JPH03176029A - Catheter for measuring cardiac output - Google Patents

Abstract

PURPOSE:To make it possible to feed a fluid without exerting an undesirable influence on the measurement of a cardiac output by dividing the 1st and the 3rd lumens with the 1st partition, dividing the 2nd and 3rd lumens with the 2nd partition and positioning a temp. sensitive element on rather a base end side than an opening part. CONSTITUTION:The inner cavity of a catheter main body 21 is divided into four parts with three partitions 21, 22 and 23 and a thermister lumen 24 is formed with the inner wall 20 of the inner cavity and the 1st partition 21. Thermisters 41 and 45 are positioned water-tightly in side holes 281 and 285 and a regurgitation hole 7 is positioned on rather a base end side than the thermisters 41 and 45. On the other hand, the 2nd partition 22 is formed on the facing position in the inner cavity and a lumen 26 for measurement of pressure is formed with it and the inner wall 20 of the inner cavity. In addition, the 3rd partition 23 is provided in a space constituted of the inner wall 20 and the partitions 21 and 22 to form a balloon lumen 27, and a lumen 25 for feeding an indicator liq. is formed between the partitions 21 and 22.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a catheter for measuring cardiac output that is connected to a cardiac output measuring device used when performing a cardiac function test.

<Prior Art> A thermodilution method is used to measure cardiac output by right heart catheterization for cardiac function testing.

In right heart catheterization, a catheter is introduced from the jugular vein, femoral vein, cubital vein, etc., and is inserted into the superior vena cava, inferior vena cava,
It is placed through the right atrium and right ventricle so that its tip is located in the pulmonary artery.

The catheter has an ejection port located in the right atrium and a thermistor as a temperature sensing element located in the pulmonary artery.

In this case, the discharge port is provided on the proximal end side of the thermistor, and a liquid having a temperature higher or lower than the blood temperature is injected from the discharge port.

At this time, the temperature of the liquid is diffused and diluted in the right atrium and right ventricle.

This diluted temperature is detected by a thermistor located in the pulmonary artery, and cardiac output is calculated from the dilution curve, that is, the change in detected temperature over time, using the Stewart-Hamilton method.

However, cardiac output measurement using this thermodilution method can only be performed intermittently and cannot be used for continuous measurement of cardiac output. Furthermore, if multiple measurements are attempted, the total amount of liquid to be injected increases, which increases the burden on the subject and increases the risk of infection due to the operation.

Therefore, Japanese Patent Application Laid-Open No. 62-207435 (US Pat. No. 4,841,981) proposes a catheter for measuring cardiac output that can continuously measure cardiac output.

This device is equipped with a temperature-sensitive element that can be applied to thermodilution cardiac output measurement and blood flow velocity measurement, continuously measuring blood flow velocity, and calculating cardiac output from this continuously. That is what it is.

Representative examples of such catheters are shown in Figures 9 and 10.
As shown in the figure.

The catheter 1 shown in FIGS. 9 and 10 has four lumens within the catheter body 2. The catheter 1 shown in FIGS.

More specifically, the tip of the catheter body 2 has a pressure port 6.
and a balloon 8 made of a flexible elastic body attached so as to cover the entire catheter tube from the tip to several mm behind.

The catheter body 2 also includes a balloon side hole 7 provided on the side surface of the inner balloon tube in order to expand and contract the balloon 8, and a second thermistor 45 provided at a position of 10 to 20 m from the tip. 1 more from there
First thermistor 4 placed on the proximal end side by 0 to 15 mm
1, and a discharge port 5 provided at a position closer to the base end than the thermistor 41, 45 and 12 to 40 cm from the tip.

This item is inserted through a vein in the upper or lower limb,
Since the catheter is used by being placed in the pulmonary artery, the thermistors 41 and 45 are provided on the distal end side of the catheter, which is downstream of the blood flow from the discharge port 5. Unlike this, it is possible to use it by placing it in the pulmonary vein, but in that case, thermistors 41 and 45 are placed on the proximal end side of the catheter, which is downstream of the blood flow from the discharge port 5. Become.

The pressure port 6, the balloon side hole 7, the thermistor 41, 45, and the discharge port 5 each communicate with four independent lumens. That is, the pressure port 6 communicates with a lumen 36 for measuring pressure such as pulmonary artery pressure, and the balloon side. The hole 7 communicates with the balloon lumen 37, the thermistor 41.45 communicates with the thermistor lumen 34, and the discharge port 5 communicates with the injection lumen 35 after injection instruction f.

Furthermore, at the rear end 29 of the catheter body 2, the thermistor lumens 34 are connected to connectors 941 and 945 via tubes, and the lead wires connected to the respective thermistors 41 and 45 are connected from the thermistor lumens 34 to Connector 941 through the tube
．． It is electrically connected to 945.

Further, in the rear end portion 29 of the catheter body 2, the pressure measurement lumen 36, the indicator liquid injection lumen 35, and the balloon lumen 37 are connected to connectors 96, 95, and 97 via tubes, respectively.

Note that the first thermistor 41 as a temperature sensing element is for thermodilution cardiac output measurement, and the second thermistor 45 is for thermodilution cardiac output measurement.
is a heat-generating thermistor such as a self-heating type or indirect heating type, which is heated by electricity or a heater and outputs its own temperature as a heating temperature signal to detect blood flow speed.

In such a case, the four lumens 34 in the above publication
．． 35, 36, and 37 are formed by dividing the inner lumen of the catheter body 2 into four parts from the center in a fan shape with a partition wall 28, as shown in FIG.
6 and the thermistor lumen 34 are arranged next to each other.

<Problems to be Solved by the Invention> When such catheters for measuring cardiac output are used clinically, since they are for continuous measurement, there is a possibility that continuous measurement may occur during the measurement, especially when measuring over a long period of time. In some cases, it may be necessary to infuse a fluid, and it becomes necessary to continuously flow a fluid such as an infusion through the opening of the pressure port 6 at the tip of the catheter for pressure measurement.

In such a case, the thermistor lumen 34 is adjacent to the pressure measuring lumen 36, as shown in FIG. 10, and when a liquid passes next to the thermistor 41.45, the thermistor 41.45 It is affected by temperature.

More specifically, the second thermistor 45, which is a heat-generating thermistor, is normally heated by constant current and detects its own temperature. Then, the blood flow velocity is determined from the temperature detected by the first thermistor 41, the temperature detected by the second thermistor 45, the heating current, etc.

At this time, if the temperature inside the thermistor lumen is greatly affected by the temperature of the fluid flowing inside the pressure measurement lumen 36, the heating temperature signal, blood temperature signal, current value during energization, etc. will fluctuate, making it impossible to accurately detect blood flow velocity. The problem is that it disappears.

Such an effect may also occur when only the first thermistor 41 for measuring cardiac output is used.

Furthermore, in the above-mentioned Japanese Patent Laid-Open No. 63-207495, the thermistor lumen 34 and the pressure measurement lumen 36 are arranged adjacent to each other. In the partition wall structure as described in the above publication, as shown in FIG. 10, even if the lumen 37 is used as a pressure measurement lumen or the thermistor lumen 34 and the pressure measurement lumen are separated, both partition walls are in contact with each other. In particular, it has been found that there is a risk that accurate blood flow velocity measurement may not be possible.

In particular, an object of the present invention is to measure cardiac output and blood flow velocity while also injecting a liquid such as an infusion agent into a blood vessel from the tip opening of a catheter. An object of the present invention is to provide a power supply for measuring cardiac output that can be injected with liquid without adversely affecting the measurement of cardiac output.

Means for Solving the Problems> These objects are achieved by the following inventions (1) to (9).

(1) The lumen of the catheter body is divided by a partition wall into a first lumen that accommodates the temperature sensing element and its lead wire, a second lumen that communicates with the opening, and one or more third lumens. A catheter for measuring cardiac output having a lumen, wherein a first partition among the partitions partitions the first lumen and the third lumen, and a second partition that is not connected to the first partition. partitioning the second lumen and the third lumen.

A catheter for measuring cardiac output, characterized in that the temperature sensing element is disposed closer to the proximal end than the opening.

(2) The cardiac output measuring catheter according to (1) above, further comprising one or more third partition walls to form two or more third lumens.

(3) The third partition wall connects the inner walls of the lumen (
2) The catheter for measuring cardiac output according to item 2).

(4) The catheter for measuring cardiac output according to (2) above, wherein the third partition connects the inner wall of the lumen with the first partition and/or the second partition.

(5) The cardiac output measuring catheter according to (2) above, wherein the third partition wall connects the first partition wall and the second partition wall.

(6) The above (2) wherein the temperature sensing element is a thermistor for measuring thermodilution cardiac output and a heat-generating thermistor for measuring blood flow velocity.
The catheter for measuring cardiac output according to any one of 1) to (5).

(7) The above (1)--wherein the opening is a pressure detection opening, and the second lumen is a pressure measurement lumen.
The catheter for measuring cardiac output according to any one of (6).

(8) the third lumen has an indicator liquid injection lumen communicating with a liquid discharge port for thermodilution cardiac output measurement;
The cardiac output measuring catheter according to (7) above, wherein the discharge port is disposed closer to the proximal end than the temperature sensing element.

(9) Cardiac output measurement according to any one of (1) to (8) above, further comprising a balloon at the distal end of the catheter body, and a balloon lumen communicating with the balloon as the third lumen. catheter.

<Specific configuration> Hereinafter, the specific configuration of the present invention will be explained in detail.

The external structure of a representative example of the cardiac output measuring catheter 1 of the present invention is the same as that shown in FIG. , JP-A-62-2.

In some cases, the catheter for measuring cardiac output of the present invention may include a first tube for measuring cardiac output in the thermistor lumen.
It is also possible to have only the thermistor 41.

As described above, the catheter for measuring cardiac output of the present invention has a thermistor as a temperature sensing element.

The catheter for measuring cardiac output of the present invention has three or more lumens within the lumen of the catheter body.

It has one or more thermistor lumens, which constitute a first lumen.

There is usually one thermistor lumen, but for example, the first
Alternatively, the second thermistor 41, 45 and its lead may be housed in separate lumens.

Further, the first lumen has an opening disposed closer to the tip side than at least one of the thermistors of the first lumen.
+-Ha 1. Examples of the second lumen include a pressure measurement lumen having a pressure port 6 for measuring pressure such as pulmonary artery pressure. Such a case is the case with a catheter whose tip is placed in the pulmonary artery.

In addition, a lumen having an opening for infusion may be provided separately.

In addition, in the case of a catheter whose tip is placed in the pulmonary vein,
Since the discharge port of the indicator liquid injection lumen is disposed closer to the tip than the thermistor, in addition to the pressure measurement lumen, this indicator liquid injection lumen is also a second lumen.

Additionally, the catheter lumen is provided with one or more third lumens.

The third lumen is connected to the first and second thermistors 41 .
A typical example of this is a lumen for injecting an indicator liquid in the case of a catheter whose tip is indwelled in the pulmonary artery. In this case, since the discharge port 5 is disposed on the proximal side of the thermistor 41.45, the indicator liquid injection lumen on the distal side of the discharge port 5 is normally connected to the resin injection port on the proximal side of the thermistor 41.45. It is blocked by etc.

Therefore, at this time, the indicator liquid does not flow up to the thermistor part 4i45, and the indicator liquid does not affect the temperature of the thermistor, and the temperature of the indicator liquid is not affected by the self-heating type thermistor described later. do not have.

In such a case, if the structure is such that the liquid flows to the thermistor at the tip of the indicator liquid injection lumen without blocking the tip side of the lumen with a resin or the like, the lumen is referred to as the second lumen.

In addition, in the catheter for measuring cardiac output of the present invention, although the balloon is not necessarily required, the fluid flowed into the balloon, for example, gas such as CO2, has an insulating effect.
A balloon lumen is preferred in the present invention as it reduces thermal effects.

In addition, as the third lumen, a lumen for injecting a drug solution or the like may be provided.

Three or more, usually four to five, lumens are formed by dividing the lumen of the catheter body into sections using partition walls.

In the present invention, as shown in FIG. 1 and FIG. Lumen 2 for pressure measurement as the lumen of
The second partition walls 22 that partition the partitions 6 and 6 are configured so as not to be connected to each other.

More specifically, in the example shown in FIGS. 1 and 2, the lumen of the catheter body extends in the longitudinal direction of the catheter body, and the hooks extend along the lumen inner wall 20 and are arranged substantially parallel to each other. 3
It is divided into four parts by four flat partition walls 21, 22, and 23.

Then, the lumen inner wall 20 of the catheter body and the first partition wall 2
1 and the thermistor lumen 2 from the inner lumen outer periphery.
4 is formed as the first lumen.

This thermistor lumen 24 has a side hole 2 that penetrates outward.
81.285, and a thermistor 4 is placed in this side hole in a liquid-tight manner.
1.45 is arranged, and inside the thermistor lumen 24,
Respective leads 43 and 47 are housed.

Note that these thermistors 41 and 45 are the first thermistor 41 for measuring thermodilution cardiac output and the second thermistor 45 of a heat-generating type, more preferably a self-heating type, for measuring blood flow velocity. be. These thermistors 41.
For details on the configuration and operation of 45, see Japanese Patent Application Laid-Open No.
Please refer to the publication No.-207435.

On the other hand, a second partition wall 22 is formed in the lumen of the catheter body 2 at a position facing the thermistor lumen 24 and is substantially parallel to the first partition wall 21. The inner wall 20 forms a pressure measurement lumen 26 as a second lumen.

This pressure measurement lumen 26 has a thermistor 41.45
It communicates with a pressure port 6 as an opening that opens at the tip end. The pressure is measured through the pressure measurement lumen 26, and it is also possible to continuously administer an infusion agent or the like through the pressure measurement lumen.

Furthermore, a third partition wall 23 is provided in a space formed by the inner wall 20 of the lumen of the catheter body 2 and the first and second partition walls 21.22, and the partition wall 22.
．． There is a balloon lumen 27 between 23 and the partition wall 21.2.
An indicator liquid injection lumen 25 is formed between the two.

The balloon lumen 27 communicates with the side hole 7 and allows the balloon 8 to be deflated and expanded.

Further, the indicator liquid injection lumen 25 communicates with the discharge port 5 shown in FIG.

Although not shown, the indicator liquid injection lumen 25 on the distal end side of the discharge port 5 is usually closed with a resin such as PVC, and the discharged liquid for measuring cardiac output is passed through the thermistor 41.
．． The liquid is prevented from flowing into the vicinity of 45.

In this way, the first and second partition walls 21 respectively partition the thermistor lumen 24 as the first lumen and the pressure measurement lumen 26 as the second lumen.
22 are not in contact with each other, the measured value of blood flow velocity is not disturbed by the thermal influence of the fluid applied to the thermistor 41, 45, especially the infusion fluid injected into the pressure measurement lumen.

In the illustrated example, the balloon lumen 27 formed between the thermistor lumen 24 and the pressure measurement lumen 26 stores gas for deflation and expansion, and the tip of the indicator liquid injection lumen 25 prevents the inflow of liquid. Since the tip is insulated with resin or the like and filled with air or the like, the effect of the present invention is further enhanced by these heat insulating effects.

In this case, it is better for the thermistor 41, 45 and the discharge port 5 to be located relatively close to each other on the outer periphery of the thermistor body 2, so it is preferable that the indicator liquid injection lumen 25 and the thermistor lumen 24 be adjacent to each other.

In addition, in the case of a catheter in which liquid is allowed to flow into the tip of the indicator liquid injection lumen 25 or whose tip is indwelled in the pulmonary vein, the positions of the balloon lumen 27 and the indicator liquid injection lumen 25 may be different from the illustrated example. Conversely, if the partition wall 23 is made to function as a second partition wall, these partition walls 21, 23
Since they are not in contact with each other, the effects of the present invention can be effectively realized even in this case.

Furthermore, the lumen diameter of the catheter body 2 is 0.8 to 2.5 m.
It is about m. For this reason, such a first partition wall and a second partition wall should normally be separated by about 0.4 to 1.5 mm.

Further embodiments are shown in FIGS. 3 and 4, respectively.

The example shown in FIG. 3 is an example in which the balloon 7 and balloon lumen 27 are omitted from the examples shown in FIGS. 1 and 2. That is, the first
The partition wall 21 and the second partition wall 22 that is not in contact with the partition wall 21 and the second partition wall 22 that are not in contact with this are connected to form a structure with three lumens, including an indicator liquid injection lumen 25 that blocks the flow of liquid to the tip, a thermistor lumen 24, and a pressure measurement lumen. This is an example where it is placed between the lumens 26.

In the example shown in FIG. 4, a partition wall 211 is provided, and a partition wall 215 is hung between the lumen inner wall 20 and the partition wall 211, similar to the first partition wall 21 in the example shown in FIGS. is passing.

As a result, the thermistor lumen is divided into two parts, each including a part of the partition wall 211, a part of the lumen inner wall 20, and a part of the partition wall 21.
5 and a thermistor lumen 241.2 that accommodates a first and second thermistor 41.45, respectively.
45 are provided.

In the case of this example shown in FIG.
The partition wall 211.215 that divides the thermistor lumen 241.245 functions as the first partition wall 21,
Both of these partition walls 211 and 215 are connected to the second partition wall 22.
Not connected with.

Next, FIG. 5 shows yet another example.

In the example shown in FIG. 5, partition walls 29 and 22 are provided on the inner wall 20 of the lumen, substantially parallel to each other, and a partition wall 212 is provided between the inner wall 20 of the lumen and the partition wall 28.

The thermistor lumen 2 is formed by the partition wall 211, the partition wall 212, and the lumen inner wall 20, which constitute a part of the partition wall 29.
Partition wall 27 which fractionates 4 and also constitutes a part of partition wall 29
The balloon lumen 27 is divided by the partition wall 212 and the lumen inner wall 20, and the indicator liquid injection lumen 25 is further partitioned by the partition wall 29.22 and the lumen inner wall.
9, and a pressure measurement lumen 26 is divided by the inner wall of the lumen.

In this case as well, the partition walls 211 and 212 that divide the thermistor lumen 24, which is the first lumen in the present invention, constitute the first partition wall 21, and this partition wall 21 separates the pressure measurement lumen 26, which is the second lumen. It is not connected to the second partition wall 22 that separates the.

However, an indicator liquid injection lumen 25 and a balloon lumen 27 are formed as a third lumen between the thermistor lumen 24 and the pressure measurement lumen 26, which are the first and second lumens, respectively. The third lumen is divided by a third partition 23.

In this case, the third partition wall 23 is connected to the partition wall 211 that forms part of the first partition wall, and the partition wall 29 extends linearly.
However, from the opposite perspective, the third partition wall 23
is arranged so as to connect the lumen inner wall 20 and the first partition wall 21.

In this way, the first and second partition walls 2 are attached to the inner wall 20 of the lumen.
1.23 are arranged so as not to connect or intersect with each other, and as shown in FIGS. As shown in the figure, a plurality of third lumens can be formed by providing a third partition wall 23 that connects the first partition wall 21 and the lumen inner wall 20, and any of the third lumens can be formed according to the present invention. The effect is expressed.

At this time, the balloon lumen 27 as the third lumen and the indicator liquid injection lumen 25 exhibit a heat insulating effect.

In such a case, the third partition wall 23 may connect the lumen inner wall 20 and the second partition wall 22.

Further, the third partition wall 23 may connect the first partition wall 21 and the second partition wall 22.

Further, a plurality of third partition walls 23 may exist.

That is, in the present invention, rjs t of the catheter body 2
Fk rjs +, = Y Ri 1. s t:”
亦h A fp 1. s whistle 1 se17 G whistle bulkhead 21.
22 and a portion of the lumen inner wall 20 define first and second lumens, respectively, and the lumen inner wall 20
, an arbitrary position of the first partition wall 21 and the second partition wall 23 is connected by one or more third partition walls, and the first and second partition walls
Two or more third lumens may be formed between the partition walls.

In the example shown in FIG. 6 for a catheter placed in the pulmonary artery, the first
The second partition walls 21 and 22 form a thermistor lumen 24 as a first lumen and a pressure measurement lumen 26 as a second lumen.

A partition wall 23 is connected between the partition walls 21 and 22, and the inner wall of the lumen, a portion of the first and second partition walls 21 and 22, and the partition wall 23 form a balloon lumen as a third lumen. In the example shown in FIG. 7, the first A partition wall 21 is formed to form a concentric arc fan-shaped thermistor lumen 24 as a first lumen, and a partition wall 221, 222, 22 is formed.
3, a second partition wall 22 is formed, and a fan-shaped pressure measurement lumen 26, which is spaced apart from the first lumen and also has a concentric arc shape, is formed as a second lumen.

These first partition walls 21 (partition walls 211, 212
．． 213) and the second partition 22 (partition 221.222.2
23) are connected by arc-shaped partition walls 231, 235 to form third lumens 25, 27, 28.

In this case, concentric fan-shaped lumens located on the outer circumferential side of the inner cavity are the balloon lumen 27 and the indicator liquid injection lumen 25, and these and the circular lumen 28 at the center are filled with air or gas. , which has an insulating effect.

In this case, the central lumen 28 is usually filled with air, but it can also be used as a lumen for placing a guide wire in the lumen and improving the pushability when inserting the catheter into the body. You can also do that.

In addition, in the case of FIG. 7 as well, the third partition walls 231 and 235 are
The first partition wall 21 and the second partition wall 22 are connected.

Furthermore, another example is shown in FIG.

The example shown in FIG. 8 is different from the example shown in FIG.
The connection point of the second partition wall 22 with the lumen inner wall 20 is brought closer to the connection point of the third partition wall 23 with the lumen inner wall 20.

Is this an indication? When opening the discharge port 5 in the J2 injection lumen 25, a wider opening can be obtained without reducing the cross-sectional area of the pressure measurement lumen 26.

Therefore, the injection resistance of the indicator liquid is reduced, and furthermore, the processing of the opening becomes easy.

Also in this case, the effects of the present invention are exhibited because the first partition 21 formed by the partitions 211 and 215 does not contact the second partition.

Note that as the material of the catheter body 2, resins such as polyurethane, polyvinyl chloride, ethylene vinyl acetate copolymer, polyethylene, and polypropylene are used.

Further, as the material of the balloon 8, latex rubber, silicone rubber, etc. are used.

The wall thickness of the catheter body 2 is approximately 0.1 to 0.5 mm, and the wall thickness of the partition walls 21, 22, 23, etc. is 0.05 to 0.0 mm.
．． It should be about 5mm.

Further, it is preferable that the outer surface of the portion of the catheter body 2 to be placed in the blood vessel is coated with an antithrombotic material.

This makes it possible to prevent the occurrence of blood clots when cardiac output is measured continuously for a long period of time.

As such an antithrombotic material, a copolymer of a hydroxyethyl methacrylate polymer and a styrene polymer is preferably used.

In addition, the structure and operation of the catheter for measuring cardiac output of the present invention are detailed in the aforementioned Japanese Patent Application Laid-Open No. 62-207435.

Functional Effect> The catheter for measuring cardiac output of the present invention can simultaneously measure cardiac output while infusing fluid from the pressure port for measuring pressure.

[Brief explanation of drawings]

FIG. 1 is a longitudinal sectional view of the distal end portion of an example of the catheter for measuring cardiac output of the present invention. FIG. 2 is an enlarged cross-sectional view taken along the line ■--■ in FIG. FIGS. 3 to 8 are enlarged cross-sectional views of the distal end portion of another example of the catheter for measuring cardiac output of the present invention. FIG. 9 is a front view showing the external configuration of a conventional catheter for measuring cardiac output. FIG. 10 is an enlarged cross-sectional view taken along line ■--■ in FIG. Explanation of symbols 1...Catheter for measuring cardiac output 2...Catheter body 20...Lumen inner wall 21...First partition wall 22...Second partition wall 23...Third partition wall Partition wall 24...Thermistor lumen 25...Indicator liquid injection lumen 26...Pressure measurement lumen 27...Balloon lumen 41.45...Thermistor 43.47...Lead wire 5...Discharge Outlet 6...Pressure port 7...Balloon side hole 8...Balloon FIG, 8 FIG, 10

Claims (9)

[Claims] (1) The lumen of the catheter body is divided by a partition wall into a first lumen that accommodates the temperature sensing element and its lead wire, a second lumen that communicates with the opening, and one or more third lumens. A cardiac output measuring catheter having a lumen, the first lumen and the third lumen being partitioned by a first partition among the partitions, and a second partition not connected to the first partition. According to the second
A catheter for measuring cardiac output, characterized in that the lumen and the third lumen are partitioned, and the temperature sensing element is disposed closer to the proximal end than the opening. (2) The catheter for measuring cardiac output according to claim 1, further comprising one or more third partition walls to form two or more third lumens. (3) The cardiac output measuring catheter according to claim 2, wherein the third partition wall connects the inner walls of the lumen. (4) The catheter for measuring cardiac output according to claim 2, wherein the third partition wall connects the inner wall of the lumen and the first partition wall and/or the second partition wall. (5) The cardiac output measuring catheter according to claim 2, wherein the third partition wall connects the first partition wall and the second partition wall. (6) The catheter for measuring cardiac output according to any one of claims 1 to 5, wherein the temperature sensing element is a thermistor for measuring thermodilution cardiac output and a heat-generating thermistor for measuring blood flow velocity. . (7) Claims 1 to 6, wherein the opening is a pressure detection opening, and the second lumen is a pressure measurement lumen.
The catheter for measuring cardiac output according to any one of the above. (8) the third lumen has an indicator liquid injection lumen that communicates with a liquid discharge port for thermodilution cardiac output measurement;
The catheter for measuring cardiac output according to claim 7, wherein the discharge port is disposed closer to the proximal end than the temperature sensing element. (9) The cardiac output measuring catheter according to any one of claims 1 to 8, further comprising a balloon at the distal end of the catheter body, and a third lumen communicating with the balloon.