Abstract:
An access port closure valve for use with a respiratory support system is provided. The access port closure valve has a sealing member that has a first and second sealing lip. The sealing lips are elongated and are parallel to one another. The sealing lips are at least partially cylindrical in shape and are urged against one another to form a seal that has a taper. An elongated cylindrical frame substantially surrounds the sealing member. The sealing lips are disposed transversely across an end of the frame. The frame is configured to engage the respiratory support system. The sealing member seals the frame and accommodates passage of a surgical instrument through the valve.

Description:
TECHNICAL FIELD  
         [0001]    This invention relates generally to a respiratory support system, and more particularly to an access port closure valve for use with a respiratory support system.  
         BACKGROUND  
         [0002]    Respiratory support systems are frequently used for the ventilation of critically ill patients. In most instances, the respiratory support system includes an artificial airway such as a tracheal tube positioned either directly in the trachea or through the nose or mouth into the trachea of a patient. A multi-port manifold is connected to the tracheal tube at one port position of the manifold. A source of oxygen is connected to the manifold at a second port thereof. The respiratory support system assists the patient in maintaining adequate blood oxygenation levels without straining the patient&#39;s heart and lungs.  
           [0003]    Because the patient can no longer clear his or her airway through coughing and other natural functions, it is periodically necessary to aspirate fluids from the patient&#39;s trachea or lungs. In the past, in order to accomplish aspiration within certain types of respiratory systems, it has been necessary to disassemble part of the respiratory system by removing the ventilator manifold or by opening a port in the manifold and inserting a small diameter suction catheter tube down the tracheal tube and into the patient&#39;s trachea and lungs. The fluid is suctioned from the patient, the suction catheter is removed, and the respiratory support system is reassembled.  
           [0004]    However, due to the interruption of respiratory support during this procedure, a patient&#39;s blood oxygen level could drop to an unacceptable level. One solution to this problem is to provide a ventilator or manifold that has an access port that is normally sealed but through which a suction catheter could be inserted. Such an access port allows for the insertion of a catheter and aspiration of the patient without a drop in positive end expiratory pressure (PEEP). Once aspiration of the patient is complete, the catheter can be removed from the tracheal tube and manifold without having to detach or reassemble the manifold. This is because the access port will seal automatically once the catheter is removed. Such an access port is described in U.S. Pat. No. 4,351,328 issued to Bodai.  
           [0005]    The present invention is an improvement on access ports that allow for the aspiration of patients without a drop in PEEP.  
         SUMMARY  
         [0006]    Objects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned from practice of the invention.  
           [0007]    The present invention provides for an improved sealing port on a manifold that can be used with not only a catheter, but with other respiratory instrumentation. Examples of such include lavage and instrumentation to monitor and view the tracheal and respiratory path.  
           [0008]    The access port closure valve according to the invention includes a sealing member having a first and second sealing lip. The sealing lips may be elongated and are parallel to one another. The sealing lips are at least partially cylindrical in shape and are urged against one another to form a tapered seal.  
           [0009]    The access port closure valve may also include an elongated cylindrical frame that substantially surrounds the sealing member, the first and second sealing lips disposed transversely in the cylindrical frame. The frame is configured to engage the respiratory support system. The sealing member seals the frame, and the frame accommodates passage of a surgical instrument through one end of the frame to the other.  
           [0010]    The present invention also encompasses a respiratory support system that includes a manifold having at least one port. An access port closure valve engages the port on the manifold and may include a sealing member as discussed above. Also, the access port closure valve may include an elongated frame as discussed above, wherein the frame is configured to engage the manifold port.  
           [0011]    Alternatively, the above-identified embodiments of the present invention can further include a plurality of biasing members. These biasing members may be located on each sealing lip and contribute to the at least partially cylindrical shape of the first and second sealing lips.  
           [0012]    In one embodiment of the access port closure valve, the sealing member and the elongated cylindrical frame are a single integral part and are made from the same material.  
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a perspective view of an access port closure valve of the present invention incorporated with a manifold that is used in a respiratory support system.  
         [0014]    [0014]FIG. 2 is a perspective view of an access port closure valve of the present invention positioned on a T-shaped ventilator manifold that is used on a respiratory support system.  
         [0015]    [0015]FIG. 3 is a perspective view of an access port closure valve of the present invention.  
         [0016]    [0016]FIGS. 4A and 4B are cross sectional views of an alternate embodiment of an access port closure valve of the present invention. FIG. 4A shows the access port closure valve in a closed sealed position and FIG. 4B shows the valve in a closed sealed position with a suction catheter inserted therethrough.  
         [0017]    [0017]FIG. 5 is a perspective and cross-sectional view of the access port closure valve of FIG. 3 showing a cut along line A-A of FIG. 3. 
     
    
     DETAILED DESCRIPTION  
       [0018]    Reference will now be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not meant as a limitation of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a third embodiment. It is intended that the present invention include these and other modifications and variations.  
         [0019]    Referring now to the drawings, FIG. 1 shows an access port closure valve, generally  20 , for use with a respiratory support system. The access port closure valve  20  is shown attached to a manifold  22  of a ventilation circuit. The manifold  22  has an aspiration and ventilation port  24  that is attachable to the proximal end of a tracheal tube (not shown), and a ventilation port  26  that is attachable to a source of respiratory air. Various types and configurations of respiratory system manifolds are known to those skilled in the art and a detailed description of the construction and operation of the manifold  22  is not necessary for an understanding of the closure valve  20 . The manifold  22  has a rotatable member  28  that can move the first access port  25  and the second access port  30  into and out of alignment with the aspiration and ventilation port  24 . The manifold  22  shown in FIG. 1 is described in detail in commonly owned U.S. Pat. No. 5,735,271 incorporated herein by reference in its entirety for all purposes.  
         [0020]    The access port closure valve  20  is shown attached to the first access port  25 . Bronchoscopes, catheters, sensor devices, or other medical instruments can be introduced into the airway of a patient by insertion through the access port closure valve  20 , the first access port  25 , and then through the aspiration and ventilation port  24 . The manifold  22  is provided with the second access port  30  shown in a closed position in FIG. 1. Upon rotation of the manifold  22 , the second access port  30  can be moved into an open or aligned position with respect to the port  24  and access to the tracheal path can now be obtained through the second access port  30 . It is to be understood that the access port closure valve  20  can be used on either or both first access port  25  or second access port  30  and such embodiments are considered to be within the scope of the present invention.  
         [0021]    The use of the access port closure valve  20  on the manifold  22  prevents a drop in PEEP because the manifold  22  is sealed before, during, and after insertion of a medical instrument into the airway of a patient through the valve. The use of the access port closure valve  20  also reduces contamination to and from a patient.  
         [0022]    [0022]FIG. 2 shows a T-shaped manifold  32  with an access port  34  located in its elbow section. An access port closure valve  20  is shown attached to the access port  34 . An aspiration and ventilation port  38  is attachable to a proximal port of an endotracheal tube or tracheostomy tube (now shown). Medical instruments such as bronchoscopes, catheters, sensor devices, or other medical instruments may be introduced to the patient through the access port closure valve  20 , access port  34 , and then through the aspiration and ventilation port  38 . The T-shaped manifold  32  also has a ventilation port  36  attachable to a source of respiratory air.  
         [0023]    It is to be understood that the access port closure valve  20  can be used on various manifolds known in the prior art, and not just those illustrated in the disclosed description.  
         [0024]    The access port closure valve  20  is shown in greater detail in FIG. 3. The access port closure valve  20  has a first end  46  that is frictionally fit onto the access port  34  in FIG. 2, and first access port  25  in FIG. 1. Such a frictional attachment also allows for the access port closure valve  20  to be readily removable from the access ports. However, it is to be understood that other forms of attachment known in the art may be used to attach the access port closure valve  20  onto the manifold  22 . These could include, for instance, clips, adhesives, or sonic welding. The access port closure valve  20  also has a second end  44 , which has an opening  48 . Instrumentation is moved through the opening  48  of the second end  44 , then through the access port closure valve  20 ,and exits the first end  46 . A sealing member  49  is located within the opening  48 . The access port closure valve  20  is provided with a cellular area  40  and a plurality of ribs  42 . The purpose of these two features is to help shape the sealing member  49 , improve the seal of the access port closure valve  20 , strengthen the access port closure valve  20 , and also provide for a surface with which to possibly attach other ports or instruments to the access port closure valve  20 .  
         [0025]    [0025]FIG. 5 shows the access port closure valve  20  of FIG. 3 with a cut along line A-A of FIG. 3 and illustrates how the sealing member  44  is constructed when the access port closure valve  20  is molded as a single integral piece element. It is to be understood that the first end  46  and second end  44  are all a single integral piece, the cut out being necessary to show the detail of the plurality of ribs  42  and cellular area  40 .  
         [0026]    [0026]FIG. 4A shows a cross-section of an access port closure valve  20  in accordance with the present invention and illustrates the operation of sealing member  49 . A frame  60  is included and may be formed from any suitable rigid or semi-rigid material. The sealing member  49  is embedded within the frame  60  and includes a first sealing lip  50  and a second sealing lip  52 . The first sealing lip  50  and second sealing lip  52  are shown having a U-shaped cross-section in FIG. 4A. However, it is to be understood that the first sealing lip  50  and second sealing lip  52  do not need to be of an exact circular cross-section. Other cross-sectional shapes are to be considered within the scope of the present invention. For instance, the lips  50  and  52  could be partially or fully cylindrical, as well as tubular and hollow.  
         [0027]    [0027]FIG. 4A shows the first sealing lip  50  and the second sealing lip  52  in a closed position before the insertion of a suction catheter  62 . It is to be understood however, that the access port closure valve  20  could be used with a different surgical instrument that is either semi-flexible, flexible, or rigid. The first sealing lip  50  and second sealing lip  52  define a pair of hollow cavities  57  and  55  respectively. Cavities  57  and  55  will change shape as the lips  50  and  52  are deformed as in FIG. 4B. The first sealing lip  50  and second sealing lip  52  are provided with a first sealing lip curved surface  54  and a second sealing lip curved surface  56 . The first sealing lip curved surface  54  and second sealing lip curved surface  56  face one another and are urged into contact with one another in the closed position of sealing member  49 . The curvature of the first sealing lip curved surface  54  and the second sealing lip curved surface  56  form a taper and a nip line  70  at the point of contact between the lips. The taper aids in the insertion of instruments into the access port closure valve  20 .  
         [0028]    The first sealing lip  50  and second sealing lip  52  are parallel to one another in orientation. A seal  58  is formed along the nip line between the first sealing lip curved surface  54  and the second sealing lip curved surface  56 . As shown in FIG. 4A, seal  58  is a planar surface seal as opposed to a simple line seal along nip line  70 . This is because the first and second sealing lips  50  and  52  are formed from a material capable of enough deformation to achieve a longitudinally extending planar seal. However, an embodiment of seal  58  being a line seal is to be considered within the scope of the present invention.  
         [0029]    [0029]FIG. 4B shows a suction catheter  62  being inserted between the first sealing lip  50  and the second sealing lip  52  through the body of the access port closure valve  20 . Insertion of the catheter  62  causes the sealing lips  50  and  52  to deform at locations  64  and  66  next to the insertion point of the suction catheter  62 . The elastomeric properties of the sealing lips  50  and  52  cause the lips to separate and conform to the shape of the suction catheter  62  such that a seal  58  is formed about the suction catheter  62  as it is inserted between the sealing lips  50  and  52 . Removal of the suction catheter  62  causes the first sealing lip  50  and the second sealing lip  52  to reform to the orientation shown in FIG. 4A.  
         [0030]    It is to be appreciated that a retainer configuration such as the cellular area  40  and plurality of ribs  42  can be used on either one or both first sealing lip  50  and/or second sealing lip  52 . Such embodiments are to be considered within the scope of the present invention. However, it is not necessary that sealing member  49  have the configuration of ribs  42  and cellular area  40  in order for the sealing member  49  to function.  
         [0031]    The material used for the first sealing lip  50  and second sealing lip  52  is elastomeric and has exceptional shape memory to recover from the insertion of a device. For example, materials that could be used for the first sealing lip  50  and second sealing lip  52  include: styrenic thermoplastic elastomers, flexible polyvinyl chlorides (fPVC), and polyether block amide (a flexible nylon). The rest of the access port closure valve  20  can be made of these materials as well or a more rigid material.  
         [0032]    The embodiment shown in FIG. 3 and FIG. 5 shows the first sealing lip  50  and the second sealing lip  52  formed integrally with the frame  60 . The entire access port closure valve  20  is a single integrally molded part being made of the same material. It is to be understood that the first sealing lip  50  and second sealing lip  52  could be separate parts that are adhered to the walls of the frame  60  (for instance by sonic welding) or otherwise attached so that only the lips  50  and  52  are moveable relative to one another. The access port closure valve  20  can therefore be formed through various processes such as injection molding, material deposition, casting of thermoplastics or thermosets, or by multi-part assembly.  
         [0033]    The access port closure valve of the present invention can be formed or permanently fixed in a respiratory support system, for example as a permanent component of an access port on respiratory support system manifold. The closure valve may also be provided as a separate component removably attachable to the manifold or other component on a respiratory support system.  
         [0034]    It should understood that the invention includes various modifications that can be made to the embodiments of the access port closure valve described herein as come within the scope of the appended claims and their equivalents.