Patent Abstract:
A bi-level positive airway pressure device includes a housing that has a patient port for connecting to an airway of a patient. Within the housing is a device that generates a positive airway pressure directed towards to patient port. Also within the housing is a system that mechanically detects exhalation (by the patient that is connected to the patient port) that enters into the patient port. Responsive to detecting exhalation, a blocking device occludes the device that generating positive airway pressure, thereby reducing or stopping the positive airway pressure until the system that mechanically detects exhalation no longer detects exhalation, at which time the blocking device is operated to no longer occlude the device for generating positive airway pressure, thereby providing positive airway pressure to the patient port during, for example, inhalation.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional application No. 62/050,554 filed on Sep. 15, 2014, the disclosure of which is incorporated by reference. 
     
    
     FIELD 
       [0002]    This invention relates to the field of medicine and more particularly to an apparatus for delivering bi-level positive airway pressure. 
       BACKGROUND 
       [0003]    Patients (e.g. mammals such as humans) having respiratory issues such as chronic obstructive pulmonary disease (COPD), sleep apnea, etc., often require assistance in filling their lungs with air, or inhalation. There exist devices that are interfaced to a patient&#39;s airway for providing such assistance by injecting a positive airway pressure towards and into the patient&#39; airway, thereby assisting that patient with inhalation. 
         [0004]    One type of device for providing such assistance is a Continuous Positive Airway Pressure (CPAP) device as described in, for example, U.S. Pat. No. 4,944,310. Continuous Positive Airway Pressure devices generally provide a gas pressure that is slightly greater than ambient air pressure into the patient&#39;s airway. Continuous Positive Airway Pressure devices work well for certain patients, but patients that have poor lung capability often find it harder to exhale due to the constant added pressure directed into their air passages by the Continuous Positive Airway Pressure device, being that the Continuous Positive Airway Pressure device continues to provide positive air pressure, even while the patient is exhaling. 
         [0005]    Bi-level Positive Airway Pressure devices address this issue of exhalation as described above by detecting when the patient is exhaling and reducing the positive airway pressure until the patient completes exhalation and starts inhalation. In such, there are two different positive airway pressures delivered (hence bi-level), a higher positive airway pressure while the patient inhales and a lower positive airway pressure (e.g., atmospheric pressure) while the patient exhales. 
         [0006]    To accomplish the bi-level positive airway pressure delivery, Bi-level Positive Airway Pressure devices of current have electrical transducers that senses when the patient is exhaling and an electrical circuit that receives an electrical signal from the transducers and responsive to that signal, modulates the positive airway pressure between two values. For example, U.S. Pat. Pub. 20140150793 describes such a Bi-level Positive Airway Pressure device that has a flow sensor connected to a controller. This device has a blower for providing the positive airway pressure. Upon detecting that a patient is exhaling, the controller sets the blower to operate at a lower speed (or off), thereby reducing the positive airway pressure until the patient stops exhaling, at which time the controller detects the end of the exhalation and restarts the blower. 
         [0007]    The above described Bi-level Positive Airway Pressure devices are known to function well, especially with patients that have very little lung capacity. Unfortunately, many such patients are not limited to bed rest and wish to be mobile. It is known to provide the pressure component for positive airway pressure by a portable device, typically portable Continuous Positive Airway Pressure (CPAP) devices. Such devices typically derive the pressure component for positive airway pressure from a small battery operated pump or through a compressed gas cylinder (e.g. air, oxygen, etc.). It is possible, especially if made small and light enough to be carried by the patient. The sensors, the connections to the sensors, and the added electronics make portability hard to accomplish, especially if a compressed gas tank us utilized. Further, the issues related to battery charge maintenance become an issue. 
         [0008]    What is needed is a bi-level positive airway pressure system that has an entirely mechanical system for switching between pressures. 
       SUMMARY 
       [0009]    In one embodiment, a bi-level positive airway pressure device is disclosed including a housing that has a patient port for connecting to an airway of a patient. Within the housing is a device such as a nozzle that generates a positive airway pressure directed towards to patient port. Also within the housing is a system that mechanically detects exhalation (by the patient connected to the patient port) entering into the patient port. Responsive to detecting exhalation, a blocking device occludes the device that generating positive airway pressure, thereby reducing or stopping the positive airway pressure until the system that mechanically detects exhalation no longer detects exhalation, at which time the blocking device is operated to no longer occlude the device for generating positive airway pressure, thereby providing positive airway pressure to the patient port during, for example, inhalation. 
         [0010]    In another embodiment, a bi-level positive airway pressure device is disclosed including a housing having a patient port for connecting to an airway of a patient. The bi-level positive airway pressure device has mechanisms for generating a positive airway pressure directed towards the patient port and mechanisms for detecting exhalation entering into the patient port. Mechanisms are provided for selectively blocking the positive airway pressure, blocking the positive airway pressure when the mechanism for detecting exhalation detects exhalation (e.g. the patient breaths out), thereby making it easier for the patient to exhale. 
         [0011]    In another embodiment, a bi-level positive airway pressure device is disclosed including a housing having a patient port for connecting to an airway of a patient. A nozzle generates a positive airway pressure directed towards the patient port. The nozzle is positioned near an end of the housing distal from the patient port. A mechanical device for detecting an exhalation flow entering into the patient port is coupled to a occluding member such that upon detection of the exhalation flow, the mechanical device causes the occluding member to block the nozzle, thereby abating the positive airway pressure. 
         [0012]    In another embodiment, a bi-level positive airway pressure device is disclosed including a housing having a patient port at one end for interfacing to an airway of a patient. A nozzle that is interfaced to a supply of gas generates a positive airway pressure in a direction aimed at the patient port. The nozzle situated at an end of the housing distal from the patient port and the nozzle is directed towards the patient port. An occluding member is movably positioned between the nozzle and the patient port and is positionable in at least two positions. A first position blocks the positive airway pressure and a second position allows flow of the positive airway pressure to the patient port. A gas jet is initially aimed at a first port and during exhalation; the gas jet deflects to be aimed at a second port. The first port is in fluid communications with a first mechanical device that moves the occluding member to the second position when the first mechanical device (e.g., diaphragm) receives pressure from the gas jet, thereby enabling the positive airway pressure. The second port is in fluid communications with a second mechanical device that moves the occluding member to the first position when the second mechanical device (e.g., diaphragm) receives pressure from the gas jet, thereby abating the positive airway pressure when the exhalation flow is detected. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]    The invention can be best understood by those having ordinary skill in the art by reference to the following detailed description when considered in conjunction with the accompanying drawings in which: 
           [0014]      FIGS. 1A and 1B  illustrate cut-away views of a mechanical bi-level positive airway pressure system. 
           [0015]      FIGS. 2 and 3  illustrate plan views of the mechanical bi-level positive airway pressure system. 
           [0016]      FIG. 4  illustrates another cut-away view of the mechanical bi-level positive airway pressure system. 
           [0017]      FIG. 5  illustrates a perspective view of the mechanical bi-level positive airway pressure system. 
       
    
    
     DETAILED DESCRIPTION 
       [0018]    Reference will now be made in detail to the presently preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Throughout the following detailed description, the same reference numerals refer to the same elements in all figures. 
         [0019]    Referring to  FIGS. 1A and 1B , cut-away views of a mechanical bi-level positive airway pressure system  10  are shown. The principles of operation of the bi-level positive airway pressure system  10  are understandable from  FIGS. 1A and 1B . 
         [0020]    In  FIGS. 1A and 1B , the patient airway (not shown) is interfaced to the patient port  14  by any way known in the industry such as by a nasal cannula, face mask, etc. 
         [0021]    As shown in  FIG. 1A , during exhalation, the flow of air from the patient travels through the outer chamber  7  of the detection section  12  as indicated by the air flow arrow. A first one-way valve  44 / 46  allows flow in the exhalation direction through the outer chamber (indicated by an arrow) while a second one-way valve  40 / 42  precludes flow through the inner chamber  5  defined by an inner structure  40 . 
         [0022]    As shown in  FIG. 1B , during inhalation, the one-way valves  44 / 46 / 40 / 42  operate in an opposing fashion, in that, the flow of air from the positive pressure nozzle  20  (optionally along with atmospheric air) travels through the inner chamber  5  of the detection section  12  as indicated by the inhalation air flow arrow in  FIG. 1B . The first one way valve  44 / 46  blocks flow in the inhalation so there is no flow through the outer chamber  7  while the second one-way valve  40 / 42  allows flow through the inner chamber  5  as indicated by the inhalation flow arrow. The positive pressure nozzle  20  is provided with gas under pressure from a positive pressure input port  18 . 
         [0023]    In  FIGS. 1A and 1B , there is a pressurized gas input  30  that is connected to a source a pressurized gas (e.g. air, oxygen, etc.—not shown). A gas stream  9  flows out of a gas stream nozzle  41  and crosses the inner chamber  5  falling onto one of the receptor channels  32 / 36 . As shown in  FIG. 1A , when the patient is not inhaling (e.g., exhaling or at rest), the gas stream  9  flows directly across the inner channel  5  and into the first receptor channel  32 . The first receptor channel  32  is fluidly interfaced to a first port  34  which is connected to an input  52  of a first pressure-to-movement conversion device  50  which is explained later. 
         [0024]    As shown in  FIG. 1B , when the patient is inhaling, the gas stream  9  flowing across the inner channel  5  is deflected and flows into the second receptor channel  36 . The second receptor channel  36  is fluidly interfaced to a second port  38  which, in turn, is connected to an input  62  of a second pressure-to-movement conversion device  60  (see FIG. 
         [0025]      2 ) which is explained later. In other embodiments, the gas stream (or jet)  9  is deflected or blocked by a device linked to a diaphragm, in particular for patients with very weak lung capacity. 
         [0026]    The first pressure-to-movement conversion device  50  and the second pressure-to-movement conversion device  60  push and pull a movable occlusion device  70  that has an occluding member  72 . The occluding member  72  is moved in front of the positive pressure nozzle  20  while the patient is not inhaling, thereby blocking gas pressure that continuously flows out of the positive pressure nozzle  20  until the patient starts to inhale. When the patient starts to inhale, the gas stream  9  flowing across the inner channel  5  is deflected and flows into the second receptor channel  36 , which is in fluid communications with the second pressure-to-movement conversion device  60 , which converts the gas pressure into a movement of the occluding member  72  to a position in which the gas pressure from the positive pressure nozzle  20  is no longer blocked, thereby providing positive pressure to the patient, helping the patient inhale. When the patient stops inhaling, the gas stream  9  flowing across the inner channel  5  relaxes and flows into the first receptor channel  32 , which is in fluid communications with the first pressure-to-movement conversion device  50 , which converts the gas pressure into a movement of the occluding member  72  to a position in which the gas pressure from the positive pressure nozzle  20  is blocked, thereby reducing the positive pressure and allowing for exhalation by the patient without needing to overcome the positive pressure. An example of pressure-to-movement conversion devices  50 / 60  and the occlusion system  70 , including the occlusion device  72  is shown in  FIG. 4 . It is fully anticipated that in some embodiments, a single pressure-to-movement conversion device operates on a pressure from one or the other of the first receptor channel  32  or the second receptor channel  36  using a resilient member or the resiliency of the diaphragm to return the occlusion device to the correct position after abatement of the gas pressure. Therefore, it is fully anticipated that in some embodiments, a single pressure-to-movement conversion device  50 / 60  is used and resilient force is used to return the occlusion device  72  back to a resting position. For example, a single pressure-to-movement conversion device  60  fluidly interfaced to the second receptor channel, in which the single pressure-to-movement conversion device  60  has a resilient diaphragm in which the resilient diaphragm works to pull the occlusion device  72  into a resting position. When the patient inhales, the gas stream  9  flowing across the inner channel  5  bends and flows into the second receptor channel  36 , thereby placing air pressure upon the resilient diaphragm, thereby overcoming the resilient force of the diaphragm and moving the occlusion device  72  away from the positive pressure nozzle  20 , providing positive pressure to the patient. When the patient stops inhaling, the gas stream  9  flowing across the inner channel  5  retorts to its natural flow and no longer enters the second receptor channel  36  and the resilient force of the diaphragm moves the occlusion device  72  in front of the positive pressure nozzle  20 , allowing the patient easier of exhalation. 
         [0027]    A port  15  is provided to allow atmospheric air to flow in/out of the bi-level positive airway pressure system  10 , allowing the exhalation gases to escape and allowing fresh air to enter during inhalation. 
         [0028]    In some embodiments, the intermediate channel  16  between the positive pressure nozzle  20  and the detection section  12  is tapered to a narrower diameter to increase the velocity of the gas as it moves toward the patient. In some embodiments, the taper is a linear taper as shown in the figures. 
         [0029]    Referring to  FIGS. 2 and 3 , plan views of the mechanical bi-level positive airway pressure system  10  are shown. In this view, an exemplary outside enclosure  12  is visible as well as both pressure-to-movement conversion devices. Gas, under pressure, is connected to the pressurized gas input  30  to create the gas stream  9 . Gas, under pressure, is also connected to the positive pressure input port  18 . Although it is anticipated that the same source of pressurized gas is provided to both the pressurized gas input  30  and the positive pressure input port  18 , it is also anticipated that in other embodiments, different sources of gas are used, in some embodiments being the same gas under different pressures and in some embodiments being different gases. 
         [0030]    Referring to  FIG. 4 , another cut-away view of the mechanical bi-level positive airway pressure system  10  is shown. In this view, construction of exemplary pressure-to-movement conversion devices  50 / 60  and the occlusion system  70 , including the occlusion device  72 , is visible. 
         [0031]    Each of the exemplary pressure-to-movement conversion devices  50 / 60  has a diaphragm  54 / 64  that is interfaced to a respective push rod  56 / 66 . Air pressure from the respective ports  34 / 38  enter the pressure-to-movement conversion devices  50 / 60  from respective inputs  52 / 62  (see  FIG. 5 ) that are in fluid communications with the outer chambers  59 / 69  surrounding the diaphragms  54 / 64 . When air pressure enters the respective outer chamber  59 / 69 , the air pressure pushes against the respective diaphragm  54 / 64 , therefore, moving the respective push rods  56 / 66  in a direction towards the occlusion system  70 . The push rods  56 / 66  are coupled to the occlusion system  70 , thereby moving the occlusion device  72  either in front of the positive pressure nozzle  20  (during exhalation) or away from the positive pressure nozzle  20  (during inhalation). 
         [0032]    Note that the exemplary pressure-to-movement conversion devices  50 / 60  are examples and many other devices are anticipated that perform similar functions in various ways, including using pistons, etc. Again, it is noted that it is anticipated that in some embodiments, only a single pressure-to-movement conversion device  50 / 60  is present. 
         [0033]    Referring to  FIG. 5 , a perspective view of the mechanical bi-level positive airway pressure system  10  is shown. It is anticipated that, for example, gas tubing connects both the pressurized gas input  30  and the positive pressure input port  18  to a source of pressurize gas (not shown for brevity reasons). It is also anticipated that the first port  34  is connected to the input  52  of a first pressure-to-movement conversion device  50  by a section of gas tubing (not shown for brevity reasons) and the second port  38  is connected to the input  62  of a second pressure-to-movement conversion device  60  by another section of gas tubing (not shown for brevity reasons). In alternate embodiments, it is equally anticipated that the first port  34  is directly connected to the input  52  of a first pressure-to-movement conversion device  50  through a channel formed in the body of the bi-level positive airway pressure system  10  and the second port  38  is directly connected to the input  62  of a second pressure-to-movement conversion device  60  through another channel formed in the body of the bi-level positive airway pressure system  10 . 
         [0034]    Equivalent elements can be substituted for the ones set forth above such that they perform in substantially the same manner in substantially the same way for achieving substantially the same result. 
         [0035]    It is believed that the system and method as described and many of its attendant advantages will be understood by the foregoing description. It is also believed that it will be apparent that various changes may be made in the form, construction and arrangement of the components thereof without departing from the scope and spirit of the invention or without sacrificing all of its material advantages. The form herein before described being merely exemplary and explanatory embodiment thereof. It is the intention of the following claims to encompass and include such changes.

Technology Classification (CPC): 0