Patent Publication Number: US-6659100-B2

Title: Sealed back pressure breathing device

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of my application Ser. No. 09/699,226 filed on Oct. 26, 2000 for “Sealed Back Pressure Breathing Device,” now U.S. Pat. No. 6,510,846 which is a continuation-in-part of my joint application Ser. No. 09/471,553, filed on Dec. 23, 1999, entitled “Sealed Back Pressure Attachment Device for Nebulizer,” now U.S. Pat. No. 6,412,481, the full disclosures of which are incorporated by reference herein. 
    
    
     BACKGROUND OF INVENTION 
     The present invention relates to a device for assisting pulmonary functions of a patient; it can be used alone for exercising muscles involved in breathing or in combination with a nebulizer for delivery of medication to the airways of a patient. More particularly, the present invention relates to a breathing device for generating positive backpressure in the airways of the user so as to keep the airways open and restore normal breathing. 
     Nebulizers are some of the most widely used devices for assisting patients with breathing problems; they help deliver medication during asthma attacks, emphysema attacks and similar occasions. Nebulizers are conventionally used in emergency rooms, by patients, and medical professionals when conventional method metered dose inhalers (MDIs) fail to reverse a constriction in the airways. The nebulizers break down the liquid medicine into tiny droplets that resemble mist and then deliver the medication into the lungs and airways of the patient. 
     Conventionally, nebulizers dispense airway dilators. For example, when a patient is brought into an emergency room, he has an unusually high concentration of carbon dioxide in blood. The nebulizer helps deliver the much-needed dilators to the lungs and help expel the gas from the lungs. The dilators contain a chemical that reacts with the receptors in the bronchioles of the patient to open the airways. The medications may include steroids, magnesium sulfate, and bronchodilators. 
     However, conventional nebulizers are relatively slow, it may require up to eight hours of treatment. When a patient arrives in an acute condition that requires an immediate treatment, an ambu bag with a mask is often used. The mask seals the mouth and nose of the patient; when the bag is squeezed positive pressure forces the medication into the airways. This procedure is not free from complications. Air may be diverted into the patient&#39;s stomach and cause gastric distention or vomiting, which in turn increases the risk of aspiration since the vomited medium may be inhaled and forced into the lungs. 
     Some patients cannot be helped with either nebulizers or ambu bags; they require a ventilator, an artificial breathing machine that works with an endotracheal tube inserted into the trachea of the patient. The positive pressure is much greater than when nebulizer with an ambu bag are used. Often times, excessive air is forced into the patient&#39;s lungs. The longer a patient stays on a ventilator, the more difficult it may be to wean the patient from ventilator. Prolonged use of the ventilator tends to cause atrophy of inspiratory muscles, which may become irreversible. 
     This invention contemplates elimination of drawbacks associated with the prior art and provision of hand-held devices that can be equally used by the patient and by a medical professional for exercising inspiratory muscles and for delivery of medication with the help of a nebulizer. 
     SUMMARY OF THE INVENTION 
     It is, therefore, an object of the present invention to provide a sealed calibrated back pressure device that would allow creation of positive pressure on the constricted airways of a patient suffering from asthma, emphysema or other respiratory diseases. 
     It is another object of the present invention to provide a sealed back pressure breathing attachment device for a nebulizer that can be preset to create the desired amount of pressure and deliver the medication for restoring the patient&#39;s breathing. 
     It is a further object of the present invention to provide a breathing device that would help in exercising inspiratory muscles of a patient. 
     These and other objects of the present invention are achieved through a provision of a hand-held lightweight device that has a means for adjusting the amount of positive pressure created in the airways of the patient. The device has a hollow body with a peep valve mounted on a bracket inside the hollow body. The hollow body is provided with two through openings: an intake port and an exhalation port. An intake valve, which can be as simple as a rubber gasket, is mounted in the hollow body between the exhalation valve and an open end. 
     The open end may carry a mouthpiece or be suitably sized and shaped to be connected, via a manifold, to a nebulizer. The opposite closed end of the hollow body carries a means for adjusting the positive pressure. In one of the embodiments, the adjustment means is a cap that threadably engages the hollow body; in the second embodiment—it is an adjustable cam lever. A compression spring is mounted between the exhalation valve and the adjustment means. The calibration may be set to a desired pressure, preferably between 5 cm and 20 cm of water. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     Reference will now be made to the drawings, wherein like parts are designated by like numerals, and wherein 
     FIG. 1 is a perspective view of the attachment device in accordance with the first embodiment of the present invention. 
     FIG. 2 is a longitudinal sectional view of the device shown in FIG. 1 showing the adjustable cap threadably engaged with the main body. 
     FIG. 3 is a longitudinal sectional view of the device of the first embodiment, with the adjustable cap being separated from the main body. 
     FIG. 4 is a perspective view of the second embodiment of the device in accordance with the present invention mounted on a manifold that connects the device to a nebulizer. 
     FIG. 5 is a longitudinal sectional view showing the embodiment of FIG. 4 with an adjustable cam lever. 
     FIG. 6 is a longitudinal sectional view of the second embodiment showing air movement on inspiration and expiration. 
     FIG. 7 is a detail view showing a support bracket on the expiration valve. 
     FIG. 8 is a detail front view showing the intake open on the exhalation valve. 
     FIG. 9 is a detail view showing an intake valve. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Turning now to the drawings in more detail, numeral  10  designates the device in accordance with the first embodiment of the present invention. The device  10  comprises an elongated main hollow body  12  having a first cylindrical portion  14 , a unitary connected middle conical portion  16 , and a mouthpiece  18 , which is unitary connected to the middle portion  16 . A central opening  20  is formed in the body  12 , extending from the mouthpiece opening  22 , through the mouthpiece  18 , conical portion  16 , and the main body  14 . 
     An adjustable screw cap  24  closes the normally closed end  26  of the main body portion  14 . The cap  24  is provided with threads  28  on the inner wall of the cap. The threads  28  matingly engage with threads  30  on the exterior wall of the end  26 . A central plug  32  is formed in the cap  24 , the plug  32  extending outwardly from an inner end  34  of the cap  24 . The end  34 , as can be better seen in FIG. 3, forms an annular shoulder that provides a first abutting surface, against which a compression spring  40  abuts, as will be described in more detail below. 
     An intake port  42  is cut through the wall of the hollow body  12 , and an exhalation port  44  is formed in the main body portion  14 , at a location spaced apart from the intake port  42 . Positioned between the ports  42  and  44  is an exhalation peep valve  50 , which is shown in an open intake position in more detail in FIG.  7 . The valve  50  is the same valve that is used in the first and second embodiments of the present invention; therefore, its description will be omitted when the second embodiment is described hereinafter. 
     The exhalation valve  50  is mounted on a support bracket, or frame  52  that is fitted inside the main body portion  14 . The support bracket  52  is provided with an annular flange  54  that frictionally engages the inner wall of the main portion  14 . The inner corner of the flange  54  provides a second abutting surface for the compression spring  40 . 
     An inwardly extending shoulder  56  is formed on the inner wall of the main portion  14  adjacent to the area of connection between the main portion  14  and the conical portion  16 . The shoulder forms a stop when the bracket  52 , along with the peep valve  50  is forced against the shoulder  56 . 
     An intake valve  60  (FIG. 9) is mounted in the main portion  14  between an open end  22  and the bracket  52 . The intake valve  60  can be as simple as a flexible rubber gasket that forms a one-way valve that opens during inhalation. The diameter of the circular intake valve  60  is smaller than the inner diameter of the opening  20  in the main portion  14 , allowing some air to move around the intake valve  60 . The intake valve, or flap  60  is made from a flexible material, for example latex. The flap lays over the ports of the piston/bracket  52  when pressure is against 
     When the device  10  is assembled, the spring  40  abuts, at one of its ends, against the inner end, or shoulder  34 , around the plug  32 . The second end of the spring  40  abuts against the valve  50  mounted in the bracket  52 , normally forcing the peep valve in a closed position shown in FIG.  2 . The valve opens on intake of air, as shown in FIG. 8, but offers the pre-set resistance to a gas flow during exhalation. 
     When the user needs to exercise the muscles or simply distend airways, he closes his lips around the open end  22  of the mouthpiece  18 . During inhalation, the air travels from the intake port  42 , through the valve  50 , around the valve  60 , and into the open end  22  of the mouthpiece  18 . On exhalation, the flow of gas is reversed, moving from the open end  22 , around the valve  60 , and against the resistance of the compression spring  40 , into the directional exhalation port  44 . In order for exhalation gas to exit the body  12 , the user must exert sufficient pressure on the spring  40  to move the bracket  52  into a position away from the exit port  44  to allow the gas to be expelled. 
     Since the spring  40  offers resistance to the opening of the peep valve  50 , a positive back pressure is created in the airways of the patient, forcing the patient to apply more force in exhaling, thereby strengthening the muscles involved in breathing. The cap  24 , being in contact with the spring  40  can be screwed more or less tightly on the body  12 , allowing adjustment for creation of positive pressure in the range of 5 cm to 20 cm of water. This range was found sufficient for most of the patients, although other pressure adjustments may be easily made if desired. 
     Turning now to the second embodiment shown in FIGS. 4-6, the nebulizer attachment device  70  is illustrated. The device  70  comprises an elongated, generally cylindrical body  72  that has a normally open end  74  and a normally closed end  76 . An adjustable cam lever  78  is secured to a shaft connected to a piston  94  mounted in the end  76  to allow adjustment of the pressure required for opening and closing of the peep valve mounted inside the body  72 . The pressure may be adjusted to a desired value, for example in the range of 5 cm to 10 cm of water, depending on the user&#39;s condition. 
     The adjustment may be accomplished by regulating position of the lever. For example, a first position would indicate pressure of 10 cm of water. By flipping the lever in an opposite direction, the user may regulate compression of the spring to create pressure of about 5 cm of water. Of course, the movement of the cam lever  78  may be calibrated to any pressure in between the desired range, setting different positions on the body  72  and indicating the setting by suitable indicia. 
     The body  72  is provided with a directional intake port  80  and a directional exhalation port  82 . The open end  74  is adapted for frictional engagement with a manifold  84  that carries a mouthpiece  86  and a conventional nebulizer  88 . The manifold  84 , mouthpiece  86 , and nebulizer  88  are not part of this invention; they are shown in phantom lines in FIG.  4 . 
     Referring now to FIGS. 5 and 6, the interior of the device  70  is shown in more detail. As can be seen in FIG. 5, the body  72  is provided with a central opening  90  that extends from the open end  74  to the closing wall  92  of the closed end  76 . The cam lever  78  is rotatably mounted on a shaft  77  (FIG. 6) that is fixedly attached to the wall  92  of the closed end  76 . The piston  94  moves a small distance within the central opening  90  only to adjust compression of a spring  96 . 
     The compression spring  96  is mounted between the piston member  94  and the exhalation valve peep valve  98 . The valve  98  is similar is all respects to the valve  50  and, therefore its detail description is omitted here. The exhalation peep valve  98  allows creation of positive back pressure by forcing the patient to exhale against the force of the compressed spring  96 . An intake valve, similar to the valve  60  is in the body  72  between the open end  74  and the valve  98 . 
     During intake of air, the air travels through the port  80 , through the valve  98  and intake valve  60  in the direction of arrow  100 . During exhalation, or expiration, the air moves against the rubber gasket, or flap valve  60  that normally closes the ports of the piston/bracket. By continuing exhalation, the patient is able to move the bracket, against resistance of the compression spring  96 , away from the exhalation port  82 , allowing the gas to move through the exhalation peep valve  98  and through the exhalation port  82 , in the direction of arrow  102 , as shown in FIG.  6 . 
     Once the adjustable cam lever  78  is set for the desired resistance to air movement, the device  70  is mounted on the manifold  84  and becomes connected to the nebulizer  88 . A quantity of medication  104  deposited in the nebulizer  88  mixes with the air passing through the manifold  84  to the mouthpiece  86  and is delivered to the airways of the patient. The tiny droplets of medication dispersed by the aerosol-forming member  106  intercept the airflow passing through the body  72 . The formed mist mixes with the intake airflow and is delivered into the airways of the user, extending the airways and reducing the asthma attack or other breathing problems of the patient. 
     It is preferred that during exhalation or inhalation, the patients keep their mouths firmly closed around mouthpieces  18  and  86 , so as to seal the open ends of the devices  10  and  70  and to allow effective delivery of medication and exhalation of gases. When the patient exhales, the peep valve tends to distend airways of the patient and prevent collapsing of the alveoli by creating a positive back pressure. 
     When the air is forced to exit only through the exhalation valve that has been pre-set to offer resistance by a cap  24  or by the cam  78 , the exhaust airflow cannot exit through the intake port and has to move through the exhalation ports  44  or  82 . By keeping a sealed positive backpressure in the devices  10  and  70 , the airways of the patients are kept open restoring the normal breathing. Once the pressure inside the inflamed sac is equalized with the pressure in a trachea, the medication has a much better chance to penetrating deep into the airways and cause dilation. 
     The devices  10  and  70  allow trapped carbon dioxide to escape through the exhalation ports  44  or  82 , thereby reducing the toxic levels of carbon dioxide into the blood stream of the user. When the trapped gases are removed from the lungs, the lungs can then generate a greater inspiratory pressure with less effort of the patient. 
     Once the airways are extended, the pyramid effect establishes itself thus increasing the flow of much needed oxygenated air. The user, allowing pressure equalization and increase of volume in all lung areas, experiences a long expiratory phase. Once the airways are extended, the air movement into and out of the lungs is considerably improved. The lungs are not hyper-inflated; fresh air enters the lungs with more ease. 
     Additionally, if the attachment  70  is used, the medicine  104  is pulled in from the nebulizer  88  more effectively to reach the affected areas of the lungs and further dilate the airways. Consequently, the patient&#39;s collapsed or obstructed airways remain open and more precise medication delivery may be achieved. The treatment then becomes more effective with less medication. 
     The present invention can be used for patients suffering from asthma or emphysema. Many patients suffering from asthma have unexpected attacks and difficulty of getting to their medication. The attack may be enhanced by anxiety that the patient would suffocate before getting the medication. By having a small portable device readily available, the patient can at least restore some breathing and reduce the anxiety factor. 
     During an emphysema attack, the terminal bronchioles are weakened and are in a permanently enlarged condition. The alveolar walls are often times damaged. Because of the loss of alveolar space, the amount of surface area for gas exchange is reduced, and the elastic recoil of the lung tissue is diminished. 
     It is the lack of elasticity that causes inadequate lung recoil and fatigues inspiratory muscles. The lungs are unable to properly relax and return to their normal position. Under such conditions, patients are often advised to breathe with “pursed lips.” By using, the sealed back pressure devices  10  or  70 , that emphysema sufferers can increase delivery of air into the lungs and exhaust the carbon dioxide from the blood stream. 
     The backpressure created by the devices  10  and  70  prevents the bronchioles, alveoli from collapsing. The reduction of resultant hyperinflation allows the patient to inspire and exhale more fully, thereby delivering medication to a greater surface of the damaged tissue. Additionally, the sealed back pressure helps to keep the alveoli and airways open, allowing the release of the carbon dioxide from the lungs into the atmosphere. The effective removal of gas from the lungs and the blood stream improves the physiological function of the patient and allows more oxygen to be delivered into the lungs. 
     It is envisioned that the valve  10  and  70  can be preset to greater values than indicated above, particularly with patients having considerable problems with collapsed airways, although the preferred settings would range from about 5 cm to 20 cm of water. 
     It is envisioned that the devices of the present invention may be used for exercising the patients and restoring their ability to normally breathe. This is particularly true with a device  10  of the first embodiment. It is also envisioned that a nose clip and/or a molded cushioned mouthpiece may be used in combination with the mouthpieces to ensure a better seal of the patients&#39; lips around the mouthpiece. 
     The device of the present invention can be inexpensively manufactured from readily available materials, such as plastic and lightweight metal. The springs  40  and  96  will naturally be manufactured from a material that is strong enough to withstand multiple compressions and expansions during use of the device. It is envisioned that the mouthpiece  18  may be manufactured to detachably engage the main body portion  14 , if desired. In such a case, the device  10  with separated mouthpiece  18  may be carried in a compact space, such as the user&#39;s pocket, and engaged with the rest of the device, when needed. 
     The device  70  may be attached to a metered dose inhaler (MDI), instead of a nebulizer, if necessary. In such a case, a mini spacer would be used instead of the manifold  84 . The mini spacer conventionally has a port for delivery of medication, for example anti-inflammatory drugs, in the form of a fine mist. 
     Many changes and modifications may be made in the design of the present invention without departing from the spirit thereof. I, therefore, pray that my rights to the present invention be limited only by the scope of the appended claims.