Abstract:
A HME bypass system including a manually actuated bypass valve which is coupled into a respiratory air circuit, preferably upstream of the HME, to permit inspiratory air to be selectively passed through the HME, or to bypass the HME, depending upon the treatment desired by the healthcare provider.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates in general to respiratory therapy devices and, in particular, to a single patient use bypass for allowing a patient to receive aerosol delivery of medication by selectively bypassing a heat and moisture exchanger, an HME, positioned in a ventilator circuit without removing the HME from the ventilating circuit. 
     More specifically, but without restriction to the particular embodiment and/or use which is shown and described herein for purposes of illustration, this invention relates to a humidifying filter bypass which permits the introduction of medication from a metered dose inhaler (MDI) or nebulizer into a ventilator circuit containing an HME without necessitating the removal of the HME from the circuit. 
     2. Description of Related Art 
     As is known to those in the respiratory care field, HME&#39;s are humidifying filters which are frequently used in medical procedures, for example in ventilator circuits such as when intubating patients, to prevent deterioration of respiratory functions. These devices capture heat and moisture on expiration, and return it to the patient on inspiration. In certain of such usages it is also necessary to administer medication to the patient in the form of a mist or fine spray which is inhaled by the patient. 
     To this end it is preferable that the medication be administered to the patient without passing through the HME for more effective administration. Accordingly, heretofore the procedure has been to physically remove the HME from the respiratory circuit during the administration of the medication, and then to re-install the HME into the circuit after the medication has been administered. While such a procedure is effective in the administration of the medication, the procedure is time consuming and can result in the introduction of undesired contaminants into the respiratory circuit as a result of the removal and reinstallation of the HME whenever the patient is required to be medicated. Accordingly, it would be highly beneficial and much more efficient if such medication could be administered to the patient without necessitating that the HME first be removed from the circuit and then re-installed after administration. 
     The present invention provides such a device through the use of a manually actuated bypass valve which is coupled into a respiratory air circuit, preferably upstream of the HME, to permit inspiratory air to be selectively passed through the HME, or to bypass the HME, depending upon the treatment desired by the healthcare provider. In this manner medication from an MDI or nebulizer can be conveniently administered to a patient through the circuit without the removal and reinsertion of the HME into the circuit, or the HME can continue to function uninterrupted. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to improve the delivery of aerosol medications in respiratory care circuits. 
     Another object of this invention is to provide a single patient use HME bypass for a ventilator circuit. 
     Still another object of this invention is to provide a manually actuable bypass valve for a ventilator circuit to selectively direct inspiratory air through an HME or to bypass the HME as desired. 
     Yet another object of this invention is to provide a single patient use HME bypass to selectively couple an HME into a ventilator circuit or to selectively bypass the HME when administering aerosol medication. 
     These and other objects are attained in accordance with the present invention wherein there is provided an HME bypass for use in respiratory therapy for selectively passing air through the HME or selectively bypassing the HME as determined by the healthcare provider. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     Further objects of this invention, together with additional features contributing thereto and advantages accruing therefrom, will be apparent from the following description of a preferred embodiment of the present invention which is shown in the accompanying drawings with like reference numerals indicating corresponding parts throughout and which is to be read in conjunction with the following drawings, wherein: 
     FIG. 1 is a frontal perspective view of the HME bypass system; 
     FIG. 2 is an exploded view of the HME bypass system to better illustrate the parts of the device and the components thereof; 
     FIG. 3 is an enlarged cross sectional view of a manually actuable valve used in the invention to better illustrate the structure for selectively bypassing the HME; 
     FIG. 4 is a frontal perspective view of an adapter than can be included in the circuit to facilitate the introduction of aerosol medication; 
     FIG. 5 is an enlarged cross sectional view of the adapter illustrated in FIG. 4 to better illustrate the internal construction thereof; and 
     FIG. 6 is a frontal perspective view of the adapter illustrated in FIG. 4 inserted into the circuit of the apparatus illustrated in FIG.  1 . 
     This and additional embodiments of the invention may now be better understood by referring to the following detailed description of the invention wherein the illustrated embodiment is described. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Throughout this description, the preferred embodiment and examples shown should be considered as exemplars, rather than limitations on the apparatus and methods of the present invention. 
     Referring now to the drawings, there is shown in FIGS. 1 and 2, an HME bypass system  100  for selectively controlling the use or bypassing of a heat and moisture exchanger (HME)  20  in a breathing or respiratory circuit such as a ventilator circuit. As is known to those skilled in the art, a ventilator circuit is used to assist or facilitate a patient&#39;s breathing, such as in post surgical procedures, and to this end may employ an HME to capture heat and moisture upon the patient&#39;s expiration of air, and return it to the patient upon inspiration, thereby preventing deterioration of respiratory functions. HME&#39;s are available from a number of medical supply houses, and are generally of different sizes. However, all HME&#39;s have coupling portions  21  and  22  of a size, preferably 22 mm. and 15 mm., such that they can be connected into an air-flow circuit, such as into the tubing used in a ventilator circuit. The HME bypass system  100 , couples the HME  20  into the air-flow circuit and provides a bypass to permit air flow around the HME, when desired, under the control of a manually actuable air-flow control valve  10 , preferably positioned in the air-flow circuit upstream of the HME  20 . 
     The air-flow control valve  10  includes a “Y” shaped coupling forming a discharge outlet  11  through which air flow is passed either to the HME  20 , through a discharge outlet  11   a , or when it is desired to bypass the HME  20 , through a discharge outlet  11   b . The air flow is thereafter passed through the remainder of the air-flow circuit. Preferably a flexible HME bypass air-flow tube  30  is coupled at an inlet end  31  to the air-flow control valve discharge outlet  11   b , and extends a length sufficient to bypass the HME  20 . A discharge end  32  of the air-flow tube  30  is coupled to a bypass inlet  41   b  of a second “Y” shaped coupling  40  forming an inlet to return the bypassed air to the air-flow circuit. A second inlet  41   a  of the “Y” shaped coupling inlet  40  is connected to the outlet  22  of the HME  20  to provide an inlet to receive air passed through the HME to couple the air passed therethrough into the air-flow circuit. A discharge outlet  42  is formed on the downstream end of the second “Y” shaped coupling  40  to connect the HME bypass system  100  into the air-flow circuit. 
     Referring now to FIGS. 2 and 3, the air-flow control valve  10  is a manually actuable two-position valve for discharging air received through an inlet port or opening  1  into either the HME  20 , through the control valve discharge outlet  11   a , or the HME bypass, through the control valve discharge outlet  11   b . To this end the control valve is formed with a circular-shaped base  9  having formed therethrough a pair of openings  9   a  and  9   b  which are aligned, respectively, to pass air through the discharge outlets  11   a  and  11   b . The opening and closure of the two openings  9   a  and  9   b  is effected by the rotational movement of a control plate  7  which is rotatably supported in sealing engagement with the base  9  to mutually exclusively selectively align an aperture  7   c  formed in the control plate  7  with the openings  9   a  and  9   b  formed in the valve base  9 . A stop pin  9   c  is carried by the valve base  9  and extends outwardly therefrom to pass through a motion limiting opening  7   d  formed in the control plate  7 . The stop pin  9   c  limits the rotational movement of the control plate  7  between stop positions  7   a  and  7   b , whereat the post  9   c  will become engaged with one of the stop positions  7   a  or  7   b  to align the aperture  7   c  with one of the openings  9   a  or  9   b , respectively. A decorative ring  5  and cover  4  connect the portions of the air-flow valve  10  together, and an indicator  3 , carried on the cover  4 , provides visual and tactile indicia in combination with the decorative ring  5  as to the alignment of the aperture  7   c  with the openings  9   a  and  9   b  in the valve base  9 . In this manner it may be determined through the indicator  3  if the air-flow control valve  10  is positioned to pass air flow through the HME  20  or to pass the air flow through the HME bypass tube  30 . 
     Referring now to FIGS. 4-6, there is illustrated a medication coupling  50  for connection into the HME bypass system  100 , and the coupling  50  connected to the discharge outlet  11   b  of the air-flow control valve  10  to facilitate the use of a pressurized medication dispensing cannister such as the type used with a metered dose inhaler (MDI) or a nebulizer with the HME bypass tube  30  to conveniently introduce medications into the air-flow circuit. The medication coupling  50  includes an inlet  51  sized for connection to the discharge outlet  11   b  of the air-flow control valve  10 , and an outlet  52  sized for connection to the inlet  31  of the HME bypass tube  30 . An upper flat or planar portion  53  is formed with an aperture or medication port  55  of a size and type for receiving therein the discharge outlet of a pressurized medication dispensing canister (not shown) of the type used with an MDI to provide an opening through which such medication can be dispensed through the HME bypass tube  30  into the air-flow circuit. When a pressurized medication dispenser canister is used to dispense medication into the HME bypass tube  30 , a closure cap  66 , secured to the medication coupling  50  by a tether strap  67 , is applied to an opening  56  on the side of the medication coupling  50  opposite to the aperture or port  53  to form a closure thereof so that the air flow through the medication coupling is from the inlet  51  through the outlet  52  to carry the medication dispensed into the medication coupling through the HME bypass tube  30 . 
     The opening  56  in the medication coupling  50  is sized to receive and be connected to a standard nebulizer (not shown), so that medication which is desired to be introduced into the air flow by the use of a nebulizer can be conveniently administered. To this end a second closure  68 , connected to the medication coupling  50  by a second tether  69 , is applied to the aperture  55  and/or the planar portion  53  to close the opening so that the air flow through the medication coupling  50  is from the inlet  51  to through the outlet  52  to carry the medication through the HME bypass tube. While the medication coupling  50  is illustrated as being connected into the HME bypass system  100  at the discharge outlet  11   b  of the air-flow control valve  10 , it is to be understood that the medication coupling can be connected to the inlet  1  of the air-flow control valve  10  if desired. 
     While this invention has been described in the specification and illustrated in the drawings with reference to preferred embodiments, the structures of which have been disclosed herein, it will be understood by those skilled in the art to which this invention pertains that various changes may be made, and equivalents may be substituted for elements of the invention without departing from the scope of the claims. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed in the specification and shown in the drawings as the best mode presently known by the inventors for carrying out this invention, nor confined to the details set forth, but that the invention will include all embodiments, modifications and changes as may come within the scope of the following claims: