Abstract:
A novel augmented incentive spirometer that will deliver pressurized oxygen, or air when the patient inhales, therefore increasing the inspired volume over the amount of volume generated only by the patient&#39;s effort.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    Not Applicable 
       STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT 
       [0002]    Not Applicable 
       INCORPORATION-BY-REFERENCE OF MATERIAL SUBMITTED ON A COMPACT DISC 
       [0003]    Not Applicable 
       BACKGROUND OF THE INVENTION 
       [0004]    1. Field of the Invention 
         [0005]    The present invention relates generally to respiratory therapy devices of the character used in daily medical practice to prevent pulmonary complications in patients who have had chest or abdominal operations. More particularly, the invention concerns a novel augmented incentive spirometer that will deliver pressurized oxygen, or air when the patient inhales, therefore increasing the inspired volume over the amount of volume generated only by the patient&#39;s effort. 
         [0006]    A spirometer is typically defined as an apparatus for measuring the volume of air inspired and expired by the lungs. More particularly, the spirometer is a differential pressure transducer for the measurements of respiration flow rates. The spirometer records the amount of air and the rate of air that is breathed in and out over a specified period of time. The commonly used prior art devices are simple, single use, disposable devices that are relatively inexpensive. The prior art spirometers are designed to encourage patients to take deep breaths that can be quantifiably and objectively seen as the patient&#39;s inspiration creates flow and a measured volume of air or air-mix flows into the lungs. The volume of air depends on the effort of the patient when taking deep breaths and the higher the volume generated by the patient, the greater the benefit. This increase in the inspired volume leads to the prevention of lung atelectasis or airways collapse. 
         [0007]    For the more compromised, weaker, and seriously ill patients, the prior art incentive spirometers simply will not provide the desired results. Accordingly, the thrust of the present invention is to provide an augmented incentive spirometer of unique design that will deliver pressurized air when the patient inhales, therefore increasing the inspired volume over the amount of volume generated only by the patient&#39;s effort. 
         [0008]    2. Description of Related Art Including Information Disclosed Under 37 CFR 1.97 and 1.98 
         [0009]    A quite popular prior art incentive spirometer is commercially available under the designation Coach 2 from the DHD Healthcare Corporation of Wampsville, N.Y. The Coach 2 incentive spirometer, which is available is available in 4,000-mL and 2,500-mL capacities, includes a one-way valve, universal graphics, a brightly colored piston, and a bedrail holder. 
         [0010]    Another prior art spirometer is disclosed in U.S. Pat. No. 3,395,699 issued to Beasley. The Beasley spirometer comprises a case, an expandable-contractible bellows supported on the case and having an inlet and an outlet. The bellows is arranged to receive gas through the inlet and expel it through the outlet during movement between expanded and contracted conditions. A first valve means is provided in the inlet to permit flow to the bellows but functions to block flow in the opposite direction. A second valve means is provided for closing the outlet. The second valve means is movable to an open position to permit gas to be expelled from the bellows. Also provided is a pneumatic actuating means that is responsive to a pressure signal from moving the second valve means to its open position and means responsive to the bellows moving to its contracted condition for causing the second valve means to move to its closed position. 
         [0011]    U.S. Pat. No. 5,107,830 issued to Younes concerns a lung ventilator device in which ventilation to a patient is provided in response to patient effort. The free flow of gas from a piston, or similar air source, in response to patient inhalation is detected, the instantaneous rate and volume of flow are measured, and the measurements are used as control signals to a drive motor for the piston to move the piston to generate a pressure which is proportional to the sum of measured and suitably amplified rate and volume of flow signals. Since the command signal to the pressure generator only changes subsequent to, and not in advance of, a change in flow and volume, the ventilator is subservient to the patient and provides a proportional assist to patient ongoing breathing effort during inspiration. 
       BRIEF SUMMARY OF THE INVENTION 
       [0012]    By way of brief summary, one form of the augmented incentive spirometer of the present invention comprises a housing having first and second portions, the first portion having an outlet and the second portion including a reservoir having an inlet and an outlet. Carried within the first portion of the housing is a piston that is movable between a first position and a second position. Connected to the housing is a combination cylinder that has a first inlet in communication with the reservoir of the second portion of the housing, a second inlet in communication with the first portion of said housing and a first outlet in communication with the outlet of the second portion of the housing. Connected to the combination cylinder and in communication with the first portion of the housing is a patient inhalation subassembly. A source of oxygen is connected to the second portion of said housing for controllably introducing oxygen into the reservoir of the second portion via a control valve that controls the flow of oxygen into the reservoir. As the piston moves between its first and second positions, an operating member which interconnects the piston with the control valve controllably operates the control valve to regulate the flow of oxygen into the reservoir. 
         [0013]    With the foregoing in mind, it is an object of the present invention to provide a novel augmented incentive spirometer that will deliver pressurized oxygen to the patient when the patient inhales, therefore increasing the inspired volume over the amount of volume generated only by the patient&#39;s effort. 
         [0014]    Another object of the invention is to provide to provide an apparatus of the character described which in operation is not totally dependent upon the patient&#39;s cooperation. 
         [0015]    Another object of the invention is to provide to provide an apparatus of the class described that will provide an augmented tidal volume during the patient inspiration step, even if the patient is unable to generate sufficient negative inspiratory pressure to generate adequate tidal volume. 
         [0016]    Another object of the invention is to provide an apparatus of the character described in the preceding paragraphs that will enable even debilitated patients to generate a negative inspiratory pressure capable of triggering the system. Accordingly, in using the apparatus of the invention the patient does not need keep inhaling to create a tidal volume that is sufficient to open up small airways and thereby prevent athelectasis. Additionally, once the patient inhales, the pressurized oxygen-air flows into the patient&#39;s lungs and becomes independent of the negative inspiratory pressure generated by the patient. 
         [0017]    Another object of the invention is to provide to provide an apparatus of the aforementioned character that includes a one-way safety valve that is disposed within an outlet port formed in the combination cylinder. 
         [0018]    Another object of the invention is to provide to provide an apparatus of the character described in which the flow of the air oxygen mixture to the patient is directly proportional to the negative inspiratory pressure (NIP) created by the patient during the inhalation step. 
         [0019]    Another object of the invention is to provide an augmented incentive spirometer of the class described that is easy to use with a minimum amount of instruction. 
         [0020]    Still another object of the invention is to provide an augmented incentive spirometer that is of a simple, inexpensive construction and one which is highly reliable in operation. 
         [0021]    The foregoing objectives, as well as other features and advantages of the present invention, will become readily apparent from the following detailed description and the accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF SEVERAL VIEWS OF THE DRAWINGS 
         [0022]      FIG. 1  is a generally perspective view of one form of the augmented incentive spirometer of the present invention. 
           [0023]      FIG. 2  is a cross-sectional view of the augmented incentive spirometer shown in  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]    Referring to the drawings, one form of the augmented incentive spirometer of the invention is there shown and generally designated by the numeral  14 . Augmented incentive spirometer  14  here comprises a housing  16  having first and second portions  16   a  and  16   b.  First portion  16   a,  which is generally cylindrical in shape, has an outlet  18 . Mounted within first portion  16   a  for movement there within between a first position and a second position is a generally cylindrical piston  20 . As best seen in  FIG. 2 , second portion  16   b  includes a reservoir  22  having an inlet  24  and an outlet  26 . 
         [0025]    Connected to housing  16  is an elongate, generally cylindrically shaped combination cylinder  28  that has an open end  28   a  that defines a first inlet  30 . Combination cylinder  28  also has a second inlet  32  that is in communication with the first portion  16   a  of said housing  16  in the manner illustrated in  FIG. 2  of the drawings. Connected to combination cylinder  28  is a patient inhalation subassembly  34 , the details of construction of which will presently be described. (See also  FIG. 1 .) 
         [0026]    Connected to second portion  16   b  of housing  16  is a source of oxygen “S” that communicates with reservoir  22  via a conventional pressure breaking valve  36  that is connected to second portion  16   b  proximate inlet the  24 . Pressure breaking valve  36  maintains the flow of oxygen from the source of oxygen into reservoir  22  at a pressure of between about  45  and about 50 pounds per square inch (psi) and maintains the rate of flow of oxygen into the reservoir at between about 600 and about 800 liters per minute. 
         [0027]    Also connected to second portion  16   b  of housing  16  proximate the outlet  26  is a control valve  38  which, in a manner presently to be described, functions to control the flow of oxygen from reservoir  22  into combination cylinder  28 . For a purpose presently to be described, combination cylinder  28  is provided with a first outlet  40 . Operably associated with control valve  38  is a control valve operating assembly  42  that functions to operate the control valve as piston  20  moves within the first portion of the housing in the manner indicated by the arrow  44  of  FIG. 2  between the first and second positions. In the present form of the invention, operating assembly  42  comprises a coil spring  42   a  and a valve operating member  42   a  that is connected to control valve  38 . As best seen in  FIG. 2  of the drawings, coil spring  42   a  interconnects the distal end of the valve operating member with the piston  20 . 
         [0028]    In the present form of the invention, the patient inhalation subassembly  34  comprises a flexible tube  46  and a patient mouthpiece  48  that is connected to the flexible tube. As illustrated in  FIG. 2 , flexible tube  46  is connected to a one-way safety valve  50  that is connected to combination cylinder  28  proximate a second outlet  52 . For further operational safety, a safety valve  54  is carried by the combination cylinder  28  proximate first outlet  40 . In the present form of the invention, safety valve  54  opens if the pressure in the combination cylinder  28  becomes greater than a pre-set pressure, which in this case is about 6 pounds psi. In using the augmented incentive spirometer of the invention, the source of oxygen “S” is first connected to the pressure breaking valve  36  in the manner shown in  FIG. 2  and oxygen is permitted to flow into reservoir  22  at a prescribed pressure and at a prescribed rate of flow. This done, the patient is requested to take a deep breath using the mouthpiece  48  of the inhalation assembly  34 . In the manner indicated by the arrows  57  in  FIG. 2 , this step causes room air to enter the open end  28   a  of combination cylinder  28  that defines a first inlet  30 . Inhalation by the patient also creates a negative pressure in the chamber  58  of the lower portion of the housing. This negative pressure causes the piston  20  to move downwardly within chamber  58 , which, in turn, causes the operating member  42   b  to pivot downwardly against the urging of spring  42   a  in a manner to open control valve  38 . Uniquely, the extent to which the control valve is opened by the operating member is directly proportional to the negative inspiratory pressure (NIP) created by the patient during the inhalation step. As the control valve opens, oxygen will flow into the combination cylinder in the manner illustrated by the arrows  60  in  FIG. 2  where it mixes with the room air. As indicated by the arrows  62  in  FIG. 2 , as the patient continues to inhale the mixture of room air and oxygen will flow into the patient&#39;s mouth simulating the “French kiss” positive pressure breathing described in the literature. Uniquely, the pressurized air oxygen mixture will continue to flow to the patient even when the patient is no longer inhaling. Accordingly, the patient does not need to continue inhaling to receive the appropriate volume of air oxygen mixture. 
         [0029]    At the point at which the negative inspiratory pressure, which is created by the patient during the inhalation step, is lower than the pressurized air oxygen mixture at the one-way safety valve  50 , the piston  20  will return to its original position. As the piston returns to its original position, the control valve  38  will close, thereby preventing further flow of the pressurized air oxygen mixture to the patient. 
         [0030]    Having now described the invention in detail in accordance with the requirements of the patent statutes, those skilled in this art will have no difficulty in making changes and modifications in the individual parts or their relative assembly in order to meet specific requirements or conditions. Such changes and modifications may be made without departing from the scope and spirit of the invention, as set forth in the following claims.