compression chamber 90 also includes a pressure port 9 6 and a pressure bag composed of a flexible element 95 and a rigid element 9 1. The 9 7 series can be pressurized or depressurized through the pressure port 96. When air or gas is introduced into the pressure bladder 9 7, the flexible element 9 5 series expands into the socket 9 4, and The volume in the socket 9 4 is reduced. Therefore, when air or gas is introduced into the pressure bag 9 7, the flexible element 9 5 is forced to abut a finger 1 arranged in the socket 9 4 Or other body parts, and apply pressure to it. As shown in Figures 14 and 28, this paper size applies Chinese National Standard (CNS) A4 specifications (2 10 X 297 mm) ---! 111! 1_ i! III Order --- — — — — — — — * 5 ^ (Please read the notes on the back before filling this page) 577726 A7 __B7_____ V. Description of the invention ( As shown in the figure, the pressure port 9 6 is configured to be connected to a pressure conduit 9 8, such as a tube, which is in communication with an external pressure source 5 4. Although FIG. A socket 1 4 is provided with a finger 1 and four electrodes 20, wherein each of the first ends 22 of the electrodes 20 is at least partially wrapped around the finger. However, a socket 1 4 may be provided with Four or fewer electrodes 20 in contact with a part of the finger 1 or another body part. Fig. 15 illustrates another pressurizing chamber 90 'that can be used in the method of the present invention. The pressurizing chamber 90 'is composed of a substantially cylindrical, hollow rigid element 9 1', and an elastic flexible element 9 5 'inside the rigid element 9 1'. The flexible element 9 5 'forms a socket 9 4' in the pressurizing chamber 90 '. A pressure bladder 9 7 'is formed between the rigid element 9 1' and the flexible element 9 5 '. The pressure chamber 9 0 'also includes two opposite open ends 9 2' and 9 3 '. Both ends 9 2 'and 9 3' are continuous with one socket 9 4 'of the pressurizing chamber 9 0'. The pressure chamber 9 0 'is in communication with an external pressure source 54 through a conduit 98, which is connected to a pressure port 96' of the pressure chamber 9 0 '. The pressurized bladder 9 7 'can be pressurized by introducing air, gas, or another pressurizing medium into the pressurizing port 96' through the pressurizing port 96 '. When a positive pressure is formed in the compression bag 97 ', the flexible member 95' is forced toward the socket 94 ', so that the volume of the socket 94' is reduced. Therefore, when the positive pressure is introduced into the compression bag 9 7 ', the flexible element 9 5' is pushed to a finger 1 or other body part arranged in the socket 9 4 'and the Its pressure is 29. The paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm) ----- I--I ---- installation -------- order ---- ----- Line (Please read the precautions on the back before filling this page) 577726 A7 ___B7 __ V. Description of the invention (). As shown in FIG. 15, the pressurizing chamber 90 ′ is configured to partially receive the finger 1, wherein a base 3 of one of the fingers 1 extends through the end 9 2 ′ and a fingertip of the finger 1. The 2 series extends through y and the portion 9 3. Fig. 15 also shows that all the first end portions 22 of the four electrodes 20 wound around the finger 1 are disposed in the cavity 9 4 ′. Although FIG. 15 shows that the four electrodes 20 in contact with the finger 1 are all at least partially disposed in the cavity 9 4 ′, as shown in FIG. 16, the finger 1 or the blood cell volume to be measured Additional body parts can be placed in one of the sockets 9 0 ″ of a pressurized chamber 90 ″, so that the electrode system provided in the chamber 9 4 ″ is less than four electrodes 10. As shown in the figure It is shown that the electrode 10 is a rigid element 9 1 ″ and a flexible element 9 5 ″ extending through the pressurizing chamber 90 ″. System and method for non-invasive measurement of blood cell volume Description of an exemplary structure incorporating one of the teachings of the present invention will be presented below through discussion of its method for blood cell volume measurement . Fig. 17 shows an embodiment of the present invention. In this embodiment, the pulsating impedance and pulsating pressure are measured in a cavity surrounding a patient's finger. Although a finger has been selected as an exemplary body part to illustrate this embodiment, it is important to note that other body parts can be used. In addition, although Figure 17 illustrates some specific components, any electrode device, pressurization device, and other combinations have the same hair size. This paper size is applicable to the Chinese National Standard (CNS) A4 (210 X 297 mm). ) ---- II ------ 丨-丨 Order II -------- · * ^ (Please read the notes on the back before filling in this page) 577726 A7 ______B7___ V. Description of the invention () The device taught by Mingzhi can be used in this system to implement the hematocrit method of the present invention. A series of electrodes 10 are placed on the finger 1, where the external electrodes 100 are spaced as far apart as possible, and each of the internal electrodes 100 is connected to the closest external electrode 〇0 separated by about 5. 0 mm and as far apart as possible from each other, but this distance must be within the length of the finger 1. The external electrodes 100 are driven by an alternator 5 which can be set to transmit a fixed current at a frequency in the approximate range of 10KΗζ to 200KHz. The optimal frequency for this system is likely to be in the previously mentioned range 'to achieve the maximum current target without identifiable neuromuscular stimulation and no low phase between the current and voltage acting on these electrodes difference. Although the test results of one of the early prototypes of the present invention indicate that the 100K Η z system is suitable for achieving satisfactory results, another frequency system may produce a more practical implementation. The internal electrodes 10I are connected to the input of a high-impedance voltage amplifier 6, which senses the voltage between the electrodes. The alternator 5 and the amplifier 6 are both connected to a computing system 7 which combines these electronic signals with other signals from the pressure sensing device (described below) to calculate And display the blood cell volume. The computing system 7 also has the purpose of controlling the automatic operation of the measuring device. The detailed situation of the computing system 7 is not described in FIG. 17 or the description of the present invention, because any inclusion (31 paper standards are applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm)- ------------ Installation -------- Order --------- Line (Please read the precautions on the back before filling this page) 577726 A7 ______B7__ V. Description of the invention (but not limited) The structure of a personal computer type computer with an analog-to-digital converter and an output port control interface or an appropriate program for a special display will be sufficient to perform this function. A sealed pressure chamber 8 surrounds the finger, with a gas-tight, pressure-resistant seal at the proximal and distal ends of the finger. The seals are placed above the internal electrodes 101 or very closely adjacent to the internal electrodes 101. The first purpose of this chamber 8 is to contain air in the closed volume of the chamber surrounding the finger, so that when blood from the patient's circulating arterial system is pulsed into the finger, the There is a small increase in pulse pressure in the system 8. The second purpose of this chamber 8 is to accommodate an externally applied bias pressure which causes the blood vessels in the part of the finger enclosed by the chamber 8 to locally collapse. The local weakening of these blood vessels results in more blood flowing into the finger at each heart pulse. In sequence, the larger blood flow pulse system caused by the bias pressure causes a larger pressure pulse to occur in the chamber and a larger voltage pulse to occur between the internal impedance sensing electrodes 10I. . It should be understood that the electrodes 10 can be integrated with the cavity 8 or can be separated from the cavity 8 and can act on the finger independently because they are inserted into the cavity. A pressure transducer 9 is pneumatically connected to the pressure chamber 8 and electrically connected to the computing system 7 for sensing the bias pressure and the pulse wave pressure, whereby the blood volume of each pulse wave The system can be calculated 'and a signal for transmitting pressure to the computing system 7 ° is also pneumatically connected to the pressure chamber. 8 is a bias pressure source 5 4 and 32. This paper size applies to China Standard (CNS) A4 specification (210 X 297 mm) ----- I ---------- I -----order ---- I ---- line (please read the back first Please note this page, please fill in this page) 577726 κι __Β7 ______ V. Description of the invention () A solenoid valve controlled by the computing system 5 5 ° This valve 5 5 allows the bias pressure source 5 4 to flow out Sufficient flow to reach the intended bias pressure, and then closed to lock the bias pressure inside. The pressure source 54 can be any structure having a high pressure capable of supplying air at a pressure higher than the surrounding atmospheric pressure and about 20 OmmHg. The level of the pressure supply can be selectively controlled by the computing system 7. A correction device 5 7 is also connected to the pressure chamber 8 '. The correction device 5 7 can inject a dose of an accurately known volume of air into the chamber 8 to correct the pressure change. The pressure change represents a The given volume. The correction device 5 7 can be as simple as a small-calibrated medical syringe, as shown in FIG. 17, it can be manually operated, or it can be a more complicated device, with the computing system 7 The control can produce accurate volume pulses of the same size as the heart pulse for dynamic correction. A measurement method Those skilled in physiological impedance measurement know that each time a heartbeat is pulsed into a blood line in a tissue space between a pair of sensing electrodes, the pulses in the impedance decrease. You can observe the change in impedance versus time caused by the heartbeat on an oscilloscope to get a picture called the impedance waveform. When this waveform is inverted and scaled appropriately, the waveform has a shape that is approximately the same as the change in blood volume versus time caused by the heartbeat. The similarity of the waveform implies that the change in impedance is due to a change in volume and can be used to measure the change in volume. 33 This paper size applies to China National Standard (CNS) A4 specification (210 X 297 mm) ------------------- line (please (Please read the notes on the back before filling this page) 577726 A7 __B7_ V. Description of the invention () An equation about the volume change △ V versus the impedance change △ Z has been developed and has been recorded in Geddes and Baker "Principles of Applied Biomedical Instrumentation," second edition, John Wiley and Sons, New York (1975). The equation is: AV = pL2AZ / Z〇2 (1) where △ V is the change in blood volume at any point in time, △ z is the change in impedance at the same point in time, and P is the resistivity of blood , L is the distance between the impedance sensing internal electrodes 10 I, and Z is the baseline impedance at the beginning of each pulse. The aforementioned equation (1) can be rearranged to solve the resistivity p, and we know that it depends on the blood cell volume: p = avz〇2 / l2az (2) Now, we observe that it is used to calculate P (that is, △ V , Z Q, L and △ Z) can be measured in the system described previously. Specifically, ΔV is measured through the pressure transducer 9 as the volume change in the pressure chamber 8, Z0 and ΔZ are measured through the voltage amplifier 6, and L is sensed in these internal The distance measured between the electrodes 101. With P, blood cell volume can now be calculated directly. In the paper "The specific Resistance of Blood at Body Temperature," Geddes and Sadler, Medical and Biological Engineering, 11: 336 ~ 339 (1973), Geddes and Sadler experimentally derive and report blood resistance in simple algebraic and exponential form. The number between the rate p and the blood cell volume Η 34 t The paper size is applicable to the Chinese National Standard (CNS) A4 specification (210 X 297 mm 1 " " " -------------- --- II Order -------- • line (please read the note W on the back before filling out this page) 577726 A7 _B7____ V. Description of the invention () Learn the relationship. The algebraic form is: P = (5 8 +. 4 3 5 Η) / (1-· 0 1 Η) (3) where Η is the percentage of blood cell volume. This equation can be solved by ρ, such as: H = (^ -58) / (. OlP + -4 35) (4) Applying this last equation (4), using P 値 determined from the impedance and volume measurements, we now get Η, which is our original purpose. In order to obtain the greatest accuracy in the application of the equations shown above, it is necessary to perform a very accurate measurement of blood volume change (ΔV). This is achieved by comparing the pressure change inside the chamber 8 on the finger to the pressure change caused by a known change volume imposed by the correction source 57 in the computing system 7. A correction source 5 7 controlled by the computing system 7 can be adjusted to produce precisely controlled volume changes that have approximately the same magnitude as the volume changes produced by the blood pulses. This calibration method should produce the most accurate hematocrit measurement. The accuracy of both the impedance and the direct volume measurement can be increased as needed by creating greater arterial pulsation in the finger. The application of a bias pressure in the chamber 8 has been experimentally shown to increase the pulse volume by a factor of ten, wherein the magnitude of the bias pressure applied in the chamber 8 is higher than the A substantial part of the systolic blood pressure of a finger is preferably equal to the average arterial blood pressure of the finger. The increase in the volume of the pulse wave achieved in this way increases the accuracy of the measurement of the blood cell volume. The paper size is in accordance with the Chinese National Standard (CNS) A4 specification (210 X 297 public love) -------- -------- I ---- Order --------- line (please read the precautions on the back before filling this page) 577726 A7 _B7_ V. Description of the invention () By improving these signal-to-noise ratios that will reach both the impedance and pressure bands of the computing system 7. More importantly, the arterial component of the pulse wave volume becomes larger than the pulsating volume of other blood vessels (such as microvessels) related to the finger, which makes the derived blood cell volume closer to a real trance. Pattern recognition algorithms Several experiments have determined that the impedance pulse wave in a finger is usually very weak compared to the pressure pulse wave, and the two pulse waves are measured simultaneously in the application of the present invention. When measuring the impedance pulse by measuring the voltage on the internal electrode group pair 10 I, it has been found that a large noise voltage often exists, which obscures the signal and makes the measurement The accuracy is reduced. In this case, it is customary for us to use an analog filter circuit to filter the noise signal, or instead use a digital filtering algorithm, which is executed in the computing system 7. One type of digital filter that may be used is based on the assumption that the general shape of the impedance pulse waveform and the pressure pulse waveform are the same. When forming this hypothesis, we know that the two signals must have. The same frequency component. The fact that the two signals have the same shape and frequency content allows proper filtering algorithms to be used which can be matched in the time domain or frequency window filters in the frequency domain, where the best The filtering parameters are derived from the characteristics of this fairly clean pressure signal waveform. In other words, the filtering algorithm uses the fairly clean pressure signal waveform as a template for the rather mixed impedance signal waveform to filter out noise. 36 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) '" ------------- installation -------- order ---- ----- Line (please read the precautions on the back before filling this page) 577726 A7 __B7_ V. Description of the invention () Another example of this measurement method is in the blood cell volume described by Kaminsky with reference to the '808 patent The original method of decision was susceptible to a number of restrictions, which were caused by the very minute blood volume pulses that occurred in the finger and the noise impedance signals. The application of the bias pressure method for increasing these pulses (as taught by the present invention) and the application of the filtering method described in the previous paragraph improve the accuracy of this dual-frequency method and any other multi-frequency method, The multi-frequency method depends on the blood pulse wave to discriminate the impedance component of the arterial blood. Any of the following implementation systems are considered to be within the scope of the present invention. For example, a pressure chamber (or a ferrule) connected to an electrode array is used to measure the pulse volume, and a pressure pulse signal is obtained for use. Either derive appropriate filtering parameters or apply a bias pressure to increase the arterial pulsation. Applying the above equation (2) to two different frequency systems allows us to obtain the following ratio 値: (Pl / ph) = (Zl2 / Zh2) · (AZh / AZl) (5) where Pt is the Blood resistivity of the lower frequency of the two frequencies, PH is the blood resistivity of the higher frequency of the two frequencies, Zt is the baseline impedance of the low frequency, Z Η is the baseline impedance of the high frequency, △ Z Is the timely impedance change of the high frequency at a certain point, △ ZL · is the timely impedance change of the low frequency at a corresponding point. Please note that equation (5) provides the different advantages of eliminating these geometric coefficients ΔV and L. By selecting a high frequency between 1MΗ ζ and 1 ΟΜΗ ζ, the blood cell volume system can be appropriately expressed as a (P t / p 37 This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 Mm) ----- II —------------- Order -------- (Please read the notes on the back before filling this page) 577726 A7 _ _____B7___ 5 , Description of the invention () η) function. The measurement of (obtained from equation (5) can be expressed by the measurable voltage and current as: (Pl / ph) = (AVo 1 tn / AVo 1 tL) · (Vo 1 tL2 / Vo 1 tH2 ) (Ih / Il) (g) where Δν〇11 :, νο11 :, and i respectively represent the measurable pulse voltage, baseline voltage, and current. Because I Η and I t are controllable in the instrument The fixed current source is placed below, so equation (6) can be simplified as: (pl / p H) = c · (Δν〇1 tH / VH2) / (A Vo 1 tL / Vo 1 tL2) (7) where C = I h / I 4 is a known constant. A living bottle-type one (ρρ Ρ) for linking (P Η) with the blood cell volume is proposed as follows, which is, for example, by Geddes and Sadler ("The Specific Resistance of blood at Body Temperature," Med.  and Biol.  Eng. , 336-339, May, 1973) Publisher: (pl / pp) = [l + (f — 1) · Η] / (1 Η) (8) where PP is the resistivity of plasma and f is Is the shape factor (as measured by Geddes and Sadler when the direction of human red blood cells is random. 75). The effect of frequency on blood resistivity is explained by noting that the red blood cell membrane acts as an insulator at low frequencies, causing p l to increase predictably as the volume of blood cells increases. However, at frequencies of approximately 10 MHz and higher, the 38 paper sizes apply the Chinese National Standard (CNS) A4 specification (210 X 297 mm) III — — — — — — — — IIIIIII Order — — — — — — — — (Please read the precautions on the back before filling this page) 577726 A7 __B7____ V. Description of the Invention () The red blood cell membrane reactance is actually eliminated, which causes the fluid in the cell to participate in the blood completely. Impedance measurement. This situation reduces the sensitivity of P η to the blood cell volume Η. Assuming that the resistivity of the intracellular fluid (p RBS) does not deviate slightly from p P, the sensitivity of P η to the volume of blood cell Η will be practically eliminated at a frequency of 10 MHz or higher.

Fricke also published in "A Mathematical Treatment of the Electric Conductivity and Capacity of disperse System," The Physical Rev ·, Vol. 24, 2nd Series, Jul.-Dec ·, 1924 for expressing PH as pP, f, H And the theoretical basis of a function, I extracted it as: (Ph / pp) = {1 + [(((af (e_bx-c)) / (1-x)) -1] · Η} / {1 + [((Af (e_b x- c)) x / (l — x)) — 1] Η} (9) where x is the admittance ratio of red blood cells to plasma 値, and a, b, and c are Are constants derived from the curves in Figure 3 of Fricke, where a = 1.56, .b = 1.02, and c = 0.36 (in accordance with Geddes and Sadler, f is used instead of when χ = 〇 Hour One (X) 値). Note that when x = 〇, equation (9) is simplified to equation (8), and when X approaches 1, the equation (9) is simplified to 1. It should also be noted that equation (9) applies to any frequency at which x 値 (currently the definition includes the effect of the membrane on the admittance of red blood cells) can be measured. Now, by dividing equation (8) by equation (9), the ratio pl of pl / ρ Η can be determined, which is: 39 ------------- 装 ----- --- Order --------- line (please read the notes on the back before filling this page) This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) 577726 A7 B7 5 Description of the invention () {P h / ph) = [(l + (f-1) H) / (1-H)] {l + [((af (e'bx-c)) x / (lx))- 1] H} / {l + C ((af (e-bx-c)) / (lx))-l] H} (10) Figure 18 is a block diagram showing a dual-frequency embodiment of the system. The waveform generator 100 for 100 kHz and 100 MHz is a laboratory instrument, although such signals are, of course, typically from an internal oscillator of a blood cell volume measuring instrument used in this field. Produced. An exemplary host computer 102 is a fully equipped system compatible with IB M, which is a general-purpose laboratory data processing software, which is custom-made based on the calculations required for such research. . In this field, the host computer 102 will typically include a dedicated processor with dedicated software or firmware. The computer 102 is equipped with a multi-channel analog-to-digital converter 104 for monitoring a patient's physiological signals. A finger 106 or a calibrated resistor string (for experimental purposes) is driven by a fixed amplitude current source 108 at both low and high frequencies. The mixed voltage is selected by the internal electrode pair (see FIG. 17), amplified by a sense amplifier 1 1 0, and then separated into two by a complementary pair 1 1 2 of a low-pass and high-pass filter. Signals. Then, the separated signals at two frequencies are rectified by a rectifier 1 1 4 to provide a direct current signal with pulse waves superimposed on the direct current heights at the baseline heights. Then, by using a pulse wave separator 1 1 6 from the pulse wave-containing 40 ------- I ----- install -------- order -------- -Line (please read the precautions on the back before filling this page) This paper size applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) 577726 A7 _ B7 _ V. Description of the invention Pass the filtered signal to separate the pulse waves from the baseline voltages. The pulse trains are then magnified to the extent that they can be seen on an oscilloscope display on the computer 102. The computer's 102 series monitors four signals: two baseline signals and two pulse signals. Via these signals, the calculation of the blood cell volume is performed using the equations described above. Automatic calibration-An automatic calibration system can improve the accuracy of the measurement of blood cell volume, which is achieved by compensating for drift in the electrons, by periodically measuring the high-frequency and low-frequency current ratios, and the circuit gain ratio . In order to understand the correction process, the equation (7) is rewritten as: (pL / pH) = C, • (△ Volt, / Δν〇1 t L,) (V o 1 tl, VV o 1 t h '2 ) (11) where the coefficient c 'is an instrument correction coefficient. The apostrophes on these voltage parameters indicate a voltage measurement that is the opposite of the actual voltage present at the measurement location. Therefore, C '(including the fixed current ratio IH / I k and the circuit gain ratio) becomes: C' = (Ih / Il) / (Ah / Al) 2 (DAl / DAh) (12) where Ah and Al are respectively Is the net amplification factor of the channel, and D Ah and DAL are the net pulse amplification factors of these frequencies, respectively. To the extent that the net amplification factors are linear (which includes the sense amplifier 1 1 0, the filter 1 12 and the rectifier 1 1 4), the system can be adjusted by a single adjustment of the correction coefficient C ' And was corrected. One to obtain 41 paper sizes applicable to China National Standard (CNS) A4 specifications (210 X 297 mm) --------------------- Order ------ --- Line (please read the precautions on the back before filling this page) 577726 A7 __B7_____ V. Description of the Invention () The method of C '値 uses a series of three resistors. The manual mode or the switch mode is connected to the appropriate position of the finger. In this case, the resistor string (shown in FIG. 19 as shown in FIG. 19) is placed in the circuit. Preferably, the three resistors in the string are approximately the resistance of a body part (for example, a finger) to be measured for blood cell volume. For example, each of these resistors may have a resistance of about 5 OO Ω or about 5 6 Ω. Please refer to FIG. 18 again. The fixed amplitude current source 108 pushes the fixed current at two frequencies through the resistors 120 (located in FIG. 19), and the sense amplifier 110 is driven from The two ends of the center resistor receive differential signals. In order to generate a pulse wave similar to the impedance pulse wave caused by blood in the finger, a fourth resistor 1 2 2 (which is larger and variable) in FIG. 19 may be parallel to the central resistance The way the device is placed and can be changed by certain mechanisms. An embodiment of the parallel resistor 1 2 2 is a semiconductor photoresist 1 2 1 enclosed in an opaque cylinder. The opaque cylinder also includes a light emitting diode 1 2 3. The current driven to the diode 1 2 3 will be changed in the shape of the arterial impedance pulse wave of the signal generated by the computer 102. The structure and method of this pulse wave ensure that both the basic impedance and the impedance pulse wave have the same amplitude at high and low frequencies. Once the equality of the basic and pulse impedances is ensured, it is possible to measure all the parameters in equation (1 1) using (pt / pH) = 1.0 on the same electronic device as the finger parameters. , And by the following equations, the paper size of this paper applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) -----— — — — — — — — — I --- 11— Order- --- IIII (Please read the precautions on the back before filling this page) 577726 A7 ^ __ B7__ 5. Description of the invention () Solve C ': C, = (Δ V ο 1 t L, / Δ V ο 1 t) (V ο 1 th, VV ο 1 t lj 2) (13) The reader should note that various mathematical terms (such as product and ratio) appear in certain items in the scope of this additional patent application. The inventor has used the term "effective" in the context of a patent application in conjunction with these mathematical terms to clarify that the present invention includes, among other things, all uses of the variables and constants described herein to calculate Hematocrit is within the scope of systems and methods. The present invention is not limited to any specific system or method for linking the blood cell volume to these variables and constants, nor is it limited to any specific calculation sequence and form. In other words, the present invention is encompassed within the scope of all systems and methods that use the variables and constants described herein to calculate the volume of blood cells, and it uses the methods described herein to "effectively" calculate the volume of blood cells, regardless of The actual method of performing calculations. Similarly, one should understand that phrases such as "effectively determining one-by-one" mean that the act of including (rather than excluding) actually determining one-by-one is determined. Although the invention has been described with reference to specific embodiments, the invention is not limited to these described embodiments. For example, one should understand that the signal enhancement effect described above can be achieved by any of the embodiments disclosed herein when combined with the application of stress to fingers or other body parts in the test. Accordingly, the present invention is limited only by the scope of these additional patent applications, which are included in the scope of all equivalent devices and methods that operate in accordance with the principles of the invention as described. 43 This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) --- III I--I ----------- 1 order ------- (please first (Read the notes on the back and fill out this page)

Claims (1)

577726 A8B8C8D8 6. Application for Patent Scope 1. A device for non-invasively measuring the volume of a patient's blood cells, which includes: a first electrode pair, which is configured to be used to at least partially contact the One of the patients is a body part whose blood cell volume is to be measured. The first electrode pair may be connected to an electrical current source. A second electrode pair is configured to be used to at least partially contact the intended electrode. For measuring a blood cell volume of a body part, the second electrode pair may be connected to an electrical impedance measuring device; and a pressurizing member configured to externally apply pressure to at least the body part portion. 2. The device according to item 1 of the scope of patent application, wherein the electrical impedance measuring device is configured to measure the electrical impedance of at least one frequency between the second pair of electrodes on the body part. 3. The device according to item 1 of the scope of the patent application, wherein the pressing member is configured to be used to at least partially receive the body part. 4. The device according to item 1 of the scope of patent application, wherein the pressure-increasing component is combined with a pressure-measuring device, and the pressure-measuring device is configured to detect a change in pressure. 5. The device according to item 4 of the scope of the patent application, wherein the pressure measuring device is configured to detect a pulsating change in pressure in the pressurizing member. 6. The device according to item 3 of the scope of patent application, wherein the pressure measuring device comprises a pressure ferrule. 7 · The device according to item 3 of the scope of the patent application, where the pressure ____1___ This paper rule i applies the Chinese National Standard (CNS) A4 specification (210 X 297 mm) — -......... ....... install .........- Order ...... ... line (please read the precautions on the back before copying this page) 577726 A8B8C8D8 VI. Patent application scope; the force measuring device includes a pressurized chamber, which includes: at least partially hollow An external rigid element; an internal flexible element disposed inside the rigid element, the flexible element being partially sealed against the rigid element to be between the rigid element and the flexible element Forming a pressurized pouch, the flexible element includes a socket that is configured to receive at least one 15 minutes of a body part. 8. The device according to item 7 of the scope of patent application, wherein the socket comprises two open ends. 9. The device according to item 7 of the scope of patent application, wherein the socket comprises a closed end. 10. The device according to item 7 of the scope of patent application, wherein once the pressure is introduced into the pressurized bladder, the flexible element applies pressure to a body part arranged in the socket. 1 1. The device of claim 1, wherein at least one electrode system of the first and second electrode pairs includes an elongated element configured to be contacted with the body part. 1 2 · The device according to item 11 of the scope of the patent application, wherein at least one of the electrodes further comprises another elongated element which is configured to be connectable to the electrical current source. 1 3. The device according to item i 2 of the scope of patent application, wherein the at least one electrode is substantially linear. ~ 1 4 · According to the arrangement described in item 12 of the scope of the patent application, it is advisable that the at least-art department is Fina. _ ^ __2 Jade paper size applies to China National Standard (CNS) A4 (210 X 297 mm)-......... I ---------------- --------------- Order ------------ line (please read the precautions on the back before f- · this page) 577726 SI VI.Application Scope of patent. 1 5 · The device according to item 1 of the scope of patent application, further comprising at least one connector configured to connect at least one electrode to an external electronic component. 16 · The device according to item 15 of the scope of patent application, wherein the at least one connector is configured to be used for connecting at least two electrodes to external electronic components. [17] The device according to item 15 of the scope of patent application, wherein the at least one connector is further configured to be used to connect the pressurizing member to a pressure supply and control device. [18] The device according to item 15 of the scope of patent application, wherein the at least one connector is further configured to be used for connecting the pressure member to a pressure source. 19 · The device according to item 1 of the scope of patent application, further comprising a substrate, the substrate at least partially carrying at least two electrodes. 2 0. The device according to item 19 of the scope of patent application, wherein the base comprises a pressurizing member configured to be used to externally apply a pressure to at least a part of the body part. 2 1 · The device according to item 19 of the scope of patent application, wherein the substrate is flexible. 2 2. The device according to item 19 of the scope of the patent application, wherein the substrate carries at least one electrode of each of the first and second electrode pairs. 2 3. The device according to item 19 of the scope of the patent application, wherein the substrate carries each electrode of each of the first and second electrode pairs. 3 ^ The paper is again applicable to China National Standard (CNS) A4 (210 X 297 mm) '..... I ... .............. Order ---------------- line (Please read the precautions on the back before writing this page) 577726 098855 ABCD VI 2. The scope of patent application 24. The device according to item 1 of the scope of patent application, further comprising at least one holding member, which is configured to be used to hold at least one electrode on the body part. 25. The device according to item 24 of the scope of patent application, wherein the at least one holding member comprises at least one adhesive material and a holding sleeve configured to receive one end of the at least one electrode A socket and electrode end configured for interconnection with each other, and a material that remains substantially deformed. 2 6 · —A device for non-invasively measuring a patient's blood cell volume, comprising: a first electrode pair configured to be used to at least partially contact one of the patients The first electrode pair can be connected to an electrical current source for a body part of the blood cell volume to be measured; a second electrode pair is configured to be used to at least partially contact the blood cell volume to be measured. For a body part, the second electrode pair may be connected to an electrical impedance measuring device; and at least one holding member configured to be used for fixing at least one electrode to the body part. 27. The device according to item 26 of the scope of patent application, wherein the at least one holding member comprises an adhesive material on at least a part of the at least one electrode. 28. The device according to item 26 of the scope of patent application, wherein the at least one holding member includes a holding sleeve on the at least one electrode, and the holding sleeve is configured to be used for receiving and holding. _4_ of this at least one electrode This paper size applies to China National Standard (CNS) A4 (210 X 297 mm) " " " ........ ......... install -.............. order line (Please read the note on the back first Matters are reproduced on this page) 577726 Stuffing C8 D8 6. One end of the scope of patent application. 29. The device according to item 26 of the scope of patent application, wherein the at least one holding member includes a socket on the at least one electrode, and one end portion of the at least one electrode is configured to be used with the at least one electrode. The sockets are connected to each other. 30. The device according to item 29 of the scope of patent application, wherein the end portion includes: a holding area, each holding area having a holding width larger than that of one of the sockets; and a necking A region is provided adjacent to each holding region, and the necked region has a necked width which is at most approximately equal to the width of the socket. 31. The device according to item 26 of the scope of patent application, wherein the at least one holding member comprises a material made of at least a part of the at least one electrode, and at least a part of the at least one electrode is substantially kept deformed so that At least the part can be held on the body part. 32. The device according to item 26 of the scope of patent application, wherein the at least one holding member includes a pressurizing member. 3 3 · —A device for non-invasively measuring a patient's blood cell volume, comprising: a first electrode pair 'which is configured to be used to at least partially contact one of the patients The first electrode pair can be connected to an electrical current source for a body part of the blood cell volume to be measured; a second electrode pair is configured to be used to at least partially contact the blood cell volume to be measured. For body parts, this second electrode pair can be connected 5 (Please read the precautions on the back before writing this page}: Installation, ι? Τϊ ^ Paper size applies Chinese National Standard (CNS) A4 (210 X 297) (Centi) 577726 B8 C8 D8 6. Application for patent scope. Connected to an electrical impedance measurement device; and a substrate that carries at least two electrodes. (Please read the precautions on the back before writing this page) 3 4 · The device according to item 33 of the scope of patent application, wherein the at least two electrode systems carried by the substrate are adjacent to each other. 3 5 · The device according to item 33 of the scope of patent application, wherein the substrate comprises a Pressure components 3 6 · According to the application Please refer to the device described in item 33 of the patent scope, wherein 'the substrate contains some amount of adhesive material adjacent to at least one of the at least two electrodes. 3 7 · The device described in item 33 of the scope of patent application , Wherein the substrate is flexible. 3 8 · The device according to item 33 of the scope of the patent application, wherein the substrate carries at least one electrode of the first and second electrode pairs. 3 9 · According to the application The device described in item 33 of the patent scope, wherein the substrate carries each electrode of the first and second electrode pairs. 6 This paper size is applicable to China National Standard (CNS) A4 (210 X 297 mm)