Abstract:
A system, device, and method of providing concurrent or contiguous breathing treatments for the purposes of clearing secretions from the lungs, expanding the airways, and delivering medicated aerosol is provided. In one embodiment, a device is provided for administering medicated aerosol delivery, lung expansion therapy, and/or secretion clearance therapy either concurrently or contiguously.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims the benefit, under 35 U.S.C. §119(e), of U.S. Provisional Application No. 61/257,350 which was filed Nov. 2, 2009 and which is hereby incorporated by reference herein. 
     
    
     BACKGROUND 
       [0002]    The present disclosure relates, in general, to a respiratory therapy device and method. More specifically, the present disclosure relates to a device and method of providing a composite breathing treatment for the purposes of clearing secretions from the lungs, expanding the airways, and delivering medicated aerosol. 
         [0003]    Atelectasis is the partial or total collapse of the lung. Although this condition may occur as a result of pressure being exerted from outside the lungs by such maladies as a tumor or fluid buildup in the pleural space, it is most often caused by obstruction within the airways. When blockage develops, the air in the small air sacs, or alveoli, on the distal side of the obstruction is absorbed into the bloodstream and the air sacs become diminished in size or collapse. These alveoli then often fill with blood cells, mucus, or serum, making them highly susceptible to infection. Atelectasis may happen suddenly or may gradually manifest over a long period of time. In either case, the disorder may lead to shortness of breath, decreased oxygen levels, increased heart rate, and infection, which in turn, can result in outcomes ranging from simple discomfort to death. 
         [0004]    Traditionally, prevention and treatment of atelectasis has included a wide variety of devices that facilitate treatment in three main areas: 1) medicated aerosol delivery, 2) lung expansion therapy, and 3) secretion clearance therapy. The variety of devices used in these therapies present a number of problems. First, for any given patient it is difficult to know in advance which therapy or combination of therapies is most appropriate. After assessing the patient at bedside, the clinician may decide that the patient requires a different therapy than planned, at which point he or she may need to return to a supply room to secure the proper therapy device or devices. This can be time consuming and can delay treatment at a time when prompt application of treatment is desirable. Second, in order to be prepared to deliver appropriate therapy, the healthcare provider may need to stock a number of devices, which presents the provider with the requirements of storage space and the need to deal with a number of suppliers. Furthermore, maintaining a number of different devices, and their attendant disposable accessories, to provide multiple therapy options increases costs to the healthcare provider and ultimately the patient. Third, in order to adequately operate various devices, a clinician may need to attend multiple training sessions, further increasing costs to the healthcare provider and patient. 
         [0005]    An additional drawback found with known existing devices is that no single device is believed to be capable of delivering aerosol, lung expansion, and secretion clearance therapies concurrently or contiguously, even though such uses may enhance respiratory therapy. For example, if airway oscillation is administered externally with a circumferential chest band that supplies a compressive oscillating pulse to the chest wall, concurrent positive pressure lung expansion therapy delivered internally to the airways may enhance the secretion clearance effects of the external oscillation. Additionally, simultaneous medicated aerosol included in the therapy mix could enhance the efficacy of both airway oscillation and airway expansion. If airway oscillation is administered internally by means of pulsatile positive pressure, it would be beneficial to seamlessly change the therapy mode to airway expansion without interruption in order to prevent possible collapse of airways between therapy modes. As in the previous example, medicated aerosol delivered during both the internal airway oscillation therapy and the airway expansion therapy could augment both therapies. 
         [0006]    Thus, there has been a need for a single apparatus which is capable of delivering a number of different breathing therapies, as well as a method of delivering concurrent or contiguous therapies, thereby eliminating the need for multiple devices and separate therapies, but which is also cost effective and does not significantly increase the time required to train operators in its use. 
       SUMMARY 
       [0007]    The present invention comprises an apparatus or method, that has any one or more of the features listed in the appended claims and/or any one or more of the following features, which alone or in any combination may comprise patentable subject matter: 
         [0008]    A device according to the present disclosure operates to deliver high frequency airway oscillation, continuous positive airway pressure (CPAP), and aerosol therapy either concurrently or contiguously. Such a device, therefore, combines aerosol delivery, lung expansion therapy, and secretion clearance therapy into a single device and a method of treatment which combines multiple treatments in either a concurrent fashion or immediately proximal to one another. 
         [0009]    In one aspect of the present invention, aerosol delivery can be combined with either pulsatile positive gas flow internal to the patient&#39;s airways to provide a secretion clearance mode, or with a linear positive gas flow to provide a lung expansion mode. A third mode of operation is also disclosed in which linear gas flow without aerosol delivery may be provided to the patient. Further, the pulsatile gas flow can be connected to the bladder(s) of a chest band that fits circumferentially around the patient&#39;s chest in order to supply a compressive oscillating pulse to the chest wall. The oscillating pulse to the chest wall may provide external airway oscillation. 
         [0010]    Some embodiments may comprise a gas control box, a patient interface circuit, and a chest wall band. The gas control box may control the flow of gas from the gas source to the patient interface circuit and/or the chest wall band. The patient interface circuit may be of single patient use, may use a fixed venture, and may have at least one orifice open to the atmosphere for entrainment. The patient interface circuit may also include at least one exhalation opening which can be adjusted to maintain a positive pressure in the lungs at the end of exhalation (Positive End Expiratory Pressure or PEEP) without the stacking of successive volumes of gas in the airways (breath stacking). PEEP helps to open the airways and keep them open during the therapy. 
         [0011]    The chest wall band may contain a bladder or multiple bladders and may wrap circumferentially around the patient&#39;s chest. The chest wall band may be single patient use. The apparatus may be designed to minimize both clinical training requirements and operator errors during treatment. Additionally, with several therapies combined into one machine, the clinician can change therapies near instantly as needed without having to return to an equipment storage area to retrieve other devices. Storage requirements are reduced and the healthcare provider can deal with a single source vender for supplies, training, and repairs. It is expected that the healthcare provider would also achieve significant cost savings through the reduction in the number of different types of equipment required to perform the various treatments performed by the current apparatus. 
         [0012]    According to this disclosure, therefore, disclosed embodiments may improve respiratory treatment by providing an apparatus or method with the capability to administer multiple respiratory treatments in combination or contiguously. Disclosed apparatuses and methods allow selection between multiple respiratory treatment options. 
         [0013]    Among the therapies or respiratory treatments that may be possible by using the apparatuses and methods of the present disclosure include provision of aerosolized medicament, supply of a continuous positive gas flow, and supply of a pulsating continuous gas flow. In some contemplated embodiments, respiratory treatment if provided by an apparatus incorporating a patient interface having a venturi tube in connection with at least one aperture open to the ambient that allow ingress and egress of flow. 
         [0014]    Also according to this disclosure, respiratory treatment is provided by an apparatus incorporating a chest wall band for administering compressive oscillating pulses to the chest wall. The chest wall band may administer compressive oscillating pulses to the chest wall and a patient interface may be operable to provide aerosolized medicament, such as via a nebulizer. Alternatively or additionally, the chest wall band may administer compressive oscillating pulses to the chest wall and the patient interface may be operable to provide linear gas flow. Further alternatively or additionally, the chest wall band may administer compressive oscillating pulses to the chest wall and the patient interface may be operable to provide either a linear gas flow or a pulsating gas flow. Thus, according to the present disclosure, respiratory treatment may be provided by an apparatus operable to select between operating an external compressive therapy, a positive lung pressure therapy, a medicated aerosol therapy, or any combination of the therapies. 
         [0015]    Additional features, which alone or in combination with any other feature(s), such as those listed above and those listed in the claims, may comprise patentable subject matter and will become apparent to those skilled in the art upon consideration of the following detailed description of various embodiments exemplifying the best mode of carrying out the embodiments as presently perceived. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0016]    The detailed description particularly refers to the accompanying figures, in which: 
           [0017]      FIG. 1  is a diagrammatic view of one embodiment of the composite lung therapy apparatus according to the present disclosure; and 
           [0018]      FIG. 2  is a perspective view of one embodiment of an injector nozzle. 
       
    
    
     DETAILED DESCRIPTION 
       [0019]      FIG. 1  shows a schematic diagram of an embodiment of the composite lung therapy breathing treatment apparatus comprising a gas control box  100 , a chest band  102 , and a patient interface circuit comprised of a breathing head assembly  104 , circuit tubes  106 ,  108  and  110 , and a nebulizer  112 . Circuit tubes  106 ,  108  and  110  are preferably a small bore (⅛″ ID) tube, but as one skilled in the art will appreciate other dimensions may be used and remain within the scope and spirit of the present disclosure. 
         [0020]    Gas control box  100  is depicted with a display  114  and a speaker  116 . Display  114  may be any visual indicator, such as an indicator light, an analog screen, a digital screen, a mechanical gauge, printed material, and/or any other known or yet to be discovered display. Speaker  116  is shown to represent an audible output device. As one skilled in the art will recognize, any audible output device, such as a bell, buzzer or other mechanical or electrical audible output device, may be incorporated instead of or in combination with speaker  116  and remain within the scope and spirit of the present disclosure. Display  114  and speaker  116  may provide system alerts, timer capabilities, and/or patient information entered in the system or monitored by the system. 
         [0021]    Gas control box  100  also includes user controls, depicted as switch  118 , knobs  120 , and buttons  122  in the illustrated example. As one skilled in the art will recognize, user controls may include switches, knobs, buttons, touch-screen displays, voice-activated switches or functions, and/or any other known or yet to be discovered type of control device. In addition, the number, arrangement, and type of user control(s) may vary and remain within the scope and spirit of the present disclosure. 
         [0022]    Gas control box  100  also includes a number of input and/or output couplers or fittings  124 ,  126 ,  128 ,  130 , and  132 . As one skilled in the art will recognize, the number, arrangement, and type of fittings may vary and remain within the scope and spirit of the present disclosure. For example, gas control box  100  is depicted with fittings  124  and  126  in the front, fittings  128  and  130  in the side, and fitting  132  on the top. In the depicted embodiment, fittings  128 ,  130 , and  132  are in operable connection with the patient interface circuit, fitting  126  is in operable connection with chest band  102 , and fitting  124  is available for connection to an additional device. Each fitting  124 ,  126 ,  128 ,  130 , and  132  may be associated with a dedicated purpose or capable of use for multiple purposes, and the following descriptions of specific purposes for the various fittings are intended as examples associated with the embodiment depicted and are not intended to limit the scope and spirit of the present disclosure. 
         [0023]    Fitting  126  of gas control box  100  is connected to chest band  102  at chest band fitting  136  via chest band tube  134 . Chest band  102  is depicted as a circular band  138  with a set of inflatable bladders  140  attached to the interior side of chest band  138 . Chest band  138  is intended to fit around the chest of a patient to provide external compressions to assist in and/or facilitate breathing of the patient. As one skilled in the art will recognize, chest band designs and apparatuses other than chest band  102  depicted in this embodiment and other external compressive breathing aides may be used and remain within the scope and spirit of this invention. For one example, a chest band with a single inflatable bladder instead of the multiple bladders  140  depicted may be used to provide the desired oscillating chest compressions. In other embodiments, a vest having one or more air bladders is provided in lieu of chest band  102 . 
         [0024]    During operation, chest band  102  is secured around the chest of a patient. Once secured, bladders  140  are inflated to an appropriate pressure to compress the chest wall causing a patient to exhale, then bladders  140  are deflated allowing decompression of the chest cavity and the patient to inhale. Bladders  140  continue to inflate and deflate creating an oscillation between the compression and decompression of the chest cavity and the associated exhalation and inhalation of the patient. Gas control box  100  may provide a linear and/or an interrupted gas flow to bladders  140 . The compressive pressure may be monitored at chest band  102 , at gas control box  100 , and/or by a separate pressure monitoring device. In one embodiment contemplated by the present disclosure, gas control box  100  outputs gas via fitting  126  into bladders  140  until the desired upper pressure is achieved, then gas control box  100  removes gas from bladders  140  until a desired lower pressure is reached and repeats the process. In another embodiment according to this disclosure, gas control box  100  outputs gas to pressurize bladders  140 , then, once an upper pressure is achieved, a gas release valve provides controlled decompression of bladders  140  until the lower pressure is reached. When the lower pressure is reached the gas release valve closes causing bladders  140  to re-pressurize using the gas flow from gas control box  100 . As one having skill in the art will recognize, a gas release valve may be located in a variety of locations in operable association with bladders  140 , including incorporated with chest band  102  or gas control box  100 , and remain within the scope and spirit of the present disclosure. 
         [0025]    In the illustrated embodiment, gas control box  100  is also in operable connection with a patient interface circuit comprising a breathing head assembly  104 , circuit tubes  106 ,  108  and  110 , and a nebulizer  112  as previously mentioned. Circuit tube  110  connects by one end to fitting  128  of gas control box  100  and by the other end to nebulizer  112 . Fitting  130  connects to one end of circuit tube  108 , and the other end of circuit tube  108  connects to pulsating gas input  142  in the rearmost end of breathing head assembly  104 . Circuit tube  106  also connects to pressure monitoring port  144  in the rearmost end of breathing head assembly  104 . 
         [0026]    The patient interface breathing head assembly  104  depicted comprises injection nozzle  142 , mouthpiece  148 , nebulizer  112 , pulsating gas input  142 , nebulizer gas input  150  and pressure monitoring port  144 . In this embodiment, breathing head assembly  104  is shown having a rear cavity  152  associated with a front cavity  154  by means of a venturi tube  156  and pressure monitoring port  144  associated with front cavity  154  by means of feedback tube  158 . Mouthpiece  148  and mouthpiece opening  160  are removably attached to the front cavity  154  at the front end of breathing head assembly  104 . Nebulizer  112  is removably attached to aerosol entrainment port  162 . Aerosol entrainment port  162  is located toward the rear end of breathing head assembly  104 , and operatively associated with rear cavity  152 . Some embodiments allow for pieces to be removably attached, but any form of removable, permanent, or other type of attachment remains within the scope of the present disclosure. As one having skill in the art will appreciate, many attachment means are known in the art and remain within the scope of the present disclosure. 
         [0027]    Circuit tube  110  connects to nebulizer gas input  150  of nebulizer  112 , which, in turn, connects to aerosol entrainment port  162  located at the rearmost portion of breathing head assembly  104 . Circuit tube  108  connects to the rearmost end of breathing head assembly  104  by connecting directly to pulsating gas input  60  which feeds directly into injector nozzle  146 . On the side wall of breathing head assembly  104  is at least one forward aperture  164  which opens the front cavity  154  of breathing head assembly  104  to the atmosphere. The forward portion of venturi tube  156  opens into front cavity  154 . Feedback tube  158  comprises a first opening adjacent to the forward opening of venturi tube  156  and a second opening that is adjacent to rear cavity  152 . 
         [0028]      FIG. 2  shows an embodiment of injector nozzle  146 , which is inserted into rear cavity  152  at the rear portion of breathing head assembly  104 . Adjacent to injector nozzle  146  in this embodiment are a plurality of aft apertures  168  which open breathing head assembly  104  to the ambient atmosphere. Pulsating gas input  142  is shown at the rear of injector nozzle  146 . This figure also shows pressure monitoring port connection  170  at the top of injector nozzle  146 . 
         [0029]    Operation of the patient interface circuit begins by loading a predetermined liquid medicament into nebulizer  112  by first detaching it from aerosol entrainment port  162 . After filled nebulizer  112  is reattached, therapy is initiated through the user controls of the gas control box  100 . Gas travels from gas control box  100  via fitting  128  through circuit tube  110  to the bottom of nebulizer  112 . Nebulizer  112  converts the liquid medication into aerosol which enters into aerosol entrainment port  162 , ushering the aerosol into rear cavity  152  of breathing head assembly  104 . 
         [0030]    Gas control box  100  outputs a high-frequency gas flow via fitting  130  which travels through circuit tube  108  to pulsating gas input  60 . Gas control box  100  may create the high-frequency gas flow by interrupting a steady gas flow at a pre-set rate, a user defined rate, or a rate based upon monitored patient conditions. In some contemplated embodiments, the gas flow is interrupted at a rate of at least 1 hertz and at most 15 hertz and the gas flow becomes pulsatile with a substantially constant pressure amplitude. In addition, a user may be able to define the interrupted rate within a limited pre-set range of rates. For example, a user may be able to define a rate within the range of at least 1 hertz and at most 15 hertz. As will be appreciated by one having skill in the art, circuit connectors or direct connections may be used to connect to gas inputs or exhausts and will remain within the scope of the present disclosure. Here, the high-frequency pulses enter injector nozzle  146  which directs them into the rear opening of venturi tube  156 . Simultaneously, the increased velocity resulting from the narrowing of injector nozzle  146  lowers surrounding pressures creating a vacuum effect, first described by Swiss mathematician Daniel Bernoulli in 1738, pulling in or entraining additional gas as well as medicament from nebulizer  112 . Second, the friction between the high speed molecules and the adjacent low-speed molecules has the effect of pulling the low-speed gas molecules into the stream of the high speed gas. 
         [0031]    In effect, ambient gas is pulled into the rear cavity of breathing head assembly  104  through aft apertures  168  (shown in  FIG. 2 ) and aerosol entrainment port  162 . As the velocity of the gas increases, the volume of entrained gas increases, and, therefore, overall flow increases. 
         [0032]    The continuous high-frequency pulsatile flow enters into venturi tube  156  which may either amplify or attenuate it. As the flow enters venturi tube  156 , given little or no resistance at mouthpiece opening  160 , the flow is amplified. However, as resistance at mouthpiece opening  160  increases, such as would result from the backpressure caused by a patient exhaling into mouthpiece opening  160 , the entrainment process is impeded and overall flow is attenuated. Velocity within the venturi decreases, and, in turn, entrainment and flow both decrease. Thus, the device allows the patient to exhale back into it, and the device is provided with a built-in safety mechanism. As the patient exhales or airway compliance decreases, resistance downstream from the venturi tube increases. The resulting decrease in delivered flow also decreases pressure, thereby protecting the airways and allowing the patient to exhale. As one skilled in the art will recognize, mouthpiece  148  may be replaced by a breathing mask, endotracheal tube, or any other known or yet to be discovered means to couple a patient&#39;s airways to the patient interface circuit and remain within the scope and spirit of the present disclosure. 
         [0033]    The mixture of high-frequency pulsatile flow from injection nozzle  146 , aerosol from aerosol entrainment port  162 , and ambient air entrained from aft apertures  168  (shown in  FIG. 2 ) continues through the lumen of venturi tube  156 , exiting its forward opening into mouthpiece  148  and out mouthpiece opening  160  to the patient. The patient seals his or her lips around mouthpiece  148  and inhales the aerosolized pulses of gas, taking them deep into the lungs. The patient then exhales back into mouthpiece opening  160  as the therapy continues. The combination of aft apertures  168  (shown in  FIG. 2 ) and forward aperture  164  allow both ingress and egress of flow, serving both inhalation and exhalation without the need for complex mechanisms to open and close valves during the therapy. 
         [0034]    As the patient continues the high-frequency oscillation breathing therapy, several processes may begin. The medicated aerosol and the oscillation of the air column in the conducting airways may help reduce viscosity of the secretions. The bi-level flow created by high-frequency intermittent delivery of gas may also begin to create wind shear forces. Specifically, during the therapy a small pulse enters the airways, and then the flow momentarily stops. During this pause, the pressure in the upper airways drops. Small volumes of gas that were previously delivered into the airways now begin to exit, momentarily unencumbered by the low pressure condition in the upper airways. As these exiting volumes of gas increase in velocity, they continually push secretions from small distal airways to the larger openings in the upper airways where they can be more easily removed. 
         [0035]    Throughout the high-frequency oscillation therapy session, the intermittent positive-pressure pulses continue as the patient inhales and exhales through mouthpiece opening  160 . The exhaled breath travels from mouthpiece opening  160  into front cavity  154  and exits forward aperture  164 . Aft apertures  168  (shown in  FIG. 2 ) and forward aperture  164  are calibrated with the interrupted rate of flow provided by gas control box  100  so that the patient is able to exhale back into mouthpiece opening  160  even as the high-frequency positive gas flow continues. This calibration allows ample opportunity for exhaled breath to escape in order to prevent the successive stacking of inhaled breaths in the airways. 
         [0036]    During the high-frequency oscillation therapy session, the patient&#39;s lung pressure may be monitored by attaching a pressure sensor such as a manometer to pressure monitoring port  144  which is associated with the second opening of feedback tube  158 . The first opening of feedback tube  158  opens into front cavity  154  and is operatively associated with mouthpiece  148  to improve lung pressure monitoring. The illustrated embodiment is shown with feedback tube  158  having a first opening near mouthpiece  148  to improve the accuracy of the pressure reading and a second opening adjacent to rear cavity  152  to improve the ease of patient handling. As one skilled in the art will appreciate, other positions of a feedback tube may be employed and the feedback tube may be used as a connecting piece and still remain within the scope of the present disclosure. The second opening of feedback tube  158  is operably associated with pressure monitoring port  144 . In this embodiment, pressure monitoring port  144  is connected to gas control box  100  via circuit tube  106  and fitting  132 . Gas control box  100  monitors the gas flow input through fitting  132 . In this embodiment, the monitored gas flow input reflects the pattern of a patient&#39;s breathing cycle which gas control box  100  illustrates on display  114 . 
         [0037]    Collar  166  may be placed over forward aperture  164  to partially occlude forward aperture  164  and affect the ingress and egress of air from front cavity  154 . The rotation of collar  166  may be used to allow a variable occlusion to occur over forward aperture  164  depending on the amount of rotation which brings differently sized notches or openings in collar  166  into registry and communication with opening  164  in front cavity  154 . 
         [0038]    The body of breathing head assembly  104  may be made of a unitary construction that incorporates a first cavity, which in the embodiment shown is front cavity  154 , a second cavity, which in the embodiment shown is rear cavity  152 , a first passageway, which in the embodiment shown is venturi tube  156 , a second passageway, which in the embodiment shown is feedback tube  158 , forward aperture  164 , and an entrainment cavity, which in the embodiment shown is aerosol entrainment port  162 . While unitary construction is used in some embodiments according to the present disclosure, it will be appreciated by one having skill in the art, unitary construction is not necessary and other forms of construction are within the scope and spirit of the present disclosure. 
         [0039]    As one skilled in the art will recognize, although the described operation of the patient interface circuit provides a medicated aerosol treatment therapy, the therapy may be administered without medicated aerosol and remain within the scope and spirit of the present disclosure. For example, nebulizer  112  may be removed allowing aerosol entrainment port  162  to be open to the ambient atmosphere allowing ingress and egress of air. Alternatively, nebulizer  112  may be removed and aerosol entrainment port  162  capped off preventing aerosol entrainment port  162  from being open to the ambient atmosphere. As another alternative, nebulizer  112  may contain a non-medicated water-based solution that provides humidity to the gas flow to help prevent drying of the patient&#39;s airways during respiratory treatment. 
         [0040]    Additionally, the high-frequency gas flow described herein is for illustrative purposes of the given embodiment and is not intended to limit the present disclosure. As one skilled in the art will recognize, respiratory therapies may incorporate or use a variety of pulsatile and/or linear gas flow rates and remain within the scope and spirit of the present disclosure. 
         [0041]    The user controls may be used to control the parameters of the given respiratory treatment. For example, a user may set the upper pressure and lower pressure for compressions to be applied to the patient with chest band  102 . Additionally, the user may set an oscillation rate to administer the chest band compressions, any desired alert conditions, time limits for compression therapy and/or any other parameters for compression therapy. Additionally, the user may set an interrupted rate of gas flow, feedback airflow monitoring parameters, time limits, and other parameters for the patient interface circuit. In addition, the user may set the compression therapy and the patient interface circuit to be administered concurrently. Alternatively, the compression therapy may be set to be administered for a given amount of time at which the compression therapy stops and the therapy through the patient interface circuit immediately begins. As one skilled in the art will recognize, the timing and overlap of any of the respiratory therapies may be set by the user controls and may vary in any number of ways and remain within the scope and spirit of the present disclosure. In addition, as one skilled in the art will recognize, the user may be any person operating the device including a patient, medical personnel, and others acting on behalf of a patient. 
         [0042]    Although certain illustrative embodiments have been described in detail above, many embodiments, variations and modifications are possible that are still within the scope and spirit of this disclosure as described herein and as defined in the following claims.