JP2001095921A - Method and system for anesthetization - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily practice in use anesthetization with a low flow rate. SOLUTION: From detected values by oxygen sensors 41a and 41b and carbon dioxide sensors 42a and 42b provided respectively in mixing chambers 26 and 28 in an expiration flow path 22 and an inspiration flow path 21 and a flow rate sensor 37 provided at least in one of the expiration flow path and the inspiration flow path, oxygen uptake and carbon dioxide output on every respiration of a patient during anesthetization are operated in an operating part 14 and incoming and outgoing balance of an anesthetic is operated from the detected values of anesthetic gas sensors 43a and 43b respectively provided in the mixing chambers 26 and 28 and a flow rate sensor 37 and these operated values are displayed on a displaying part 15 as a condition of metabolism of the patient in real time.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an anesthesia method and an anesthesia system capable of safely performing, for example, low flow anesthesia.

[0002]

2. Description of the Related Art Surgery can be performed safely at present largely due to advances in anesthesia technology. But,
Anesthesia systems that often seem to be almost complete still have major problems.

At present, the main anesthesia method in Japan is semi-closed anesthesia (high flow anesthesia), in which 5-8 liters of fresh air per minute supplied from the anesthesia machine main body as an anesthesia gas supply means to the anesthesia circulation circuit. Most of the gas (anesthetic gas) was discarded outside the anesthetic circulation circuit without being ingested by the patient. In addition, the operating staff in the operating room often inhales the discarded anesthetic gas, which often hinders the operation.

[0004] In recent years, the so-called excess anesthesia gas elimination device that collects and discharges excess anesthesia gas to the outside of the hospital has become widespread. A new problem has been pointed out that laughter gas and Freon-based anesthetic gas (isoflurane, halolan, etc.) contained in the anesthetic gas discharged into the atmosphere may destroy the ozone layer and cause global warming. ing.

[0005]

By the way, low-flow anesthesia for reducing the fresh gas supplied from the anesthesia machine body to 1 liter per minute or less is an extremely effective means for solving the above-mentioned problems. Even when trying to adopt this low-flow anesthesia in the conventional anesthesia system, the operation for maintaining appropriate ventilation conditions and anesthesia depth of the patient becomes very complicated compared to the case of using semi-closed anesthesia, and actually Was difficult to adopt. That is, in low-flow anesthesia, when the metabolism of the patient changes, excess or deficiency of the supplied oxygen is likely to occur, and it is necessary to take measures such as adjusting the ventilation volume to an appropriate value. Also, since the concentration of the anesthetic gas (volatile anesthetic) contained in the intake air of the anesthesia circulation circuit is different from the concentration set in the vaporizer of the anesthesia device main body, in order to maintain anesthesia at an appropriate depth, It is necessary to frequently change the setting of the flow meter and the setting of the concentration of the vaporizer, and the operation for that is very complicated.

Therefore, the present inventors have determined that it is essential to directly monitor the metabolism of a patient in order to achieve low flow anesthesia. That is, the metabolism of the patient changes every moment due to a gradual change in body temperature and other changes in the situation, but this changes the necessary amount of oxygen and also changes the amount of carbon dioxide emitted. Therefore, in order to supply oxygen adequately and to provide adequate ventilation, it is more convenient to accurately monitor and monitor changes in the patient's metabolism. is there.

By the way, in order to monitor the metabolic state of a patient, it is necessary to detect the oxygen intake and the carbon dioxide emission with high accuracy every moment. Conventionally, the oxygen concentration and the carbon dioxide concentration in the expiratory flow path and the inspiratory flow path of the anesthesia circuit have been respectively detected.However, this type of conventional detection method is, for example, in the middle of the inspiratory flow path. A method of providing a large-volume mixing chamber, averaging the oxygen and carbon dioxide gas concentrations in the breath, sampling the averaged breath in the chamber while aspirating with a pump, and detecting it with an infrared sensor or the like. However, the response was too slow to detect the oxygen concentration and carbon dioxide concentration in a very real time.

[0008] For the above reasons, low flow anesthesia is currently rarely implemented in Japan, although its advantages are clear. Further, low-flow anesthesia can be expected to be greatly reduced in terms of medical expenses since the amount of anesthetic gas used can be extremely reduced. The present invention has been made in view of the above circumstances, and could not be realized conventionally expected,
An object of the present invention is to provide an anesthesia method and an anesthesia system that can easily perform low-flow anesthesia.

[0009]

The present invention has the following features in order to solve the above-mentioned problems. That is,
The invention according to claim 1 provides an anesthesia machine main body that supplies at least a mixture of laughing gas, oxygen gas, and volatile anesthetic, and the laughing gas, oxygen gas, and volatile gas supplied from the anesthesia machine main body. A fresh gas containing an anesthetic is mixed into the circulating air after absorbing and removing carbon dioxide from the exhalation of the patient, and the circulating air and the fresh gas are mixed and sent to the patient as inhaled air. In an anesthesia method of sending an inhalation containing a volatile anesthetic to a patient from the anesthetic circulation circuit to anesthetize the patient, the mixing chamber provided in the expiration flow passage and the inspiration flow passage in the anesthesia circulation circuit, respectively. , Oxygen sensor,
A carbon dioxide gas sensor and an anesthetic gas sensor are provided, respectively, and a flow rate sensor is provided in a breathing circuit connecting the expiratory flow path and the inspiratory flow path to the patient.From the detection values of the oxygen sensor, the carbon dioxide gas sensor and the flow rate sensor, the The anesthesia circulation is calculated from the anesthesia machine main body based on the calculated values of oxygen intake and carbon dioxide emission for each breath, and anesthesia gas balance based on the values detected by the anesthesia gas sensor and the flow rate sensor. The patient is anesthetized by determining the amount of fresh gas to be supplied to the circuit, the component ratio, and the ventilation of the ventilator.

Further, the invention according to claim 2 provides an anesthesia machine main body for supplying at least a mixture of laughing gas, oxygen gas and volatile anesthetic, and the laughing gas supplied from the anesthesia machine main body. Fresh gas containing oxygen gas and volatile anesthetic
An anesthesia circuit that mixes the circulating gas and the fresh gas into the circulating air after absorbing and removing carbon dioxide from the exhalation of the patient and sends the mixed gas and the fresh gas to the patient as inhalation. In an anesthesia system for anesthetizing a patient by sending an inspiratory gas containing the same to a patient, mixing chambers are provided in an expiratory flow path and an inspiratory flow path in the anesthetic circulation circuit, and an oxygen sensor and a carbon dioxide gas sensor are provided in each of the mixing chambers. An anesthesia gas sensor is provided, and a flow sensor is provided in a breathing circuit connecting the expiratory flow path and the inspiratory flow path to the patient. An arithmetic unit for calculating the oxygen intake and the carbon dioxide emission is provided, and a display unit for displaying the value calculated by the arithmetic unit is provided.

According to the present invention, an oxygen sensor provided in each of the mixing chambers in the expiratory flow path and the inspiratory flow path,
From the detected value of the carbon dioxide sensor and the flow rate sensor provided in the breathing circuit, the oxygen uptake for each respiration of the patient under anesthesia and the carbon dioxide emission are calculated, and the expiratory flow path and the inspiratory flow path are calculated. The anesthetic agent balance is calculated from the values detected by the anesthesia gas sensor and the flow rate sensor provided in the mixing chamber, and based on the calculated values, the amount of fresh gas supplied from the anesthesia machine body to the anesthesia circulation circuit and its amount. The patient is anesthetized by determining the component ratio and the ventilation of the ventilator. In this way, the metabolic state of the patient is monitored in real time, and the amount of fresh gas supplied from the anesthesia machine main body to the anesthesia circuit and its component ratio are monitored while accurately grasping the necessary oxygen amount and anesthetic amount as needed. Thus, low-flow anesthesia, which could not be performed conventionally, has become possible.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of an entire anesthesia system showing an embodiment of the present invention. As shown in this figure, an anesthesia system 1 includes at least an anesthesia machine main body 2 for supplying a mixture of laughing gas, oxygen gas and volatile anesthetic, and a laughing gas supplied from the anesthesia machine main body 2. Fresh gas containing oxygen gas and a volatile anesthetic is mixed into the exhalation of the patient A, and the circulating air and the fresh gas are mixed and sent to the patient A as inspired air, and the mixture is largely divided into an anesthesia circulation circuit 3. The anesthesia machine main body 2 includes a gas supply unit 10 for supplying an anesthetic gas including a laughing gas, a flow meter 11 for measuring a flow rate of the anesthetic gas supplied from the gas supply unit 10, and a volatile anesthetic gas in the anesthetic gas. A vaporizer 12 for supplying the agent in a vaporized state.

The gas supply unit 10 controls the pressure of oxygen gas, laughing gas, and air supplied from the outside,
The pressure at that time is displayed. When the supply of the oxygen gas is insufficient, the supply of the laughing gas can be automatically stopped. As the flow meter 11, a conventionally used rotameter type flow meter may be used, but it is preferable to use an electronic flow meter using a mass flow meter from the viewpoint that accurate measurement is possible. Also,
Among them, those capable of measuring with high accuracy in a flow rate range of 2 liters per minute or less are more preferable so as to be compatible with low flow anesthesia.

The vaporizer 12 is a volatile anesthetic.
Halothane, enflurane, isoflurane, sevoflurane, and desflurane, which has recently been attracting attention, are sent to a vaporization chamber by a microinjection pump so as to have a predetermined concentration, and the volatile anesthetic vaporized here is supplied to the gas supply unit 10. Is mixed with the anesthetic gas sent from the company. In addition,
Here, the anesthesia machine main body 2 includes a pressure sensor 13, a calculation unit 14, and a display unit 15.
This will be described in detail later.

The anesthesia circulation circuit 3 mixes a fresh gas (anesthetic gas) containing a volatile anesthetic supplied from the anesthesia machine main body 2 into the circulating air after absorbing and removing carbon dioxide from the exhalation of the patient A. Then, the mixture of the mixed gas and the fresh gas is sent to the patient A as inhalation. The anesthesia circuit 3 includes an inspiratory flow path 21 into which inspired air supplied to the patient A flows.
And an exhalation flow path 22 into which exhalation from the patient A flows, and a respiratory circuit 23 connecting the patient A to the inspiration flow path 21 and the exhalation flow path 22. The breathing circuit 23 may have a coaxial double tube structure.

The intake channel 21 is provided with an intake valve 25 and a mixing chamber 26 in order from a side far from the patient A to a side closer to the patient A, and is provided on the opposite side of the side of the intake channel 21 connected to the patient A. The end on the side merges with the flow path 2 a to which the anesthetic gas is supplied from the anesthesia device main body 2 and is connected to the end of the expiration flow path 22.

The mixing chamber 26 does not mix all the gas in the flow path into the chamber as in the prior art and averages the gas concentration.
As disclosed in Japanese Patent Publication No. 148, a small amount of divergent flow that constantly changes at a constant ratio with the total flow rate of the respiratory air flowing in the flow path is mixed into the chamber through the bypass flow path,
It averages the concentration. As a result, the size can be reduced without losing the function of averaging the gas concentration, and the entire apparatus can be reduced in size without difficulty. In addition, a mixing chamber 28 on the exhalation side described later.
Has a similar structure.

The exhalation valve 25 permits the flow of gas from the carbon dioxide absorption canister 32 to the mixing chamber 26 side, but restricts the reverse flow. The exhalation flow path 22 includes a mixing chamber 28, an exhalation valve 29, a relief valve 30, a bag 31 and a carbon dioxide absorption canister 32, and an anesthetic absorption canister 33.
Are sequentially provided in a direction away from the patient A, and the carbon dioxide absorption canister 32 has an anesthetic absorption canister 3.
3 are juxtaposed.

The exhalation valve 29 is provided in the mixing chamber 28.
The flow of gas from the gas to the bag 31 is permitted, but the reverse flow is restricted. When the pressure in the expiratory flow path 22 becomes equal to or higher than a predetermined pressure, the relief valve 30
It releases the internal pressure and regulates the pressure from rising further. The bag 30 is a bag-shaped one that can be evacuated to send inhalation to the patient A, and has various sizes according to the supply amount of inhalation to be sent to the patient A, and can be replaced as appropriate. .

The carbon dioxide absorption canister 32 is
It absorbs and removes carbon dioxide from the exhaled air, and is filled with a carbon dioxide absorbent such as soda lime. In the case of low flow anesthesia, a large amount of carbon dioxide is used because the amount of absorbed carbon dioxide increases. The anesthetic absorption canister 33 absorbs and removes an excess anesthetic from the exhalation of the patient A, and thereby, even if the anesthesia becomes too deep, its concentration can be rapidly reduced. .

A three-way valve 35 is provided at a portion of the bag 30 connected to the exhalation flow path 22. The three-way valve 35 switches the expiration flow path 22 between the bag 30 and the ventilator 36. You can connect. Respirator 36
Can be selected from both a capacity limit type in which capacity is controlled and a pressure limit type in which pressure is controlled. The ventilator 36 is provided with an outlet (not shown) for discharging surplus gas.

The breathing circuit 23 is provided with a flow sensor 37. The flow rate sensor 37 measures the flow rates of the expiratory flow path and the inspiratory flow path, and the ventilation volume is determined based on the detected values. It is sufficient that the flow sensor 37 is provided in either the expiratory flow path or the inspiratory flow path, but as in this embodiment, it is provided in both the expiratory flow path and the inspiratory flow path.
If the average value is determined as the flow velocity, measurement with less error can be performed. The pressure sensor 13 is connected to the breathing circuit 23 so that the pressure of expiration and inspiration can be measured. This enables pressure correction when accurately determining the ventilation volume.

Further, oxygen sensors 41a, 41b,
Carbon dioxide sensors 42a, 42b, anesthetic gas sensor 43
a and 43b are provided respectively. These sensors are electrically connected to a calculation unit 14 provided in the anesthesia machine main body. The calculation unit 14 calculates the oxygen intake and the carbon dioxide emission for each respiration of the patient A under anesthesia based on the detection values from these sensors and the detection values from the flow rate sensors, and anesthesia gas sensors 43a and 43b. The anesthesia gas balance is calculated on the basis of the detected value of the above and the detected value from the flow rate sensor. Then, those operation values are calculated by the operation unit 1
The display unit 15 is connected to the display unit 15.

As the oxygen sensors 41a and 41b, there are a galvanic method, a porous membrane method, and the like. From the viewpoint of quick response, it is preferable to use a paramagnetic method. The carbon dioxide sensors 42a and 42b include:
It is preferable to use a polymer composite film type rather than an infrared absorption type from the viewpoint of a quick response as in the above.

Next, an anesthesia method using the above anesthesia system will be described. Oxygen gas, laughing gas and air are supplied to the gas supply unit 10 of the anesthesia machine body 2 from the outside,
Here, the pressure is adjusted. The flow rate of the anesthetic gas is measured by the flow meter 11, and it is determined whether or not the flow rate is a preset value. An anesthetic gas having a predetermined flow rate measured by a flow meter is mixed with a volatile anesthetic in the vaporizer 12 and is supplied to the flow path 2a.
Is supplied to the anesthesia circulation circuit 3 through Anesthesia circulation circuit 3
Then, a constant flow of circulating air is supplied to the patient A at a predetermined pressure by the bag 31 or the artificial respirator 36.

Specifically, the circulating air supplied from the bag 31 or the ventilator 36 absorbs and removes the carbon dioxide contained therein by the carbon dioxide gas canister 32, and at the same time, absorbs an anesthetic as needed. Excess anesthetic is absorbed and removed by the canister 33. Thereafter, an anesthetic gas containing a volatile anesthetic supplied from the anesthesia machine main body 2 is mixed into the circulating air.
5 and the mixing chamber 6, the breathing circuit 23
From which it is supplied to patient A in the form of inspiration. Further, the exhaled breath exhaled from the patient A reaches the exhalation flow path 22 from the breathing circuit 23 and returns to the bag 31 or the artificial respirator 36 again through the mixing chamber 28 and the intake valve 29. The above is a series of flows of circulating air, which repeatedly and continuously flow.

In the flow of exhalation or inspiration of the above anesthesia system, oxygen sensors 41a, 41b and carbon dioxide sensor 42a provided in mixing chambers 26, 28 interposed in the inhalation flow path 21 and the expiration flow path 22, respectively. ,
Based on the detection value of 42b and the detection value of the flow sensor 37 provided in the breathing circuit 23, the calculation unit 14 calculates the oxygen intake and the carbon dioxide emission for each respiration of the patient A under anesthesia. . For example, to obtain the oxygen intake, a difference (concentration difference) between the detection value of the oxygen sensor 41a on the inspiration side and the detection value of the oxygen sensor 41b on the expiration side is obtained, and the ventilation obtained from the detection value of the flow rate sensor 37 is obtained. It can be easily determined by multiplying the quantity. Note that the ventilation amount is subjected to pressure correction based on the detection value from the pressure sensor 13. The amount of carbon dioxide emission can be determined by a similar method.

Then, the oxygen intake and carbon dioxide emission for each respiration, which are indexes indicating the metabolic state of the patient A thus obtained, are displayed on the display unit 15 one by one. Further, one of the various characteristics indicating the metabolic state of the patient A is a respiratory quotient RQ. This refers to the ratio between carbon dioxide output and oxygen uptake, and the respiratory quotient RQ varies depending on the type of substance burned in the cell (metabolized substrate). For example, the respiratory quotient for glucose is 1.0, the respiratory quotient for lipids is about 0.7, and the respiratory quotient for proteins is about 0.8.
This respiratory quotient is also calculated by the calculation unit 14 and displayed by the display unit 15. It is known that the change in the respiratory quotient also changes the ventilation demand, and at this point, it is meaningful to display the respiratory quotient. Further, the difference between the detection values of the anesthesia gas sensors 43a and 43b provided in the mixing chambers 26 and 28 in the expiratory flow path and the inspiratory flow path,
The anesthetic gas balance can be obtained by multiplying the ventilation amount obtained from the detected value of. The balance value of the anesthetic gas is calculated by the calculation unit 14 and displayed on the display unit 15 for each breath.

As described above, various characteristics representing the metabolic state of the patient A, such as oxygen intake, carbon dioxide consumption, anesthesia gas balance, respiratory quotient, are displayed on the display unit 15 in real time for each breath. Therefore, the surgical staff views these values and determines the amount of the anesthetic gas supplied from the gas supply unit 10, the amount of the volatile anesthetic mixed in from the vaporizer 12, and the respirator 36. It is possible to adjust low ventilation anesthesia, which has not been widely used because the operation is conventionally complicated. Incidentally, the supply amount of the anesthetic gas supplied from the anesthesia machine main body to the anesthesia circulation circuit (this value is also the amount of anesthesia gas discharged simultaneously to the outside of the hospital) is conventionally 5 to 8 liters per minute. , To 1-2 liters per minute.

In the above-described embodiment, the oxygen sensors 41 provided in the mixing chambers 26 and 28, respectively.
a, 41b, detection values of the anesthetic gas sensors 43a, 43b of the carbon dioxide sensors 42a, 42b, and the respiratory circuit 23
The calculation unit 14 calculates the oxygen uptake, carbon dioxide emission, and anesthesia gas balance value for each respiration of the patient A under anesthesia from the detection value of the flow sensor 37 provided in It is displayed on the display unit. Based on the calculated values, the amount of anesthesia gas supplied from the gas supply unit 10, the amount of volatile anesthetic mixed therein, and the amount of ventilation by a ventilator etc. are automatically determined. In this case, it is expected that the complexity of performing low-flow anesthesia can be further reduced.

[0031]

As described above, according to the present invention, the detection values of the oxygen sensor and the carbon dioxide sensor provided in the mixing chambers in the expiratory flow path and the intake flow path, and the detection values of the expiratory flow path and the intake flow path, respectively. From the detected value of the flow sensor provided in at least one, the oxygen intake and the carbon dioxide emission for each respiration of the patient during anesthesia are calculated, and the metabolic state of the patient is monitored from the calculated values, and the mixing chamber is monitored. The anesthesia gas balance is calculated from the detection values of the anesthesia gas sensor and the like provided in the apparatus. As described above, since the metabolic state of the patient is directly monitored in real time, the necessary amount of oxygen and the like can be accurately grasped one by one. In addition, since the anesthetic gas storage balance can be grasped by calculation, the low flow anesthesia can be obtained. Became possible. In addition, the problem of destruction of the global environment, which has been a major problem in using the conventional anesthesia system, can be solved, and the medical expenses can be reduced.

[Brief description of the drawings]

FIG. 1 is a configuration diagram illustrating an entire anesthesia system according to an embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Anesthesia system 2 Anesthesia machine main body 3 Anesthesia circulation circuit 10 Gas supply part 11 Flow meter 12 Vaporizer 14 Operation part 15 Display part 21 Intake flow path 22 Expiration flow path 26 Mixing chamber 28 Mixing chamber 37 Flow rate sensor 41a, 41b Oxygen sensor 42a , 42b Carbon dioxide sensor 43a, 43b Anesthetic gas sensor

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[Procedure amendment]

[Submission Date] January 20, 2000 (2000.1.2
0)

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0018

[Correction method] Change

[Correction contents]

The intake valve 25 permits the flow of gas from the carbon dioxide absorption canister 32 to the mixing chamber 26, but restricts the reverse flow. The exhalation flow path 22 includes a mixing chamber 28, an exhalation valve 29, a relief valve 30, a bag 31 and a carbon dioxide absorption canister 32, and an anesthetic absorption canister 33.
Are sequentially provided in a direction away from the patient A, and the carbon dioxide absorption canister 32 has an anesthetic absorption canister 3.
3 are juxtaposed.

[Procedure amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0021

[Correction method] Change

[Correction contents]

A three-way valve 35 is provided at the connection portion of the bag 31 with the exhalation flow path 22. The three-way valve 35 switches the exhalation flow path 22 between the bag 30 and the ventilator 36. You can connect. Respirator 36
Can be selected from both a capacity limit type in which capacity is controlled and a pressure limit type in which pressure is controlled. The ventilator 36 is provided with an outlet (not shown) for discharging surplus gas.

[Procedure amendment 3]

[Document name to be amended] Statement

[Correction target item name] 0026

[Correction method] Change

[Correction contents]

Specifically, the circulating air supplied from the bag 31 or the ventilator 36 absorbs and removes the carbon dioxide contained therein by the carbon dioxide gas canister 32, and at the same time, absorbs an anesthetic as needed. Excess anesthetic is absorbed and removed by the canister 33. Thereafter, an anesthetic gas containing a volatile anesthetic supplied from the anesthesia machine main body 2 is mixed into the circulating air.
5 and mixing chamber 26 , breathing circuit 2
3, from which it is delivered to patient A in the form of inspiration. Further, breath discharged from the patient A, leads from the respiratory circuit 23 to the expiratory flow path 22, mixing chamber 28, expiratory
It is returned to the bag 31 or the ventilator 36 again via the valve 29. The above is a series of flows of circulating air, which repeatedly and continuously flow.

Claims (2)

[Claims] 1. An anesthesia machine main body which supplies at least a mixture of laughing gas, oxygen gas and volatile anesthetic, and said laughing gas, oxygen gas and volatile anesthetic supplied from said anesthetic machine main body. An anesthesia circuit for mixing the fresh gas containing gas into the circulating gas after absorbing and removing carbon dioxide from the exhalation of the patient, mixing the circulating gas with the fresh gas, and sending the mixed gas to the patient as inhalation; An anesthesia method for anesthetizing a patient by sending an inhalation containing a volatile anesthetic to a patient from a circulation circuit, wherein an oxygen sensor is provided in a mixing chamber provided in an expiration flow path and an inspiration flow path in the anesthesia circulation circuit, respectively. , A carbon dioxide gas sensor and an anesthetic gas sensor
A flow sensor is provided in a respiratory circuit connecting the expiratory flow path and the inspiratory flow path to a patient, and oxygen intake, carbon dioxide gas for each respiration of the patient during anesthesia, While calculating the discharge amount, the anesthesia gas balance is calculated from the detection values of the anesthesia gas sensor and the flow rate sensor, and the amount and components of fresh gas supplied from the anesthesia machine body to the anesthesia circulation circuit based on the calculated values. An anesthesia method, wherein a patient is anesthetized by determining a ratio and a ventilation volume of a respirator. 2. An anesthesia machine main body which supplies at least a mixture of laughing gas, oxygen gas and volatile anesthetic, and said laughing gas, oxygen gas and volatile anesthetic supplied from said anesthetic machine main body. An anesthesia circuit for mixing the fresh gas containing gas into the circulating gas after absorbing and removing carbon dioxide from the exhalation of the patient, mixing the circulating gas with the fresh gas, and sending the mixed gas to the patient as inhalation; In an anesthesia system for sending an inspiration containing an anesthetic gas from a circulation circuit to a patient to anesthetize the patient, a mixing chamber is provided in each of an expiration flow path and an inspiration flow path in the anesthesia circulation circuit, and each of the mixing chambers is provided. An oxygen sensor, a carbon dioxide gas sensor, and an anesthesia gas sensor; and a flow sensor in a breathing circuit connecting the expiratory flow path and the inspiratory flow path to a patient. A calculation unit for calculating the oxygen intake and carbon dioxide emission for each respiration of the patient under anesthesia from the detected values of the above, and a display unit for displaying the value calculated by the calculation unit is provided. Anesthesia system.