Abstract:
An airway adaptor that measures the concentration of at least one of a specific component and the flow rate of a supply gas and a return gas. The airway adapter may include a tube having a flow path in which the supply gas and the return gas passes. The tube may include a first end having a first aperture for guiding the supply gas into the flow path, and second end having a second aperture for guiding the return gas. Further, the airway adapter may include a measurement device operable to measure at least one of the supply gas and the return gas in the air flow path and a partial shielding disposed at the first aperture and structured to shield a portion of the air flow path. The supply gas may be a respiratory gas and the return gas may be inhaled or exhaled breath of a person.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    This application claims priority to Japanese Patent Application No. 2009-033627 filed on Feb. 17, 2009 in the Japan Patent Office, the disclosure of which is incorporated herein in its entirety by reference. 
         [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a gas flow system, adaptor, and method, and more particularly to a gas flow system, adaptor, and method that may include a respiratory concentration sensor that measures the concentration of a selected component in the respiratory system, such as a gas including exhaled or inhaled air of a person who will be measured, a respiratory flow sensor that measures the respiratory flow rate, and an airway adaptor for use in these sensors. 
         [0004]    2. Description of the Related Art 
         [0005]    In the related art, a respiratory gas sensor for optically measuring the concentration of, for example, carbon dioxide in a person&#39;s breath is shown in Japanese published unexamined application No. 2001-66243. Such a sensor can optically detect the change over time of the concentration of, for example, carbon dioxide in the respiratory by passing the breath such as exhaled or inhaled air of a person who is being measured through an airway adaptor equipped with an optical sensor. In addition, there is also a method of measuring the concentration by sampling a portion of the breath from the person whose respiration is being measured. When such a respiratory gas sensor is used in a patient who needs respiratory management assistance, the airway adaptor is usually provided between the tube inserted into a patient&#39;s body, for example, the trachea, and an artificial respirator. The respiratory flow rate sensor is also provided at the same location. 
         [0006]    In the case of respiratory management in a patient using an artificial respirator in this way, air may be steadily supplied from the artificial respirator to the patient in addition to periodic insufflation. As such, it is difficult to accurately measure the breathing of a patient, such as an infant who has low ventilation, by a steady influx of air from the artificial respirator into an airway adaptor. 
       SUMMARY OF THE INVENTION 
       [0007]    In order to solve the problem mentioned above, exemplary embodiments of the present invention may provide an airway adaptor operable to measure the concentration of at least one of a specific component and the flow rate of a supply gas and a return gas. The airway adapter may comprise a tube having a flow path in which the supply gas and the return gas passes, the tube including a first end having a first aperture for guiding the supply gas into the flow path, and second end having a second aperture for guiding the return gas; a measurement device operable to measure at least one of the supply gas and the return gas in the air flow path; and a partial shielding disposed at the first aperture and structured to shield a portion of the air flow path. The supply gas may be a respiratory gas and the return gas may be inhaled or exhaled breath of a person. 
         [0008]    The airway adaptor may also include a partial shielding part provided at the first aperture side for shielding a portion of said air flow path. The airway adaptor of the present invention, in an exemplary embodiment, may have a pair of translucent windows that are provided facing opposite each other along the inner wall of said air flow path, allowing the detection light irradiated from the outside of the tube from a measurement device. 
         [0009]    In this way, the gas, such as air can be suppressed from flowing into the air flow path of an airway adaptor even when the airway adaptor is connected to an artificial respirator that supplies air constantly. 
         [0010]    Furthermore, in the airway adaptor of the present invention, the pair of translucent windows may be provided along the inner wall mentioned above located by the side of the air flow path at the time of using the airway adaptor, with the partial shielding part shielding a portion excluding the lower side of said air flow path. 
         [0011]    In this way, dew condensation water generated inside the air flow path, or that has flown inside the air flow path, is not stopped at the partial shielding part, preventing it from accumulating inside the flow path. 
         [0012]    Moreover, in the airway adaptor of the present invention, the partial shielding part may be provided in the proximity of said first aperture. 
         [0013]    In this way, the inflow of the air into the air flow path can be effectively controlled. 
         [0014]    Also, in the airway adapter of the present invention, the partial shielding part may be provided integrally with the tube. 
         [0015]    In this way, the partial shielding part can be provided in the tube without increasing the number of components. 
         [0016]    Also, in the airway adapter of the present invention, the width of the second aperture of the partial shielding part may be narrower than that of the first aperture. 
         [0017]    In this way, the increase in the outflow resistance by said partial shielding part can be suppressed when the breath [exhaled air] from the person to be measured is emitted from the airway adaptor. 
         [0018]    The present invention may also include a respiratory concentration sensor that is equipped with an airway adaptor having either configuration mentioned above, as well as a part for optically measuring the concentration of a specific component in the breath of the person to be measured. Furthermore, in another exemplary embodiment, the respiratory flow rate sensor may be equipped with an airway adaptor having either configuration mentioned above, as well as a part for measuring the respiratory flow rate of the person to be measured. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]    These and other features of this disclosure will be more readily understood from the following detailed description of the various aspects of the disclosure taken in conjunction with the accompanying drawings that depict various embodiments of the disclosure, in which: 
           [0020]      FIG. 1  is an external view of an exemplary embodiment of an airway adaptor; 
           [0021]      FIG. 2  is a top view of the airway adaptor; 
           [0022]      FIG. 3  is a front view of the airway adaptor; 
           [0023]      FIG. 4  is a bottom view of the airway adaptor; 
           [0024]      FIG. 5  is a left side view of the airway adaptor; 
           [0025]      FIG. 6  is a right side view of the airway adaptor; 
           [0026]      FIG. 7  is a cross-section of section A-A of  FIG. 3 ; 
           [0027]      FIG. 8  is a cross-section of section B-B of  FIG. 4 ; 
           [0028]      FIG. 9  is an enlarged sectional view showing an enlarged view in the proximity of the first aperture of section C-C of  FIG. 6 ; 
           [0029]      FIG. 10  is a right side view of the airway adaptor equipped with partial shielding materials; 
           [0030]      FIG. 11  is a right side view of the airway adaptor equipped with partial shielding materials; 
           [0031]      FIG. 12  is a right side view of the airway adaptor equipped with partial shielding materials; and 
           [0032]      FIG. 13  is a right side view of the airway adaptor equipped with partial shielding materials. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0033]    The present invention will now be described more fully with reference to the accompanying drawings.  FIG. 1  is an external view of the airway adaptor  10  according to an exemplary embodiment of the invention.  FIG. 2 ,  FIG. 3 , and  FIG. 4  are top, front, and bottom views of the airway adaptor  10 , respectively.  FIG. 5  and  FIG. 6  are left and right side views of the airway adaptor  10 .  FIG. 7  is a cross-section of section A-A of  FIG. 3 , and  FIG. 8  is a cross-section of section B-B of  FIG. 4 . 
         [0034]    Airway adaptor  10  may be used when optically measuring the concentration of a specific component in the breath of a person to be measured, for example, a patient who needs respiratory management, and it may be equipped with a tube  20  in which an air flow path  23  has been formed for passing through the respirator into the inside. This airway adaptor  10  may be used for measurement by connecting one end of the tube  20  to an air supply and respiratory outlet of an artificial respirator through a connecting part consisting of, for example, Y-shaped tube, etc., and connecting the other end of said tube  20  to a tube inserted into the trachea of a person to be measured, for example. 
         [0035]    A respiratory-side adaptor  21  secured to said connecting part may be provided to one end of the tube  20 , and a patient-side adaptor  22  secured to said tube may be provided to the other end. Moreover, a first aperture  25  may be provided to one end mentioned above in an air flow path  23  for guiding the air supplied from the artificial respirator during said measurement; a second aperture  26  may be provided to the other end mentioned above for guiding the exhaled air of a person being measured during said measurement. 
         [0036]    At the air flow path  23 , a pair of translucent windows  24  formed by a transparent part may be provided opposite each other along the inner wall of said air flow path  23 . A measuring part (not shown in the drawing) consisting of a light-emitting part and a light-receiving part may be installed at the pair of translucent windows  24  during said measurement. More specifically, a light-emitting surface of the light-emitting part that emits optical bandwidth (detected light) including absorption spectra of a component subjected to measurement in the breath, along with a light-receiving surface of the light-receiving part that receives the detected light from said light-emitting part, may be installed at the pair of translucent windows  24  so that they are facing opposite to each other on the same optical axis. 
         [0037]    By aligning the light-emitting part and light-receiving part in such a way as mentioned above with respect to the pair of translucent windows  24 , the detected light emitted by the light-emitting part may be transmitted through the pair of translucent windows  24 , then received at the light-receiving part. In this way, the concentration of the component subjected to measurement included in the breath of a person to be measured can be measured by a known method. As the component subjected to measurement, for example, carbon dioxide can be mentioned. 
         [0038]    By the way, the airway adaptor  10  of this embodiment may be equipped with a partial shielding part  27  formed integrally with a tube  20  in the proximity of the first aperture  25  on the air flow path  23 . The partial shielding part  27  may be provided so that it shields a portion of the air flow path  23 , as shown in  FIG. 1 ,  FIG. 6 ,  FIG. 7 , and  FIG. 8 . This partial shielding part  27  has the role of making the air from said artificial respirator difficult to flow into the air flow path  23  when, for example, the respiratory-side adaptor  21  of the airway adaptor  10  has been connected to the artificial respirator that constantly supplies air. 
         [0039]    In this way, because the airway adaptor  10  of this embodiment is provided with the partial shielding part  27  in the proximity of the first aperture  25 , this can prevent thinning of the air exhaled by the person being measured and that flows into the air flow path  23  from the second aperture  26  by the constant air flown from said artificial respirator at the center of the air flow path  23 , in other words, the part where said pair of translucent windows  24  is provided. Therefore, this allows accurate measurement of the concentration of the component subjected to measurement included in the air exhaled by the person being measured. 
         [0040]    In the airway adaptor  10  of this embodiment, the installation location of the partial shielding part  27  is not limited to the proximity of the first aperture  25  on the air flow path  23 . For example, the partial shielding part  27  may be provided further to the side of the first aperture  25  instead of the center of the air flow path  23 , in other words, the part where said pair of translucent windows  24  is provided. Also, in this case, thinning of the air exhaled by the person being measured by the constant air [flow] mentioned above in the center of the air flow path  23  can be prevented. 
         [0041]    Also, in the airway adaptor  10  of this embodiment, said pair of translucent windows  24  may be provided at the inner wall located on the side of the air flow path  23 , that is to say, at the location along both sidewalls of the air flow path  23  during the use of said airway adaptor  10 . Dew condensation water generated inside the air flow path  23  by the air passing through air flow path  23 , or that has flown into the inside of the air flow path  23  from the outside, flows along the bottom wall of the air flow path  23 , so its contamination of the translucent windows  24  can be prevented by placing the translucent windows  24  as mentioned above. 
         [0042]    In the airway adaptor  10  of this embodiment, not only may the translucent windows  24  be placed as described above, as shown in  FIG. 5  to  FIG. 8 , but the partial shielding part  27  may also be provided so that it does not shield the lower side of the air flow path  23 . Therefore, said dew condensation water is not stopped at partial shielding part  27 , then will not accumulate inside the air flow path  23 , preventing it from contaminating the translucent windows  24 . 
         [0043]    In the airway adaptor  10  of this embodiment, partial shielding part  27  may be provided integrally with a tube  20 . Therefore, the partial shielding part  27  can be provided with the tube  20  without increasing the number of components. 
         [0044]    The partial shielding part  27  may be provided as a separate component from the tube  20 . By providing the partial shielding part  27  as a separate component, for example, when the person to be measured is an infant, who has a small exhaust breath pressure, the partial shielding part  27  can be installed at the tube  20 , as needed, when there is the need to allow the constant air flow to pass easily into the tube  20 . 
         [0045]    Regarding the airway adaptor  10  of this embodiment, without being limited to the configuration mentioned above, it may be configured so that it is connected to a respiratory concentration measurement device for measuring the concentration of a component acquired from a sample of breath from a person to be measured by, for example, the sidestream method. Specifically, it may be configured so that sampling of exhaled air from a person to be measured is possible by providing a sampling port at the center of the air flow path  23 , instead of providing a pair of translucent windows. 
         [0046]    In addition, the airway adaptor  10  may be configured to be a differential pressure-type flow rate measurement sensor, by providing pressure outlets for measuring the flow rate of the exhaled air to each respiratory-side adaptor  21  and patient-side adaptor  22  in the airway adaptor  10 , and placing a securing part inside the air flow path  23  between each pressure outlet. 
         [0047]      FIG. 9  is an enlarged sectional view showing an enlarged view in the proximity of the first aperture  25  of section C-C of  FIG. 6 . As shown in  FIG. 9 , in the airway adaptor  10  of this embodiment, the width of the cross section that cuts, in parallel, the partial shielding part  27  with the inner wall of the air flow path  23 , in other words, the length in the vertical direction in the cross section of the partial shielding part  27  as shown in  FIG. 9  is narrower in the second aperture  26  (left side of  FIG. 9 ) than in the first aperture  25  (right side of  FIG. 9 ). 
         [0048]    Forming the sectional structure of the partial shielding part  27  in such a shape can reduce the resistance that forms when the air current generated when exhausting the exhaled air from the person to be measured from airway adaptor  10 , in other words, the air current that passes from the left side to the right side in  FIG. 9  in the air flow path  23 , hits the partial shielding part  27 . 
         [0049]    The shape of the partial shielding part of the present invention is not limited to the shape of the partial shielding part  27  provided with the airway adaptor  10  of this embodiment. The airway adaptor  10  may be equipped with, for example, partial shielding parts  37 ,  47 ,  57 , and  67  having the shapes illustrated in  FIG. 10  to  FIG. 13 , instead of the partial shielding part  27 . Moreover, similarly to the partial shielding part  27 , these partial shielding parts  37 ,  47 ,  57 , and  67  are preferably provided closer to the side of the first aperture  25  than to the portion where a pair of translucent windows  24  was provided in the airway adaptor  10 . 
         [0050]    Note that the processing of information in the present invention may be performed by a processor that may include a computer-readable medium as known to those of ordinary skill in the art. 
         [0051]    While this invention has been particularly shown and described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.