Abstract:
A device for artificial respiration, including a front support ( 3 ) which is connected to a respiratory mask ( 1 ) that includes a connection for the respiratory tube ( 4 ), a front support is coupled to the respiratory mask by a distancing element ( 2 ) and at least one cavity ( 11 ) is arranged in the region of the distancing element, the cavity leading into an inner chamber ( 12 ).

Description:
BACKGROUND OF THE INVENTION 
     The invention concerns a ventilator, which has a forehead support connected with a ventilator mask, where the ventilator mask is provided with a connection for a ventilator hose, and where the forehead support is coupled with the ventilator mask by a spacing element. 
     A typical use of devices of this type is in connection with respiratory air supply systems used in CPAP therapy (CPAP=continuous positive airway pressure). They can also be used in bilevel ventilation, APAP ventilation, home ventilation, and hospital emergency ventilation. 
     Typically, an expiratory element, which diverts the patient&#39;s exhaled respiratory gas to the environment, is installed in the area of the ventilator hose just in front of the connection of the ventilator hose with the ventilator mask. Especially when the ventilator mask is used during nighttime hours, previously known expiratory elements still cannot meet all requirements with respect to comfort of use. When the patient is in a reclining position, the expiratory elements are often positioned in front of his throat or chest, which causes the air to flow towards the patient. This kind of air flow causes cooling and possibly drying of the skin exposed to the air flow. Therefore, the patients catch cold relatively often unless suitable countermeasures are taken, but patients also often find these countermeasures unpleasant. 
     SUMMARY OF THE INVENTION 
     The objective of the present invention is to design a device of the aforementioned type in such a way that exhaled air does not flow in the patient&#39;s direction. 
     In accordance with the invention, this objective is achieved by providing the spacing element with at least one cavity, which opens into an interior space of the ventilator mask. 
     By designing the spacing element with a cavity, it is possible to divert the respiratory gas exhaled by the patient in such a way that the gas does not flow against the patient&#39;s throat or chest. User comfort can be greatly improved in this way, and the risk of colds can be reduced. 
     The discharge of respiratory gas in the vicinity of the forehead support is assisted if the cavity opens into an interior space of the forehead support. 
     A possibility for the discharge of the respiratory gas consists in the fact that the spacing element has at least one discharge opening. 
     In particular, it is advantageous if the discharge opening faces away from the patient. 
     In another design variant, the forehead support is provided with at least one discharge opening. 
     When the respiratory gas is discharged through the forehead support, it is also advantageous for the discharge opening to face away from the patient. 
     Optimum elimination of carbon dioxide from the respiratory gas is supported by providing at least certain areas of the ventilator mask with a double-walled construction. 
     To support favorable flow guidance, it is provided that the body of the ventilator mask and an inner shell together bound a flow channel that opens into the cavity. 
     It is also conducive to uniform flow guidance for a coupling part for the ventilator hose to extend through the flow channel into the region of the interior space of the ventilator mask. 
     To guarantee that an intended ventilation pressure is maintained, it is proposed that an adjustable baffle be installed in the area of at least one of the discharge openings to produce a discharge resistance that can be preset. 
     Simple manipulation of the baffle can be realized with a sliding baffle. 
     The use of a rotatable baffle has also been found to be advantageous. 
     In another design variant, a membrane element is installed in the area of at least one of the discharge openings. 
     In addition, it is proposed that a slotted silicone insert be installed in the area of at least one of the discharge openings. 
     Discharge of exhaled respiratory gas as a function of the given position of the ventilator mask or the patient can be realized by installing a movable closure element in the area of at least one of the discharge openings. 
     In particular, it has been found to be advantageous for the closure element to be installed in a way that allows its position to be varied. 
     Position-dependent positioning of the closure element can be realized in a simple way by designing the closure element as a ball. 
     In accordance with another embodiment, the closure element is designed as a baffle. 
     To ensure that a predetermined therapeutic pressure is maintained, at least one throttle element can be installed in the spacing element to control the flow resistance. 
     Another possible means of directing the flow of respiratory gas is the installation of a movable discharge nozzle in the vicinity of at least one discharge opening. 
     Modular adaptability to different practical requirements can be realized through the use of interchangeable throttle modules in the spacing element. 
     In accordance with a simplified embodiment, it is proposed that the ventilator mask have at least one discharge opening that faces away from the patient. 
     The discharge of exhaled respiratory gas away from the patient is promoted by the discharge of the respiratory gas with the use of an expiratory hose. 
     A compact design can be realized by arranging the cavity inside the spacing element. 
     A modular system design can be realized if the cavity is located in a flow guide element outside the spacing element. 
     If the ventilator mask consists of at least two detachably connected components, this also contributes to simple configurability. 
     Assembly and disassembly operations are assisted if the two or more components are connected with one another by a manually releasable locking mechanism. 
     Well-defined flow paths for avoiding a constriction of respiratory gas flowing in and respiratory gas flowing out can be realized if at least one of the components is hollow and is designed for removing exhaled air. 
     In addition, the production of well-defined flow paths is supported by the use of a ventilator mask that preferably consists of at least three detachably connected components, of which at least two components are connected with one another by a manually releasable locking mechanism, and one of the components is designed for removing exhaled air, and the other component is designed for supplying fresh respiratory gas. 
     Separate flow paths are also realized if at least two of the components have an internal cavity, and one of the components is designed basically for removing exhaled air, and the other component is designed basically for supplying fresh respiratory gas. 
     Furthermore, it is proposed that at least two of the components have an internal cavity and that in at least one operating state, a higher average concentration of carbon dioxide be present in one of the hollow components than in the area of the other component. 
     A general design principle for realizing separate flow paths is described by a ventilator mask which has at least three interconnected openings and in which at least one of the openings opens into a cavity, and at least one of the openings is designed basically for removing exhaled air, and the other opening is designed basically for supplying fresh respiratory gas. 
     In a typical design, at least one of the openings opens into a cavity, and this opening is designed basically for removing exhaled air in a direction radially away from the body of the mask, and the other opening is designed basically for supplying fresh respiratory gas. 
     It is also proposed that at least one of the openings have an internal cavity, and that this opening be designed essentially for removing exhaled air above the eye level of the patient, while the other opening be designed essentially for supplying fresh respiratory gas. 
     Comfort of use is further enhanced if at least one of the openings opens into a cavity, and this opening is designed basically for discharging exhaled air to a point far from the patient&#39;s face, while the other opening is designed basically for supplying fresh respiratory gas. 
     In addition, it is proposed that a discharge channel for creating an exhalation system extend along at least certain parts of the forehead support. 
     Discharge of respiratory gas in a direction away from the patient can also be realized by providing a flow path into the ventilator mask for an air flow coming from a compressed gas source and by providing a discharge channel for discharging the exhaled air, such that the discharge channel extends at an angle of 45° to 135° relative to a plane that is defined by the perpendicular of the inlet for the respiratory gas supply. 
     In addition, it has been found to be advantageous in a general way for a cavity located in the forehead support to be connected by at least one connecting passage with an interior space of the ventilator mask and at least one discharge opening. 
     Specific embodiments of the invention are illustrated in the accompanying schematic drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
         FIG. 1  shows a longitudinal section through a ventilator mask with a forehead support. The mask is positioned on the patient&#39;s head, and respiratory gas is discharged through the forehead support. 
         FIG. 2  shows a perspective view of a ventilator mask with a forehead support and adjustable discharge openings in the area of a spacing element of the forehead support. 
         FIG. 3  shows a cross section through the spacing element of the forehead support. 
         FIG. 4  shows a partial view of the forehead support in viewing direction IV in  FIG. 2 . 
         FIG. 5  shows an embodiment that employs membrane inserts. 
         FIG. 6  shows an embodiment that employs slotted silicone inserts. 
         FIG. 7  shows an embodiment with adjustable discharge openings. 
         FIG. 8  shows a ventilator mask with a discharge opening for the elimination of carbon dioxide. 
         FIG. 9  shows a side view in viewing direction IX in  FIG. 8 . 
         FIG. 10  shows another embodiment with a discharge opening in the ventilator mask, in which a discharge hose is placed on a discharge connector. 
         FIG. 11  shows a side view in viewing direction XI in  FIG. 10 . 
         FIG. 12  shows an embodiment with an adjustable discharge opening, in which positionable closure elements are located near the discharge openings. 
         FIG. 13  shows a partially cutaway side view of the embodiment according to  FIG. 12 . 
         FIG. 14  shows an embodiment with an adjustable closure, in which a baffle that can be set in a desired position is used as the closure element. 
         FIG. 15  shows a modification of the embodiment in  FIG. 14  with the use of a movable ball. 
         FIG. 16  shows an embodiment with a throttle element in the spacing element to help maintain an internal pressure in the ventilator mask. 
         FIG. 17  shows a side view in viewing direction XVII in  FIG. 16 . 
         FIG. 18  shows an embodiment with swiveling discharge nozzles. 
         FIG. 19  shows a side view in viewing direction XIX in  FIG. 18 . 
         FIG. 20  shows an embodiment with replaceable throttle elements in the spacing element. 
         FIG. 21  shows a side view in viewing direction XXI in  FIG. 20 . 
         FIG. 22  shows a longitudinal section through a throttle element that is a modification of the throttle element shown in  FIG. 20  and has a sinuous flow path. 
         FIG. 23  is a drawing of another modified throttle element. 
         FIG. 24  is a drawing of another throttle element, which consists of porous material. 
         FIG. 25  shows an embodiment that employs another modified throttle element with longitudinal channels. 
         FIG. 26  shows another modification of the throttle element. 
         FIG. 27  shows a further modification of the throttle element with a double channel. 
         FIG. 28  shows another embodiment of the throttle element with a nozzle-like channel. 
         FIG. 29  shows another embodiment of the throttle element. 
         FIG. 30  shows a throttle element in which sintered material is used. 
         FIG. 31  is a schematic drawing of a ventilator mask with forehead support and spacing element, with the throttle element shown removed from the spacing element. 
         FIG. 32  is a drawing similar to  FIG. 31 , with the throttle element shown partially inserted. 
         FIG. 33  is a drawing that corresponds to  FIG. 31  and  FIG. 32 , with the throttle element shown completely inserted. 
         FIG. 34  shows an embodiment that is modified relative to the embodiment in  FIG. 1 , with flow occurring essentially entirely through the double shell of the ventilator mask. 
         FIG. 35  shows an embodiment that is modified relative to the embodiment in  FIG. 13 , with a chimney-like discharge element. 
         FIG. 36  shows an embodiment that is further modified relative to the embodiment in  FIG. 35 , with discharge of respiratory gas through both a chimney-like element and through the base of the forehead support. 
         FIG. 37  is a view as in  FIG. 20 , of an embodiment with a locking mechanism. 
         FIG. 38  is a view as in  FIG. 34 , of an embodiment with a discharge channel. 
         FIG. 39  is a view as in  FIG. 36 , of an embodiment with an external flow guide element. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       FIG. 1  shows an embodiment in which a ventilator mask  1  is coupled with a forehead support  3  by a spacing element  2 . A ventilator hose  4  opens into the ventilator mask  1 . 
     The ventilator mask  1  consists of a mask body  5  made of a strong material and a sealing element  6 , which rests against the face of a patient  7  and is connected by a profile  8  with a mating profile  9  of the body  5  of the mask. 
     The spacing element  2  has an outer wall  10  that bounds a cavity  11 , which opens into an interior space  12  of the ventilator mask  1 . In the embodiment shown in  FIG. 1 , the cavity  11  opens into an interior space  13  of the forehead support in its expanded area facing away from the ventilator mask  1 . The forehead support  3  consists essentially of a body  14  and a cushion  15 . 
     The ventilator hose  4  is preferably rotatably supported in the body  5  of the mask. In the embodiment of  FIG. 1 , the body  5  of the mask is equipped with an inner shell  16 , which provides a double-walled construction. A flow channel  17  extends between the inner shell  16  and the mask body  5  and is connected with the interior space  12  of the ventilator mask  1  by at least one opening  18  in the inner shell  16 . The opening  18  is preferably located near the nostrils  19  of the patient  7 . 
     Furthermore, the flow channel  17  is arranged in such a way that it ends in the vicinity of the opening of the cavity  11  into the interior space  12  of the ventilator mask  1 . In this way, the respiratory gas exhaled by the patient is carried through the opening  18  and the flow channel  17  and into the area of the cavity  11 . This design largely prevents any mixing of fresh respiratory gas from the ventilator hose  4  and exhaled respiratory gas. Ventilation effectiveness can be increased in this way. 
     The spacing element  2  has an angled design in the embodiment according to  FIG. 1 . A base segment  20  extends essentially vertically, and an end segment  21  extends more or less perpendicularly to the base segment  20  in the direction of the forehead  22  of the patient  7 . The body  14  of the forehead support  3  has a mounting device  23  that fits into the end segment  21  and allows transverse positioning of the forehead support  3  relative to the spacing element  2 . 
     The principal flow directions of the respiratory gas are indicated in  FIG. 1  by flow arrows. In particular, the drawing shows that a large portion of the exhaled respiratory gas is discharged from the forehead support  3  in a direction away from the patient  7 . Optimum discharge of the respiratory gas can be achieved by suitable predetermination of the discharge openings in the area of the forehead support  3 . 
       FIG. 2  shows an embodiment in which discharge openings  24  are placed in the area of the spacing element  2 . The discharge openings  24  can be at least partially covered by a baffle  25 , which is installed in such a way that it can be positioned by an adjusting element  26 . By adjusting the baffle  25 , a suitable discharge resistance can be preset to prevent gas from flowing directly from the ventilator hose  4  to the discharge openings  24 . The baffle  25  thus ensures that the required ventilation pressure can develop in the ventilator mask  1 . The adjusting element  26  can be designed, for example, as a slide that can be positioned along a groove  27 . Adequate positioning reliability can be provided by catches  28 . 
     The embodiment in  FIG. 2  also provides for the placement of discharge openings  29  in the area of the cushion  15  of the forehead support  3 . In the embodiment according to  FIG. 2 , discharge openings  30  are also provided in the area of the body  14  of the forehead support  13 . 
     In the embodiment according to  FIG. 2 , additional discharge openings  32  of the forehead support  3  are located in an upper region of the body  14 , and the size of the discharge openings  32  can be preset by closure elements  31  that can be turned. 
       FIG. 3  shows a cross section through the spacing element  2 . It is apparent that the displaceable baffle  25  is located in a region of transition from the cavity  11  into the discharge openings  24 . 
       FIG. 4  is a side view that again shows the location of the discharge openings  30 ,  32  in the area of the forehead support  3  and the positioning of the closure elements  31 . It is apparent that the corresponding discharge openings  32  can be placed at both the top and the bottom of the forehead support  3 . 
       FIG. 5  shows an embodiment in which membrane elements  33  are arranged in the area of the discharge openings  24  of the spacing element  2  to produce a suitable discharge resistance. The membranes can also be provided with moisture-retaining properties to prevent increased drying out of the patient by the ventilation. Similar membrane elements  33  can also be placed in the area of the discharge openings  29 ,  30 ,  32  of the forehead support  3 . 
     In the embodiment in  FIG. 6 , slotted silicone inserts  34  are placed in the area of the cushion  15  to provide discharge openings  29 . The silicone inserts  34  can be placed both at the top and the bottom of the forehead support  3 . 
     In the embodiment in  FIG. 7 , at least one discharge opening  30  that can be closed to a predeterminable extent by a baffle  35  is located in the area of the forehead support  3 . The baffle  35  can be rotated by means of an operating element  36  and provides an adjustable state of opening of the discharge opening  30 . The baffle  35  can be provided, for example, with holes, slots, or adjustable expiratory flaps. 
       FIG. 8  shows an embodiment that can be used for optimum discharge of exhaled respiratory gas without the use of a forehead support  3 . To this end, in its operating state, the ventilator mask  1  has a discharge opening  38  above a coupling part  37  for the ventilator hose, which is not shown in  FIG. 8 . The discharge opening  38  conducts the exhaled respiratory gas in a direction away from the patient. 
       FIG. 9  illustrates that the discharge opening  38  is preferably located in a flattened region of the ventilator mask  1 . Respiratory gas is supplied exclusively through the coupling part  37  and is discharged through the discharge opening  38 . This has been found to provide optimum elimination of carbon dioxide. 
     The embodiment according to  FIG. 10  and  FIG. 11  is functionally similar to the embodiment in  FIGS. 8 and 9 . However, instead of a simple discharge opening  38 , this embodiment has a discharge connector  39 , to which an expiratory hose  40  is connected. The use of the expiratory hose  40  makes it possible for the exhaled respiratory air to be discharged at almost any desired predetermined point, so that patient comfort can be optimized in this respect. 
       FIG. 12  shows an embodiment in which at least one group of discharge openings  41 ,  42 , which consists of at least two individual discharge openings  41 ,  42 , is located in the area of the forehead support  3 . The discharge openings  41 ,  42  can be closed by at least one closure element  43 , which automatically assumes a certain position, depending on the given spatial position of the patient  7 . Depending on the given position of the patient  7 , it is thus predetermined that one or more of the discharge openings  41 ,  42  are closed or open. This makes it possible to open or close different discharge openings  41 ,  42  when the patient  7  is lying, for example, on his left side, than when he is lying on his right side. It is also possible, depending on whether the patient  7  is in an upright or reclining position, to discharge the respiratory gas through the discharge openings  41 ,  42  that are the optimum discharge openings under the given current conditions. 
       FIG. 13  shows a partially cutaway side view of the embodiment according to  FIG. 12 . The exhaled respiratory gas is again fed in the direction of the discharge openings  41 ,  42  through the cavity  11  of the spacing element  2 . 
       FIG. 14  shows an embodiment for realizing the closure element  43  with the use of a movable baffle. Depending on the given spatial position of the forehead support  3 , the baffle is open or closed. 
       FIG. 15  shows an embodiment in which the closure element  43  is a movable ball that is arranged in such a way that, depending on the given position of the forehead support  3 , one or the other of the discharge openings  41 ,  42  is closed or neither of the discharge openings  41 ,  42  is closed. 
       FIG. 16  shows an embodiment in which a throttle element  44  is installed in the spacing element  2 . The throttle element  44  produces a well-defined discharge resistance for the exhaled respiratory gas and guarantees that a sufficient ventilation pressure can develop in the ventilator mask  1 . In the embodiment illustrated in  FIG. 16 , the throttle element  44  consists of a plurality of lips arranged one behind the other, which separate individual chambers  45  from each other. The chambers  45  are connected with each other only by individual overflow openings  46 . In addition to helping produce the necessary ventilation pressure, this arrangement can also improve the level of sound damping. 
     The partially cutaway side view in  FIG. 17  shows that, in the embodiment according to  FIG. 16 , it is also possible to use a double-walled construction with an inner shell  10 . In principle, it is possible to use this double-walled construction, which helps achieve optimum elimination of carbon dioxide, in all of the design variants explained here. 
       FIG. 18  shows an embodiment in which movable discharge nozzles  47  are used. The discharge nozzles  47  are installed in the forehead support  3  in a way that allows them to swivel or slide. A desired direction of discharge of the respiratory gas can be preset by moving the discharge nozzles  47  into the corresponding position. For example, when the patient is in the supine position, it is possible to set the discharge nozzles  47  to discharge the respiratory gas directly upward. When the patient is lying on his right side, the discharge nozzles  47  and their openings are turned to the left, and when he is lying on his left side, the discharge nozzles  47  and their openings are turned to the right. 
       FIG. 19  shows a side view of the embodiment according to  FIG. 18 . It is also apparent here that exhaled respiratory gas is fed to the discharge nozzles  47  through the cavity  11  of the spacing element  2 . 
     In the embodiment in  FIG. 20 , the throttle element  44  according to  FIG. 16  is installed in the spacing element  2  as a removable throttle module  48 . This makes it possible to supply a variety of different throttle modules  48 , which are inserted in the spacing element  2  according to the individual practical requirements of each case. 
       FIG. 21  shows a side view of the ventilator mask  1  with forehead support  3 , in which a replaceable throttle module  48  is positioned in the spacing element  2 . 
       FIG. 22  shows a design of the throttle module  48 , in which a flow path  49  is bounded in such a way by shaped sidewalls that a cross-sectional area that varies in the direction of flow  50  is realized. 
       FIG. 23  shows an embodiment in which the flow in the throttle module  48  follows a winding path  49  with a variable cross-sectional area. In the embodiment in  FIG. 24 , the throttle module  48  has an insert that consists of a porous material with an internal porosity of up to 4,500 m 2 /g. 
       FIG. 25  shows an embodiment in which the throttle module  48  is designed as a replaceable insert, which, for example, is adapted to specific pressure stages. For example, it is possible to use one insert for a pressure stage of 4-6 mbars, another insert for a pressure range of 6-8 mbars, and other inserts for other pressure stages. The design of the individual throttle modules  48  can be adapted within wide limits to a given practical requirement. 
       FIG. 26  shows an embodiment in which the throttle module  48  has a smaller number of flow paths  49  than the throttle module  48  shown in  FIG. 25 , although the flow paths  49  have larger cross-sectional areas than those in the embodiment of  FIG. 25 . 
     In the embodiment shown in  FIG. 27 , several flow paths  49  with a curved path similar to a serpentine curve extend through the throttle module  48 . 
     In the embodiment shown in  FIG. 28 , the throttle module  48  has a flow path  49  shaped like a nozzle module, with the nozzle cross section first constricting and then expanding in the direction of flow. 
     In the embodiment shown in  FIG. 29 , the flow path  49  follows a course with abrupt changes in cross-sectional area, in which a contour pattern is provided that is similar in shape to the outline of a Christmas tree. The embodiment according to  FIG. 30  shows another realization of the throttle module  48  with the use of a porous material, for example, a sintered material. 
       FIG. 31  is a schematic illustration of a throttle module  48  removed from the spacing element  2 . In the embodiment shown in  FIG. 32 , the throttle module  48  was partially inserted in the spacing element  2 . The drawing in  FIG. 33  shows the throttle module  48  in its final position in the spacing element  2 . In particular, it is proposed that the proper insertion of the throttle module  48  in the spacing element  42  be indicated by the generation of an acoustic signal. For example, it is possible, to use locking elements, which produce a clicking sound when the throttle module  48  is fully inserted. The throttle module  48  can be fixed in the spacing element  2  by spring elements, which can be released, for example, by manually squeezing the spring elements. 
     In the embodiment in  FIG. 34 , which is a modification of the embodiment in  FIG. 1 , no passage to the interior space  12  of the ventilator mask  1  is provided vertically below the cavity  11 , but rather the entire amount of air exhaled by the patient  7  flows through the opening  18  and into the flow channel  17  between the body  5  of the mask and the inner shell  16 . This design further improves the separation of the flow paths for the respiratory gas introduced through the ventilator hose  4  and the respiratory gas exhaled by the patient and prevents thorough mixing of the fresh respiratory gas and the used respiratory gas. This can enhance the effectiveness of the ventilation and reduce the amount of fresh respiratory gas that needs to be supplied. 
       FIG. 35  shows a further modified embodiment. In this case, the cavity  11  is not connected with discharge openings in the vicinity of the body  14  of the forehead support  3 , but rather the cavity  11  opens into a discharge element  52  that is located basically at a height level above the forehead support  3 . The discharge element  52  can be designed, for example, in the form of a connector or a hose. Additional discharge openings  53  can be placed in the spacing element  2 . 
       FIG. 36  shows an embodiment that is further modified relative to the embodiment in  FIG. 35 , in which respiratory gas is discharged not only through the chimney-like discharge element  52  but also through the body  14  of the forehead support  3  or the cushion  15  of the forehead support  3 . This further increases the discharge area and thus reduces discharge velocities and discharge sounds. 
     In most of the illustrated embodiments, respiratory gas is discharged from the area of the ventilator mask  1  via a cavity  11  inside the spacing element  2 . In principle, it is also possible to place the cavity  11  outside the spacing element  2  but immediately adjacent to the spacing element  2 . For example, a hose or other suitable hollow component for conveying the exhaled respiratory gas to the vicinity of the discharge opening provided for this purpose can be arranged parallel to the spacing element  2 .