WO2014191594A1

WO2014191594A1 - Improved endotracheal tube

Info

Publication number: WO2014191594A1
Application number: PCT/ES2014/070419
Authority: WO
Inventors: Emilio CURIEL BALSERA; Juan Guillermo QUESADA GARCIA; Juan MORA ORDOÑEZ; Javier MUÑOZ BONO
Original assignee: Servicio Andaluz De Salud
Priority date: 2013-05-27
Filing date: 2014-05-21
Publication date: 2014-12-04
Also published as: ES2525962B1; ES2525962A2; ES2525962R2

Abstract

The invention concerns a novel, improved endotracheal tube (1) designed in particular to make it difficult for fluids or secretions to enter a patient's trachea owing to the fact that its outer surface comprises at least one protuberance (2a, 2b, 2c) configured such that, when the tube (1) is in use, it causes the detachment of the fluids which move along the outer surface of the tube (1) towards the distal end thereof, such that they fall downwards owing to the effect of gravity.

Description

IMPROVED ENDOTRAQUEAL TUBE

OBJECT OF THE INVENTION The present invention belongs to the field of medicine, and more specifically to the field of devices used to perform artificial ventilation of a patient.

The object of the present invention is a new endotracheal tube specially designed to hinder the entry of secretions or fluids into a patient's trachea.

BACKGROUND OF THE INVENTION

When a patient has a serious pathology or is going to undergo an important surgical intervention, it must be artificially ventilated. To be able to ventilate a patient in this way, a tube is placed that has a proximal end that protrudes outward through the patient's mouth or nose and a distal end that ends in the trachea. These tubes have a pneumotoping next to its distal end that takes the form of an inflatable balloon or balloon whose functions are to fix the tube so that it does not enter more or accidentally comes out, isolate the airway from secretions that may come from the mouth , and ensure that the air is blown through that tube to the lungs and not into the mouth.

A relatively frequent complication in ventilated patients is the development of respiratory infections, such as tracheobronchitis, or even more serious ones, such as pneumonia associated with mechanical ventilation (NAVM). The current incidence of NAVM is very variable from one country to another, ranging from 2 to 16 cases per 1000 days of mechanical ventilation, with an attributable mortality of 3-17%. Therefore it is a problem of great magnitude in the resuscitation and intensive care units of any hospital with serious repercussions on the stay, costs and mortality of these patients.

Although the causative factors of these infections are multiple, the aspiration of contaminated secretions from the mouth or of regurgitated gastric contents through the upper airway to the tracheobronchial tree plays a fundamental role. These secretions circulate along the outer surface of the endotracheal tube until reaching the area of pneumotransposition. In this place they accumulate and cause repetitive microfiltration to the tracheal tree, which in turn is the ultimate cause of many respiratory infections. To avoid this problem, currently known endotracheal tubes propose improvements aimed at improving the tightness of the closure in the area of pneumotoping in order to prevent the passage of secretions to the tracheal tree or suction devices connected to a hole in the area immediately above the pneumotrop. US 2013/0047992 describes an endotracheal tube equipped with a corrugated pneumotoping, where each corrugation or groove constitutes a kind of seal that improves the tightness of conventional pneumotopings.

Document US 2012/0279505 describes an endotracheal tube equipped with two consecutive pneumotopings and a conduit that allows filling the space between them with a gel or a gas to increase the tightness.

However, these solutions are relatively complex, which makes the final product considerably more expensive. In addition, the problem is not definitively solved, since secretion leaks continue to end up reaching the tracheal tree, with the consequent appearance of infections.

DESCRIPTION OF THE INVENTION The inventors of the present application have discovered that the secretions of the mouth reach the place where the pneumotoping is located to subsequently reach the trachea, thanks to the fact that they circulate along the outer surface of the tube by effect of surface tension. In fact, in the position in which the patient is normally intubated most of the time, lying on his back, the larynx and trachea are located at a level higher than the hypopharynx and esophagus, so the fluids from the mouth would not reach the trachea if they did not have the "path" that constitutes the endotracheal tube itself. In other words, without the help of the endotracheal tube, the secretions would simply fall by gravity to the hypopharynx area, where they would be swallowed by the patient through the esophagus. In view of this, instead of trying to minimize the problem by increasing the tightness of the pneumotoping, as has been done so far in the prior art, the inventors of the present application propose to act on the shape of the tube itself to cut the path they travel. the secretions, so that these stop their advance and fall by gravity to the hypopharynx or the posterior area of the oropharynx, place from which it is easy to aspirate them by the medical staff or swallow them by the patient himself through the esophagus. This new solution path is not only surprisingly effective, but also its implementation is simpler and cheaper compared to prior art systems.

A first aspect of the invention is directed to an improved endotracheal tube characterized in that its outer surface comprises at least one protuberance configured such that, when said tube is in use, it causes the detachment of fluids that travel along of said outer surface of the tube in the direction of its distal end, causing them to fall down by gravity. Therefore, unlike prior art documents, the protuberances of the invention are not necessarily elastic nor are they configured to hermetically contact the walls of the patient duct where they are located. On the contrary, at least the lower part of the protuberances of the invention does not touch the patient's conduit where the tube is placed, thus allowing the secretions to fall towards the hypopharynx.

In principle, the at least one protuberance can take various forms as long as they manage to release the fluids that run through the tube, that is, cause them to separate from the tube and fall by gravity towards the posterior area of the patient's oropharynx. Extrusions with acute angles directed downwards can be used, so that secretions cannot overcome the obstacle and become trapped by hanging from them. Thus, as the volume increases, and therefore the weight, of the fluid trapped in the protuberance, there comes a time when it separates from it and falls by gravity. In a preferred embodiment of the invention, the protuberances are based on the outer surface of the endotracheal tube, thereby necessarily protruding above said surface. However, to avoid the risk that said protuberances may cause lesions in the mucosa of the hypopharynx and oropharynx, in an alternative preferred embodiment the protuberance or protuberances are based on a narrowed area relative to the outer surface of the tube. This narrowed area normally It is also cylindrical but with a narrower diameter, so that it is possible to ensure that the protuberances do not protrude above said outer surface of the tube. That is, in this case a section of smaller diameter is excavated in the tube wall itself, and the protuberance is incorporated in that area of smaller diameter so that its height does not exceed that of the tube itself in areas of normal diameter . You could say that it would be somewhat similar to the drawing of a tire, where instead of projections, what it has are grooves carved into the rubber.

In a preferred embodiment, the protuberances protrude only on one side of an imaginary plane containing the longitudinal axis of the endotracheal tube. Normally, current endotracheal tubes have a slight preformed curvature indicating their preferred position of use, so that these protuberances would be on the concave side of said tubes. In this case, medical personnel should be careful when placing the endotracheal tube to ensure that the protrusions protrude from the bottom of the tube once it is placed in the patient.

In any case, even if the tubes are provided with said curvature that indicates the preferred position of use, it is customary to place them in another position. Therefore, in another alternative preferred embodiment, the at least one protuberance has an essentially annular shape surrounding the tube. Thus, medical personnel do not have to worry about the orientation according to which they place the endotracheal tube of the invention, since in any case there will be a part of the protrusion protruding downwards to cause the detachment of fluids or secretions. Preferably, the at least one protuberance is an annular prism of rectangular section, such as an essentially flat flange.

Preferably, the at least one protuberance is an annular prism of essentially triangular section.

Preferably, the at least one protuberance is an annular prism of essentially semicircular shape.

As for the dimensions of the protuberances, these should be large enough to achieve the detachment of the fluid that advances along the tube, and at even small enough not to cause lesions in the mucosa of the hypopharynx and oropharynx. For example, each protuberance can have a thickness of between 0.2 cm and 0.5 cm and a height from its base of approximately between 0.4 cm and 0.8 cm. In relation to the position, taking into account the position of the intubated patient and the length of insertion of the distal end of the endotracheal tube into the patient's trachea (approximately 1-2 cm beyond the vocal cords), the at least one bulge will be located in a section of tube that goes from the midpoint of the tube to a third of its length before the distal end.

Note that although this document refers to "at least one" protuberance, the scope of the same includes from a single protuberance to a plurality thereof that could occupy a whole section of endotracheal tube. In this second case, the section of protuberances could cover the entire tube portion described in the previous paragraph, that is, from the midpoint of the tube to a third of its length before its distal end.

So far, the case in which the protuberances form an integral part of the endotracheal tube of the invention has been described. However, it is also possible that the at least one protuberance is incorporated in a hollow cylindrical piece designed to engage a conventional endotracheal tube. Thus, to obtain the advantages of the present invention, medical personnel could use any conventional endotracheal tube to which only said cylindrical part fitted with protuberances would have to be attached before proceeding to its placement in the patient.

Therefore, a second aspect of the invention is directed to a hollow cylindrical part that comprises at least one protuberance and which is configured to be coupled to a detachable endotracheal tube, such that, when said tube is in use, said less a bulge causes the detachment of fluids that travel along the outer surface of said tube in the direction of its distal end, causing them to fall down by gravity.

In order to ensure that the hollow cylindrical part can be coupled and decoupled from any conventional endotracheal tube, preferably said hollow cylindrical part is made of an elastic material and comprises a longitudinal groove configured to allow its opening to couple and decouple it from the endotracheal tube. Thus, the medical staff would only have to "open" the piece through the longitudinal groove with their fingers exerted a force directed towards the outside, then introduce the conventional tube through the groove, and finally release the edges of the groove to allow that the piece recover its cylindrical shape "hugging" the conventional tube thanks to its elasticity. The cylindrical piece would, for practical purposes, become part of the longitudinal tube, providing it with protuberances.

The protuberances of the hollow cylindrical part described are of the same characteristics as in the case of forming an integral part of an improved endotracheal tube as described above. Specifically, the at least one protuberance may protrude on one side of an imaginary plane containing the hollow cylindrical piece, or it may have an essentially annular shape that surrounds the entire cylindrical part. The protuberance can be: an annular prism of rectangular section, such as an essentially flat flange; an annular prism of essentially triangular section; or an annular prism essentially semicircular.

The at least one protuberance can have a thickness of between 0.2 cm and 0.5 cm and a height from its base of approximately between 0.4 cm and 0.8 cm.

As for the dimensions of the hollow cylindrical piece, it can be between 3 cm and 8 cm long.

BRIEF DESCRIPTION OF THE FIGURES

Fig. 1 shows an endotracheal tube according to the prior art.

Fig. 2 shows an endotracheal tube according to the prior art already placed in a patient.

Figs. 3a-3b show two examples of endotracheal tube according to the invention, the first with the protuberances protruding from the surface of the tube, and the second with the protuberances arranged in a narrowed or recessed portion of the tube. In both cases the bumps are eyelashes. Figs. 4a-4c show details of protrusions protruding from the surface of a tube according to the present invention where they are appreciated respectively: protrusions in the form of a triangular annular prism, protrusions in the form of a semicircular annular prism, and protrusions in the form of tabs annular

Figs. 5a-5c show details of protrusions arranged in a narrowed area of a tube according to the present invention where they are appreciated respectively: protrusions in the form of a triangular annular prism, protrusions in the form of a semicircular annular prism, and protrusions in the form of tabs annular

Fig. 6 shows a schematic view of an endotracheal tube like that of Fig. 3a installed in a patient.

Figs. 7a-7b show an example of a hollow cylindrical piece designed to be coupled to a conventional endotracheal tube respectively with its natural shape and with its open groove for coupling to a conventional endotracheal tube.

Fig. 8 shows a conventional endotracheal tube with the hollow cylindrical part of Fig. 6 coupled thereto.

PREFERRED EMBODIMENT OF THE INVENTION

Fig. 1 schematically shows a conventional endotracheal tube (100). It can be seen how it has a pneumotoping (100a) at its distal end that is designed to be able to swell from the outside so that it fits the walls of the patient duct where it is installed. The opposite proximal side (100b), in turn, protrudes outside the patient's mouth for connection to a mechanical ventilator or similar device. In the examples that follow, the endotracheal tubes (100, 1) shown in the figures are shown schematically, although a person skilled in the art will readily understand that they can include multiple additional elements.

As can be seen in Fig. 1, when the tube (100) is properly placed in the patient, and in addition it is lying on its back, as normally occurs most of the time with the intubated patients, the patient's trachea is at a higher level in relation to the hypopharynx. As a result, normally also the endotracheal tube (100) has a small upward slope from its lowest point to the area of pneumotoping next to the trachea. In view of this, in order for the fluids or secretions from the patient's mouth to reach the trachea and potentially cause respiratory problems, they must advance "stuck" to the tube itself (100) thanks to the surface tension. Given the completely smooth configuration of conventional endotracheal tubes (100), this is quite simple. Fig. 1 schematically shows how the fluids or secretions from the patient's mouth advance attached to the tube (100) until entering the area of the trachea. The pneumotoping (100a) is shown in this deflated figure and in a schematic way, although it is understood that it would form a plug in the trachea where the fluids would accumulate, which could gradually end up entering the patient's tracheal tree.

Compared to the solutions proposed in the known endotracheal tubes (100) consisting of adding additional means at its distal end to improve the tightness of the joint formed by the pneumotoping (100a), or in modifying the pneumotoping itself (100a) with the same purpose, the present invention proposes to include protuberances (2a, 2b, 2c) in a middle area of the endotracheal tube (1). This solution cuts the advance of the secretions in a simple way, solving the root problem by preventing the secretions from reaching the area of pneumotoping (1 a).

This is seen in greater detail in Fig. 3a, where an improved endotracheal tube (1) according to the present invention has been shown. In this example, the tube (1) has essentially the same constitution as a conventional tube (100), with the difference that it also comprises an area of protuberances (2a) located in a middle area of the endotracheal tube (1). That is, the protuberances (2a) are "born" from the surface of the tube (1) itself, and a certain height protrudes from its surface. Fig. 3b shows another example of endotracheal tube (1) where the protuberances (2a) "are born" or have their base in a portion of the tube (1) that has a smaller or narrower diameter relative to the outer surface of the tube . In this context, the outer surface of the tube is the cylindrical surface that constitutes most of the length of the tube. In this way, the protuberances (2a) protrude less above the outer surface of the tube, and can even be flush with it as in Fig. 3b, minimizing the possibility of damaging the hypopharyngeal mucosa and the patient's oropharynx.

In the example shown in Figs. 3a and 3b, the protuberances (2a) take the form of annular tabs that completely surround the improved endotracheal tube (1). However, Figs. 4a-4c and 5a-5c show other examples of possible forms that could be used respectively in the case of protrusions (2a, 2b, 2c) that are based on the outer surface of the endotracheal tube and protuberances (2a, 2b, 2c ) having their base in a narrowed portion of the tube (1) relative to its outer surface. Figs. 4a and 5a show protrusions (2c) in the shape of an annular prism of triangular section. Figs. 4b and 4c show protrusions (2b) in the form of an annular prism of semicircular section. Figs. 4c and 5c show the protuberances (2a) in the form of an annular prism of rectangular section, in this case essentially flat tabs. In any of the cases, the effect achieved by means of these protuberances (2a, 2b, 2c) is to stop the advance of the secretions that advance through the tube (1), as observed in Fig. 6. Indeed , the secretions advance along the surface of the tube that has an inclined or downward orientation. However, upon reaching the bulge zone (2a) of Fig. 6, the secretions descend to the edge of the eyelashes (2a) and then must "rise" to return to the surface of the improved endotracheal tube (1). However, this small upward displacement is not possible without a greater accumulation of fluid, which has the effect of increasing the weight of liquid trapped at the lower edge of the eyelashes (2a). Gradually, drops are formed that, when the force of gravity that pulls down exceeds the surface tension that keeps them attached to the eyelashes (2a), they fall into the area of the hypopharynx. In this area, they do not represent any problem, since they can be easily swallowed by the patient or aspirated by medical personnel. As in the previous case, in this example the pneumotoping (1a) is represented schematically deflated, although it is understood that it would be coupled to the trachea walls.

So far the figures have represented an improved endotracheal tube (1) where the protuberances (2a, 2b, 2c) form an integral part thereof. However, as described above, there is also the possibility that the protuberances (12a, 12b, 12c) are part of an independent part (10), and that this part (10) can be coupled to any tube (100) Conventional endotracheal similar to that shown in Figs. 1 and 2. Figs. 7a and 7b show an example of a hollow cylindrical part (10) having a series of protuberances (12a, 12b, 12c), which in this example are also ring tabs (12a) annular and essentially flat. It is understood, however, that the protuberances (12a, 12b, 12c) of the part (10) could be of any of the types mentioned above. In general, it should be understood that all features, dimensions, etc. mentioned for the protuberances (2a, 2b, 2c) of the improved endotracheal tube (1) are also valid for the protuberances (12a, 12b, 12c) of the hollow cylindrical part (10). As for its length, the cylindrical part (10) of this example measures approximately 5 cm, although as mentioned above it could measure between 3 cm and 8 cm. It has been found that this length is best suited to fit the area of the larynx just above the epiglottis, so that the drop in severity of secretions reaches the hypopharynx.

This piece (10) has a longitudinal groove (3) that runs it completely from one end to the other. Thus, as seen in Fig. 7b, the elasticity of the piece (10) itself allows medical personnel to "open" the groove manually by pulling its edges and attaching it to a conventional tube (100). The result is shown in Fig. 8, where the part (10) is already coupled to the conventional tube (100). The protuberances (12a) are thus incorporated into said conventional tube (100), which thereby acquires the ability to stop the flow of secretions in a manner equivalent to the improved tube (1) described above.

Claims

1. Improved endotracheal tube (1), characterized in that its outer surface comprises at least one protuberance (2a, 2b, 2c) configured such that, when said tube (1) is in use, it causes the detachment of the fluids that are they move along said outer surface of the tube (1) towards its distal end, causing them to fall down by gravity.

2. An improved endotracheal tube (1) according to claim 1, wherein the at least one protuberance (2a, 2b, 2c) is based on the outer surface of the tube (1).

3. An improved endotracheal tube (1) according to claim 1, wherein the at least one protuberance (2a, 2b, 2c) is based on a narrowed section of the tube (1) relative to its outer surface.

4. An improved endotracheal tube (1) according to claim 3, wherein the height of the at least one protuberance (2a, 2b, 2c) does not exceed the outer surface of the tube (1).

5. Improved endotracheal tube (1) according to any of the preceding claims, wherein said at least one protuberance (2a, 2b, 2c) has an essentially annular shape surrounding the tube (1).

6. An improved endotracheal tube (1) according to claim 5, wherein said at least one protuberance (2a) is an annular prism of rectangular section.

7. An improved endotracheal tube (1) according to claim 6, wherein said annular prism (2a) of rectangular section is an essentially flat flange.

8. An improved endotracheal tube (1) according to claim 5, wherein said at least one protuberance (2b) is an annular prism of essentially semicircular shape.

9. An improved endotracheal tube (1) according to claim 5, wherein said at least one protuberance (2c) is an annular prism of essentially triangular section.

10. Enhanced endotracheal tube (1) according to any of the claims above, where the at least one protuberance (2a, 2b, 2c) has a thickness of between 0.2 cm and 0.5 cm and a height from its base of approximately between 0.4 cm and 0.8 cm.

1 1. Improved endotracheal tube (1) according to any one of the preceding claims, wherein the at least one protuberance (2a, 2b, 2c) is located in a section of the improved tube (1) running from the midpoint of the tube up to a third before its distal end

12. Hollow cylindrical part (10) characterized in that it comprises at least one protuberance (12a, 12b, 12c) that is configured to cause the detachment of fluids that travel along the outer surface of an endotracheal tube (100) in direction to its distal end, where said hollow cylindrical part (10) is configured to engage said endotracheal tube (100) detachably.

13. Hollow cylindrical part (10) according to claim 12, wherein said at least one protuberance (12a, 12b, 12c) has an essentially annular shape surrounding the tube (1).

14. Hollow cylindrical part (10) according to claim 13, wherein said at least one protuberance (12a) is an annular prism of rectangular section.

15. Hollow cylindrical part (10) according to claim 14, wherein said annular prism (12a) of rectangular section is an essentially flat flange.

16. Hollow cylindrical part (10) according to claim 13, wherein said at least one protuberance (12b) is an annular prism of essentially semicircular shape.

17. Hollow cylindrical part (10) according to claim 13, wherein said at least one protuberance (12c) is an annular prism of essentially triangular section.

18. Hollow cylindrical part (10) according to any of claims 12-17, wherein the at least one protuberance (12a, 12b, 12c) has a thickness between 0.2 cm and 0.5 cm and a height of approximately between 0.4 cm and 0.8 cm.

19. Hollow cylindrical part (10) according to any of claims 12-18, which has a length between 3 cm and 8 cm.

20. Hollow cylindrical part (10) according to any of claims 12-19, which is made of an elastic material and comprises a longitudinal groove (3) configured to allow its opening to couple and disengage it from the endotracheal tube (100).