JPH0142217B2 - - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a breathing circuit conduit and a breathing circuit device using this conduit. Prior art and its problems A breathing circuit device is used to connect a patient to a respirator, anesthesia machine, etc. The conduits used in such a breathing circuit device are two flexible tubes with different diameters, one being an inner tube and the other being an outer tube, and both are arranged approximately coaxially. It is a double tube, with one side inside the inner tube and between the inner and outer tubes serving as a gas flow path for exhalation, and the other for inhalation. Conventionally, in order to prevent blockage due to collapse of the pipe, that is, kinking, and increase flexibility, such double pipes have conventionally used a flexible pipe with corrugated inner and outer walls as the outer pipe, and a corrugated pipe with a corrugated inner wall as the inner pipe. Either a serpentine pipe or a straight pipe with smooth inner and outer walls is used. However, with such conventional double pipes, (1) it is difficult to drain water accumulated within the circuit (particularly within the wall of the outer pipe); (2) Turbulent flow tends to occur in the outer pipe, which tends to increase pressure loss. (3) The tube stretches easily and has great compliance. (4) When the inner pipe is a straight pipe, the pipe is likely to be crushed when the circuit is bent. There are drawbacks such as. Purpose of the Invention The main purpose of the present invention is to facilitate drainage of stored water, reduce pressure loss due to turbulence,
Another object of the present invention is to provide a double-pipe breathing circuit conduit that has low compliance and is not easily crushed when bent, and a breathing circuit device. Such objects are achieved by the following first and second inventions. That is, the first invention consists of two flexible tubes each having different diameters, one of which is an inner tube and the other an outer tube, forming a double tube, and the inner tube and between the inner tube and the outer tube. In a breathing circuit conduit with a gas flow path, at least the outer wall of the inner tube and the outer tube has irregularities, the inner wall of the outer tube has a substantially smooth surface, and the inner tube has an uneven surface. This conduit for a breathing circuit is characterized in that there is no continuous hollow portion extending in the longitudinal direction of the tube within at least one wall of the outer tube. In addition, preferred embodiments include the following. (i) In the first invention, the inner tube consists of an outer wall having an uneven surface and an inner wall having a substantially smooth surface. (ii) In the first invention or (i) above, the value obtained by dividing the difference in unevenness of the outer wall having unevenness by the minimum diameter of the inner wall is 0.01 to 0.13. (iii) In the first invention or (i) or (ii) above, the value obtained by dividing the difference in unevenness of the inner wall consisting of a substantially smooth surface by the minimum diameter of the inner wall is 0.07 or less. (iv) In the first invention or (i) to (iii) above, the value obtained by dividing the pitch of the convex portions of the uneven outer wall by the minimum diameter of the inner wall is 0.1 to 0.6. (v) In the first invention or (i) to (iv) above, the difference in the unevenness of the outer wall of the inner tube is 80% or less of the difference in unevenness of the outer wall of the outer tube. (vi) In the first invention or (i) to (v) above, the interior of the inner tube is an inhalation flow path, and the space between the inner tube and the outer tube is an exhalation flow path. (vii) In the first invention or (i) to (vi) above, when the double tube is extended, the inner tube and the outer tube are arranged substantially coaxially. Further, a second invention provides a double pipe in which one of the inner pipes is made up of two flexible pipes having different diameters, an expiratory pipe and an inspiratory pipe, and these double pipes and the expiratory pipe. and connect with the intake pipe,
A breathing circuit device having a connector that connects one of the expiratory pipe and the inspiratory pipe to the inside of the inner pipe of the double pipe, and the other to connect the inner pipe and the outer pipe of the double pipe. At least the outer wall of the outer tube has irregularities, and the inner wall of the outer tube has a substantially smooth surface, and furthermore, there is a continuous hollow portion extending in the longitudinal direction of the inner tube and the outer tube. This is a breathing circuit device characterized by the absence of. Preferred embodiments thereof include the following. (i)' In the second invention, the outer walls of the expiratory pipe and the inspiratory pipe have irregularities, and the inner walls have substantially smooth surfaces. (ii)' In the second invention or (i)' above, the inner tube consists of an outer wall having an uneven surface and an inner wall having a substantially smooth surface. (iii)' In the second invention or (i)' or (ii)' above, the value obtained by dividing the difference in unevenness of the outer wall having unevenness by the minimum diameter of the inner wall is 0.01 to 0.13. (iv)' In the second invention or the above (i)' to (iii)',
The difference in unevenness of the inner wall, which is a substantially smooth surface, divided by the minimum diameter of the inner wall is 0.07 or less. (v)' In the second invention or the above (i)' to (iv)',
The value obtained by dividing the pitch of the uneven parts of the outer wall with unevenness by the minimum diameter of the inner wall is 0.1 to 0.6. (iv)' In the second invention or the above (i)' to (v)',
The value obtained by dividing the pitch of the uneven parts of the outer wall with unevenness by the minimum diameter of the inner wall is 0.1 to 0.6. (vii)' In the second invention or the above (i)' to (vi)',
The difference in the unevenness of the outer wall of the inner tube is 80% of the difference in the unevenness of the outer wall of the outer tube.
Must be below. (viii)' In the second invention or the above (i)' to (vii)',
The inside of the inner tube is the inhalation flow path, and the space between the inner tube and the outer tube is the exhalation flow path. (ix)' In the second invention or the above (i)' to (viii)',
The flow path inside the connector is concavely sloped downward.
It shall have a trap for stored water at its lowest point. (x)' In the second invention or the above (i)' to (ix)',
When the double tube is extended, the inner tube and the outer tube are arranged substantially coaxially. Specific Configuration of the Invention The specific configuration of the present invention will be described in detail below. The breathing circuit in the present invention includes not only a breathing circuit in a narrow sense but also an anesthesia circuit. 1 to 3 show an embodiment of the breathing circuit conduit of the first invention. As shown in these figures, the conduit 1 of the first invention consists of an outer tube 2 and an inner tube 3, each of which is flexible and has a different diameter, and which are arranged substantially coaxially. It consists of a double tube. In this case, ordinary flexible tube materials may be used for the outer tube 2 and the inner tube 3;
When using a normal breathing circuit conduit, it follows the external force such as bending without collapsing, and returns to its original state after the external force is released. The materials constituting the outer tube 2 and the inner tube 3 may be the same or different. For example, polyethylene, polypropylene, polyamide, polyvinyl chloride, polyester, polyurethane, polyvinyl acetate, ethylene-vinyl acetate. There are copolymers, etc. Of these inner tube 3 and outer tube 2, at least the outer tube has an outer wall having continuous irregularities and an inner wall consisting of a substantially smooth surface, and a continuous hollow portion extending in the longitudinal direction of the tube is provided within this wall. does not have At this time, kinking becomes even less,
It also makes it easier to drain the water that accumulates inside the outer pipe.
Moreover, pressure loss is reduced and compliance is also reduced. To describe the shape of the outer tube 2 in such a case more specifically, the outer wall 23 of the outer tube 2 is integrally formed with a U-shaped, V-shaped, etc. protruding strip 25.
In this case, a plurality of protrusions 25 are provided on the outer periphery of the tube in a cross section. Therefore, continuous spiral protrusions may be provided intermittently at equal or different pitches, and ring-shaped protrusions that do not form a spiral may be provided continuously or intermittently at equal or different pitches. Good too. However, in terms of manufacturing, it is preferable that the convex strip 25 is provided continuously in a spiral shape around the tube outer periphery along the tube longitudinal direction as shown in the drawing. On the other hand, the inner wall 21 of the outer tube 2 has a substantially smooth surface. Furthermore, between this inner wall 21 and outer wall 23,
There is no continuous hollow section extending in the longitudinal direction of the tube, and usually there are no interlocking hollow sections as shown. This indicates that the applicant of this application may use such a tube to use the continuous hollow portion for nebulizer operation or for use in various monitoring circuits.
This is because it has been proposed as an earlier application of this application (Japanese Unexamined Patent Publication Nos. 59-46973 and 59-46974). To explain the proposal from now on in more detail,
The proposed breathing circuit conduit 2 has a main pipe part 27, as shown in FIG. It has an auxiliary pipe section 29. That is, between the outer pipe 23 and the inner pipe 21 of the conduit 2, a continuous hollow part in a spiral shape extending in the longitudinal direction of the pipe is formed by the hollow part of the auxiliary pipe part 29. When compared with such tubes, the tube of the present invention has high strength because it does not have a hollow part.
It is more resistant to kinking, has less compliance, and is easier and cheaper to manufacture. In such a case, the difference in unevenness of the outer wall (lowest surface of the outer wall 2)
The value h/rmin obtained by dividing the height h) from 3 to the top of the protrusion 25 by the minimum inner wall diameter rmin is preferably 0.01 to 0.13, particularly 0.01 to 0.11. This greatly reduces kinking,
Compliance will also be significantly reduced. Furthermore, although it is preferable that the protrusions 25 are provided continuously in a spiral or non-spiral shape, the average pitch interval p of the protrusions (protrusions 25) is determined by the minimum diameter of the inner wall.
The value p/rmin divided by rmin is 0.1 to 0.6, especially 0.3
It is preferably ~0.5. It is preferable to provide the protrusions 25 at equal or different pitches within such a range of p/rmin values. At this time, the kinking was significantly reduced,
Compliance will also be significantly reduced. Furthermore, although the inner wall 21 is substantially smooth, the inner wall 21
As the smoothness tolerance of 1, the value obtained by dividing the unevenness difference of the inner wall 21 [Fig. 4 (rmax - rmin)] by the inner wall minimum diameter rmin is 0.07 or less, especially 0.05 or less, usually 0.01 ~
Preferably it is 0.05. This facilitates drainage of stored water and significantly reduces pressure loss. In addition, the wall thickness t of the outer tube 23 and inner wall 21 of the recess is
The value t/r divided by rmin is 0.001 to 0.03, especially
It is preferably 0.004 to 0.015. This reduces kinking, compliance, etc. In addition, the minimum diameter rmin of the inner wall of the outer tube 2 is 19 to 30 mm.
It is considered to be a degree. Such pipes are made of ethylene-vinyl acetate copolymer, polyvinyl acetate, polyvinyl chloride, polyethylene,
It is manufactured from the various thermoplastic resins mentioned above, such as polypropylene, by extrusion molding or by fusing protrusions. When using the outer tube 2 having such a shape, there is no particular restriction on the inner tube 3 to be used. That is, as the inner tube 3, a straight tube having smooth inner and outer wall surfaces may be used as shown in FIG. However, when the kinking of the inner tube 3 is reduced and the inner tube 3 is used as an inhalation flow path, and the space between the inner tube 3 and the outer tube 2 is used as an exhalation flow path, the heat retention effect of the exhaled gas is high, and the inspiratory gas is In terms of minimizing the drop in temperature, it is preferable to follow the following two embodiments. In the first embodiment, as shown in FIG. 1, a smooth internally serpentine tube having the same shape as the outer tube 2 and the same size ratio as described above is used as the inner tube 3. In such cases, the heat retention effect of the intake flow path is improved, kinking is reduced, the pressure loss of the expiration flow path is reduced, the pressure loss of the intake flow path is also reduced, and the drainage of accumulated water is facilitated. Effects such as reduced compliance will occur. On the other hand, in the second embodiment, as shown in FIG. 2, the inner tube 3 is a corrugated tube with an approximately uniform wall thickness and an uneven inner surface having unevenness (recesses 39, protrusions 37) on the inner and outer walls. This is when it is used. In such a case, in addition to improving the heat retention effect and reducing kinking, the pressure loss in the exhalation flow path is reduced, the drainage of stored water becomes easier, and compliance is reduced. Also in this case, it is preferable that the size ratio of the convex portions is the same as described above. In the above two embodiments, the unevenness difference (rmax-rmin) of the outer wall of the inner tube 3 is 80% or less, especially 40 to 80% of the unevenness difference (rmax-rmin) of the outer wall of the outer tube 2. (see Figure 4), the above effects are extremely significant. In such a double tube 1, the inside of the inner tube 3 is normally used as an inhalation flow path, and the space between the inner tube 3 and the outer tube 2 is used as an exhalation flow path. That is, in order to construct the breathing circuit device 5 using such a double tube 1, the exhalation tube 6 and the inhalation tube 7 are connected to the double tube 1 via the connector 8. An example of such a device 5 is shown in FIGS. 5 and 6. In the illustration, an outer tube 2 and an inner tube 3 of a double tube 1
is connected to connector 8. Also, connector 8
is connected to the exhalation pipe 6 and the intake pipe 7. In the connector 8, one of the expiratory pipes 6 and 7 (usually the inspiratory pipe 7) is connected to the inside of the inner pipe 3, and the other (usually the expiratory pipe 6) is connected to the inner pipe 3 and the outer pipe 2.
It is connected to the space between. In such a case, if the expiratory pipe 6 and the inspiratory pipe 7 are made of pipes having the above-mentioned shape and size ratio, with a smooth inner surface and a convex outer surface, as shown in the figure, the expiratory flow path and the intake pipe on the device side can be Exactly the same effect as described above occurs in the flow path as well. Further, the connector 8 can also be provided with a nebulizer or a check valve. Furthermore, as shown in the figure, trap cups 85 and 87 for stored water may be provided on the connector 8. In this case, as shown in the figure, the flow path inside the connector 8 is sloped, and a trap cup 8 is installed at the lowest part of the flow path.
5 and 87, the stored water can be easily and automatically drained into the trap cup, which is very convenient for handling. Note that a mouth connector 9 is usually connected to the other end of the double tube 1 on the patient side. Specific Effects of the Invention According to the first and second inventions, the movement of stored water within the circuit is facilitated, so that by simply adding a slight inclination to the circuit, the stored water can be collected in the trap or connected to the connector. The stored water can be easily drained out of the channel by simply removing and tilting it. Therefore, interruption of breathing of the patient due to draining time, which is required in conventional circuits, is eliminated or significantly shortened, and the load on the patient is reduced. Furthermore, since the gas flow path is smoothed, turbulence is less likely to occur, and the stored water is easily discharged, so that the rise in pressure loss is reduced and the patient's work of breathing can be reduced. Furthermore, since it does not collapse even when bent, there is extremely little risk of circuit blockage. Moreover, the elongation of the tube in the axial direction is reduced, and the compliance can be extremely reduced. According to the embodiments described above, these effects are extremely large. The present inventors conducted various experiments to confirm the effects of the present invention. An example is shown below. Example Using a flexible pipe with the dimensions shown in Table 1 below, Table 2
A double tube 1 shown in Figure 1 was fabricated. The material of the component tube was ethylene-vinyl acetate copolymer (EVA). In addition, the total length of the double pipe is 0.6 m (Fig. 7
_l1 ). Using this double tube 1, a breathing circuit device 5 having the structure shown in FIGS. 5 and 6 and the dimensions shown in FIG. 7 and Table 2 was manufactured. In this case, the expiratory pipe 6 and the intake pipe 7 are as follows:
The flexible tubes for outer tubes shown in Table 1 were used as shown in Table 2.

【table】

[Table] 3 3 1 1

Claims (1)

[Claims] 1 Two flexible tubes with different diameters, one of which is an inner tube and the other an outer tube, are used as a double tube, and the inner tube and between the inner tube and the outer tube are made into a double tube. In a breathing circuit conduit with a gas flow path, at least the outer wall of the inner tube and the outer tube has irregularities, the inner wall of the outer tube has a substantially smooth surface, and the inner tube has an uneven surface. A conduit for a breathing circuit, characterized in that there is no continuous hollow portion extending in the longitudinal direction of the tube within at least one wall of the outer tube. 2. The conduit for a breathing circuit according to claim 1, wherein the inner tube comprises an outer wall having an uneven surface and an inner wall having a substantially smooth surface. 3. The conduit for a breathing circuit according to claim 1 or 2, wherein the value obtained by dividing the unevenness difference of the outer wall having unevenness by the minimum diameter of the inner wall is 0.01 to 0.13. 4. The breathing circuit conduit according to any one of claims 1 to 3, wherein the difference in unevenness of the inner wall, which is a substantially smooth surface, divided by the minimum diameter of the inner wall is 0.07 or less. 5. The conduit for a breathing circuit according to any one of claims 1 to 4, wherein the value obtained by dividing the pitch of the convex portions of the outer wall having irregularities by the minimum diameter of the inner wall is 0.1 to 0.6. 6 The difference in the unevenness of the outer wall of the inner tube is 80% the difference in unevenness of the outer wall of the outer tube.
% or less, the conduit for a breathing circuit according to any one of claims 1 to 5. 7. The conduit for a breathing circuit according to any one of claims 1 to 6, wherein the interior of the inner tube is an intake flow path, and the space between the inner tube and the outer tube is an intake flow path. 8. The breathing circuit conduit according to any one of claims 1 to 7, wherein the inner tube and the outer tube are arranged substantially coaxially when the double tube is extended. 9. Two tubes each having flexibility and different diameters are connected to a double tube with one as an inner tube, an expiratory tube and an inspiratory tube, and these double tubes, an expiratory tube and an inspiratory tube,
A breathing circuit device having a connector that connects one of the expiratory pipe and the inspiratory pipe to the inner pipe of the double pipe, and the other to the inner pipe and the outer pipe of the double pipe, wherein the inner pipe and the outer pipe are connected to each other. At least the outer wall of the outer tube has irregularities, and the inner wall of the outer tube has a substantially smooth surface, and furthermore, at least one of the inner and outer tubes has a continuous hollow extending in the longitudinal direction of the tube. A breathing circuit device characterized in that there are no parts. 10 The outer walls of the expiratory pipe and the inspiratory pipe have irregularities,
The breathing circuit device according to claim 9, wherein the inner wall has a substantially smooth surface. 11. The breathing circuit device according to claim 9 or 10, wherein the inner tube comprises an outer wall having irregularities and an inner wall having a substantially smooth surface. 12. The breathing circuit device according to any one of claims 9 to 11, wherein a value obtained by dividing the unevenness difference of the outer wall having unevenness by the minimum diameter of the inner wall is 0.01 to 0.13. 13. The breathing circuit device according to any one of claims 9 to 12, wherein the difference in unevenness of the inner wall, which is a substantially smooth surface, divided by the minimum diameter of the inner wall is 0.07 or less. 14. The breathing circuit device according to any one of claims 9 to 13, wherein the value obtained by dividing the pitch of the convex portions of the outer wall having irregularities by the minimum diameter of the inner wall is 0.1 to 0.6. 15 The difference in the unevenness of the outer wall of the inner tube is the difference in the unevenness of the outer wall of the outer tube.
Claims 9 to 1 that are 80% or less
4. The breathing circuit device according to any one of Item 4. 16. The breathing circuit device according to any one of claims 9 to 15, wherein the interior of the inner tube is an inhalation flow path, and the space between the inner tube and the outer tube is an exhalation flow path. 17. The breathing circuit device according to any one of claims 9 to 16, wherein the flow path in the connector is concavely inclined downward, and has a trap for stored water at the lowest part thereof. 18 Claim 9, wherein when the double tube is extended, the inner tube and the outer tube are arranged substantially coaxially.
The breathing circuit device according to any one of Items 1 to 17.