Abstract:
A multilumen tracheal tube or catheter is disclosed. The tube has a plurality of ingress and egress lumens, each having a suction or discharge port as appropriate. At least one rotatable collar is provided. The collar overlaps each port and is capable of selecting various combinations of suction and discharge ports without increasing the likelihood of cross contaminating any others.

Description:
BACKGROUND 
     The present invention relates to a tracheal tube used for mechanical ventilation of a hospital patient, by insertion of the tube into the trachea of the patient. In particular, the present invention relates to a tracheal tube having means for irrigating and/or evacuating contaminated fluids accumulating above the tracheal tube cuff and thereby reducing the risk of such contaminated fluids entering the lungs of the patient. 
     Tracheal intubation involves the insertion of a tubular device, known as a tracheal tube, into the trachea of a patient. The tracheal tube passes through the trachea and terminates at a position above the carina, anterior to a position between the second and fourth thoracic vertebrate. Gases may then be introduced through the tracheal tube and into the lungs of the patient. 
     The primary purposes of tracheal intubation, are to mechanically ventilate the patient&#39;s lungs, when a disease prevents the patient from normal, breathing induced ventilation, or to apply anesthetic gases during surgical intervention. In order to create enough air pressure to accomplish such mechanical ventilation and to prevent escape of gases past the tube, it is necessary to seal the passageway around the tracheal tube. A seal may be produced by the use of an inflatable cuff formed integrally with and surrounding the tracheal tube. When the tracheal tube has been introduced into the patient&#39;s trachea, the inflatable cuff will normally be located about 3 to 5 centimeters above the carina and within the tube-like trachea. 
     The inflatable cuff is then inflated so as to engage the wall of the trachea and thereby seal the trachea and prevent gases being introduced through the tracheal tube from simply backing up around the tube. While treatment of this sort has proved successful for patients having chronic or acute respiratory diseases, there is a constant risk of several complications. 
     In particular, many patients receiving tracheal intubation develop pneumonia, resulting from an infection of the lungs, possibly induced by contaminated, pooled fluids entering the trachea and the lungs after bypassing the epiglottis during intubation. The fluids may be in the form of saliva, blood, secretions, food and stomach contents, even medications. The epiglottis normally operates as a valve which selectively closes the entry into the trachea and lungs, to prevent the introduction of secretions and particulate matter. However, when a tracheal tube is in place, the epiglottis is held in an open position, and secretions which would normally be directed away from the trachea and into the digestive system, instead follow the path of the tracheal tube and pool above the inflatable cuff of the tracheal tube. 
     The greatest risk of such infectious fluids reaching the lungs is aspiration of these fluids past the tracheal tube cuff during the mechanical ventilation episode. An additional risk in particular is when the need for endotracheal intubation ends, the inflatable cuff of the endotracheal tube is deflated so that the endotracheal tube may be withdrawn, the infectious fluids which have accumulated above the inflatable cuff are released and flow freely into the lower airway where bronchitis and pneumonia may rapidly develop. 
     To overcome these risks, it is known in the prior art to combine a single lumen suction tube with a tracheal tube. The suction tube is joined to the tracheal tube in a suitable manner, the end of the suction tube terminating at a position above the inflatable cuff. The suction tube provides means for suction or evacuation of any pooled secretions which accumulate in the trachea above the inflatable cuff. However, such prior art devices have the disadvantage that use of a single lumen for the suction tube often causes direct suction to be exerted on the tracheal mucosa which may then result in damage to the mucosa. 
     U.S. Pat. No. 4,840,173 to Porter III, describes an endotracheal tube having a single lumen suction tube merged thereto. In particular, this patent describes a device wherein the suction tube is laminated to the outside of the ventilation tube, so that the suction tube terminates at a position just above the inflatable cuff. The suction tube includes multiple openings which may be used to evacuate secretions which pool above the inflatable cuff. In addition, the inflatable cuff includes a section immediately adjacent to the end of the suction tube that is less flexible than the rest of the inflatable cuff, to insure that the flexible material of the inflatable cuff is not sucked up against the suction tube openings. The endotracheal tube described in the Porter III patent has the disadvantages noted above, that the single lumen suction tube may exert suction on the tracheal mucosa and thereby cause damage to the mucosa. Further, the Porter III device is of a relatively complex design, requiring difficult processing, resulting in expensive production. 
     U.S. Pat. No. 5,143,062, issued to Peckham, discloses an endotracheal tube comprising a double lumen through which air may be circulated, creating an indirect gentle suction through a suction eye communicating with the distal ends of the lumens, and located at a position proximal to the inflation cuff. This design, however, does not provide adequate suction necessary for aspirating secretions and is easily occluded. 
     The above noted patent references fail to adequately address the suctioning of secretions which have pooled above the inflatable cuff in a manner that is sufficient to accomplish the task but is not so strong so as to cause damage to the mucosa. Moreover, these references and other conventional endotracheal and tracheal tubes lack the ability to suction both these secretions, even when a patient is turned according to nationally instituted decubitus prevention protocols. That is, they fail to provide alternative suction capabilities in the event the patient is turned or in the event the desired suction lumen is occluded by secretions. 
     As the background devices fail to disclose a tracheal tube and suction catheter system having these structural characteristics, the need for such a device is apparent. The instant invention addresses this by providing a multilumen tracheal tube and suction catheter system comprising a device that enables the surgical team to direct suctioning to any number of lumens within the tracheal tube. 
     SUMMARY OF THE INVENTION 
     The present invention improves upon a tracheal tube. In one embodiment, a tracheal tube is provided having a cannula that in turn has a distal end and a proximal end. The cannula has at least one ingression lumen within the cannula having a suction port, the suction port is located distal from the proximal end. Also, the cannula has at least one egression lumen within the cannula in non-communication with the at least one ingression lumen, the at least one egression lumen has a discharge port, the discharge port is also located distal from the proximal end. An inlet for introducing an externally applied therapeutic agent or method is provided in the at least one ingression lumen and an outlet for egress of fluids is provided from the at least one egression lumen. In some embodiments, the cannula is made up of a first wall and a second wall which is concentric to the first wall. The first wall surrounds and defines a ventilation lumen which is adjacent a first surface. The first wall is attached at a second surface to a first surface of the second wall by at least two partitions. The at least one ingression lumen is defined by the second surface of the first wall, the first surface of the second wall, and the first surfaces of the at least two partitions. The at least one egression lumen is defined by the second surface of the first wall, the first surface of the second wall, and the second surfaces of the at least two partitions. 
     In these embodiments, a collar surrounding the cannula and overlapping each inlet and outlet is provided. The collar is positionable so as to selectively enable and disable fluid communication through each lumen between its port and its inlet or outlet. In some embodiments, two collars are provided. A first collar surrounding the cannula and overlapping the inlet, and a second collar surrounding the cannula and overlapping the outlet is provided. Each collar is positionable so as to selectively enable and disable fluid communication through each lumen between its port and its inlet or outlet. An inflatable cuff surrounding the cannula at the distal end is also provided. The inflatable cuff is adapted to seal the trachea of a patient, the inlet and outlet being proximal to the inflatable cuff. 
     In another embodiment, a tracheal tube is provided. The tracheal tube has a cannula having a distal end and a proximal end. A plurality of ingression lumens are provided within the cannula, each having a suction port located distal from the proximal end and an inlet located proximal to the proximal end. A plurality of egression lumens are also provided within the cannula, each having a discharge port located distal from the proximal end and an outlet located proximal to the proximal end. Each ingression lumen is maintained in fluid non-communication with each egression lumen so as to minimize cross-contamination of any ingression lumen with any egression lumen. A user manipulable selector is provided for selectively enabling and disabling fluid flow through at least one of an ingression lumen, at least one of an egression lumen, or both. The user manipulable selector may be a rotatable collar rotatably affixed to the cannula and overlapping all of the inlets and outlets. The collar itself would contain a first and a second port therethrough. Rotation of the collar aligns the first port with the inlet of a user selected ingression lumen while automatically aligning the second port with the outlet of a corresponding egression lumen. In many embodiments, a guide is coupled to the cannula. the guide overlaps all of the inlets and outlets and has openings aligned with each inlet and outlet. The collar is rotationally attached to the guide. In each embodiment having a guide, a fluid tight seal is provided between the collar and the guide. 
     In other embodiments, the user manipulable selector is configured as a first and a second rotatable collar. Each is rotatably affixed to the cannula, the first collar overlapping all of the inlets, and the second collar overlapping all of the outlets. Each collar has at least one port therethrough, wherein rotation of the first collar aligns the at least one port with the inlet of a user selected ingression lumen and rotation of the second collar aligns the at least one port with the outlet of a user selected egression lumen. For this embodiment, a guide may be coupled to the cannula overlapping all of the inlets and outlets. The guide would have openings aligned with each inlet and outlet, the first and second collar would be rotationally attached to the guide. In alternative embodiments, a first and a second guide may be coupled to the cannula. The first guide would for example overlap all of the inlets, and the second guide would overlap all of the outlets. Each guide would be provided with openings aligned with each inlet and outlet respectively. The first collar would be rotationally attached to the first guide and the second collar would be rotationally attached to the second guide. 
     In each embodiment the ingression lumen would enable the introduction of an externally applied therapeutic agent or method to be introduced into a patient within which the tracheal tube is placed. The egression lumen would enable the suctioning of fluids from a patient within which the tracheal tube is placed. Additionally, a ventilation lumen would be provided. In many embodiments, the ingression and egression lumens would be radially disposed about an outer diameter of the ventilation lumen. An inflatable cuff surrounding the cannula at the distal end adapted to seal the trachea of a patient would be provided in many embodiments as well. The inlets and outlets of the cannulas would be proximal to the inflatable cuff. Moreover an inflation lumen for selectively inflating and deflating the inflatable cuff would be provided. 
     Other objects, advantages and applications of the present invention will be made clear by the following detailed description of a preferred embodiment of the invention and the accompanying drawings wherein reference numerals refer to like or equivalent structures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is diagrammatic illustration of one embodiment of a multilumen catheter placed within a patient in accordance with the present invention; 
         FIG. 2  is an isometric view of the  FIG. 1  multilumen catheter in a straightened configuration; 
         FIG. 3  is a cutaway of the  FIG. 1  multilumen catheter viewed through the axial centerline of the multilumen catheter so as to depict the passages therethrough; 
         FIG. 4  is a diagrammatic illustration of an alternative embodiment of the  FIG. 1  multilumen catheter so as to depict the passages therethrough; 
         FIG. 5  is a cutaway of yet another alternative embodiment of the  FIG. 1  multilumen catheter viewed through the axial centerline of the multilumen catheter so as to depict the passages therethrough; 
         FIG. 6  is partial cutaway of yet another embodiment of the  FIG. 1  multilumen catheter depicting one possible port configuration; 
         FIG. 7  is an isometric view of an alternative embodiment of the  FIG. 1  multilumen catheter in a straightened configuration; and 
         FIG. 8  is a side cutaway of the  FIG. 1  multilumen catheter viewed through the radial centerline of the multilumen catheter, perpendicular to the  FIG. 3  depiction, so as to depict the guide and collar. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made to the drawings in which the various elements of the present invention will be given numeral designations and in which the invention will be discussed so as to enable one skilled in the art to make and use the invention. It is to be understood that the following description is only exemplary of the principles of the present invention, and should not be viewed as narrowing the pending claims. Those skilled in the art will appreciate that aspects of the various embodiments discussed may be interchanged and modified without departing from the scope and spirit of the invention. 
     Referring to  FIG. 1 , a tracheal tube  12  is depicted extending through the mouth  14  and the trachea  16  of the upper respiratory system of patient  10 . The tracheal tube  12  terminates in a distal end  18  well above the point  20  at the first bifurcation of trachea  16  into the right lung  22  through the right mainstem bronchus  24  and into the left lung  26  through the left mainstem bronchus  28 . Typical sub-branchings of the mainstem bronchus are shown in  FIG. 1  for illustrative purposes in relation to the sub-branching of left mainstem bronchus  24  into left lung  26 . 
     The distal end  18  of tracheal tube  12  is provided with a balloon  30  which, when inflated, engages the walls of trachea  16  to facilitate mechanical ventilation of patient  10  through a connector  32  coupled to a standard tracheal tube adapter  34  at the proximal end  36  of tracheal tube  12 . As would be understood by those of skill in the art, air from the ventilating apparatus for patient  10  enters tracheal tube  12  through one leg of the connector  32 , and correspondingly, air is returned to the ventilating apparatus from patient  10  through a second leg of the connector. 
     Looking now to  FIG. 2 , a more detailed view of the tracheal tube  12  may be had. This view depicts the tube  12  in a straightened configuration. A collar  38  is positioned on the tube  12 . The collar  38  partially rotates about the tube or cannula and provides the user or medical personnel with an ability to select functionalities as explained in greater detail below. 
     A plurality of suction ports  40  are provided at desirable locations along the tube  12 . In some embodiments, a portion of the suction ports  40  are located above the balloon  30 , i.e., between the balloon  30  and the proximal end  36 , while another portion are located below the balloon  30 , i.e., between the balloon  30  and the distal end  18 . Some embodiments may have suction ports  40  on only one side of the balloon  30 . Likewise, a plurality of discharge ports  41  are also provided at desirable locations along the tube  12 . In some embodiments, a portion of these discharge ports  41  are also located above the balloon  30 , while another portion are located below the balloon  30 . Similarly, in some embodiments the discharge ports  41  may be located on only one side of the balloon  30 . 
     As shown in  FIG. 3 , the tube  12  is configured as a cannula with a plurality of internal lumens that extend at least partially along the length of the tube  12 . In the  FIG. 3  example, a ventilation lumen  42  is provided at the center of the tube  12 . Surrounding the ventilation lumen  42  is a plurality of lumens, including ingression lumens  44  and egression lumens  45 . Many embodiments, such as the  FIG. 3  embodiment contain a plurality of such lumens  44  and  45  arranged radially about the ventilation lumen  42 . A first wall  46  separates the ventilation lumen  42  from each lumen  44  and/or  45 . In this embodiment, a second wall  48  forms the exterior wall of the tube  12 . A plurality of partitions  50  are provided to separate each lumen  44  and  45  from one another. Each of these walls and partitions may be created via extrusion of the material comprising the tube through an appropriate die during formation of the tube  12  and as such may effectively be considered as a single component having a plurality of lumens situated therein. In any event, the placement of lumens in a tracheal tube is a process that would be understood by those of skill in the art 
     As seen in  FIG. 3 , additional lumens, for example an inflation lumen  52 . The inflation lumen  52  connects the balloon  30  to some means capable of inflating the balloon, thus keeping the tracheal tube  12  adequately sealed and positioned desirably within the trachea  16 . It may be seen in this FIG. that the ingression lumens  44  are arranged in a group. Likewise the egression lumens  45  are arranged in a group as well. This is so the collar  38  can align one ingression lumen  44  with one predesignated and corresponding egression lumen  45 . As such, the collar  38  is capable of rotating approximately about 180 degrees about the tube  12 . A guide  54  may also be provided within which the collar  38  is allowed to rotate. 
     Looking in more detail at  FIG. 3 , it can be seen that there are four ingression lumens, designated  44   a - d  and four corresponding egression lumens, designated  45   a - d  respectively. Each of these lumens is diametrically opposed to a corresponding counterpart, that is, lumen  44   a  is diametrically opposite lumen  45   a , and so on. It should be understood that this labeling is meant only to illustrate that in this embodiment, for every ingression lumen  44  there is a corresponding egression lumen diametrically opposite one another. 
     Turning now to an alternative embodiment as shown in the cross-sectional view labeled  FIG. 4 , it may be seen that there are a total of six positions over each hemisphere of the tube  12 . Each position is designated P 1  though P 6  respectively. Of course there may be more or less than six positions, the embodiment illustrated is simply meant to illustrate the concept in principle. Therefore, looking at each in turn it may be seen that the first position, or P 1 , contains the inflation lumen  52  and no corresponding ingression lumen or egression lumen  44  or  45  respectively. P 2  contains egression lumen  45   d  but no corresponding ingression lumen. Positions P 3 , P 4 , and P 5  contain each of a corresponding ingression lumen  44   a  and  45   a ,  44   b  and  45   b , and  44   c  and  45   c  respectively. P 6 , similar to P 1  contains an ingression lumen  44   d , but no corresponding egression lumen. 
       FIG. 5  illustrates a partial cutaway view of the  FIG. 4  embodiment. In this FIG., the collar  38  is also depicted, and together with the following description it should be evident to one skilled in the art as to the manner in which the device functions. As shown, the ingression and egression lumens  44  and  45  are radially disposed about the ventilation lumen  42 . Each ingression lumen  44  contains an inlet  56 , whereas each egression lumen  45  contains an outlet  58 . The collar  38  has a dedicated conduit  60  for the ingression lumens  44  as well as a second dedicated conduit  60  for the egression lumens  45 . Each conduit  60  is used to pass fluids into the patient  10  via ingression lumens  44 , or to extract fluids from the patient  10  via egression lumens  45 . Each conduit has a passage  62  leading from a point adjacent the second wall  48  to a point distal from the second wall. Rotating the collar  38  about the tube  12  selectively aligns the passage  62  within each conduit  60  with a specific ingression lumen  44  and its corresponding egression lumen  45  thus enabling flow into or out of the specific lumen as appropriate so that it may accomplish its intended function. 
     Looking at each position, P 1  through P 6 , provides one with a better understanding of this particular embodiment of the invention. It may be seen that rotating the collar  38  so that the passages  62  in the conduits  60  are positioned at P 1  effectively occludes both passages  62 , and as such, no flow into or out of the cannula would take place. Rotating the collar  38  so that the passages  62  in the conduits  60  are positioned at P 2  aligns one of the passages  62  with an egression lumen  45 , in this case egression lumen  45   d . The second passage  62  is occluded however and not aligned with an ingression lumen. This position enables the operator or medical personnel to suction fluids from the patient  10  without losing suction by having an open pathway through an ingression lumen  44 . Rotating the collar  38  to any of positions P 3 , P 4 , or P 5  aligns the passages  62  in the conduits  60  with; ingression lumen  44   a  and egression lumen  45   a , ingression lumen  44   b  and egression lumen  45   b , and ingression lumen  44   c  and egression lumen  45   c  respectively. Any of these orientations enable the operator to introduce fluids into the patient&#39;s respiratory system and to suction them out during the same operation. For example, the operator may wish to introduce an antimicrobial solution to reduce the potential for infection. In such instances it may be desirable to introduce the fluid and to suction it out in a relatively short period of time. P 6  aligns one of the passages  62  with an ingression lumen  44 , in this case egression lumen  44   d . The second passage  62  is occluded however and not aligned with an egression lumen. This position enables the operator or medical personnel to introduce fluids, such as medication, into the patient  10  without immediately suctioning the medicine out of the patient  10 . It can be seen on the  FIG. 4  illustration that movement of the collar  38  over positions P 1  through P 6  accomplishes a partial revolution about the tube  12  of approximately 180 degrees. 
     The above description provides for a completely occluded position, P 1 , a suction only position, P 2 , and an introduction only position, P 6 , respectively. It should, however, be understood that the devices themselves that perform the suctioning and/or introduction of fluids do not form part of the invention and are thus not depicted. Nevertheless, each of these devices would likely be provided with means to enable or disable them. Additionally, it is not necessary that such devices be connected to either or both of the conduits  60 . As such, fluid flow through any of the lumens may be controlled independently by the devices that are connected to either of the two conduits, irrespective of the intended function of the specific lumen. Through this, the embodiment depicted in  FIG. 3  is capable of a no-flow position, a suction only position, and/or a discharge only position. 
     Yet another alternative embodiment as shown in  FIG. 6  would enable 360 degree rotation of the collar  38  about the tube  12 . In this embodiment, the collar  38  contains a single conduit  60  having separate passages  62   a  and  62   b  therethrough. These passages  62   a  and  62   b  are illustrated as being side-by-side and adjacent to one another, separated by a divider  64 . However other arrangements such as coaxial are contemplated as well. In any event, the passages  62   a  and  62   b  align with lumens  44  and  45  respectively. Unlike in the  FIGS. 3 and 4  embodiments which diametrically oppose the ingression lumens  44  with the egression lumens  45 , this embodiment places them into paired arrangements which repeat about the circumference of the tube  12 . An advantage of this embodiment is that irrigation or introduction of fluids may be made in very close proximity to suctioning should this be desirable or necessary and should the ports  40  and  41  be proximate to one another. 
       FIG. 7  depicts still another embodiment. In this embodiment, the ingression lumens  44  and the egression lumens  45  may be arranged in any suitable configuration, including those shown in  FIGS. 3 ,  4 , and  6 . In this embodiment, however, a second collar  39  is provided. One collar, for example, collar  38  is adapted to align only with the inlets  56  of ingression lumens  44  whereas collar  39  is adapted to align only with the outlets  58  of ingression lumens  45 . Otherwise, the collars  38  and  39  as well as the lumens  44  and  45  operate in the exact same manner as those described above. 
     It should be seen in any of the embodiments described above, that by rotating the collar  38  and/or  39  into a desired position, the user or medical personnel is provided with a selectable means with which to add or suction fluids from the patient  10 . In some embodiments, the passage or passages  62  within the collar  38  may be configured to access more than one lumen  44  or  45  simultaneously. 
     Looking finally to  FIG. 8 , a partial cutaway view normal to the  FIG. 3  view depicts the internal configuration of one embodiment of the collar  38  for additional clarity. This view depicts the tube  12 , the ventilation lumen  42 , one ingression lumen  44   a  separated from the ventilation lumen by the first wall  46  and bounded on the opposite side by the second wall  48 . Likewise the corresponding egression lumen  45   a  is depicted as well. It too is separated from the ventilation lumen by the first wall  46  and bounded on the opposite side by the second wall  48 . As is evident, the inlet  56  may be clearly seen as forming a passage through the second wall  48  into the ingression lumen  44   a  whereas the outlet  58  may be clearly seen as forming a passage through the second wall  48  into the egression lumen  45   a . Details with respect to the guide  54  as well as the collar  38  may be seen. As can be seen, in some embodiments, the guide  54  is secured to the tube  12  such that rotational movement of the guide with respect to the tube is prevented. Appropriate measures should be taken to ensure that the collar  38  is capable of rotation with respect to the guide  54 . For example, a flanged interface  66  between the two components may be used. Such an interface should be fluid tight so as not to enable air leakage into the system when suctioning or to have fluid leakage from the system to the environment. As such, those skilled in the art would understand and be capable of providing an appropriate fluid tight seal to these areas. 
     During use, the collar  38 , and  39  if provided, would be rotated to the desired position. An indicator  68 , for example, such as the one depicted in  FIG. 3  may be provided. An indicator would enable a user to appropriately align the passage  62  within the conduit  60  with the desired lumen. As such, an indicator may be provided which corresponds to each lumen. In lieu or in addition, the collar  38  may be made to incrementally click, lock, or snap into each position. This may be accomplished by any number of means known to those with skill in the art. As can be seen from the FIGs. and from the detailed description each lumen is designed to operate in only one direction. This is to prevent cross contamination of the ingression lumens with the egression lumens as well as to minimize the need to backflush any one lumen thus preventing reintroduction of contaminants that coat any particular egression lumen  45 . Additionally, in some embodiments, a one way valve (not shown) may be included, in the ingression path, the egression path, or both so as to prevent such cross contamination. 
     As used herein and in the claims, the term “comprising” is inclusive or open-ended and does not exclude additional unrecited elements, compositional components, or method steps. 
     While various patents have been incorporated herein by reference, to the extent there is any inconsistency between incorporated material and that of the written specification, the written specification shall control. In addition, while the invention has been described in detail with respect to specific embodiments thereof, it will be apparent to those skilled in the art that various alterations, modifications and other changes may be made to the invention without departing from the spirit and scope of the present invention. It is therefore intended that the claims cover all such modifications, alterations and other changes encompassed by the appended claims.