JPS59203568A - Cannula - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new type of cannula, and more particularly to a new form of cannula suitable for cardiac surgery.

Conventionally, a heart-lung machine has been used in heart surgery. This kind of cannire is shown in Figure 1 (
Either the tip is not provided with a flange as shown in a), or even if there is a flange, the outer periphery of the tip is perpendicular to the longitudinal center line of the cannula as shown in Figure 1(b). There are only those provided in

During heart surgery, the inserted tip of the cannula is fixed to the wall of the heart or blood vessel wall with a purse string suture, etc., but the tip of the cannula does not have a collar. In the case of ..., the insertion tip is likely to fall off, and especially when an auxiliary artificial LBW is used, there is a great risk of it falling off due to its prolonged pulsation, which can be a fatal problem. Furthermore, when an auxiliary artificial heart is used, it is used for a long period of time, so if a large amount of anticoagulant such as heparin is used, the patient tends to bleed, which is not suitable. For this reason, if the use of heparin is suppressed, the blood retention area formed in the sutured and fixed portion is likely to cause a frame, which also poses a fatal problem.

Even if a cannula is provided with a collar on the outer periphery of the distal end, the cannula shown in FIG. Due to its structure, the collar (2) is provided on the outer periphery of the canyule (!)
However, they do not fit tightly, and as a result, blood accumulates in the bulge of the brim, which is a fatal problem that can lead to blockages. If you try to force the brim of the casing to come into close contact with the heart or blood vessel wall, it will cause a corresponding strain on the heart or blood vessels and the stress that accompanies it, which will drastically reduce the effectiveness of using an auxiliary artificial heart to connect the whole myocardium. It will end up being put away.

Moreover, with the progress of heart surgery, for example, the use of an artificial heart or an auxiliary artificial stone Ifξ years old (hereinafter referred to as an auxiliary artificial heart) allows for long-term use of the cannile, and the use of an artificial heart with equal curvature on the back side of the heart. It is necessary to insert the cannula into a large curved surface, and in these cases, there is a problem that the above-mentioned conventional cannula cannot be used.

The present invention skillfully solves these problems, and is a cannula that facilitates and securely fixes the insertion tip, and has a structure that prevents blood flow from occurring easily. The minimum angle between the center line and any straight line passing through the longitudinal center line of the inner hole of the cannula, which is the flow path, and passing through two points on the maximum outer circumference line of the boxwood part, is between soo and the provided collar part. An embodiment of the present invention having an inclined cannula 800 will be described below with reference to the drawings.

FIG. 2 shows an embodiment in which the inner diameter is the same over the entire length, and the flange is inclined with respect to the length direction of the cannula, which is suitable for use as, for example, a blood removal cannula for a heart-lung machine.

FIG. 3 shows another embodiment, in which a thin tube tube communicating with the insertion tip and a thick tube tube communicating seamlessly with the thin tube tube and having an inner diameter smaller than that of the thin tube tube are integrally constructed. This is an embodiment of the cannula in which the collar is inclined with respect to the longitudinal direction of the thin tube.
It is suitable for blood removal cannulation for left ventricular assist. Tube Cheap's A, B, C! Each point is bent in a different direction, and a metal spiral is installed inside this portion to prevent the kinking phenomenon (bending phenomenon).

Preferably, the minimum angle formed between an arbitrary straight line passing through two points on the maximum outer circumference of the collar and the longitudinal center line of the circular hole, which is the flow path of the cannula, is 60° to 80°. is provided at an angle of 50° to 75° on the outer periphery of the cannula insertion tip. Outside the above range, the compatibility and fixation of the limb with the heart wall or blood vessel wall will be poor, resulting in blood stagnation and thrombus formation as described above, which goes against the purpose of the invention. .

Since the shape of the heart is a collection of complex curved bodies, anatomically the above-mentioned range of 50° to 75° is preferable. The height of the protrusion of the collar from the outer wall of the cannula is 1 mm-5.
It is preferable that it be formed in the range of rlun.

If it is less than 1 inch, the effect of providing the brim part for fixation and anti-thrombosis will be poor, and if it is more than 5 inches, the incision for insertion will become large and unnecessary invasion of the myocardium and blood vessel wall will be avoided. This is because the position of the flange formed on the outer periphery of the insertion tip of the O-canineer is preferably between 50 and 50 degrees from the insertion tip, as shown in FIG. 4(a).
It may also be provided at the insertion tip as shown in b). Figure 4(a)
The cannula shown in Fig. 1 is suitably used as a cannula for feeding blood to the aorta during heart surgery.

The shape of the brim portion can be arbitrarily formed depending on the purpose and the shape and region of the target heart, but the point is that it can be formed to fit closely with the heart wall or blood vessel wall.

For example, as shown in FIG. 4(-), both sides of the boxwood portion may be substantially flat and formed symmetrically around the outer periphery of the insertion tip of the cannula. Figure 5(a) shows the state in which this tip is inserted into the aorta, and as shown in the figure,
The collar part (2
) fits tightly into the aortic vessel wall (3).

Further, in consideration of blood flow and the like, it may be formed into an umbrella shape with a taper on the insertion surface side as shown in FIG. 5(b).

On the other hand, in the case of a child whose heart has a large curved surface, the insertion tip side surface can be made almost flat, and the other side surface can be tapered, as shown in FIG. 5(C). . In any case, as shown in Figure V, the heart wall and the brim are in close contact and fixed together.

FIG. 6 shows an example in which the cannula according to the present invention is used during surgery on the heart 1 using an auxiliary artificial heart.

Cannile (1A) is enclosed for aortic blood supply.
The insertion tip is inserted into the aorta (3A), and the other end is connected to the auxiliary artificial heart (4). The inserted state of the insertion tip in this case is shown in FIG. 60). The brim is shown in Figure 4 (-)
As shown in the figure, both surfaces are formed substantially flat, and an angle of 60° is formed between a straight line passing through two points on the maximum outer circumferential line and the center line in the length direction of the cannula inner hole.

On the other hand, the Neele (1B) is used for blood removal from the left heart, with its tip inserted into the left atrium and the other end inserted into the auxiliary artificial heart (
4). The above-mentioned forming angle of the flange portion 2) in this cannile is 70°, and both wide surfaces are formed in a substantially flat shape.

According to this embodiment, the collar of the cannula is attached to the blood vessel wall (3A).
Or, it fit closely with the heart wall (5B), and no thrombus occurred at the joint part even after one month of use.

As already explained, with the development of heart surgery, (auxiliary)
Development of an artificial heart is progressing. However, the current situation is that there is currently no crab yule suitable for this purpose, so the Ahiro patented canyule has made this possible.A representative example of a crab yule that satisfies this requirement is shown in Fig. 3, which has already been explained. There's Canile.

In this case, the inner diameter of the cannula is preferably within the range of 3 m to 15 m for thin tubes.

In other words, when using a cannula for heart surgery, if the inner diameter of the relatively thin part (tubule) of the part that bypasses the right heart from the insertion tip is smaller than 3 mm, the pressure drop will be large and the heart of the (auxiliary) artificial heart will be damaged. The function deteriorates and if the cage is larger than 15, it will put pressure on the patient's heart. For large pipes, the inner diameter must be 8 or more diameter to minimize pressure loss, and 2511
If it is larger than 11I11, a separate connector will be required when connecting to the auxiliary artificial heart, and therefore blood flow will likely stagnate in that area, which is undesirable.

The wall thickness of the cheep is also an important factor in the cannile according to the present invention. In other words, if the thickness of the tubular portion is less than 0.2W, there is a problem that pulsating swelling is likely to occur due to rapid extraction from the heart, and furthermore, it is impossible to embed a reinforcing metal spiral. If the cannula is thicker than this, the cannula will not be thick enough and will put pressure on the heart, which is not preferable. In addition, since the thick tube portion is connected to the (auxiliary) artificial heart during use, it must be cut to an appropriate length, and therefore it is not possible to reinforce the spiral. Therefore, the thickness must be at least 12TnIII in order to prevent the kinking phenomenon (bending phenomenon). On the other hand, if it takes more than 7 days, it becomes thicker and becomes less workable. The ratio of the length of the canal to the length of the canal is determined by adjusting the length of the cannula during surgery based on the shape of the patient's heart. A certain length is required because it must be adjusted instantaneously. On the other hand, if it is too long, it is unsuitable from the viewpoint of workability and cost, and in this case, it is optimal that the length of the large tube section is in the range of 0.1 to 1 to the length of the narrow tube section of 1.

In order to prevent deformation due to pulsation during use of this cannula, the cannula should have the above-mentioned wall thickness, and at least
The part near the tip of the re, i.e. the tubular part with a small inner diameter (
It is a good idea that the ME pipe is reinforced with a metal spiral inside.

The most suitable material for the cannula is polyurethane or polyvinyl chloride containing a plasticizer. As the polyurethane, commonly used polyester polyurethanes and polyether polyurethanes are commonly used.

Molded products using these polyurethanes may be crosslinked to increase their mechanical strength.

Polyester-based polyurethanes are preferred as non-inventive materials because they are suitable for producing hard entomers with high elastic modulus and high tear strength.

The ratio of crosslinking agent is 0.0 to the total amount of polyurethane components.
The amount is preferably 1 to 5% by weight. As the polyvinyl chloride plasticizer, known polyvinyl chloride plasticizers such as dioctyl phthalate and dioctyl adipate are widely used. In this case, the flexible polyvinyl chloride may be formed from a so-called polyvinyl chloride paste consisting of polyvinyl chloride and a plasticizer composition.

In this case, the mixing amount of the plasticizer is preferably 40 to 100 parts per weight, more preferably 50 to 80 parts per weight of polyvinyl chloride.

The polyvinyl chloride may also contain suitable known stabilizers, such as non-toxic calcium-zinc organic complexes. The degree of polymerization of polyvinyl chloride is 500 to 2000
In order to improve the antithrombotic property of the cannile of the present invention, the inner surface that comes into contact with blood can be coated with a known antithrombotic material to improve blood compatibility.

As explained above, the cannula according to the present invention is suitably used during heart surgery, and by making the flange part specific, it can be easily used during the surgery.

The insertion tip of the cannula can be easily and securely fixed, and the formation of thrombi is difficult to occur. By forming it integrally and having a shape with a special curve, it can be suitably used for heart surgery using an (auxiliary) artificial heart.

[Brief explanation of the drawing]

Figure 1 is a plan view of conventionally used cannulae. It is a state diagram when it is pushed into the core. Figure 2 is a slope view of the canile according to the invention;
The figure is a perspective view of another embodiment of the cannula according to the present invention, which is suitable for use with an (auxiliary) artificial heart. FIG. 4 is a perspective view showing the formation of the lobes '6L II'i, and FIG. 5 is a sectional view showing the state of close contact between the lobes and the heart wall. In the reference numerals, 1 indicates the cannula, 2 indicates the collar, and 6 indicates the heart wall or 11 the canal wall. Figure 2 Figure 3 Figure 4 (0-) Figure 4 (b) Dream S 12 (tsu procedural amendment (method) December 1982 I Mr. L of the Commissioner of the U.S. Patent Office L Display of the case 1982 Patent Application No. 107288 2 Title of the invention Canyule 3 Person making the amendment 4 Date of amendment order November 29, 1982 (shipment date) !lk The text of the subject of amendment "Brief explanation of drawings" has been amended as follows: 4. Brief explanation of the drawings Figure 1 is a plan view of a conventionally used cannula. ) is a diagram of the cannula of (b) inserted into the heart; FIG. 2 is a perspective view of the cannula according to the present invention; and FIG. 3 is a perspective view of another embodiment of the cannula according to the present invention. Figure 4 is a slanted view showing the formation position of the ``part'', and Figure 5 shows the relationship between the ``part'' and the heart wall. Fig. 6(a) is a sectional view showing the state in which the cannula according to the present invention is used in heart surgery, and Fig. 6(b) shows the state in which the insertion tip is inserted. It is a partial sectional view.In the symbols, 1 indicates a cannula, 2 indicates a collar, and 3 indicates a heart wall or a blood vessel wall.

Claims (1)

[Claims] 1. In a cannula having a bulge on the outer periphery of the insertion tip, a center line in the longitudinal direction of the circular hole of the cannula, which is a flow path, and on the maximum outer circumference line of the boxwood part. The cannula is characterized in that the boxwood portion is provided at an angle on the outer periphery of the insertion tip, with a minimum angle between 60° and 800° between any straight line passing through two points.