JPH08182665A - Blood analysis object measuring device - Google Patents

Abstract

PURPOSE: To provide a new blood-gas continuously measuring device which facilitates the grasp of the targeted organ condition, by providing direct blood- gas continuous information at a local site of a living body. CONSTITUTION: Blood-gas information which is detected both by a retained needle type probe 10 which is used in arterial vascular side and by a catheter type probe 20 which is used in venous vascular side is arithmetically operated by a control part 40 and the operated result is displayed on a display part 50. For example, values of pH, PO2 , PCO2 , Be, HCO3 <-> of each probe and futhermore, a difference, ratio change of the ratio or the like of each parameter are displayed on the display part 50, by comparing and arithmetically operating the informations from two probes 10, 20 on the operation part 40.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for measuring an analyte in blood and a method thereof, for example, pH and P in human blood.
The present invention relates to a blood analyte measuring device and method for measuring multiple factors such as O ₂ and PCO ₂ .

[0002]

2. Description of the Related Art In the field of current medical care, various ME devices such as life support have become multifunctional and high-performance, and along with this, the body is required to perform quick treatment according to the ever-changing pathological condition. Real-time monitoring of functional parameters has become important. Among the parameters to be monitored, those related to blood are also important, and examples thereof include the pH of blood, the state of PO ₂ and PCO ₂ . Various techniques have been proposed to date for the purpose of monitoring these parameters. In recent years, as a particularly promising technology,
A continuous blood parameter measuring device based on a fluorescent substance that is sensitive to an analyte in blood and an optical fiber that transmits the information has been introduced.

A conventional blood gas test is performed in vitro.
It is carried out intermittently, and blood is usually collected from the radial artery, brachial and femoral arteries with a heparinized syringe, ice-cooled and transported to a laboratory for measurement. Therefore, it usually takes 10 to 20 minutes from blood collection to result reporting.

The measurement principle in the conventional blood gas measuring device is based on the light emission phenomenon of the dye fluorescent substance, in addition to measuring the potential and the like by the electrodes. The phosphor is supplied with light having an excitation wavelength peculiar to the phosphor from the main body of the device through the fiber, and changes its emission intensity depending on the concentration of the analyte in blood. This fluorescent signal is taken into a photodetector in the main body of the device through the fiber. Since the fluorescence signal is expressed as a function of the analyte concentration, the concentration of the analyte can be quantified by detecting the fluorescence signal.

The blood gas data measured as described above provides useful information on the physiological processes shown below. That is, systemic metabolism, alveolar ventilation, oxygenation,
Acid-base equilibrium.

However, in the above-mentioned conventional blood gas measuring device, since it took at least about 10 minutes from blood collection to result reporting, real-time information could not be obtained.

On the other hand, an apparatus for continuously measuring blood gas with an indwelling needle type probe has also been developed in recent years, which has enabled continuous real-time measurement of blood gas.

[0008]

However, the blood gas information measured by the blood gas measuring device of the above-mentioned conventional example is only intermittent or relates to the whole human body.

[0009] In order to identify a lesion in a human body and perform a treatment according to a pathological condition that is constantly changing, a lot of detailed biometric information is required. For example, it is necessary to grasp more direct information about the local state of the living body such as the brain, liver, heart, kidney, etc., in an easy-to-understand manner. That is, it is desirable to continuously obtain accurate and real-time information in the local area of the living body.

The present invention has been made to solve the above-mentioned problems, and it is an object of the present invention to provide a blood analyte measuring device capable of continuously measuring accurate and real-time blood gas information locally in a living body. To aim.

[0011]

In order to achieve the above-mentioned object, the present invention comprises the following constitutions.

That is, a device for measuring an analyte in blood in a living body, which comprises a first sensor probe placed in an artery, a second sensor probe placed in a vein, and the first sensor. It is characterized in that it has a probe, a calculation means for calculating a signal detected by the second sensor probe, and a display means for displaying a calculation result by the calculation means.

For example, the display means displays the calculation result by the calculation means as information on an organ existing between the first sensor probe and the second sensor probe.

For example, the second sensor probe has a catheter shape which can be inserted into a desired position in the body.

For example, it is characterized in that the arithmetic means can perform arithmetic only with the signal detected by the first sensor probe.

For example, the arithmetic means is characterized in that it is possible to perform arithmetic operation only with the signal detected by the second sensor probe.

For example, the first sensor probe can be placed in a vein.

For example, the second sensor probe can be placed in an artery.

For example, each of the first and second sensor probes transmits the light emission intensity or the extinction speed as optical information, and the sensitive means for changing the light emission intensity or the extinction speed according to the concentration of the analyte. And a transmission means for

For example, the analyte is pH, P
It is characterized by being O ₂ and PCO ₂ .

[0021]

With the above structure, the first sensor probe is placed in the artery, and the second sensor probe is placed in the vein serving as the main trunk of the organ. The signal detected by the sensor probe can be calculated by the calculating means, and the calculation result can be displayed on the display means as information on the organ. Therefore, the operator can obtain a unique effect that the information of the blood analyte in the organ can be continuously known in real time.

Other features and advantages of the present invention will become apparent from the following detailed description, taken in conjunction with the accompanying drawings, which illustrate by way of example the principles of the invention.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

The appearance of the blood gas measuring device in this embodiment is shown in FIG. In FIG. 1, 100 is a measuring unit,
Each information measured by the measuring unit 100 is sent to the control unit 40 which is the main body of the blood gas measuring device, and is displayed on the display unit 50 as blood gas information by a predetermined calculation process described later. Therefore, the operator can detect the local state of the subject currently being measured from the blood gas information displayed on the display unit 50. Note that the control unit 40 and the display unit 50 may of course be integrated.

The measuring section 100 has two probes.
Reference numeral 10 is an indwelling needle type probe mainly used on the arterial blood vessel side, and 20 is a catheter type probe mainly used on the venous blood vessel side. As will be described later in detail, each of these probes has an optical system for appropriately converting the light emitted from the light source provided inside the control unit 40 into an appropriate emitted light, and a light receiving system provided at the probe tip. are doing. Further, although the probe 10 is mainly used on the arterial blood vessel side, it can also be used on the venous blood vessel side. Similarly, the probe 20 can be used for arteries.

The indwelling needle type probe 10 and the catheter type probe 20 are connected to the respective optical fiber connectors 31 and 32, and the connectors 31 and 32 are detachable. Incidentally, the connectors 31 and 32
Are the same, so it is possible to mount the probes 10 and 20 interchangeably. The cords connecting the connectors 31 and 32 and the control unit 40 are unified into a Y-shape at 30 cm from the connectors 31 and 32 (30).

Since the blood gas measuring apparatus of this embodiment is for obtaining local blood gas information of the human body, the indwelling needle type arterial probe 10 is placed on an artery, preferably on the peripheral side of the radial artery or the like. It is placed in the artery. It is preferable in the measurement that the artery probe 10 is placed in the artery closest to a predetermined organ, but since it may cause thrombus formation and accompanying occlusion, it is placed in a peripheral artery such as a radial artery. Is more preferable. On the other hand, the catheter-type vein probe 20 is placed so that its sensor portion is located at a site as close to the organ as possible in the venous system serving as the main trunk of the target organ. Each probe is connected to the control unit 40, and information obtained from each probe is compared and calculated as described below and displayed on the display unit 50 such as a monitor.

The shape of the indwelling needle type arterial probe 10 is shown in FIG. Arterial probe 10 has a diameter of 1.0 mm
Hereafter, the length is 10 cm or less, and preferably the diameter is 0.5.
The length is 5 mm or less and the length is 5 mm or less. Further, it is constructed so that it can be inserted and fixed in a general indwelling needle guide. The probe 10 has a structure that is treadless and does not have a sharp portion in order to reduce damage to the blood vessel wall. Further, in order to cope with indwelling for a long time, the blood contact portion is subjected to an antithrombotic treatment such as heparin coating.
The other end of the probe 10 is connected to the optical fiber connector 31 shown in FIG.

The shape of a catheter-type vein probe 20 used for the heart, liver, kidney and lung is shown in FIG. The vein probe 20 preferably has a diameter of 1.0 to
3.0 (more preferably 1.7 to 2.3 for adults)
mm, effective length 120 cm or less, and the surface is subjected to an antithrombotic treatment method, for example, heparin coating.

The catheter-type vein probe shown in FIG. 3 has an S-curve shape with the tip of about 1 cm bent within a range that does not form an acute angle, and conforms to actual acute-angle blood vessel travel. It has become a thing. The shape of the catheter may be, for example, a J curve or a Z curve. Then, in order to measure the insertion length in the body, that is, 10 cm from the tip, in the indwelling part of the catheter
A mark is printed for each unit.

A blood sampling and blood pressure measuring port 68 is provided at the tip of the catheter. Further, only when the lung is targeted, a balloon mechanism 69 for guiding the tip of the catheter onto the venous blood flow and guiding it near the target position in the body.
May be provided. FIG. 4 shows how air or carbon dioxide gas is injected into the balloon mechanism.

Further, reference numeral 65 denotes a blood gas sensor opening, which exposes a sensor portion described later. Reference numeral 66 is a contrast agent injection port, and 67 is an infusion agent injection port.

The catheter material is soft vinyl chloride,
Bismuth trioxide is kneaded to make it easier to confirm the position during contrast enhancement. When the venous indwelling probe 20 is used for the brain, the probe having the same shape as that of the indwelling needle type probe 10 is preferably used in combination and placed in the jugular vein.

As shown in FIG. 5, the catheter-type vein probe 20 shown in FIG. 3 has a blood gas measuring lumen 51, a blood collecting lumen 52, and a blood pressure measuring lumen 5.
2 ', infusion lumen 53, contrast agent injection lumen 5
4, a balloon air injection lumen 55 and a temperature or flow velocity measurement lumen 56. The blood pressure measuring lumen 52 'is common to the blood collecting lumen 52 and is used as necessary. The lumens are collected in the probe 20 through the manifold 60, the blood gas measuring lumen 51 is connected to the optical fiber connector 32, the temperature or flow velocity measuring lumen 56 is connected to the thermistor connector 63, and the other lumens are connected to the luer connector. It is connected to 62.

Hereinafter, the above-mentioned two probes 10 and 2 will be described.
The basic configuration of 0 is shown in FIG. 6 and will be described.

The basic constituent elements of the sensor in the above-mentioned two probes are common to the moving / vein, and as the basic elements, dye fluorescence that is emitted or quenched by protons in blood, PO ₂ , and PCO _2. Including the body.

FIG. 6 shows a detailed structure of the probe 10, for example. The probe 10 has a diameter of 0.5 mm or less, and is provided with a pH probe 11, a PO ₂ probe 12, and a PCO ₂ probe 13 which are optical fibers inside. These three
The fiber probe of the book is integrated as the probe 10 by being covered with the outer layer film 14.

In the pH probe 11, 1-hydroxy-3,6,8-pyrenetrisulfonic acid is provided as the pH sensitive phosphor 17, and the PO ₂ probe 12 and PCO ₂ are provided.
In the probe 13, the oxygen-sensitive phosphor 16 contains a tris (2,2′-bipyridine) ruthenium (II) complex. These materials are fixed in a suitable matrix and each exposed fiber optic probe 1
The cores 1 to 13 are wound around and fixed to each fiber end.

Further, the reflector 15 is mounted on each fiber probe in order to efficiently transmit the fluorescence emitted in all directions by the above-mentioned phosphors to the control section 40. In the reflector 15, an epoxy adhesive is mixed with an appropriate amount of a reflective substance, and the mixture is applied to the tip of the matrix and cured. TiO ₂ powder is preferably used as the reflective material.
The plurality of fiber probe groups are covered with a polymer film 14 having a controlled pore size that is permeable to blood gas such as oxygen and protons. The polymer film 14 is preferably a polyethylene porous film or a silicon-based material. Further, the probe 20 can be configured, for example, by inserting into the blood gas measurement lumen 51 a probe having a structure in which three fiber probes as shown in FIG. 6 are covered with an exterior.

As described above, each phosphor is directly or indirectly fixed to the tip of the optical waveguide (optical fiber) of each fiber probe, and the other end of the optical waveguide is connected to the controller 40. There is. Appropriate excitation light is given to the phosphor from the control unit 40 through the optical fiber, and the light emitted from the phosphor is transmitted to the control unit 40 through the same fiber. Therefore, it is desirable that each fiber probe has a structure of a reflector, a phosphor, and an end of the fiber, rather than the end thereof. One optical fiber is basically used for each of pH, PO ₂ , and PCO ₂ . The arterial / venous probes 10 and 20 in the present embodiment have the sensor configuration as shown in FIG. 6 described above, and the emission and extinction intensity of each phosphor is measured in each probe. The intensity of light emission / quenching by each phosphor is pH in blood, PO ₂ , PC
Since it can be related to O ₂ , by measuring the intensity in the apparatus of the present embodiment, the blood pH, P
O ₂ and PCO ₂ can be monitored.

As described above, the probes 10 and 2
0 can detect pH, PO ₂ , and PCO ₂ in blood by the sensor configuration shown in FIG. 6 at the tip thereof. The detected information is the optical fiber probes 11 to 13.
Is transmitted to the control unit 40 via the information transmission medium. Hereinafter, an example of the arithmetic processing in the control unit 40 will be described.

The control unit 40 in this embodiment calculates the following items from the information from the probes 10 and 20.

First, in the control unit 40, an arterial probe
PH obtained from 10, PO₂, PCO₂, BE, HCO
₃ ^-Parameter information of pHat, PO respectively₂at, P
CO ₂at, BEat, HCO₃ ^-and at the same time
From the valve 20, pHve, PO₂ve, PCO₂ve, BEve,
HCO₃ ^-Suppose ve is obtained. Then, in the control unit 40,
Each parameter information from these two probes is compared and presented.
As a difference between the parameters, ΔpH,
△ PO₂, △ PCO₂, △ BE, △ HCO₃ ^-To calculate.
Here, ΔpH = pHat−pHve, and the same applies to other cases.
is there. Furthermore, as a ratio of each parameter, pHat /
pHve, PO₂at / PO₂ve, PCO₂at / PCO₂ve, B
Eat / BEve, HCO₃ ^-at / HCO₃ ^-Calculate ve. So
In addition, the rate of change in each parameter (PO₂at
-PO₂ve) / PO₂Etc. are calculated.

When the control section 40 calculates the information as shown above, for example, it becomes possible to determine the lesion of metabolic acid-base imbalance and determine its degree. In addition, the oxygen uptake of the target organ can be grasped.

The oxygen content CaO ₂ is generally represented by the following formula.

CaO ₂ = (Hb × 1.34 × SaO ₂ ) +
(0.003 × PO ₂ ). That is, the oxygen content includes oxygen bound to hemoglobin (Hb × 1.34 × SaO ₂ ) and dissolved oxygen in plasma (0.003 × PO ₂ ). The total amount of oxygen bound to hemoglobin is the hemoglobin content (Hb) and the oxygen binding capacity of hemoglobin (1.34 mlO ₂ / gH
It is obtained as the product of b) and the oxygen saturation of hemoglobin (SaO ₂ ). This equation can be used to calculate the oxygen content of any blood or plasma sample.

Since the oxygen uptake is the difference ΔCaO ₂ between the oxygen content of the arterial side and the blood side of the vein that sandwich the target organ, if Hb and SaO ₂ are known, PO ₂ measurement is performed in this embodiment. By performing the operation and vein simultaneously, the control unit 40 can calculate the oxygen intake amount. Incidentally, SaO
₂ (SpO ₂ ) can be measured quickly and easily by the recent spread of pulse oximetry.

One of the clinical meanings of conventional PCO ₂ values is:
It is to be used as a value for distinguishing hypercapnia and hypocapnia. That is, PCO ₂ is 45 mmH
It is diagnosed that hypercapnia is higher than g and hypocapnia is lower than 35 mmHg. Hypercapnia generally exhibits hypoventilation. The relationship is clear from PCO ₂ = VCO ₂ × 0.863 / VA (VCO ₂ : carbon dioxide production) (VA: alveolar ventilation). Therefore, PCO ₂ in arterial blood
Is the key clinical data for assessing lung disease.

According to the blood gas measuring apparatus of this embodiment, in addition to the above evaluation, the amount of carbon dioxide gas produced by each organ Δ
PCO ₂ can be evaluated directly. The ΔPCO _{2 for each} organ is also important clinical data for grasping the state of the organ. The value of ΔPCO ₂ is not affected even if a lung disease is also present, and therefore ΔPCO ₂ at the organ level can be known.

As described above, an example of the information newly obtained by this embodiment has been shown. By providing this embodiment,
Of course, more useful information can be obtained.

FIG. 7 shows a display example on the display unit 50 of this embodiment. In FIG. 7A, a display example when the liver is targeted is shown. At 81, a mark indicating that the current target is the liver is displayed. This may be set, for example, by an operation unit (not shown) provided in the display unit 50. 82 includes, for example, pHat / p
A graph showing the time change of Hve and similarly (PO ₂ at-
The graph showing the time change of PO ₂ ve) / PO ₂ and PCO ₂ at / PCO ₂ ve is displayed in real time. Also,
At 83, the rate of change of each information is shown in percentage with a sign.

FIG. 7 (a) is merely an example of the display on the display unit 50. For example, the oxygen intake amount ΔC described above is used.
aO ₂ may be displayed. The display content on the display unit 50 can be changed according to the clinical situation, and for example, the display content can be set by an operation unit (not shown).

FIG. 7A shows a display example when the target is the liver. However, when the target is another organ, the display is the same as in FIG. 7A. FIG. 7B
FIG. 7 shows a list of marks identifying the organ displayed at 81 in FIG.

As described above, according to this embodiment, by providing the arterial probe and the venous probe in the blood gas measuring apparatus, the operator can directly determine the target organ state in real time. It becomes possible to grasp.

The present embodiment is characterized in that a local condition is grasped by placing a probe in an artery and a vein with a target organ sandwiched therebetween. However, for example, only one of the probes may be used. The same function as that of the conventional blood gas measuring device can be achieved.

Although one example of the present invention has been described above, those skilled in the art will be able to make various changes without departing from the spirit and scope of the present invention. Therefore, the invention is not intended to be limited except by the following claims.

Further, the present invention may be realized, for example, by giving a program to the device, or may be realized as a system composed of a plurality of devices.

[0058]

As described above, according to the present invention, by providing the arterial probe and the venous probe in the blood gas measuring apparatus, the operator can obtain the direct blood gas information in the local field of the living body. It can be obtained continuously, and the state of the target organ can be easily grasped. Furthermore, since the second sensor probe has a catheter shape, the probe can be reliably inserted up to the vicinity of the target organ, and accurate information can be obtained. Furthermore, since the calculation can be performed only with the signal from the first or second probe, it is possible to use the first and second probes alone. Furthermore, since the first probe can be inserted into a vein and the second probe can be inserted into an artery as well, the applicable range of the first probe and the second probe can be expanded and can be used properly depending on the case. Furthermore, the first
It is possible to reliably measure the analyte by obtaining and calculating blood gas information by the sensitive means whose emission intensity or quenching speed changes depending on the concentration of the analyte by the probe and the second probe. .

[0059]

[Brief description of drawings]

FIG. 1 is an external view of a blood gas measuring device according to an embodiment of the present invention.

FIG. 2 is a diagram showing an indwelling needle type artery probe in the present embodiment.

FIG. 3 is a diagram showing a catheter-type vein probe in the present embodiment.

FIG. 4 is a diagram showing a state in which air is injected into the balloon of the catheter in the present embodiment.

FIG. 5 is a diagram showing a catheter lumen in the present embodiment.

FIG. 6 is a diagram showing a sensor configuration in the probe of the present embodiment.

FIG. 7 is a diagram showing a display example on the display unit of the present embodiment.

[Explanation of symbols]

10 Arterial probe 20 Vein probe 40 Control unit 50 Display unit 31, 32 Connector 11 pH probe 12 PO ₂ probe 13 PCO ₂ probe 14 Outer layer film 15 Reflector 16 Oxygen sensitive phosphor 17 pH sensitive phosphor

Claims (9)

[Claims] 1. A device for measuring an analyte in blood in a living body, comprising: a first sensor probe placed in an artery; a second sensor probe placed in a vein; and the first sensor. A blood analyte measuring device, comprising: a probe, a calculation unit that calculates a signal detected by the second sensor probe, and a display unit that displays a calculation result of the calculation unit. 2. The display means displays the calculation result of the calculation means as information on an organ existing between the first sensor probe and the second sensor probe. The blood analyte measuring device described. 3. The blood analyte measuring device according to claim 1, wherein the second sensor probe has a catheter shape that can be inserted into a desired position in the body. 4. The blood analyte measuring device according to claim 1, wherein the computing means is capable of computing only with a signal detected by the first sensor probe. 5. The blood analyte measuring device according to claim 1, wherein the computing means is capable of computing only with a signal detected by the second sensor probe. 6. The blood analyte measuring device according to claim 1, wherein the first sensor probe can be placed in a vein. 7. The blood analyte measuring device according to claim 1, wherein the second sensor probe can be placed in an artery. 8. The first and second sensor probes transmit the light emission intensity or the extinction speed as optical information, and a responsive unit that changes the light emission intensity or the extinction speed according to the concentration of the analyte. The blood analyte measuring device according to claim 1, further comprising: 9. The analyte is pH, PO ₂ , PC
The blood analyte measuring device according to claim 1, which is O ₂ .