Patent Description:
As is well known, in cardiac surgery or the like, cardiopulmonary bypass (CPB) is performed to suspend the heart or bring it an approximately suspended state as necessary using an extracorporeal blood circulation apparatus.

In such cardiopulmonary bypass (CPB), gas exchange of blood is performed by a membrane lung (hereinafter, may be referred to as "ML").

In the cardiopulmonary bypass (CPB), for example, a monitoring apparatus used to grasp whether or not the gas exchange of blood by the membrane lung (ML) is appropriately performed has been developed (for example, refer to Patent Document <NUM>).

On the other hand, when treating an acute pneumonia patient (ARDS), functional deterioration of a native lung (hereinafter, may be referred to as "NL") may be restored using a ventilator.

When using the ventilator, lung ventilation by the ventilator does not only sufficiently function due to the functional deterioration of the native lung (NL), but the native lung function may also decrease by using the operation of the ventilator.

Accordingly, in the treatment for the acute pneumonia patient (ARDS), the native lung function may be partially suspended, and the gas exchange of blood may be performed by assisted circulation (ExtraCorporeal Membrane Oxygenation, hereinafter referred to as "ECMO") in order to compensate for the functional deterioration of the native lung (NL).

Specifically, the membrane lung (ML) and the native lung (NL) are used together, and by performing gas exchange in the membrane lung (ML) on blood removed from the patient and returning the blood into the human body again, the function of the native lung (NL) is assisted by the membrane lung (ML).

The treatment by such assisted circulation (ECMO) may be performed for a long period of time, for example, from several days to a month, and the burden on health care workers tends to increase.

<CIT> relates to a ventilation system comprising a device for mechanical ventilation, in particular positive-pressure ventilation, of the lungs of a patient, and an ECLS device for extracorporeal blood gas exchange.

<CIT> relates to a device for the continuous monitoring of blood characteristic quantities in an external cardiovascular supporting circuit.

<CIT> relates to a control unit for controlling the operation of either or both of a first and second apparatus of which one is a ventilator for providing a respiratory treatment to a subject by supplying a breathing gas to the lungs of the subject, and the other is a lung assist device for providing an extracorporeal lung assist [ECLA] treatment to the subject by generating a flow of blood from the subject, oxygenating the blood, and returning the oxygen-enriched blood to the subject. The control unit is configured to generate a control signal controlling the operation of the second apparatus in response to a control parameter obtained by the first apparatus.

<CIT> relates to a medical device for providing extracorporeal lung assist (ECLA) treatment to a patient through extracorporeal removal of CO2 from the patient's blood, and to a system including such a medical device. The invention also relates to a method for extracorporeal removal of CO2 from the patient's blood.

However, when the gas exchange of blood is performed by the assisted circulation (ECMO), since the gas exchange of blood is not only performed in the membrane lung (ML) but is also performed in the native lung (NL), it is not easy to grasp whether or not the gas exchange of blood is appropriately performed by the assisted circulation (ECMO).

The management of the native lung (NL) by the ventilator relies on the monitoring for the ventilation amount, the end expiratory carbon dioxide partial pressure and the like, and it is difficult to control every respiration of the patient (living body) having the gas exchange of blood performed by using the assisted circulation (ECMO).

Therefore, in the treatment using the assisted circulation (ECMO), by intermittently blood gas-analyzing the blood collected from the patient and controlling whether or not the gas exchange of blood in the living body is appropriate, it is necessary to grasp whether or not the gas exchange of blood by the assisted circulation (ECMO) and every respiration of the patient by the native lung (NL) and the membrane lung (ML) are appropriately performed. Accordingly, it is a heavy burden on health care workers.

The present invention is made in consideration of the above circumstances, and an object thereof is to provide a monitoring apparatus capable of accurately grasping the gas-exchanging state of blood in a patient connected with an assisted circulation apparatus, and the assisted circulation apparatus including it.

In order to solve the above problems, the present invention is proposed.

In the present description, the blood gas-exchanging state index includes, for example, an index indicating a blood-oxygenated state (hereinafter, may be referred to as blood-oxygenated state index) and an index indicating a gas-exchanging amount (hereinafter, may be referred to as gas exchange index) at the time of oxygenating blood.

As the blood-oxygenated state index, well-known parameters such as the oxygen saturation degree in the membrane lung, the oxygen saturation degree in the living body, further, the hemoglobin concentration of blood, and the oxygen partial pressure of blood may be applied.

As the gas exchange index, well-known parameters such as the oxygen uptake amount in the membrane lung or the native lung, further, the carbon dioxide emission amount in the membrane lung or the native lung, the oxygen concentration (oxygen content, oxygen partial pressure) of gas capable of calculating them, the carbon dioxide concentration (carbon dioxide content, carbon dioxide partial pressure) thereof, and the gas supply amount thereof may be applied. Instead of the oxygen concentration, the carbon dioxide concentration and the like, a partial pressure of known respiratory gas (for example, anesthesia gas or the like) and the gas supply amount thereof, and the like may be applied.

When obtaining the gas exchange index (for example, the oxygen uptake amount) for oxygenating blood in the native lung, for example, respiratory gas using a ventilator, further, for example, the oxygen concentration of respiratory gas in natural breathing (for example, a case of using an oxygen mask) may be applied.

For example, the carbon dioxide (CO<NUM>) concentration and the oxygen (O<NUM>) concentration may be referred to as an oxygen content rate parameter as a parameter related to the gas content for oxygenating blood.

In an embodiment of the invention, a calculation unit (<NUM>) may calculate the blood gas-exchanging state index based on a gas-exchanging amount of blood in the membrane lung.

The calculation unit calculates the blood gas-exchanging state index indicating the gas-exchanging state of blood by the assisted circulation apparatus based on the gas-exchanging amount of blood in the membrane lung, so the gas-exchanging state of blood by the membrane lung can be accurately grasped.

In an embodiment of the invention, the calculation unit may calculate the gas-exchanging amount of blood in the membrane lung based on at least one of a carbon dioxide emission amount in the membrane lung and an oxygen uptake amount in the membrane lung.

The calculation unit calculates the gas-exchanging amount of blood in the membrane lung based on at least one of the carbon dioxide emission amount in the membrane lung and the oxygen uptake amount in the membrane lung, so the gas-exchanging amount of blood in the membrane lung can be efficiently and accurately calculated.

As a result, the gas-exchanging state of blood by the membrane lung can be accurately grasped.

The phrase "at least one of the carbon dioxide emission amount and the oxygen uptake amount in the membrane lung" may denote that either one or both of the carbon dioxide emission amount and the oxygen uptake amount in the membrane lung. Another index that can be used to calculate the carbon dioxide emission amount and the oxygen uptake amount may be calculated.

When calculating the carbon dioxide emission amount and the oxygen uptake amount in the membrane lung, it is appropriate that, for example, the carbon dioxide content, the oxygen content, and the gas flow rate of the inspiratory gas and the expiratory gas of the membrane lung are obtained and the calculation is performed using them.

In an embodiment of the invention, the calculation unit may calculate the carbon dioxide emission amount in the membrane lung by inspiratory gas and expiratory gas of the membrane lung.

The calculation unit calculates the carbon dioxide emission amount in the membrane lung based on the inspiratory gas and the expiratory gas of the membrane lung input thereinto, so the carbon dioxide emission amount in the membrane lung can be accurately calculated.

As a result, the oxygen uptake amount in the membrane lung can be appropriately grasped.

The carbon dioxide emission amount in the membrane lung can be calculated by, for example, the following expression.

The carbon dioxide emission amount in the membrane lung may be calculated (approximated) by the following expression.

When calculating the carbon dioxide emission amount using these expressions, it is appropriate that compensation is performed using temperature, pressure, or the like.

In an embodiment of the invention, the calculation unit may calculate the blood gas-exchanging state index based on a gas-exchanging amount of blood in the native lung.

The calculation unit calculates the blood gas-exchanging state index in the native lung, so the gas-exchanging state of blood by the native lung can be accurately grasped.

In an embodiment of the invention, the calculation unit may calculate the gas-exchanging amount of blood in the native lung based on at least one of a carbon dioxide emission amount in the native lung and an oxygen uptake amount in the living body.

The calculation unit calculates the gas-exchanging amount of blood in the native lung based on at least one of the carbon dioxide emission amount in the native lung and the oxygen uptake amount in the native lung, so the gas-exchanging amount of blood in the native lung can be efficiently and accurately calculated.

As a result, the oxygenation status of blood by the native lung can be grasped.

The phrase "at least one of the carbon dioxide emission amount and the oxygen uptake amount in the native lung" denotes the same as in the membrane lung.

In an embodiment of the invention, the calculation unit may calculate the carbon dioxide emission amount in the native lung by inspiratory gas and expiratory gas of the native lung.

The calculation unit calculates the carbon dioxide emission amount in the native lung based on the inspiratory gas and the expiratory gas of the native lung input thereinto, so the carbon dioxide emission amount in the native lung can be accurately calculated.

The carbon dioxide emission amount in the native lung is appropriately calculated by, for example, the following expression.

When calculating the carbon dioxide (CO<NUM>) emission amount by the native lung, for example, the respiratory gas concentration (oxygen concentration, carbon dioxide concentration) in the ventilator may be applied.

In an embodiment of the invention, the calculation unit may calculate the carbon dioxide emission amount in the native lung by volume capno analysis.

The calculation unit calculates the carbon dioxide emission amount in the native lung by generally applicable volume capno analysis, so the carbon dioxide emission amount in the native lung can be efficiently and accurately calculated.

The contribution degree by the assisted circulation to the gas exchange of blood in the living body is expressed by an assisted circulation ratio (ECMO Rate).

The assisted circulation ratio (ECMO Rate) can be calculated by the following expressions. <MAT> <MAT>.

As the gas exchange index in the living body, for example, the total emission amount of carbon dioxide (CO2) generated in the whole living body may be applied.

As an example of the blood-oxygenated state index based on the metabolism estimated (calculated) from the weight of the living body, the carbon dioxide (CO2) amount due to metabolism assumed at rest shown below may be applied.

In an embodiment of the invention, the calculation unit may calculate at set time intervals.

The assisted circulation calculation ratio unit (<NUM>) calculates at set time intervals, so the dynamics of the assisted circulation (ECMO) with respect to the entire respiratory metabolism of the living body can be grasped as a trend.

By accumulating data in chronological order, the dynamics of the assisted circulation (ECMO) can be accurately grasped.

The set time interval may be manually set or may be automatically set so as to correspond to the interval time measured by a sensor or the like, and can be arbitrarily set. It may be calculated and displayed in real time or with a certain time delay.

According to a monitoring apparatus pertaining to the present invention, the oxygenation state of blood in a living body connected with an assisted circulation apparatus can be monitored.

Hereinafter, an assisted circulation (V-V ECMO) pertaining to a first embodiment of the present invention is described with reference to <FIG>.

<FIG> is a conceptual diagram showing a schematic configuration of the assisted circulation (V-V ECMO) pertaining to the first embodiment. The dotted lines shown in <FIG> simplify and denote electric cables connecting sensors and a monitoring apparatus <NUM>. That is, the monitoring apparatus <NUM> is connected to sensors and the like <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> described below through the electric cables or wireless communication and is configured so as to obtain information from these sensors by wire or wirelessly.

In <FIG>, a reference sign <NUM> represents an assisted circulation system (blood circulation circuit) in the assisted circulation (V-V ECMO), a reference sign <NUM> represents the monitoring apparatus, a reference sign <NUM> represents a centrifugal pump (blood transfer pump), a reference sign <NUM> represents a membrane lung, a reference sign <NUM> represents a ventilator, a reference sign <NUM> represents a pulse oximeter (blood oxygenation index-measuring device), and a reference sign <NUM> represents an LCD touch panel.

Hereinafter, the assisted circulation system (blood circulation circuit) is referred to as an assisted circulation system (V-V ECMO).

The first embodiment is an example in which as shown in <FIG>, a patient (living body) is connected with, for example, the assisted circulation system (V-V ECMO) <NUM> and the ventilator <NUM>.

In the first embodiment, as shown in <FIG>, the patient (living body) P is connected with, for example, the monitoring apparatus <NUM>, the assisted circulation system (V-V ECMO) <NUM>, the LCD touch panel <NUM>, the ventilator <NUM>, and the pulse oximeter (blood oxygenation index-measuring device) <NUM>. The monitoring apparatus <NUM> is connected to the patient P through sensors. The LCD touch panel <NUM> of the present embodiment is connected to the monitoring apparatus <NUM>.

As shown in <FIG>, the assisted circulation system (V-V ECMO) <NUM> is configured such that blood removed from a vein V1 of the patient (living body, human body) P is circulated by the centrifugal pump (blood transfer pump) <NUM>, the blood is gas-exchanged in the membrane lung <NUM> and is returned to the vein V1 of the patient P again.

The patient (living body, human body) P is connected with the ventilator <NUM> and inhales inspiratory gas supplied from the ventilator <NUM>, and artificial respiration in which blood is oxygenated in the native lung (NL) thereof is performed.

As shown in <FIG>, the assisted circulation system (V-V ECMO) <NUM> includes, for example, a blood removal line <NUM>, a blood transfer line <NUM>, a blood return line <NUM>, a recirculation line <NUM>, the centrifugal pump (blood transfer pump) <NUM>, a flow sensor <NUM>, the oxygen saturation sensor <NUM>, the blood transfer auto clamp <NUM>, a recirculation clamp <NUM>, and the membrane lung <NUM>.

In the present embodiment, of the configuration of the assisted circulation system <NUM>, the flow sensor <NUM>, the oxygen saturation sensor <NUM>, the blood transfer auto clamp <NUM>, the recirculation clamp <NUM>, and the membrane lung <NUM> configure an assisted circulation apparatus <NUM>. In other words, the assisted circulation system <NUM> includes the assisted circulation apparatus <NUM>, the blood removal line <NUM>, the blood transfer line <NUM>, the blood return line <NUM>, the recirculation line <NUM>, and the centrifugal pump <NUM>, and the components <NUM>, <NUM>, <NUM>, <NUM> and <NUM> can be handled as disposable products.

It is sufficient that the minimum configuration of the assisted circulation apparatus <NUM> includes the flow sensor <NUM>, the oxygen saturation sensor <NUM>, the blood transfer auto clamp <NUM>, the recirculation clamp <NUM>, and the membrane lung <NUM>, and the assisted circulation apparatus <NUM> may be configured to include other components (for example, part of the above lines). The assisted circulation apparatus <NUM> may further include a drive unit 115A that drives the centrifugal pump <NUM>. The drive unit 115A includes, for example, a motor such as an AC servomotor or a DC servomotor as a drive source for the centrifugal pump <NUM>. The drive unit 115A may include a controller configured of a processor or an integrated circuit (IC), which controls the motor. The assisted circulation apparatus <NUM> may further include the monitoring apparatus <NUM>.

As shown in <FIG>, for example, the blood removal line <NUM>, the centrifugal pump <NUM>, the blood transfer line <NUM>, a membrane lung body <NUM>, and the blood return line <NUM> are arranged in this order with respect to the patient P, and the blood removed from the patient P circulates in this order and returns to the patient P in a steady state.

The blood removal line <NUM> includes, for example, a first blood removal line 111A connected to the upstream side (the patient P), and a second blood removal line 111B connected to the downstream side (the centrifugal pump). The blood removal line <NUM> transfers the blood removed from the patient P to the centrifugal pump <NUM>.

The blood transfer line <NUM> transfers blood sent out from, for example, the centrifugal pump <NUM> to the membrane lung <NUM>.

The blood return line <NUM> includes, for example, a first return line 113A connected to the upstream side (the membrane lung), and a second return line 113B connected to the downstream side (the patient P).

The return line <NUM> transfers (returns) blood sent out from the membrane lung <NUM> to the vein V1 of the patient (living body) P.

The flow sensor <NUM> is disposed in the first return line <NUM>.

The recirculation line <NUM> connects two points together, for example, one of the two points is between the first return line 113A and the second return line 113B of the blood return line <NUM>, and the other of the two points is between the first blood removal line 111A and the second blood removal line 111B of the blood removal line <NUM>.

The blood removal line <NUM>, the blood transfer line <NUM>, the return line <NUM>, and the recirculation line <NUM> are formed of tubes made from, for example, flexible resin material.

As shown in <FIG>, the centrifugal pump (blood transfer pump) <NUM> has an inflow side connected to the blood removal line <NUM> and an outflow side connected to the blood transfer line <NUM>, makes impeller blades rotate by, for example, the AC servomotor or the DC servomotor, suctions blood removed from the patient P through the blood removal line <NUM>, and transfers the blood to the membrane lung <NUM> through the blood transfer line <NUM>.

The centrifugal pump <NUM> is configured so as to perform, for example, feedback control using a flow rate (flow speed) detected by the flow sensor <NUM> by operating a flow rate-setting switch (not shown).

As shown in <FIG>, the blood transfer auto clamp <NUM> is disposed in, for example, the return line <NUM>. Specifically, the blood transfer auto clamp <NUM> is disposed in the second return line 113B and is configured to close and open itself (i.e., the second return line 113B) by a clamping portion through, for example, manually operating an actuator.

The blood transfer auto clamp <NUM> is connected to the monitoring apparatus <NUM> by wire or wirelessly and transmits signals indicating the closed state of the blood transfer auto clamp <NUM> to the monitoring apparatus <NUM>.

As shown in <FIG>, the recirculation clamp <NUM> is disposed in, for example, the recirculation line <NUM> and is configured to close and open the recirculation line <NUM> by operating a clamping portion by, for example, a manually operated actuator.

When the blood transfer auto clamp <NUM> opens the second return line 113B, the recirculation clamp <NUM> closes the recirculation line <NUM>, and the removed blood is circulated to the patient P through the blood removal line <NUM>, the blood transfer line <NUM>, and the return line <NUM> without through the recirculation line <NUM>.

For example, in an emergency or the like, when the blood transfer auto clamp <NUM> closes the second return line 113B, the blood flow in the second return line 113B stops, but the recirculation clamp <NUM> opens the recirculation line <NUM>, and the removed blood is circulated through the second blood removal line 111B, the blood transfer line <NUM>, the first return line 113A, and the recirculation line <NUM>. Thereby, even if gas supply to the membrane lung (ML) <NUM> is stopped, the blood circulates and does not stagnate, so blood coagulation can be prevented.

The oxygen saturation sensor (blood oxygenation index sensor) <NUM> includes, for example, a removed blood oxygen saturation sensor disposed in the second blood removal line 111B, and a returning blood oxygen saturation sensor disposed in the first return line 113A.

In <FIG>, only the returning blood oxygen saturation sensor is represented by the reference sign <NUM> for the sake of simplicity.

In the present embodiment, the oxygen saturation sensor (returning blood oxygen saturation sensor) <NUM> is connected to the monitoring apparatus <NUM> by cables (not shown), detects the oxygen saturation degree and hemoglobin amount of blood sent out from the membrane lung body <NUM> and flowing in the first return line 113A, and transmits them to the monitoring apparatus <NUM>.

In the present embodiment, the oxygen saturation sensor <NUM> is configured so as to detect the oxygenation index (oxygenation degree, blood oxygenation index) of hemoglobin in blood by infrared radiation, for example.

The configuration of the oxygen saturation sensor <NUM> can be arbitrarily set as long as the degree of blood oxygenation can be detected, and known various sensors capable of measuring the blood oxygenation index may be applied thereto.

As shown in <FIG>, the membrane lung <NUM> includes, for example, the membrane lung body <NUM>, a membrane lung inspiratory line <NUM>, a membrane lung expiratory line <NUM>, the membrane lung inspiratory gas sensor <NUM>, and the membrane lung expiratory gas sensor <NUM> and is connected to a membrane lung gas supply device <NUM>.

The membrane lung <NUM> is configured to oxygenate the blood flowing through the assisted circulation system (V-V ECMO) <NUM>.

The membrane lung body <NUM> includes, for example, a hollow fiber membrane, a flat membrane or the like having excellent gas permeability.

The membrane lung body <NUM> is configured such that in the hollow fiber membrane, the flat membrane or the like, oxygen of the supplied gas moves to the blood, and carbon dioxide dissolved in the blood moves to the gas supplied to the membrane lung, thereby gas-exchanging the blood. The membrane lung body <NUM> is integrated with, for example, a heat exchanger for adjusting the temperature of blood.

The configuration of the membrane lung body <NUM> can be arbitrarily set as long as the gas exchange of blood can be performed.

The membrane lung gas supply device <NUM> supplies gas having an oxygen (O<NUM>) concentration adjusted to be suitable for the gas exchange to the membrane lung body <NUM>. In the present embodiment, for example, the oxygen (O<NUM>) concentration of the gas is adjusted to <NUM>%.

The membrane lung inspiratory line <NUM> includes, for example, a first inspiratory line 123A connected to the membrane lung gas supply device <NUM>, and a second inspiratory line 123B connected to the membrane lung body <NUM>.

The membrane lung inspiratory line <NUM> transfers the membrane lung inspiratory gas sent out from the membrane lung gas supply device <NUM> to the membrane lung body <NUM>.

The membrane lung expiratory line <NUM> releases the expiratory gas discharged from the membrane lung body <NUM> to the outside of the system.

The membrane lung inspiratory line <NUM> and the membrane lung expiratory line <NUM> are formed of tubes made from, for example, flexible resin material.

In the present embodiment, the membrane lung inspiratory gas sensor <NUM> is configured of, for example, a carbon dioxide (CO<NUM>) sensor.

The membrane lung inspiratory gas sensor <NUM> is disposed in the membrane lung inspiratory line <NUM>. Specifically, the membrane lung inspiratory gas sensor <NUM> is disposed between the first membrane lung inspiratory line 123A and the second membrane lung inspiratory line 123B.

The membrane lung inspiratory gas sensor <NUM> detects the carbon dioxide (CO<NUM>) concentration (oxygen content parameter) of the inspiratory gas to be sent into the membrane lung body <NUM> through the membrane lung inspiratory line <NUM>.

In the present embodiment, the membrane lung expiratory gas sensor <NUM> is configured of, for example, a carbon dioxide (CO<NUM>) sensor.

The membrane lung expiratory gas sensor <NUM> is disposed in the membrane lung expiratory line <NUM>. Specifically, the membrane lung expiratory gas sensor <NUM> is disposed at the downstream end of the membrane lung expiratory line <NUM>.

The membrane lung expiratory gas sensor <NUM> detects the carbon dioxide (CO<NUM>) concentration (oxygen content parameter) contained in the expiratory gas discharged from the membrane lung body <NUM> through the membrane lung expiratory line <NUM>.

The configurations of the membrane lung inspiratory gas sensor <NUM> and the membrane lung expiratory gas sensor <NUM> can be arbitrarily set, and for example, oxygen (O<NUM>) sensors may be applied thereto instead of the carbon dioxide (CO<NUM>) sensors. Known various sensors may be applied to the membrane lung inspiratory gas sensor <NUM> and the membrane lung expiratory gas sensor <NUM> as long as the sensors can detect concentration parameters such as the partial pressure of carbon dioxide (CO<NUM>), which are used to determine the carbon dioxide (CO<NUM>) concentration of the inspiratory gas and the expiratory gas.

For example, it may be configured that a sampling circuit (not shown) is provided in the membrane lung inspiratory line <NUM> and the membrane lung expiratory line <NUM>, the sampling line thereof is switched between the membrane lung inspiratory line <NUM> and the membrane lung expiratory line <NUM>, and thereby one gas sensor operates as both of the membrane lung expiratory gas sensor <NUM> and the membrane lung expiratory gas sensor <NUM>.

As shown in <FIG>, the ventilator <NUM> is connected to the patient P through, for example, a ventilator inspiratory line <NUM> and a ventilator expiratory line <NUM>.

The ventilator <NUM> is configured to supply ventilator gas having an increased oxygen (O<NUM>) concentration to the patient (living body) P to assist efficient gas exchange of blood in the patient P.

Although the configuration of the ventilator <NUM> can be arbitrarily set, in the present embodiment, the ventilator <NUM> is configured to include, for example, a gas circuit, an inspiratory valve, an expiratory valve, a pressure-controlling circuit, a flow rate-controlling circuit, and a display unit, the gas circuit includes a pressure-reducing valve, and the display unit is also used as an input interface (I/O).

The ventilator inspiratory line <NUM> transfers ventilator inspiratory gas sent out from the ventilator <NUM> to the native lung (NL) of the patient P.

As shown in <FIG>, for example, the ventilator inspiratory gas sensor <NUM> is disposed in the ventilator inspiratory line <NUM> and can detect the carbon dioxide (CO<NUM>) concentration (oxygen content parameter) of the inspiratory gas to be supplied from the inspirator <NUM> through the ventilator inspiratory line <NUM> to the patient P.

The ventilator expiratory line <NUM> transfers the expiratory gas discharged from the native lung (NL) of the patient P to the ventilator <NUM>.

As shown in <FIG>, for example, the ventilator expiratory gas sensor <NUM> is disposed in the ventilator expiratory line <NUM> and can detect the carbon dioxide (CO<NUM>) concentration (oxygen content parameter) of the expiratory gas after the oxygenation of blood discharged from the patient P and to be transferred to the ventilator <NUM> through the ventilator expiratory line <NUM>.

Hereinafter, the operation of the assisted circulation system (V-V ECMO) is described with reference to <FIG>, <FIG> and <FIG>.

<FIG> is a conceptual diagram showing an overview of blood circulation of a patient (living body) P without the assisted circulation system (V-V ECMO) applied thereto, and <FIG> is a conceptual diagram showing an overview of blood circulation of a patient P having the assisted circulation system (ECMO) applied thereto. In <FIG> and <FIG>, a blood flow between the heart and the native lung is omitted.

In <FIG> and <FIG>, white arrows indicate the flow of blood after the gas exchange, and filled arrows indicate the flow of blood before the gas exchange.

First, with reference to <FIG>, the blood circulation in a case where the assisted circulation system (ECMO) is not applied is described.

When the assisted circulation system (ECMO) is not applied, in the blood circulation in the patient (living body) P, as shown in <FIG>, blood having an oxygen content (oxygen content parameter) CaO<NUM> and an oxygen saturation degree (blood-oxygenated state index) SaO<NUM> after it is oxygenated in the native lung (NL) is sent out by the heart through an artery A1 to the living tissue PS of the whole body.

In the blood delivered to the living tissue PS, part of the oxygen (O<NUM>) in the blood is consumed by metabolism, carbon dioxide (CO<NUM>) is generated, and the oxygen content and the oxygen saturation degree thereof decrease to an oxygen content (oxygen content parameter) CvO<NUM> and an oxygen saturation degree (blood-oxygenated state index) SvO<NUM>.

The blood returns to the heart and the native lung (NL) through the vein V1.

In this blood circulation, blood flows through the artery A1 and the vein V1 at, for example, an equal flow rate Qco.

Next, with reference to <FIG>, the blood circulation in a case where the assisted circulation system (ECMO) is applied is described.

In the patient (living body) P having the assisted circulation system (V-V ECMO) <NUM> applied thereto, as shown in <FIG>, blood oxygenated in the native lung (NL) and having an oxygen content (oxygen content parameter) CaO<NUM>, an oxygen saturation degree (blood-oxygenated state index) SaO<NUM>, and a flow rate (cardiac output) Qco is sent out by the heart through the artery A1 to the living tissue PS of the whole body.

Blood gas-exchanged (metabolized) in the living tissue PS and having an oxygen content (oxygen content parameter) CvO<NUM>, an oxygen saturation degree (blood-oxygenated state index) SvO<NUM>, and a flow rate (equivalent to the cardiac output) Qco flows through the vein V1 toward the heart and the native lung, and blood with a flow rate QECMO is removed from a blood removal point P1 and flows to the membrane lung (ML) of the assisted circulation system (V-V ECMO) <NUM>.

On the other hand, blood not removed from the blood removal point P and having a flow rate QCOP (= QCO-QECMO) flows directly toward the heart through the vein V1.

QRE shown in <FIG> denotes the flow rate of blood recirculated in the assisted circulation (V-V ECMO), which is oxygenated and returned to the vein V1 and thereafter flows into the membrane lung (ML) again.

The removed blood is sent to the membrane lung (ML), is gas-exchanged and oxygenated in the membrane lung (ML), and is returned to the vein V1 at a return point P2.

The blood returned to the vein V1 at the return point P2 is mixed with blood flowed through the vein V1 and having the oxygen content CvO<NUM> and the oxygen saturation degree SvO<NUM> to become blood having an oxygen content (oxygen content parameter) CvO<NUM> (NL), an oxygen saturation degree (blood-oxygenated state index) SvO<NUM> (NL), and the flow rate Qco and to be delivered to the native lung (NL).

The blood is oxygenated in the native lung (NL) to become blood having the oxygen content CaO<NUM> and the oxygen saturation degree SaO<NUM>, and is sent out to the artery A1.

At this time, the blood sent out to the artery A1 is oxygenated by, for example, an oxygen uptake amount V'O<NUM> (ML) in the membrane lung (ML) and is oxygenated by oxygen (O<NUM>) having an oxygen uptake amount V'O<NUM> (NL) in the native lung (NL).

The contribution degree of the assisted circulation (ECMO) to the living body can be expressed by, for example, the following assisted circulation ratio (ECMO Rate).

For example, when the assisted circulation ratio (ECMO Rate) is expressed with a focus on the oxygen uptake amount, the following expression is obtained.

That is, the contribution degree of the assisted circulation (ECMO) to the living body can be expressed by a ratio of the gas-exchanging amount of blood in the membrane lung (ML) to the total of the gas-exchanging amount of blood in the membrane lung (ML) and the gas-exchanging amount in the native lung (NL).

The oxygen uptake amount V'O<NUM> (NL) in the native lung (NL) can be obtained as the oxygen content contained in respiratory gas of the patient (living body).

When the assisted circulation ratio (ECMO Rate) is expressed with a focus on the carbon dioxide emission amount, the following expression is obtained.

The carbon dioxide emission amount V'CO<NUM> (NL) in the native lung (NL) can be obtained as the carbon dioxide content contained in respiratory gas of the patient (living body).

Regarding the blood circulation shown in <FIG>, it is possible to confirm the gas-exchanging state of blood by calculating using, for example, Formulas [<NUM>] to (<NUM>) shown below.

First, Formula (<NUM>) shows the relationship between the oxygen uptake amount in the membrane lung (ML) and the native lung (NL) and the amount [DaO<NUM>-DvO<NUM>] of oxygen consumed in the living tissue. [Expression <NUM>] <MAT>.

When transforming Formula (<NUM>), following Formula (<NUM>) holds. [Expression <NUM>] <MAT>.

The oxygen transfer rate DvO<NUM> of blood flowing through the vein V1 shown in <FIG> can be expressed by following Formula (<NUM>). [Expression <NUM>] <MAT>.

The oxygen uptake amount in the membrane lung (ML) is QECMO × (the oxygen content CaO<NUM> (ML) of blood oxygenated in the membrane lung (ML) - the oxygen content CvO<NUM> (ML) before being oxygenated in the membrane lung (ML)), so the oxygen content CaO<NUM> (ML) is expressed by following Formula (<NUM>). [Expression <NUM>] <MAT>.

When substituting Formula (<NUM>) for Formula (<NUM>), the blood oxygen transfer rate DaO<NUM> of the cardiac output flowing through the artery A1 is expressed as following Formula (<NUM>). [Expression <NUM>] <MAT>.

The oxygen uptake amount DaO<NUM>-DvO<NUM> in the membrane lung (ML) and the native lung (NL) corresponds to the oxygen uptake amount in the membrane lung (ML) and the native lung (NL). Since the oxygen uptake amount corresponds to the carbon dioxide emission amount, when focusing on the carbon dioxide emission amount, following Formula (<NUM>) is derived out. The oxygen uptake amount and the carbon dioxide emission amount are the gas exchange index of blood. [Expression <NUM>] <MAT>.

The monitoring apparatus <NUM> described below may appropriately calculate whether or not an index can be calculated by above Formulas (<NUM>) to (<NUM>), and it may be displayed on the LCD touch panel <NUM>.

Next, the schematic configurations of the monitoring apparatus <NUM> and the LCD touch panel <NUM> are described with reference to <FIG>. <FIG> is a block diagram showing the schematic configuration of the monitoring apparatus pertaining to the first embodiment, <FIG> are flowcharts showing outlines of calculating procedures in the monitoring apparatus, and <FIG> is a conceptual diagram showing the schematic configuration of the LCD touch panel connected to the monitoring apparatus.

Although the configurations of the monitoring apparatus <NUM> and the LCD touch panel <NUM> can be arbitrarily set, in the present embodiment, the monitoring apparatus <NUM> can calculate the assisted circulation ratio (ECMO Rate) in the assisted circulation system (V-V ECMO) <NUM> and compare the oxygen saturation degree (blood-oxygenated state index) of blood of the patient (living body) P therewith.

As shown in <FIG>, the monitoring apparatus <NUM> includes, for example, a first signal reception unit <NUM> to a sixth signal reception unit <NUM>, a first calculation unit <NUM>, a second calculation unit <NUM>, and a first storage unit <NUM> and is configured so as to perform various calculations at set time intervals. The signal reception units <NUM> to <NUM> are, for example, input ports.

In the present embodiment (and a second embodiment described below), the monitoring apparatus <NUM> may be configured to include the first signal reception unit <NUM> to the sixth signal reception unit <NUM>, the first calculation unit <NUM>, and the second calculation unit <NUM> without including the first storage unit <NUM>. That is, a component corresponding to the first storage unit <NUM> may be connected to the monitoring apparatus <NUM> by wire or wirelessly, and they may be configured to transmit and receive information therebetween. The monitoring apparatus <NUM> may also be configured to include the LCD touch panel <NUM>.

In the present embodiment, the monitoring apparatus <NUM> is configured to calculate using signals input from the sensors in real time and output the results.

As shown in <FIG>, the monitoring apparatus <NUM> is connected to the membrane lung inspiratory gas sensor <NUM>, the membrane lung expiratory gas sensor <NUM>, the ventilator inspiratory gas sensor <NUM>, the ventilator expiratory gas sensor <NUM>, the oxygen saturation sensor <NUM>, and the pulse oximeter <NUM> through cables and is configured such that signals are appropriately input thereinto from them. The monitoring apparatus <NUM> may be configured so as to obtain information measured by at least one of the sensors <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and <NUM> through wireless communication without through cables. The monitoring apparatus <NUM> may include a receiver that receives information measured by the sensors.

The first signal reception unit <NUM> is connected to the membrane lung inspiratory gas sensor <NUM> and is configured to receive a membrane lung inspiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal indicating the carbon dioxide concentration contained in membrane lung inspiratory gas, which is sent from the membrane lung inspiratory gas sensor <NUM>.

The second signal reception unit <NUM> is connected to the membrane lung expiratory gas sensor <NUM> and is configured to receive a membrane lung expiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal indicating the carbon dioxide concentration contained in membrane lung expiratory gas, which is sent from the membrane lung expiratory gas sensor <NUM>.

The third signal reception unit <NUM> is connected to the ventilator inspiratory gas sensor <NUM> and is configured to receive an inspiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal indicating the carbon dioxide concentration contained in inspiratory gas to be delivered from the ventilator <NUM> to the native lung (NL), which is sent from the ventilator inspiratory gas sensor <NUM>.

The fourth signal reception unit <NUM> is connected to the ventilator expiratory gas sensor <NUM> and is configured to receive an expiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal indicating the carbon dioxide concentration contained in expiratory gas discharged from the native lung (NL), which is sent from the ventilator expiratory gas sensor <NUM>.

The fifth signal reception unit <NUM> is connected to the oxygen saturation sensor <NUM> and is configured to receive an oxygen saturation (blood-oxygenated state index) signal indicating the oxygen saturation degree of blood after being oxygenated by the membrane lung <NUM>, which is sent from the oxygen saturation sensor <NUM>.

The sixth signal reception unit <NUM> is connected to the pulse oximeter <NUM> and is configured to receive an oxygen saturation (blood-oxygenated state index) signal indicating the oxygen saturation degree of blood of the patient (living body, human body) P, which is sent from the pulse oximeter <NUM>.

The first signal reception unit <NUM> to the sixth signal reception unit <NUM> output the received signals to the first calculation unit <NUM>.

The first calculation unit <NUM> is configured of a computer and is connected to the first signal reception unit <NUM> to the sixth signal reception unit <NUM> as shown in <FIG> so that signals are input thereinto from these signal reception units. In the present embodiment (and the second embodiment described below), the computer means a configuration including at least a processor such as a CPU, and a memory capable of storing programs executable by the processor.

The first calculation unit <NUM> is configured such that gas flow rate signals (not shown) of the inspiratory gas and the expiratory gas are input thereinto from the membrane lung <NUM> and the ventilator <NUM> through cables (not shown).

In the present embodiment, gas supply amounts of the membrane lung <NUM> and the ventilator <NUM> are used as the gas flow rates of the inspiratory gas and the expiratory gas.

The first calculation unit <NUM> is connected to, for example, the first storage unit <NUM>.

As shown in <FIG>, the first calculation unit <NUM> includes, for example, a membrane lung carbon dioxide emission calculation unit <NUM>, a ventilator carbon dioxide emission calculation unit <NUM>, a membrane lung oxygen saturation (blood-oxygenated state index) calculation unit <NUM>, and a living body oxygen saturation (blood-oxygenated state index) calculation unit <NUM>.

The first calculation unit <NUM> refers to the first storage unit <NUM> as necessary and calculates various parameters based on signals input through the first signal reception unit <NUM> to the sixth signal reception unit <NUM>. The first calculation unit <NUM> outputs the calculated results to the second calculation unit <NUM>.

The first storage unit <NUM> is configured of, for example, a memory, a solid state drive (SSD), a hard disk drive or the like.

The first storage unit <NUM> stores constants, data tables, formulas for calculations, or the like, to which the membrane lung carbon dioxide emission calculation unit <NUM>, the ventilator carbon dioxide emission calculation unit <NUM>, the membrane lung oxygen saturation calculation unit <NUM>, and the living body oxygen saturation calculation unit <NUM> refer at the time of calculating.

The second calculation unit <NUM> is configured of a computer and is connected to the first calculation unit <NUM> as shown in <FIG> so that the calculated results are input thereinto from the first calculation unit <NUM>.

The second calculation unit <NUM> includes, for example, an assisted circulation ratio (assisted circulation contribution degree) calculation unit <NUM>, and an oxygen saturation (blood-oxygenated state index) display unit <NUM>.

As shown in <FIG>, the membrane lung carbon dioxide emission calculation unit <NUM> receives a membrane lung inspiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal and a membrane lung expiratory carbon dioxide (CO<NUM>) concentration (oxygen content parameter) signal through the first signal reception unit <NUM> and the second signal reception unit <NUM>.

The membrane lung carbon dioxide emission calculation unit <NUM> receives a gas supply amount (i.e., gas flow rates of the inspiratory gas and the expiratory gas) signal (not shown) of the membrane lung <NUM>.

The membrane lung carbon dioxide emission calculation unit <NUM> calculates the carbon dioxide (CO<NUM>) emission amount (V'CO<NUM> (ML)) of the membrane lung <NUM> based on the received carbon dioxide (CO<NUM>) concentration signals indicating the carbon dioxide concentrations contained in the inspiratory gas and the expiratory gas, and the received gas supply amount of the membrane lung <NUM>.

Specifically, according to the following procedure shown in <FIG>, the carbon dioxide (CO<NUM>) concentration difference of the membrane lung <NUM> is calculated from the carbon dioxide (CO<NUM>) concentration contained in the inspiratory gas of the membrane lung <NUM> and the carbon dioxide (CO<NUM>) concentration contained in the expiratory gas thereof, the product of the carbon dioxide (CO<NUM>) concentration difference occurring in the membrane lung <NUM> multiplied by the gas supply amount of the membrane lung <NUM> is calculated, and the carbon dioxide emission amount (V'CO<NUM> (ML)) of the membrane lung <NUM> is calculated.

The membrane lung carbon dioxide emission amount can be calculated by, for example, the following expression.

At the time the above steps (S101) to (S105) are executed, the data tables (not shown) stored in the first storage unit <NUM> are referenced as necessary.

The membrane lung carbon dioxide emission calculation unit <NUM> outputs the membrane lung inspiratory carbon dioxide (CO<NUM>) concentration signal, the membrane lung expiratory carbon dioxide (CO<NUM>) concentration signal, the membrane lung gas supply amount signal, and the calculated carbon dioxide emission amount (V'CO<NUM> (ML)) in the membrane lung to the assisted circulation ratio calculation unit <NUM>.

As shown in <FIG>, the ventilator carbon dioxide emission calculation unit <NUM> receives a ventilator inspiratory carbon dioxide (CO<NUM>) concentration signal and a ventilator carbon dioxide (CO<NUM>) concentration signal through the third signal reception unit <NUM> and the fourth signal reception unit <NUM>.

The ventilator carbon dioxide emission calculation unit <NUM> receives a gas supply amount (i.e., gas flow rates of the inspiratory gas and the expiratory gas) signal (not shown) from the ventilator <NUM>.

The ventilator carbon dioxide emission calculation unit <NUM> calculates the carbon dioxide (CO<NUM>) emission amount (V'CO<NUM> (NL)) in the native lung (NL) based on the received carbon dioxide (CO<NUM>) concentration signals indicating the carbon dioxide concentration contained in the inspiratory gas and the expiratory gas.

Specifically, according to the following procedure shown in <FIG>, the carbon dioxide (CO<NUM>) concentration difference in the ventilator <NUM> is calculated from the carbon dioxide (CO<NUM>) concentration contained in the inspiratory gas of the ventilator <NUM> and the carbon dioxide (CO<NUM>) concentration contained in the expiratory gas thereof, the product of the carbon dioxide (CO<NUM>) concentration difference occurring in the ventilator <NUM> multiplied by the gas supply amount of the ventilator <NUM> is calculated, and the carbon dioxide emission amount (V'CO<NUM> (NL)) of the ventilator <NUM> is calculated. The carbon dioxide emission amount of the ventilator <NUM> is the carbon dioxide emission amount of the native lung (NL).

The ventilator carbon dioxide emission amount can be calculated by, for example, the following expression.

At the time the above steps (S201) to (S205) are executed, the data tables (not shown) stored in the first storage unit <NUM> are referenced as necessary.

In the present embodiment, the carbon dioxide emission amount (V'CO<NUM> (NL)) of the native lung (NL) is calculated by the volume capno analysis or the like.

The ventilator carbon dioxide emission calculation unit <NUM> outputs the ventilator inspiratory carbon dioxide (CO<NUM>) concentration signal, the ventilator expiratory carbon dioxide (CO<NUM>) concentration signal, the ventilator gas supply amount signal, and the calculated carbon dioxide emission amount (V'CO<NUM> (NL)) in the native lung (NL) to the assisted circulation ratio calculation unit <NUM>.

As shown in <FIG>, the membrane lung oxygen saturation (blood-oxygenated state index) calculation unit <NUM> receives an oxygen saturation (blood-oxygenated state index) signal indicating the oxygen saturation degree of blood oxygenated in the membrane lung <NUM> from the oxygen saturation sensor <NUM> through the fifth signal reception unit <NUM>.

The membrane lung oxygen saturation calculation unit <NUM> refers to, for example, the data tables (not shown) stored in the first storage unit <NUM> as necessary, calculates the membrane lung oxygen saturation degree (blood-oxygenated state index of the membrane lung) contained in the expiratory gas of the membrane lung <NUM>, and outputs it to the oxygen saturation display unit <NUM>.

As shown in <FIG>, the living body oxygen saturation (blood-oxygenated state index) calculation unit <NUM> receives an oxygen saturation (blood-oxygenated state index) signal indicating the oxygen saturation degree of blood in the patient (living body) P from the pulse oximeter <NUM> through the sixth signal reception unit <NUM>.

The living body oxygen saturation calculation unit <NUM> refers to, for example, the data tables (not shown) stored in the first storage unit <NUM> as necessary, calculates the oxygen saturation degree (blood-oxygenated state index) of the patient (living body) P, and outputs it to the oxygen saturation (blood-oxygenated state index) display unit <NUM>.

The assisted circulation ratio (assisted circulation contribution degree) calculation unit <NUM> calculates the total emission amount of carbon dioxide (CO<NUM>) of the whole living body, the assisted circulation ratio (ECMO Rate) (contribution degree of the assisted circulation) in the assisted circulation (V-V ECMO), and the respiratory efficiency by the weight of the patient (living body) P based on signals sent from the membrane lung carbon dioxide emission calculation unit <NUM> and the ventilator carbon dioxide emission calculation unit <NUM>.

Specifically, the assisted circulation ratio calculation unit <NUM> calculates, according to the following procedure shown in <FIG>, the carbon dioxide (CO<NUM>) total emission amount of the whole living body from the membrane lung carbon dioxide (CO<NUM>) emission amount and the ventilator carbon dioxide (CO<NUM>) emission amount, and then calculates the assisted circulation ratio (ECMO Rate).

The assisted circulation ratio (ECMO Rate) is calculated by, for example, the following expression.

The assisted circulation ratio calculation unit <NUM> calculates, according to the following procedure shown in <FIG>, the carbon dioxide (CO<NUM>) total emission amount of the whole living body from the membrane lung carbon dioxide (CO<NUM>) emission amount and the ventilator carbon dioxide (CO<NUM>) emission amount, and calculates the respiratory efficiency by the weight of the patient P.

The respiratory efficiency by the weight of the native lung function of the patient P can be calculated by, for example, the following expression.

The assisted circulation ratio (assisted circulation contribution degree) calculation unit <NUM> outputs, for example, the membrane lung inspiratory carbon dioxide concentration, the membrane lung expiratory carbon dioxide concentration, the membrane lung gas supply amount, the membrane lung carbon dioxide emission amount, the ventilator inspiratory carbon dioxide concentration, the ventilator expiratory carbon dioxide concentration, the ventilator gas supply amount, the ventilator carbon dioxide emission amount, the assisted circulation ratio (ECMO Rate), and the respiratory efficiency by the weight of the native lung function of the patient P to the LCD touch panel (display) <NUM> continuously in real time.

The monitoring apparatus <NUM> may be configured to obtain parameters with regard to oxygen (O<NUM>) instead of carbon dioxide (CO<NUM>), and the assisted circulation ratio (assisted circulation contribution degree) calculation unit <NUM> may be configured to output, for example, the membrane lung inspiratory oxygen concentration, the membrane lung expiratory oxygen concentration, the membrane lung gas supply amount, the membrane lung oxygen uptake amount, the ventilator inspiratory oxygen concentration, the ventilator expiratory oxygen concentration, the ventilator gas supply amount, the native lung oxygen uptake amount, the assisted circulation ratio (ECMO Rate), and the respiratory efficiency by the weight of the native lung function of the patient P to the LCD touch panel (display) <NUM> continuously in real time.

The oxygen saturation display unit <NUM> receives the membrane lung oxygen saturation degree from the membrane lung oxygen saturation calculation unit <NUM> and receives the oxygen saturation degree of the patient (living body) P from the living body oxygen saturation calculation unit <NUM>, for example.

The oxygen saturation display unit <NUM> outputs, for example, the membrane lung oxygen saturation degree and the oxygen saturation degree of the patient (living body) P to the LCD touch panel <NUM> and causes the LCD touch panel <NUM> to display them.

The oxygen saturation display unit <NUM> may be configured to compare the membrane lung oxygen saturation degree and the oxygen saturation degree of the patient (living body) P with thresholds and to output alarms when abnormalities such as the degrees falling below the set thresholds are detected.

The thresholds are input using, for example, a numeric keypad (not shown) provided on the LCD touch panel <NUM> and are stored in a storage unit (not shown).

The oxygen saturation display unit <NUM> outputs signals relating to, for example, the membrane lung oxygen saturation degree, the living body oxygen saturation degree, and the alarms to the LCD touch panel (display) <NUM> in real time.

In the present embodiment, although the plurality of calculation units <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> and the display unit <NUM> are described, each or ones of these components may be configured of one computer, and the first calculation unit <NUM> and the second calculation unit <NUM> may be integrally configured of one computer.

As shown in <FIG>, the LCD touch panel <NUM> includes, for example, a membrane lung respiration display section <NUM>, a ventilator respiration display section <NUM>, a carbon dioxide emission (living body-oxygenated state index) display section <NUM> indicating the carbon dioxide emission amount of the living body, a carbon dioxide metabolism display section <NUM> indicating the carbon dioxide metabolism of the living body calculated from the weight thereof, an assisted circulation ratio (ECMO Rate) display section <NUM>, a respiratory efficiency display section <NUM> indicating the respiratory efficiency by the weight, an oxygen saturation (blood-oxygenated state index) display section <NUM>, a graph display section <NUM>, and a panel switch section (operation section) <NUM>.

As shown in <FIG>, the membrane lung respiration display section <NUM> includes, for example, a membrane lung inspiratory carbon dioxide (CO<NUM>) concentration (membrane lung inspiratory gas concentration) display section 181A, a membrane lung expiratory carbon dioxide (CO<NUM>) concentration (membrane lung expiratory gas concentration) display section 181B, a membrane lung gas supply (membrane lung inspiratory and expiratory gas flow rates) display section 181C, and a membrane lung carbon dioxide (CO<NUM>) emission (gas exchange index) display section 181D.

In the present embodiment, the membrane lung inspiratory carbon dioxide (CO<NUM>) concentration display section 181A, the membrane lung expiratory carbon dioxide (CO<NUM>) concentration display section 181B, the membrane lung gas supply display section 181C, and the membrane lung carbon dioxide (CO<NUM>) emission display section 181D display the membrane lung inspiratory carbon dioxide (CO<NUM>) concentration, the membrane lung expiratory carbon dioxide (CO<NUM>) concentration, the membrane lung gas supply amount, and the membrane lung carbon dioxide (CO<NUM>) emission amount, which are output by the assisted circulation ratio calculation unit <NUM>.

As shown in <FIG>, the ventilator respiration display section <NUM> includes, for example, a ventilator inspiratory carbon dioxide (CO<NUM>) concentration (ventilator inspiratory gas concentration) display section 182A, a ventilator expiratory carbon dioxide (CO<NUM>) concentration (ventilator expiratory gas concentration) display section 182B, a ventilator gas supply (ventilator inspiratory and expiratory gas flow rates) display section 182C, and a native lung carbon dioxide emission (gas exchange index) display section 182D.

In the present embodiment, the ventilator inspiratory carbon dioxide (CO<NUM>) concentration display section 182A, the ventilator expiratory carbon dioxide (CO<NUM>) concentration display section 182B, the ventilator gas supply display section 182C, and the native lung carbon dioxide (CO<NUM>) emission (gas exchange index) display section 182D display the ventilator inspiratory carbon dioxide (CO<NUM>) concentration, the ventilator expiratory carbon dioxide (CO<NUM>) concentration, the ventilator gas supply amount, and the carbon dioxide (CO<NUM>) emission amount in native lung (NL), which are output by the assisted circulation ratio calculation unit <NUM>.

The carbon dioxide metabolism display section <NUM> of the living body displays, for example, the carbon dioxide (CO<NUM>) amount by the metabolism of the patient P output by the assisted circulation ratio calculation unit <NUM>.

The assisted circulation ratio (ECMO Rate) display section <NUM> displays, for example, the assisted circulation ratio (ECMO Rate) output by the assisted circulation ratio calculation unit <NUM> numerically.

The respiratory efficiency display section <NUM> by the weight displays, for example, the respiratory efficiency by the weight of the patient P output by the assisted circulation ratio calculation unit <NUM> numerically.

The oxygen saturation display section <NUM> includes, for example, a membrane lung oxygen saturation display section 187A displaying the oxygen saturation degree of the membrane lung <NUM>, and a living body oxygen saturation display section 187B displaying the oxygen saturation degree of the patient (living body) P.

The membrane lung oxygen saturation display section 187A and the living body oxygen saturation display section 187B receive oxygen saturation signals of the membrane lung <NUM> and the patient (living body) P output by the oxygen saturation display unit <NUM> and display them numerically.

As shown in <FIG>, the graph display section <NUM> includes, for example, an assisted circulation ratio (ECMO Rate) display section 188A, and a living body and membrane lung oxygen saturation display section 188B.

The assisted circulation ratio (ECMO Rate) display section 188A displays, for example, a graph A of the assisted circulation ratio (ECMO Rate) output by the assisted circulation ratio calculation unit <NUM> in real time and chronologically.

The living body and membrane lung oxygen saturation display section 188B displays, for example, a graph B1 of the oxygen saturation degree of the membrane lung <NUM> output by the oxygen saturation display unit <NUM>, and a graph B2 of the oxygen saturation degree of the patient (living body) P in real time and chronologically.

As shown in <FIG>, the panel switch section (operation section) <NUM> includes, for example, a first touch portion 189A, a second touch portion 189B, and a third touch portion 189C.

The first touch portion 189A can determine which the oxygen (O<NUM>), the carbon dioxide (CO<NUM>), or both of the oxygen (O<NUM>) and the carbon dioxide (CO<NUM>) is used as the gas exchange index at the time the monitoring apparatus <NUM> monitors the assisted circulation (V-V ECMO) by, for example, operating a graphical user interface (GUI).

The second touch portion 189B can determine which the contribution degree of the assisted circulation (V-V ECMO) is displayed using, for example, the assisted circulation ratio (ECMO Rate) or a ratio of the membrane lung gas-exchanging amount to the ventilator gas-exchanging amount (the membrane lung gas-exchanging amount: the ventilator gas-exchanging amount) by touch operation.

The third touch portion 189C can selectively display, for example, the calculation results of Formulas (<NUM>) to (<NUM>).

According to the monitoring apparatus <NUM> pertaining to the first embodiment, the carbon dioxide emission amount in the assisted circulation system (V-V ECMO) <NUM> and the carbon dioxide emission amount by the ventilator <NUM> can be calculated.

According to the monitoring apparatus <NUM>, in the assisted circulation system (V-V ECMO) <NUM>, based on the membrane lung carbon dioxide emission amount, the native lung carbon dioxide emission amount, and the carbon dioxide total emission amount of the whole living body, the assisted circulation ratio (ECMO Rate) is calculated in real time and is displayed on the graph display section <NUM> of the LCD touch panel <NUM>, so the contribution degree of the membrane lung <NUM> to the gas exchange of the patient P can be accurately grasped as a trend.

The dynamics of the assisted circulation (ECMO) and the status of the assisted circulation with respect to the overall respiration of the patient (living body) P can be accurately confirmed.

As a result, the gas-exchanging state of blood in the native lung (NL) and the membrane lung <NUM> can be accurately grasped.

According to the monitoring apparatus <NUM>, the carbon dioxide emission amount in the membrane lung <NUM> is calculated based on the inspiratory gas and the expiratory gas of the membrane lung <NUM>, so the carbon dioxide emission amount in the membrane lung <NUM> can be accurately calculated.

According to the monitoring apparatus <NUM>, the carbon dioxide emission amount in the native lung (NL) is calculated based on the inspiratory gas and the expiratory gas of the ventilator <NUM>, so the carbon dioxide emission amount in the native lung can be accurately and easily calculated.

As a result, the oxygenation status of blood by the native lung can be efficiently grasped.

According to the monitoring apparatus <NUM>, the carbon dioxide emission amount in the native lung (NL) is calculated by the volume capno analysis, so the carbon dioxide emission amount in the native lung (NL) can be efficiently and accurately calculated.

According to the monitoring apparatus <NUM>, the carbon dioxide (CO<NUM>) amount due to the metabolism of the patient P calculated from the weight of the patient P is compared with the carbon dioxide total emission amount, so it is possible to efficiently grasp whether or not the gas exchange of blood of the patient P is appropriately performed.

According to the monitoring apparatus <NUM>, the respiratory efficiency by the weight of the patient P is calculated based on the carbon dioxide (CO<NUM>) metabolism amount calculated from the weight of the patient P, so it is possible to efficiently grasp whether or not the gas exchange of blood of the patient P is appropriately performed.

Hereinafter, an assisted circulation (V-A ECMO) pertaining to the second embodiment of the present invention is described with reference to <FIG> and <FIG>. In the description of the second embodiment, a component equivalent to that of the first embodiment may have the same reference sign attached thereto, and the description thereof may be omitted or simplified.

<FIG> is a conceptual diagram showing a schematic configuration of the assisted circulation (V-A ECMO) pertaining to the second embodiment of the present invention. The dotted lines shown in <FIG> simplify and denote electric cables connecting sensors and a monitoring apparatus <NUM>.

<FIG> is a conceptual diagram showing an overview of blood circulation of a patient having the assisted circulation (V-A ECMO) applied thereto.

In <FIG>, a reference sign <NUM> represents an assisted circulation system (V-A ECMO).

The second embodiment is an example in which as shown in <FIG>, a patient (living body) P is connected with, for example, the assisted circulation system (V-A ECMO) <NUM> and a ventilator <NUM>.

In the second embodiment, the patient (living body) P is connected with, for example, the monitoring apparatus <NUM>, the assisted circulation system (V-A ECMO) <NUM>, an LCD touch panel <NUM>, the ventilator <NUM>, and a pulse oximeter (blood oxygenation index-measuring device) <NUM>.

The assisted circulation system (V-A ECMO) <NUM> differs from the assisted circulation system (V-V ECMO) <NUM> in the following points. The others are equivalent to the first embodiment, so the same reference signs are attached thereto and the descriptions thereof are omitted.

That is, as shown in <FIG>, the assisted circulation system (V-A ECMO) <NUM> differs therefrom in that blood removed from a vein V1 of the patient (living body, human body) P is circulated by a centrifugal pump (blood transfer pump) <NUM>, and blood after gas exchange of blood is performed in a membrane lung <NUM> is returned to an artery A1 of the patient P.

Specifically, a second return line 113B is connected to the artery A1 and is configured such that blood sent out from the membrane lung <NUM> is transferred (returned) from a return point P2 to the artery A1 through the second return line 113B.

Although the configurations of the monitoring apparatus <NUM> and the LCD touch panel <NUM> can be arbitrarily set, in the second embodiment, the monitoring apparatus <NUM> and the LCD touch panel <NUM> have the same configurations as in the first embodiment.

The connections and operations of the monitoring apparatus <NUM> and the LCD touch panel <NUM> are the same as in the first embodiment, so the same reference signs are attached thereto and the descriptions thereof are omitted.

In the present embodiment, of the configuration of the assisted circulation system <NUM>, a flow sensor <NUM>, an oxygen saturation sensor <NUM>, a blood transfer auto clamp <NUM>, a recirculation clamp <NUM>, and the membrane lung <NUM> configure an assisted circulation apparatus <NUM>. In other words, the assisted circulation system <NUM> includes the assisted circulation apparatus <NUM>, a blood removal line <NUM>, a blood transfer line <NUM>, a blood return line <NUM>, a recirculation line <NUM>, and the centrifugal pump <NUM>, and the components <NUM>, <NUM>, <NUM>, <NUM> and <NUM> can be handled as disposable products.

It is sufficient that the minimum configuration of the assisted circulation apparatus <NUM> includes the flow sensor <NUM>, the oxygen saturation sensor <NUM>, the blood transfer auto clamp <NUM>, the recirculation clamp <NUM>, and the membrane lung <NUM>, and the assisted circulation apparatus <NUM> may be configured to include other components (for example, part of the above lines). The assisted circulation apparatus <NUM> may further include a drive unit 115A that drives the centrifugal pump <NUM>. The assisted circulation apparatus <NUM> may further include the monitoring apparatus <NUM>.

Next, the blood circulation when applying the assisted circulation system (V-A ECMO) is described with reference to <FIG>.

In the patient (living body) P having the assisted circulation system (V-A ECMO) <NUM> applied thereto, as shown in <FIG>, blood oxygenated in the native lung (NL) and having an oxygen content (oxygen content parameter) CaO<NUM> (NL), an oxygen saturation degree (blood-oxygenated state index) SaO<NUM> (NL), and a flow rate (cardiac output) Qco is sent out by the heart to the artery A1.

On the other hand, in the assisted circulation (V-A ECMO), as shown in <FIG>, blood gas-exchanged and oxygenated by the membrane lung (ML) <NUM> and having an oxygen content (oxygen content parameter) CaO<NUM> (ML), an oxygen saturation degree (blood-oxygenated state index) SaO<NUM> (ML), and a flow rate (cardiac output) QECMO is sent out toward the artery A1 and joins blood sent out from the heart at the return point P2.

The blood joined at the return point P2 is mixed to become blood having an oxygen content CaO<NUM>, an oxygen saturation degree SaO<NUM>, and a flow rate QCIR (= Qco + QFCMO) and flows through the artery A1 to living tissue PS.

In the blood flowed to the living tissue PS and having the oxygen content CaO<NUM>, the oxygen saturation degree SaO<NUM>, and the flow rate QCIR, oxygen thereof is consumed by metabolism in the living tissue PS, carbon dioxide is generated, and the oxygen content and the oxygen saturation degree thereof decrease to an oxygen content CvO<NUM> and an oxygen saturation degree SvO<NUM>.

The blood having the flow rate QCIR and decreased to the oxygen content CvO<NUM> and the oxygen saturation degree SvO<NUM> flows through the vein V1 toward the heart and the native lung (NL).

In the blood flowing through the vein V1 toward the heart and the native lung (NL) and having the oxygen content CvO<NUM>, the oxygen saturation degree SvO<NUM>, and the flow rate QCIR, blood with the flow rate QECMO is removed at a blood removal point P1 and flows to the membrane lung (ML) of the assisted circulation system (V-A ECMO) <NUM>.

The blood removed and sent to the membrane lung (ML) is oxygenated by gas-exchanging the carbon dioxide (CO<NUM>) with the oxygen (O<NUM>) in the membrane lung (ML) and returns to the artery A1 at the return point P2.

On the other hand, the blood with the flow rate Qco (= QCIR-QECMO) that has not removed at the blood removal point P1 flows directly toward the heart through the vein V1.

The blood is oxygenated in the native lung (NL), becomes blood having the oxygen content CaO<NUM> (NL), the oxygen saturation degree SaO<NUM> (NL), and the flow rate (cardiac output) Qco, and is sent out to the artery A1.

In the blood circulation shown in <FIG>, blood is oxygenated by [DaO<NUM>-DvO<NUM>] shown in above Formula (<NUM>) in the membrane lung (ML) and the native lung (NL).

The blood circulation in the assisted circulation (V-A ECMO) can be described by focusing on either the assisted circulation flow rate QECMO or the arterial blood oxygen content CaO<NUM>.

When focusing on the assisted circulation flow rate QECMO, in the blood circulation in the assisted circulation (V-A ECMO), Formula (<NUM>) to Formula (<NUM>) hold, which are described in the assisted circulation (V-V ECMO) pertaining to the first embodiment. The content thereof is the same as the first embodiment, so the description thereof is omitted.

When assuming that blood flowing through the artery A1 to the living tissue PS has an arterial blood oxygen content CaO<NUM> and a circulating blood flow rate QCIR, an arterial blood oxygen transfer rate DaO<NUM> can be expressed by following Formula (<NUM>). [Expression <NUM>] <MAT>.

When applying the assisted circulation (V-A ECMO), the circulating blood flow rate QCIR is equal to the sum of the assisted circulation flow rate QECMO and the cardiac output Qco, so the circulating blood flow rate QCIR can be expressed by following Formula (<NUM>). [Expression <NUM>] <MAT>.

On the other hand, since the mass of the oxygen is conserved, the arterial blood oxygen content CaO<NUM> can be expressed as following Formula (<NUM>) by using the oxygen content CaO<NUM> (NL) after gas exchange in the native lung (NL), the circulating blood flow rate QCIR, the oxygen content CaO<NUM> (ML) after gas exchange in the membrane lung (ML), and the flow rate QECMO of blood oxygenated in the membrane lung (ML). [Expression <NUM>] <MAT>.

Since the carbon dioxide total emission amount V'CO<NUM> of the whole living body is equal to the sum of the carbon dioxide emission amount V'CO<NUM> (ML) of the membrane lung (ML) and the carbon dioxide emission amount V'CO<NUM> (NL) of the native lung (NL), Formula (<NUM>) is substituted for Formula (<NUM>), the left side of the resulting formula is divided by the carbon dioxide total emission amount V'CO<NUM> of the whole living body, the right side thereof is divided by the sum of the carbon dioxide emission amount V'CO<NUM> (NL) of the native lung (NL) and the carbon dioxide emission amount V'CO<NUM> (ML) of the membrane lung (ML), and the result is expressed by following Formula (<NUM>). [Expression <NUM>] <MAT>.

Since it is difficult to directly measure the cardiac output Qco in above Formulas (<NUM>) to (<NUM>), a general estimate of the carbon dioxide emission amount V'CO<NUM> (ML) in the membrane lung (ML) is appropriately used.

The calculation results of above Formulas (<NUM>) to (<NUM>) may be selectively displayed by operating the third touch portion 189C, for example.

The present invention is not limited to the above embodiments, and various modifications can be adopted within the scope of the present invention.

For example, in the above embodiments, the case of applying the monitoring apparatus <NUM> to the monitoring of the assisted circulation system (V-V ECMO) <NUM> and the assisted circulation system (V-A ECMO) <NUM> is described, but the monitoring apparatus <NUM> may be applied to, for example, the monitoring of an assisted circulation (V-V-A ECMO).

In the above embodiments, the case of using the ventilator <NUM> together with the assisted circulation system <NUM> or <NUM> is described, but it is possible to arbitrarily determine whether or not the ventilator <NUM> is used, and the carbon dioxide emission amount and the oxygen uptake amount may be calculated by the inspiratory gas and the expiratory gas when breathing using an oxygen mask or the like instead of the ventilator <NUM>.

In the above embodiments, the case is described where the gas sensor used for obtaining the gas exchange index at the time of calculating the contribution degree of the membrane lung <NUM> in the assisted circulation system (circuit) <NUM> is the carbon dioxide concentration sensor connected to the membrane lung <NUM> and the ventilator <NUM>, but for example, an oxygen concentration sensor connected to the membrane lung <NUM> and the ventilator <NUM> may be applied thereto, and the assisted circulation ratio may be calculated. The assisted circulation ratio may be calculated using both of the carbon dioxide concentration sensor and the oxygen concentration sensor.

The configurations and arrangement positions of the membrane lung inspiratory gas sensor <NUM>, the membrane lung expiratory gas sensor <NUM>, the ventilator inspiratory gas sensor <NUM>, and the ventilator expiratory gas sensor <NUM> can be arbitrarily set.

For example, the membrane lung inspiratory line <NUM> and the membrane lung expiratory line <NUM> may be provided with a sampling circuit (not shown), and one gas sensor may be used both as the ventilator inspiratory gas sensor <NUM> and the ventilator expiratory gas sensor <NUM>.

In the above embodiments, the case is described where the gas exchange index corresponding to the oxygen uptake amount is calculated by the gas-exchanged carbon dioxide concentration obtained by the membrane lung inspiratory gas sensor <NUM>, the membrane lung expiratory gas sensor <NUM>, the ventilator inspiratory gas sensor <NUM>, and the ventilator expiratory gas sensor <NUM>, but a configuration may be adopted where the gas exchange index is calculated by, for example, measuring the content of other gas (for example, anesthesia gas or the like) contained in respiratory gas, which can determine the content of carbon dioxide or oxygen.

In the above embodiments, the case where the monitoring apparatus <NUM> calculates the carbon dioxide emission amount in the native lung (NL) by the volume capno analysis is described, but a configuration may be adopted where the carbon dioxide emission amount in native lung (NL) calculated by the volume capno analysis is input from the outside.

For example, in the above embodiments, the case where the blood transfer pump is the centrifugal pump <NUM> is described, but instead of the centrifugal pump <NUM>, for example, a roller pump may be used in which a rotating roller rotates and squeezes a flexible tube to aspirate and deliver blood.

In the above embodiments, the various calculations in the monitoring apparatus <NUM> are described using mathematical formulas, but the above mathematical formulas are an example, it is not limited to the above mathematical formulas, and other formulas and calculation methods may be used.

In the above embodiments, an example of a schematic configuration of a flowchart for showing the operation of the monitoring apparatus <NUM> is described, but a method (algorithm) other than the above flowchart may be used for control.

In the above embodiments, the case of applying the monitoring apparatus <NUM> to the monitoring of the assisted circulation of the patient (human body, living body) P is described, but it may be applied to the assisted circulation of animals (living body) or the like.

Either one or both of the first calculation unit <NUM> and the second calculation unit <NUM> described in the first and second embodiments above may correspond to the "calculation unit" in the present invention.

On the other hand, as described above, the monitoring apparatus <NUM> of the first and second embodiments includes the first signal reception unit <NUM> to the sixth signal reception unit <NUM>, the first calculation unit <NUM>, the second calculation unit <NUM>, and the first storage unit <NUM>, but it is not limited thereto, and the monitoring apparatus <NUM> may include at least the assisted circulation ratio calculation unit <NUM>. In this case, the assisted circulation ratio calculation unit <NUM> corresponds to the "calculation unit" in the present invention.

Claim 1:
A monitoring apparatus (<NUM>) for being applied to an assisted circulation apparatus (<NUM>, <NUM>), the assisted circulation apparatus (<NUM>, <NUM>) for being connected to a living body (P), transferring blood removed from the living body to a membrane lung (<NUM>) by a blood transfer pump (<NUM>), and gas-exchanging and oxygenating the blood in the membrane lung in parallel with a native lung (NL), the monitoring apparatus (<NUM>) for monitoring an oxygenation state of blood in the living body (P), the monitoring apparatus (<NUM>) comprising:
an assisted circulation ratio calculation unit (<NUM>) configured to:
calculate a ratio of a first blood-oxygenated state index to a sum of the first blood-oxygenated state index and a second blood-oxygenated state index based on the first blood-oxygenated state index indicating an oxygenation state of blood by the membrane lung (<NUM>) and the second blood-oxygenated state index indicating an oxygenation state of blood by the native lung (NL), the ratio expressing a contribution degree of the assisted circulation apparatus (<NUM>, <NUM>) to the living body (P),
characterized in that the assisted circulation ratio calculation unit (<NUM>) is configured to compare the sum of the first blood-oxygenated state index and the second blood-oxygenated state index with a blood-oxygenated state index indicating an oxygenation state of blood based on metabolism estimated from a weight of the living body (P).