SUCH A MOUTHPIECE TECHNICAL FIELD OF THE INVENTION

This invention relates to a mouthpiece to be used during noninvasive ventilation (NIV) for both chronic and acute respiratory failure. This invention also relates to a kit which can be used for connecting an air supply apparatus to the mouth of the patient and which includes, amongst others, such a mouthpiece.

BACKGROUND OF THE INVENTION

Noninvasive ventilation has been used for several years in order to provide a patient with breathing air coming from an air supply system, such as a ventilator. A key issue for this kind of ventilation assistance is not to hurt the patient, while allowing him or her to breathe easily.

As mentioned by Luis BOITANO and Joshua BENDITT in their paper « An evaluation of home volume ventilators that support open-circuit mouthpiece ventilation » published in Respiratory Care (November 2005 - vol.50 - n ° 1 1 pages 1457-1461 noninvasive ventilation can be used to provide a portable daytime ventilator support for neuromuscular patients with chronic respiratory failure. The authors suggest to use a mouthpiece made of rigid plastic material and comprising two straight portions oriented at 45° one with respect to the other. On the other hard, the paper of Stefano NAVA, Paulo NAVALESI and Cesare GREGORETTI « Interfaces and humidification for noninvasive mechanical ventilation » published in Respiratory Care (January 2009 - Vol 54 - N ° 1 pages 71 to 84) considers several types of interfaces for noninvasive ventilation, including oral interfaces, nasal masks, pillows, oro-nasal and full-face masks and helmets. These equipments all have advantages and inconvenients. Mouthpieces which are held by the patients teeth and lips are rigid as shown on figure 2A of this paper. This can, in long-term use, cause orthodontic deformities. These rigid mouthpieces require to be precisely installed with respect to a wheel chair or to the patient, which is cumbersome and might lead to a loss of ventilation if the patient inadvertently or non-voluntarily moves the mouthpiece. Moreover, the patient cannot keep such a mouthpiece in its mouth when he or she wants to talk, which forces him or her to move his or her head backward and forward several times during a discussion.

On the other hand, US-A-2004/0221846 and US-A-2010/01 13956 disclose a nasal and cannula breathing detection device for monitoring breathing of a patient. Such a device includes a mouthpiece which is not designed to be used for non invasive ventilation.

SUMMARY OF THE INVENTION

The invention aims at solving this problem with a new noninvasive ventilation mouthpiece which is more comfortable for the patient than known mouthpieces and which can be kept in the mouth of the patient for a long period of time, without inducing orthodontic deformities.

To this end, the invention concerns a noninvasive ventilation mouthpiece comprising a first end, provided with connection means for connecting the mouthpiece to a gas supply system, a second end, to be placed in a patient's mouth during use of the mouthpiece, and a tubular body joining the first and second ends. According to the invention, the tubular body includes at least a flexible portion and the second end is adjustable in one or several directions with respect to the first end, via bending of the flexible portion.

Thanks to the invention, the actual geometry of the mouthpiece can be adapted to the morphology of the patient, to his or her habits and to the position of the gas supply system outlet with respect to the head of the patient. Since the second end of the tubular body is adjustable with respect to the first end, it is possible to bend the flexible portion in order to set the shape of the mouthpiece, in accordance to its actual conditions of use.

According to further aspects of the invention which are advantageous but not compulsory, the mouthpiece might incorporate one or several of the following features, taken in any technically admissible configuration:

- The flexible portion is made in PVC.

- The tubular body has a maximum outer transverse dimension between 5 and 10 mm and a maximum inner transverse dimension between 2 and 4 mm.

- The mouthpiece includes a bendable stiffening member which extends along the tubular body.

- The stiffening member is a metallic wire, preferably made of copper.

- The flexible portion extends continuously between the first end and the second end.

- The second end is equipped with a gas diffuser. This diffuser preferably includes a base crown adapted to be mounted on an end of the tubular body and several elastically deformable fingers which extends from the base crown along directions parallel to a central longitudinal axis of the diffuser. In such a case, it is possible that an axial length of the diffuser is between 15 and 20 mm and a maximum diameter of an envelope surface including respective outer surfaces of the fingers is smaller than 15 mm, preferably equal to 10 mm.

- The connection means include a connector provided with a socket, for accommodating an end of the tubular body, and a pipe portion adapted to be connected to a gas supply unit, the socket and the pipe portion being in permanent fluid communication.

- The tubular body has a length of less than 250 mm, preferably less than 200 mm, still preferably of about 150 mm. Alternatively, the tubular body has a length of more than 500 mm, preferably more than 800 mm, still preferably of about 1000 mm.

The invention also concerns a kit for connecting an air supply apparatus to the mouth of a patient, this kit comprising a noninvasive ventilation mouthpiece as mentioned here-above and fixation means for positioning the tubular body of this mouthpiece with respect to the patient and/or to a part in the vicinity of the patient.

Advantageously, the fixation means include at least one clamp. Alternatively or in addition, the fixation means include a harness to be worn by the patient and which defines at least a passage opening for the tubular body.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be better understood on the basis of the following description which is given in correspondence with the annexed figures and as an illustrative example, without restricting the object of the invention. In the annexed figures:

- figure 1 is an exploded perspective view of a mouthpiece according to the invention;

- figure 2 is a perspective view of the mouthpiece of figure 1 in use, in a first configuration;

- figure 3 is an enlarged cut view along a plane III on figure 2;

- figure 4 is perspective view similar to figure 2 when the mouthpiece is in a second configuration of use;

- figure 5 is an enlarged perspective view of an air diffuser of the mouthpiece of figure 1 and

- figure 6 is a front view of the diffuser of figure 5.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

The noninvasive ventilation mouthpiece 10 represented on the figures includes a single connector 12 which forms a first end of the mouthpiece, a single diffuser or tip member 14 which forms a second end of the mouthpiece and a single flexible tube or tubular body 16 which connects the connector 12 to the diffuser 14.

Connector 12 includes a base plate 122, a socket 124 and a sleeve 126 forming a pipe portion. Sleeve 126 is used to connect mouthpiece 10 to a source of air under pressure, such as a ventilator 20. The external diameter of sleeve 126, which has a cylindrical cross-section, is adapted to the internal dimensions of an outlet of a non represented circuit of ventilator 20. Socket 124 also has a cylindrical cross-section and d124 denotes its internal diameter. A through hole extends through base plate 122 and permanently connects the inside volume of socket 124 and the inside volume of sleeve 126. Connector 12 is made of a single piece of plastic material, such as polyethylene. X12 denotes a central axis of connector 12.

Diffuser 14 is made of a single piece of a soft material such as silicone or a natural or synthetic elastomer. Diffuser 14 includes a crown 142 and six fingers 144 regularly distributed around a central axis X14 of diffuser 14. Fingers 144 are parallel to axis X14 and extend from crown 142 along directions parallel to axis X14. Notches 146 are defined between the fingers 144. The geometry and the material of diffuser 14 allow fingers 144 to elastically deform when they are bitten by a patient or when they come into contact with the teeth, the tongue or the cheeks inside the mouth of a patient. Because of its deformability, diffuser 14 can be kept in the mouth of a patient for a long period of time.

L14 denotes the axial length of diffuser 14, that is its length along axis X14. Length

L14 is chosen between 15 and 20 mm. Diffuser 14 has a shape centered on axis X14 and D14 denotes the maximum diameter of an envelope surface S14 which includes the respective outer surfaces of fingers 144. Diameter D14 is the maximum transverse dimension of diffuser 14. Its value is chosen smaller than 15 mm, preferably equal to 10 mm.

According to a non represented embodiment of the invention, diffuser 14 can have an oval transverse shape or a so called « flat » shape. In such a case, the maximum transverse dimension of diffuser 14 is also chosen less than 15 mm, preferably equal to 10 mm.

Tube 16 can be qualified as a "straw". It extends along a central axis X16 between a first end 162 and a second end 164 which are respectively introduced within socket 124 of connector 12 and within crown 142 of diffuser 14. A shown on figure 3, tube 16 has a globally circular cross-section with a lateral extension 166. The circular portion of tube 16 has an outer diameter D16 which has a value equal to the value of diameter d124. Thus, the first end 162 of tube 16 can be tightly fitted within socket 124, thanks to a localized deformation of socket 124, in order to accommodate extension 166. Similarly, the internal diameter of crown 142 is adapted to accommodate the second end 164 of tube 16, thanks to a localized deformation.

A copper wire 168 extends along tube 16, within extension 166. Thus, wire 168 is accessible neither from outside tube 16 nor from the internal volume V16 of this tube.

Tube 16 is made of a synthetic flexible material, namely PVC or polyvinyl chloride.

Alternatively, tube 16 can also be made of any plastic material suitable for medical use.

W16 denotes the maximum width of tube 16, which is taken at the level of extension 166. Width W16 is larger than diameter D16. In practice, width W16 is between 5 and 10 mm, whereas diameter D16 is between 4 and 8 mm. Volume V16 has a cylindrical cross- section and d16 denotes the internal diameter of tube 16. Diameter d16 has a value between 2 and 4 mm.

Depending on the size of the patent's mouth, the diameters D16 and d16 and the width W16 can be increased respectively up to 15 mm, 1 1 mm and 18 mm.

The provision of wire 168 gives some stiffness to tube 16, so that this tube can be shaped according to the needs, in particular according to the morphology of the patient and/or to the location of the ventilator with respect to the patient's head.

The length L16 of the tube 16 is chosen with a value of less than 250 mm, preferably less than 200 mm. Some good results can be obtained with a tube of 150 mm in length. In such a case, the ventilator 20 is located in the vicinity of the patient's head and the tube 16 can extend freely between the connector 12 and the mouth of the patient. A shown by the comparison of figures 2 and 4, tube 16 can be bended in different directions in order take into account the actual location of ventilator 20 and to place diffuser 14 in the mouth of the patient, without hurting the patient and/or deforming his/her teeth. Since tube 16 is flexible, it is easy for the patient or for a medical staff to shape tube 16 to the actual needs. Once tube 16 has been shaped according to the needs, wire 168 keeps tube 16 in the desired configuration.

Actually, the diameter d16 and length L16 of tube 16 can be chosen on the basis of the patients' morphology and handicap. In other words, selecting a tube 16 with given diameter and length allows adapting mouthpiece 10 to the patient, in particular to his/her potential orthopedic deformities.

Axis X16 is curved in the configurations of figures 2 and 4. Axis X12 and X16 are superimposed at the level of first end 162, whereas axis X14 and X16 are superimposed at the level of second end 164. A shown by the comparison of figures 2 and 4, the position of axis X14 can be adjusted with respect to axis X12 by proper bending and shaping of tube 16 along several directions, as shown by arrows F1 and F2, which represent some bending possibilities of tube 16. An angle a defined between axes X12 and X14 changes its value from about 90 ° in the configuration of figure 2 to about 135° in theconfiguration of figure 4. Actually, angle a can take any value between about 30° and 180° .

The orientation of diffuser 14 with respect to axis X12 can also be changed by a rotation of first end 162 within socket 124.

The invention is represented on figures 2 and 4 when tube 16 has a single concavity. However tube 16 can be shaped with an inflexion point, e.g. with an S shape.

According to a non-represented alternative embodiment of the invention, the length L16 of tube 16 can be larger than 500 mm, preferably larger than 800 mm. Good results can be obtained with a tube of 1 m in length. This is appropriate when ventilator 20 is located, for instance, on the back of a wheel chair. Under such circumstances, a path must be defined between the ventilator and the mouth of the patient and some non represented fixation means are used for positioning the tube 16 with respect to the patient and/or with respect to a part in its vicinity, for instance the back rest or an arm rest of the wheel chair. To this end, some clamps can be used to immobilize the tube 16 with respect to the wheel chair or to the cloths of the patient.

Alternatively, the patient can wear a non represented harness which defines one or several passage openings for the tube 16, so that this tube is guided along the patient's body from ventilator 20 to the mouth of the patient. Since tube 16 is flexible, it can be shaped to follow the prescribed path, along the patient's body or along the wheel chair and it will substantially keep the desired configuration thanks to the stiffening effect obtained by the wire 168. On the other hand, since tube 16 is flexible, it cannot hurt the patient even if it is located close to its body.

Clamps and harness can also be used together and/or with a mouthpiece including a relatively short tube, like the one represented on the figures.

Irrespective of the actual length of the tube 16, the mouthpiece 10 of the invention can be used for a long period of time, e.g. between eight and sixteen hours, during day time and it is compatible with some movements of the patient's head, with speech and possibly with feeding. In other words, thanks to the flexibility and to the stiffness of tube 16, and thanks to the deformability of diffuser 14, the diffuser can be kept in the patient's mouth for a long period of time, even during speech and feeding. When he or she wants to swallow or talk, the patient can easily move diffuser 14 within his or her mouth, thanks to the flexibility of tube 16.

According to alternative embodiments of the invention, a connector different from connector 12 can be used, provided that it allows to feed tube 16 with air at a desired pressure. Alternatively, no connector is used and the first end 162 of tube 16 is directly plugged onto an outlet opening of ventilator 20, provided that this outlet has a shape adapted to this purpose.

The actual shape and material of diffuser 14 can be changed, provided that it remains compatible with a long stay in the mouth of the patient.

According to a non represented alternative embodiment of the invention, another source of air under pressure can be used, instead of ventilator 20. The invention is compatible with an "active" system where the patient sucks air from mouthpiece 10 when needed. It is also compatible with a « passive » system where air is continuously provided, which is the case with ventilator 20.

Alternatively, a gas different from air can be provided with via mouthpiece 10.

In the example of the figures, tube 16 is flexible and extends continuously between connector 12 and diffuser 14. Alternatively, only a part of tube 16 can be flexible. This is in particular useful when the length L16 of tube 16 is important, e.g. larger than 500 mm.

According to an alternative embodiment of the invention, the stiffening member of tube 16 could be a made in a metal different from copper or in a non metallic material, such as a semi-rigid plastic material or carbon.

The embodiments and variants mentioned here-above can be combined in order to generate other embodiments of the invention.