JPS6361026B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a carbon dioxide regulator for an exhalation circuit, which mixes a part of carbon dioxide generated during exhalation during artificial respiration with fresh gas such as oxygen or anesthetic gas air, and uses the mixture for inspiration. First, a conventional breathing circuit will be explained.
Various types of ventilator breathing circuits have been used in the past, including non-rebreathing ventilators, which are mainly used in hospital rooms, and circulation ventilators, which are used for anesthesia. Let's talk about. An example of a conventional non-rebreathing ventilator will be explained with reference to the circuit diagram shown in FIG. FIG. 1a shows the state at the start of inhalation, and FIG. 1b shows the state at the start of exhalation. In these figures, 1 is a bellows (or breathing bag) that stores fresh gas for intake, 2 is a fresh gas supply port such as oxygen, 2' is an air intake port, 3 is an exhaust valve for excess gas, and 4 is a communication port. tube, 5 is a Y-shaped tube,
One end thereof is connected to one end of an inhalation pipe 6 and an exhalation pipe 7, respectively, and the other end forms an air supply port 8. The other ends of the inhalation pipe 6 and the exhalation pipe 7 are connected to an inhalation valve 9 and an exhalation valve 10, respectively, which allow or cut off gas flow by switching. Reference numeral 11 represents an exhaust pipe connected to the exhalation valve 10 and discharges exhaled air, and 12 represents an alveolus. Note that although the intake valve 9 and the exhalation valve 10 are shown as valves that move for convenience of explanation, these may be check valves (one-way valves). Next, the operation will be explained. During intake, after opening the intake valve 9 and closing the exhalation valve 10 as shown in FIG. , intake pipe 6, Y-shaped pipe 5,
It is sent to the alveoli 12 via the exhaust port 8. During exhalation, if the exhalation valve 9 is closed and the exhalation valve 10 is opened as shown in FIG. It is discharged from 11. Note that during this time, the exhalation valve 9 is closed, so the first
By stretching in the direction of the arrow in FIG. b, fresh gas is sucked in from the fresh gas supply port 2, stored in the bellows 1, and prepared for the next intake. Artificial respiration is performed by repeating these actions. However, in conventional non-rebreathing ventilators, fresh gas for inspiration passes through the inspiratory tube 6 and into the alveoli 1.
By passing the exhalation air from the exhalation pipe 7, it was determined that the route and flow direction of the exhaled air was one-way. All of the carbon dioxide produced during exhalation is exhausted to the outside and is not reused, so there is no supply of carbon dioxide to the alveoli 12. Therefore, in patients with decreased lung function, blood In order to increase the concentration of oxygen inside, and to ensure safety during surgery, it is necessary to inhale excess oxygen, so it is used as a superexchanger.
It was inevitable that the partial pressure of carbon dioxide in the blood would become low, leading to an unfavorable state. Another disadvantage is that a large amount of fresh gas must be supplied since all exhaled air is exhausted to the outside. Next, an example of a conventional circulation type respirator for anesthesia will be explained with reference to the circuit diagram shown in FIG. This artificial respirator uses a mixed gas of anesthetic gas and oxygen, and FIG. 2a shows the state at the start of exhalation, and FIG. 2b shows the state at the start of exhalation. In these figures, the same reference numerals as in FIG. 1 indicate the same parts, and 13 is a carbon dioxide absorber, the interior of which is filled with a carbon dioxide absorbent 14 such as soda lime. Reference numeral 15 denotes a Y-shaped communication pipe, which is composed of a communication pipe 16, an exhalation pipe 17, and an exhalation pipe 18. One end of the communication pipe 16 is connected to the bellows 1, and the other end is branched into two directions, one of which is connected to the intake pipe 17. Natsute carbon dioxide absorber 1
3, the other end becomes an exhalation pipe 18 and is connected to the exhalation valve 10. Note that in this example as well, the exhalation valve 9 and the exhalation valve 10 may be check valves. The operation during inhalation is almost the same as that shown in Fig. 1a, except that the flow of expiration transfers the carbon dioxide in the exhaled gas stored in the communication pipe 16 and bellows 1 to the carbon dioxide absorbent in the carbon dioxide absorber 13. It is absorbed into the alveoli 14, removed, and then sent to the alveoli 12. During exhalation, the inhalation valve 9 is closed and the exhalation valve 10 is opened, and the exhaled air in the alveoli 12 is expelled by the suction force of the bellows 1 and the expiratory movement of the chest. Expired gas is stored in the communication tube 16 and bellows 1 from the alveoli 12 through the air supply port 8, the Y-shaped tube 5, the exhalation tube 7, the exhalation valve 10, and the exhalation tube 18 of the Y-shaped communication tube 15. Artificial respiration is performed by repeating these actions. However, even in conventional circulation-type anesthesia ventilators, carbon dioxide generated during exhalation is absorbed by the carbon dioxide absorbent 14 and is not supplied to the alveoli 12, which is undesirable as described above. As a result, there was also a drawback that a large amount of the carbon dioxide absorbent 14 was used in order to absorb most of the carbon dioxide gas in exhaled breath. Therefore, in an attempt to solve this problem, we have created a dead space in which the carbon dioxide contained in exhaled air is retained and used again for inhalation, and we have also created a rebreathing system in which exhaled air and exhaled air are passed through a single tube. Use a valve that directs the flow of gas in the circuit so that a portion of the gas flows back and forth, or use one without a carbon dioxide removal device,
Attempts have been made to directly add carbon dioxide gas to the intake air, but good results have not been obtained due to the complexity of the equipment, inconvenience of handling, and reduced efficiency in the use of fresh gas. This invention was made in order to eliminate the above-mentioned drawbacks, and by inhaling a part of carbon dioxide contained in exhaled air into the alveoli, it is possible to easily adjust the carbon dioxide concentration in the alveoli and blood. The present invention provides a carbon dioxide gas regulator for a breathing circuit. FIG. 3 is a circuit diagram showing an embodiment of this invention.
This corresponds to the breathing circuit shown in FIG. Figures 3a to 3c show inhalation, and Figure 3d shows exhalation. In these figures, the same reference numerals as in FIG. 1 indicate the same parts, and 21 is a Y-shaped communicating pipe;
3. Consists of an intake pipe 24. One end of the communication pipe 22 is connected to the bellows 1, and the other end is branched into two directions, forming an intake pipe 23, one of which serves as an intake valve 9, and the other serves as an exhalation pipe 24, which serves as a switching valve 2 for directing the flow of gas.
5. Next, the operation will be explained. The operation at the time of inhalation is as shown in FIG. By compressing in the direction of the arrow, the fresh gas stored in the bellows 1 passes through the communication pipe 22, intake pipe 23, exhalation valve 9, intake pipe 6, Y-shaped pipe 5, and air supply port 8 to the alveoli 12. Sent. next,
When the bellows 1 is compressed to a predetermined level, the intake valve is closed as shown in FIG. Compress 1. When the expiratory gas remaining in the expiratory tube 7 is sent to the alveoli 12 through the air supply port 8, the state shown in FIG. 3c is reached and the inhalation ends. Next, since exhalation occurs spontaneously, the inhalation valve 9 is kept closed as shown in FIG. Then, exhaled gas is discharged from the alveoli 12 to the outside through the exhaust pipe 11 via the air supply port 8, the Y-tube 5, the exhalation pipe 7, and the switching valve 25. Then, while exhaling, the bellows 1 is stretched in the direction of the arrow to introduce fresh gas from the fresh gas supply port 2, and if insufficient, air is introduced from the air suction port 2' and stored in the bellows 1. After expiration, the exhalation valve 25 is operated again to block the exhalation pipes 7 and 24, and the state returns to the state shown in FIG. 3a. Artificial respiration is performed by repeating this action. FIG. 4 is a circuit diagram showing another embodiment of the present invention, which corresponds to the breathing circuit shown in FIG. 2 when applied to a circulation type respirator for anesthesia. Figure 4 a-c
Figure 4d shows the action of inhalation and exhalation. In these figures, the same symbols as in Fig. 2 indicate the same parts,
26 is a Y-shaped communication pipe, which includes a communication pipe 16, an intake pipe 17,
It consists of an exhalation pipe 18, and the differences from Fig. 2 are as follows.
A switching valve 27 is provided at a point where one end of the communication pipe 16 branches into an intake pipe 17 and an exhalation pipe 18. Reference numeral 28 denotes a connecting portion where one end of the exhalation pipe 18 of the Y-shaped communication pipe 26 and one end of the exhalation pipe 7 are directly connected. In this case, the exhalation valve 9 may be removed, or a check valve or a solenoid valve may be used. Next, the operation will be explained. The operation of the intake pipe is as shown in FIG.
6 After communicating the intake pipe 17, when the bellows 1 is compressed, the exhaled gas stored in the bellows 1 during expiration passes through the communication pipe 16, the switching valve 27, and the intake valve 17, and then is discharged as shown in Fig. 2a. Sent to alveoli 12. Next, when the bellows 1 is compressed to a predetermined point, the switching valve 27 is switched to shut off the intake pipe 17 as shown in FIG. 4b, and the communication pipe 16 and exhalation pipe 18 are
After communicating with each other, the bellows 1 is further compressed. Then, the expiratory gas remaining in the expiratory tubes 7, 18 and the bellows 1 is sent to the alveoli 12, and the inhalation ends in the state shown in FIG. 4c. Next, during exhalation, as shown in FIG. 4d, when the bellows 1 is stretched with the switching valve 27 left as it is, the exhaled gas from the alveoli 12 flows through the air supply port 8, the Y-shaped tube 5, and the exhalation tube 7. , 18, the switching valve 27, and the communication pipe 16, and are stored in the bellows 1. The excess gas is then discharged to the outside through the exhaust valve 3. After expiration, the patient returns to the state shown in FIG. 4a and performs an inhalation operation, and this operation is repeated to perform artificial respiration. In the embodiment shown in FIG. 4, fresh gas containing exhaled gas is not stored in the bellows 1, but carbon dioxide is absorbed by the carbon dioxide suction device 13 and the stored exhaled gas is converted into fresh gas. Similarly, the fresh gas is sent to the alveoli 12 together with the fresh gas from the fresh gas supply port 2. FIG. 5 is a circuit diagram showing still another embodiment of the present invention, which is applied to a rebreathing type breathing circuit that can be used for either hospital rooms or anesthesia. Fifth
Figures a to c show the action of inhalation, and Figure 5d shows the action of exhalation.
In these figures, the same reference numerals as above indicate the same parts, and 29 is a storage bag that intermittently supplies fresh gas, which expands when filled with fresh gas and contracts when fresh gas is released, and is a rubber bag or bellows bag. etc. are used. Next, the operation will be explained. The operation during intake is as shown in FIG. 5a. When the intake valve 9 is opened, the fresh gas in the storage bag 29 is released and the storage bag 29 contracts, resulting in the state shown in FIG. 5b. Next, when the inhalation valve 9 is closed and the bellows 1 is compressed, the exhaled gas stored in the bellows 1, the communication pipe 16, and the exhalation pipe 7 is sent to the alveoli 12, resulting in the state shown in Fig. 5c. Finish inhaling. Next, during inspiration, when the bellows 1 is stretched as shown in FIG. 5b, exhaled gas from the alveoli 12 is stored in the bellows 1 in the same manner as described above. In addition, as shown in FIGS. 5 c to d, the intake valve 9
When closed, the storage bag 29 side, bellows 1 and alveoli 1
2 is pressure-blocked, fresh gas is supplied into the storage bag 29, expands, and becomes stored, waiting for the next intake operation. Artificial respiration is then performed by repeating these actions. FIG. 6 shows an example in which a mushy room valve and a solenoid valve are used in place of the switching valve 25 in the non-rebreathing type respirator shown in FIG. In this figure, reference numeral 30 denotes a mushy room valve, 31 a conduit tube branched from one end of the exhalation pipe 24, and 32 a bag made of rubber or the like attached to the end of the conduit tube 31 for introducing and discharging gas. It expands and contracts due to 33 is provided in the storage chamber exhalation pipe 24 that accommodates the bag 32, and has an exhaust port 34 at its upper part. 35 is a solenoid valve attached to the exhalation pipe 24. Next, the operation of this pine room valve 30 is
This will be explained with reference to Figures a to d. First, FIG. 6a shows a case where the operation during intake according to FIG. 3a is performed. Solenoid valve 3
5 and then compress the bellows 1 to open the exhalation pipe 24.
The retained gas becomes high pressure, passes through the conduit pipe 31, and is stored in the bag 32. Here, the bag 32 expands and expands to the full extent inside the storage chamber 33, and the exhaust port 3
Seal 4. In this case, the pressure of the gas remaining on the expiratory pipe 7 side is reduced by the compression of the bellows 1, which sends fresh gas through the inhalation pipe 6 and Y-shaped tube 5 to the alveoli 12. The pressure is lower than that on the 24 side. Therefore, the bag 32 can remain in an inflated state. Next, FIG. 6b shows the case where the intake operation according to FIGS. 3b and 3c is performed, and the solenoid valve 3
5 is opened, and the pressure of the gas compressed by the bellows 1 goes to the alveoli 12, and a part of the gas passes through the conduit 31 and presses inside the bag 32. FIG. 6e shows a case where the exhalation operation shown in FIG. 3d is being performed, and the solenoid valve 35 is closed. In this case, the gas on the expiratory pipe 7 side becomes high pressure due to exhalation from the alveoli 12, and the gas on the expiratory pipe 24 side becomes low pressure because the bellows 1 are stretched. Therefore, the gas in the bag 32 is discharged into the exhalation pipe 24 through the conduit pipe 31 by the suction force. Accordingly, the bag 32 is deflated and the exhaust port 34 is opened, and the exhaled gas in the exhalation pipe 7 is discharged to the outside through the exhaust port 34. In this way, by using the mushy room valve 30, exhaled gas can be automatically exhausted simply by switching the opening and closing of the solenoid valve 35. FIG. 7 shows another embodiment using a mushy room valve 30 and a solenoid valve 35, which is applied to the non-rebreathing type shown in FIG. 3. In this embodiment, a check valve 35' is located at the position of the solenoid valve 35 in FIG. 6, and the solenoid valve 35 is provided at the connection point between the intake pipe 6 and the exhalation pipe 7 (on the bellows 1 side). Since the pine room valve 30 usually has a check valve 35' integrated therein, it is practical to construct it as shown in FIG. FIG. 8 shows the breathing circuit (Japanese Unexamined Patent Application Publication No. 1983-1995) that was previously proposed for each of the respirators shown in FIGS.
150893)). In FIG. 8, reference numeral 36 denotes an outer tube, for example, a flexible plastic tube that is easily bent. 37 is a fresh gas supply pipe, which is also a flexible straight pipe made of vinyl chloride, for example. An air supply port 38 is attached to one end of the outer tube 36. One end of the fresh gas supply pipe 37 is located near the inside of the air supply port 38. 39 is a base body, which includes an outer pipe attachment part 40 and a fresh gas supply pipe attachment part 4.
1. It has an outer pipe communication hole 42 and a fresh gas supply pipe communication hole 43, and an outer pipe connection part 44 is fixed to the other end of the outer pipe 36, and the outer pipe at the other end of the outer pipe 36 The other ends of the connection part 44 and the fresh gas supply pipe 37 are connected to the outer pipe attachment part 40 and the fresh gas supply pipe attachment part 4, respectively.
It can be attached to 1. The attachment of the outer tube connection portion 44 of the outer tube 36 to the outer tube attachment portion 40 is configured to allow movement in the axial direction (in the direction of the arrow) and to prevent it from coming off during normal use. . For example, after the outer tube connecting portion 44 of the outer tube 36 is moved in the axial direction to determine its position, it is fixed from the outside with an appropriate band (not shown) to prevent further movement. be able to. 45
is a partition plate, which is integrally formed with the air supply port 38,
This is to restrict the movement of the end 37a of the fresh gas supply pipe 37 so that it does not protrude from the air supply port 38 during use and cause an unexpected accident. Note that the approach distance between this partition plate 45 and the front end 37a of the fresh gas supply pipe 37 is the same as that of the outer pipe attachment part 40.
By sliding the outer tube connecting portion 44 in the axial direction, adjustment can be made freely, and the gas 39 and the fresh gas supply tube 37 are configured so that they will not come off during use. Moreover, each part is assembled by fitting so that the whole can be disassembled. FIG. 9 shows an embodiment of a comprehensive circuit in which a non-rebreathing type, circulation type and rebreathing type respirator are integrated into one according to the present invention. It can be used in any of the breathing, circulation, and rebreathing methods. In this figure, the same reference numerals as above indicate the same parts, 46 is a respirator circuit, 47 is a breathing circuit, and 48, 49, 50 are switching valves. Also,
Reference numerals 51 and 51' indicate interlocking electromagnetic switching valves.
Further, symbols a, b, c, d, and e are connecting portions of communication pipes connected to each of the switching valves 48 to 50, and serve as gas communication ports. Each breathing method using this circuit is controlled by each switching valve 48 to 5.
It is determined by switching 0, and its operation is the same as each breathing method described above. Table 1 shows the gas conduction paths for each breathing method by combining the symbols of the connection parts a to e of the switching valves 48 to 50.

[Table] Figure 10 shows an embodiment in which a manually operated circulation type respirator is configured into one circuit in addition to the circulation type and rebreathing type respirator of the present invention. It can also be used in the following methods. In this figure, the same reference numerals as above indicate the same parts, and 52 is a breathing support bag. In this circuit, each breathing method is controlled by each electromagnetic switching valve 48, 50 and the interlocking switching valves 49, 4.
The operation is the same as each of the above-mentioned breathing methods, and artificial respiration by manual operation is performed by operating the breathing assistance bag 52. Second
The table shows the gas conduction paths in each breathing method by the combination of the symbols of the connection parts a to c of the switching valves 48 to 50.

[Table] In addition, the intake valve 9 and the switching valve 2 in the above embodiment
5, 27, 48 to 51, etc. are all constituted by electromagnetic valves, and if they are electrically controlled at the required timing, the required amount of carbon dioxide gas can be easily supplied.
Furthermore, in each of the above embodiments, a part of the exhaled air is sent just before the end of the inhalation, but a part of the exhaled air is sent at the beginning of the inhalation, or a part of the exhaled air is sent at other timings. Good too. The correspondence between the claims and the embodiment shown in FIG. 3 is as follows.

[Table] As explained in detail above, the present invention includes an inhalation means and an evacuation means that alternately perform an inhalation cycle of fresh gas from an inhalation pipe and an ejection cycle of intake gas containing carbon dioxide from an exhalation pipe. In the equipped breathing circuit, the exhaled gas containing carbon dioxide in the expiratory pipe is adjusted and the required amount is returned in the opposite direction to the expiration direction for re-inhalation. Necessary carbon dioxide gas can be supplied without the need for a carbon dioxide gas. In addition, since a portion of the exhaled gas in the exhalation pipe is reused, the amount of fresh gas used can be reduced, so it is extremely economical in terms of fresh gas supply.
Furthermore, since the fresh gas inhaled from the inhalation pipe is subsequently returned to the expiration pipe in the opposite direction to the exhalation direction of the exhaled gas and inhaled, there is an advantage that the fresh gas can be accurately controlled by adjusting the timing of returning the exhaled gas.

[Brief explanation of drawings]

Figures 1a and b are circuit diagrams showing a conventional non-rebreathing type respirator, Figures 2a and b are circuit diagrams showing a conventional circulation type respirator, and Figures 3a to d are circuit diagrams showing a conventional non-rebreathing type respirator. FIGS. 4a to 4d are circuit diagrams showing another embodiment of the present invention. FIGS. 5a to d are circuit diagrams showing still another embodiment of the present invention. FIG. 6a -c are explanatory diagrams showing an example in which a pine room valve is used in the embodiment shown in FIG. 3, FIG. 7 is a circuit diagram showing another example in which a pine room valve is similarly applied to the embodiment shown in FIG. 3, and FIG. Side sectional view of the breathing circuit proposed earlier,
FIG. 9 is a circuit diagram showing an embodiment in which the embodiments of FIGS. 3, 4, 5, and 8 are combined into one circuit, and FIG. FIG. 9 is a circuit diagram showing an embodiment in which a manually operated respirator is combined with the embodiments shown in FIGS. In the figure, 1 is bellows, 2 is fresh gas supply port, 2'
is an air intake port, 3 is an exhaust valve, 5 is a Y-shaped pipe, 6 is an intake pipe, 7 is an exhalation pipe, 8 is an air supply port, 9 is an intake valve, 1
1 is an exhaust pipe, 12 is an alveolus, 21 is a Y-shaped communication pipe, 2
The communication pipe 23 is an intake pipe, 24 is an exhalation pipe, and 25 is a switching valve.

Claims (1)

[Claims] 1. In a carbon dioxide gas regulator used in a breathing circuit equipped with an inhalation means and an evacuation means that alternately carry out an inhalation cycle of fresh gas from an inhalation pipe and an ejection cycle of exhaled gas containing carbon dioxide from an exhalation pipe, the above-mentioned inhalation means for regulating the re-inhalation amount of exhaled gas containing carbon dioxide in said expiratory tube during the cycle, and returning said adjusted exhaled gas in a direction opposite to said exhalation direction to interrupt said fresh gas inhalation and subsequently 1. A carbon dioxide gas regulator for a breathing circuit, comprising a means for re-inhaling carbon dioxide, and adjusting the amount of carbon dioxide gas re-inhaled independently of the amount of inhaled gas.