Abstract:
A sampling port having a mechanical valve for a drainage apparatus is disclosed which permits a practitioner to directly access a collection chamber of the drainage apparatus using a needle-less syringe for withdrawing a sample of fluid therefrom. The sampling port comprises a port in direct communication with the collection chamber and a mechanical valve partially disposed inside the port. The mechanical valve comprises a generally tubular body containing a spring loaded valve that is normally closed to fluid flow communication and operable using a needle-less tip syringe to actuate the valve. In operation, a practitioner engages the needle-less tip syringe to the valve which places the valve in an open position and permits fluid flow into the syringe as the practitioner draws back on the plunger of the syringe.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a chest drainage system, and particularly to a chest drainage device for suctioning gases and liquids from the chest cavity of a patient. More specifically, the present invention relates to a sampling port for directly accessing a collection chamber of the chest drainage device. 
     2. Prior Art 
     A chest drainage device is an apparatus for suctioning gases and liquids from the pleural cavity of patients. The pleural cavity lies within the rib cage above the diaphragm and is surrounded by the pleural membrane. The pleural cavity contains both lungs, which in their normal expanded state fill the pleural cavity. Several conditions and diseases such as interventional surgery, trauma, emphysema and various respiratory infections can cause build up of liquid and gases around the lungs in the intrapleural space. When this happens, it causes the lungs to collapse to a volume much less than that of the pleural cavity, thereby severely impairing the breathing functions of the patient. The lungs can be re-expanded to their normal state to fill the pleural cavity by draining the liquid and gases from the pleural cavity using a chest drainage device. 
     There are many kinds of chest drainage devices used to drain the pleural cavity of a patient. One kind of drainage device, sometimes referred to as a “three-bottle” type, is illustrated in U.S. Pat. No. 3,363,626 to Bidwell et al. entitled “Underwater Drainage Apparatus”. The “three-bottle” type drainage device has three interconnecting chambers which comprise: (1) a collection chamber for collecting liquids and gases suctioned from the patient&#39;s pleural cavity through a catheter; (2) an underwater seal chamber which communicates with the collection chamber and has a water seal which acts as a one way valve for passing gases collected from the patient&#39;s pleural cavity to the atmosphere; and (3) a suction control chamber for limiting the maximum suction (or negative pressure) applied to the patient&#39;s pleural cavity. 
     In operation, a source of vacuum is applied to the Bidwell et al. device such that the negative pressure generated in the collection chamber causes shed liquid and gases from the patient&#39;s pleural cavity to collect inside the collection chamber. As the liquid and gases enter the collection chamber, the vacuum establishes a fluid pathway which causes the collected gases to pass from the collection chamber and through the water seal of the water seal chamber. Once through the water seal, the gases are evacuated from the drainage device through a vacuum port which is in communication with the water seal chamber. 
     Often it is desirable to draw a sample of collected fluid directly from the collection chamber of a chest drainage device in order to perform periodic testing of the fluid. The chest drainage devices of the prior art use non-mechanical valves which require a needle tipped syringe in order to directly access fluid in the collection chamber. These non-mechanical valves are usually grommet or rubber bung ports located adjacent the collection chamber which have an elastomeric membrane that reseals when penetrated by a needle tipped syringe. However, the drawback with using a needle tipped syringe with such prior art sampling ports is the potential danger of a user being inadvertently stuck with a contaminated needle after withdrawing a sample of fluid from the collection chamber. 
     Therefore, there is a need in the art for a sampling port which permits direct withdraw of a fluid sample from the collection chamber of a drainage device using a needle-less syringe. There is a further need in the art for a drainage device having a mechanical sampling port that permits easy and direct access to the collection chamber. 
     OBJECTS AND SUMMARY OF THE INVENTION 
     The primary object of the present invention is to provide a mechanical sampling port for a drainage device. 
     Another object of the present invention is to provide a mechanical sampling port which directly communicates with the collection chamber of a medical drainage device using a needle-less syringe. 
     In brief summary, the present invention overcomes and substantially alleviates the deficiencies present in the art by providing a mechanical sampling port for a drainage device which allows direct access to the collection chamber using a needle-less syringe. 
     Preferably, the drainage device comprises a mechanical sampling port and related method of use thereof for a chest drainage device that permits the practitioner to withdraw a sample of fluid directly from the collection chamber using a needle-less syringe. The sampling port comprises a mechanical two way valve which directly communicates and accesses the collection chamber. The practitioner utilizes the sampling port by engaging a needle-less syringe, for example a luer tip syringe, into the two way valve inside the sampling port which places the two-way valve in the open position. When the practitioner desires to withdraw a sample of fluid, he or she simply pulls back the plunger of the syringe until a sufficient amount of blood or fluid from the collection chamber fills the syringe. Once a sufficient amount of fluid is withdrawn from the collection chamber, the user disengages the syringe which automatically returns the two-way valve to the normally closed position. 
     In an alternate embodiment, the sampling port uses a one-way valve instead of a two-way valve to access the collection chamber. The one-way valve comprises a body having a first interior chamber in communication with a second interior chamber separated by an inner shoulder. Similar to the preferred embodiment, an insert is engaged to one end of the body. However, unlike the preferred embodiment, the alternate embodiment includes a spring-loaded valve member which selectively engages a seat formed by the insert when the one-way valve is operated between open and closed positions. In operation, the practitioner engages a needle-less syringe to one end of the one-way valve and actuates the plunger of the syringe to create a suction inside first and second interior chambers. The suction causes the spring-loaded valve member to disengage from the seat and permit fluid flow communication with the collection chamber so that a sample may be withdrawn. 
     These and other objects of the present invention are realized in the preferred embodiment, described by way of example and not by way of limitation, which provides for a mechanical sampling port for a drainage device that permits the practitioner to use a needle-less syringe to directly access the collection chamber. 
     Additional objects, advantages and novel features of the invention will be set forth in the description which follows, and will become apparent to those skilled in the art upon examination of the following more detailed description and drawings in which like elements of the invention are similarly numbered throughout. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a front view of the drainage device according to the present invention; 
     FIG. 2 is a rear view of the drainage device showing the sampling port according to the present invention; 
     FIG. 3 is a front view of the drainage device illustrating its basic operative features, functions and air flow pathways; 
     FIG. 4 is a cross-sectional view along line A—A of FIG. 3 according to the present invention. 
     FIG. 5 is a perspective view of the two way valve of the sampling port according to the present invention; 
     FIG. 6 is a cross-sectional view of the two way valve taken along line B—B of FIG. 5 according to the present invention; 
     FIG. 7 a  is a partial cross-sectional view illustrating the method of engaging a needle-less syringe to the sampling port prior to engagement with the two way valve according to the present invention; 
     FIG. 7 b  is a partial cross-sectional view illustrating the method of engaging a needle-less syringe to the sampling port showing the needle-less syringe engaged with the two way valve according to the present invention; 
     FIG. 8 is a partial cross-sectional view of the two way valve disposed inside the sampling port according to the present invention; 
     FIG. 9 a  is a cross-sectional view of an alternate embodiment of a one-way valve shown in a closed position according to the present invention; and 
     FIG. 9 b  is a cross-sectional view of the alternate embodiment of the one-way valve shown in the open position according to the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring to the drawings, the preferred embodiment of the drainage device used with the sampling port  18  of the present invention is illustrated and generally indicated as  10  in FIG.  1 . Drainage device  10  comprises a casing  12  defined by a front wall  84 , rear wall  86  (FIG.  2 ), top wall  92 , bottom wall  94 , and opposing side walls  88  and  90 . Casing  12  is further defined by a collection chamber  14  for the collection of shed fluids from a patient&#39;s pleural cavity, a water seal chamber  16  in communication with the collection chamber  14  for preventing reflux of evacuated gases back to the patient, and a suction control chamber  17  (FIG. 4) in communication with the water seal chamber  16  for regulating the degree of vacuum inside drainage device  10 . As further shown, casing  12  comprises interior partitions  116 ,  118 ,  120 ,  122  and  124  which are parallel to front and rear walls  84  and  86 , and a partition  125  (FIG.  4 ), which is parallel to front and rear walls  84  and  86 , that divide the interior of casing  12  into collection chamber  14 , water seal chamber  16  suction control chamber  17  as well as a number of other various chambers and compartments. 
     Referring to FIG. 3, drainage device  10  comprises a negative pressure relief valve  28  for venting excess negative pressure from within casing  12 , a collection port  26  for attachment to patient tubing  32  (FIG.  1 ), a vacuum regulator assembly  24  for the mechanical regulation of vacuum inside drainage device  10 , and a vacuum indicator assembly  25  for giving a visual indication to the user of proper vacuum being applied to collection chamber  14 . In the alternative, the present invention contemplates that the sampling port  18  may be used with other kinds of drainage devices  10 , for example a drainage device  10  having a water column to regulate the level of vacuum rather than a vacuum regulator assembly  24 . A handle  96  is also provided along top wall  92  for handling and transporting drainage device  10 , while a rotatable stand  98  is attached to bottom wall  94  for providing a stable platform for drainage device  10 . 
     As further shown, partitions  116  and  118  divide collection chamber  14  into compartments  14   a ,  14   b  and  14   c , to facilitate periodic monitoring of the level of liquid  34  collected from the patient&#39;s chest cavity. As shown by arrow  100 , vacuum applied to drainage device  10  forces blood and other liquid  34  from the patient&#39;s chest cavity into compartment  14   a  through collection port  26  via patient tubing  32 . When compartment  14   a  is filled to capacity, arrow  102  illustrates that any additional liquid  34  will overflow through a port  106  and into compartment  14   b  until that compartment is completely filled. Once compartment  14   b  is filled to capacity, arrow  104  shows that any additional liquid  34  will overflow through a port  108  and drop into compartment  14   c . The present invention contemplates the use of appropriate indicia (not shown) marked along front wall  84  (FIG. 1) for each compartment  14   a ,  14   b  and  14   c , respectively, for providing a clear visual indication of the level of liquid  34  in each respective compartment. 
     Referring to FIGS. 3 and 4, once fluid from the patient&#39;s cavity is deposited inside collection chamber  14 , gases are evacuated through the water seal chamber  16  as illustrated by arrow  105 . Water seal chamber  16  prevents reflux of gases back to the patient by preventing reentry of such gases into the collection chamber  14  using a buoyant valve  110  in combination with a water seal  21 . The structure and operation of the buoyant valve  110  is disclosed in U.S. Pat. No. 5,931,821 to Weilbacher et al., entitled “Chest Drainage Unit With Controlled Automatic Excess Negativity Relief Feature” which is incorporated by reference in its entirety. The water seal chamber  16  comprises a compartment  126  having upper and lower portions with the upper portion housing valve  110  and the lower portion having water seal  21  disposed therein. The lower portion of compartment  126  communicates with the lower portion of the suction control chamber  17  which is separated from compartment  126  by partition  125 . As gases pass through the water seal  21  from collection chamber  14 , the gases are evacuated from drainage device  10  through vacuum regulator assembly  24  to a vacuum source (not shown). 
     As further shown, vacuum regulator assembly  24  provides a means for regulating the degree of vacuum, venting of excess positive pressure, and a pathway for evacuating gases from drainage device  10 . The basic operation of vacuum regulator assembly  24  is disclosed in U.S. Pat. No. 4,911,697 to Kerwin and is herein incorporated by reference in its entirety. Preferably, vacuum regulator assembly  24  comprises a positive pressure relief valve (not shown) for venting excess positive pressure generated inside collection port  14  and a vacuum port  128  for communicating with a source of vacuum. Both the positive pressure relief valve and vacuum port  128  communicate with suction control chamber  17  which is in fluid flow communication with water seal  21 . Once the gas passes through water seal  21  it is evacuated from the suction control chamber  17  through the vacuum port  128  to the vacuum source. 
     Referring to FIGS. 1-3 and  8 , sampling port  18  of the present invention shall now be discussed. Sampling port  18  is located along rear wall  86  of drainage device  10  such that port  18  communicates directly with collection chamber  14  along compartment  14   a , although the present invention contemplates that port  18  may be located along any wall which communicates directly with collection chamber  14  for withdrawing a sample. As further shown, sampling port  18  comprises an aperture  36  formed through rear wall  86  having a two-way valve  22  disposed therein. Referring to FIG. 5, two-way valve  22  has a generally tubular shaped body  46  having a distal end  52  and proximal end  54  with an annular flange  48  formed around a middle portion  49  of body  46 . Flange  48  serves to securely engage and retain two-way valve  22  within aperture  36 , as shall be explained in greater detail below. Referring to FIGS. 5 and 6, two-way valve  22  further comprises an insert  50  extending axially from body  46  having an opening  60  which is securely coupled to the distal end  52  of two-way valve  22 . The proximal end  54  of two-way valve  22  forms a proximal opening  58  which selectively communicates with distal opening  60  through a main chamber  47  when two-way valve  22  is placed in the open position. As illustrated in FIG. 8, rear wall  86  includes a retention portion  38  which extends inwardly from wall  86  and is sized and shaped to securely engage flange  48  such that the distal end  52  of two-way valve  22  is oriented to communicate directly with the collection chamber  14 . 
     Referring specifically to FIG. 6, the basic operation of two-way valve  22  shall be discussed in greater detail. Two-way valve  22  is a spring loaded valve that is normally closed to fluid flow communication. As further shown, proximal opening  58  opens into a first interior chamber  62  formed within main chamber  47  where an activation member  66  is disposed therein and attached to a push rod  64 . Push rod  64  has an elongated body  65  which includes a proximal portion  72  that is disposed in first interior chamber  62 , a middle portion  70  that has an annular flange  76  for selectively sealing off fluid flow through body  46 , and a distal portion  68  which is disposed within a second interior chamber  63 . First interior chamber  62  and the second interior chamber  63  are separated by an inner shoulder  74  which defines an aperture  78  adapted to receive push rod  64  slidably therethrough. To maintain a fluid tight seal when two-way valve  22  is in the closed position, an annular seal  82  is provided which is coupled around push rod  64  adjacent flange  76  and is adapted to seal off aperture  78  from fluid flow communication between first interior chamber  62  and second interior chamber  63  when two-way valve  22  is placed in the normally closed position. 
     To bias two-way valve  22  in the normally closed position, a spring  80  is provided which has one end attached to the middle portion  70  of push rod  64  and the other end attached to insert  50  by means well known in the art. The spring  80  creates a continual forward bias towards the proximal end  54  such that seal  82  is forced to abut inner shoulder  74  and close off fluid flow communication between first and second interior chambers  62  and  63 , unless push rod  64  is properly activated. 
     In operation, two-way valve  22  is activated by the practitioner inserting a conventional needle-less syringe  40 , preferably having a luer tip  42 , through the proximal opening  58  until luer tip  42  engages activation member  66 , as shown in the sequence illustrated in FIGS. 7 a  and  7   b . As the practitioner pushes the syringe  40  through first interior chamber  62  and contacts activation member  66 , the push rod  64  is caused to move axially towards distal end  52  which overcomes the spring force applied by spring  80  and unseats seal  82  from aperture  78 , thereby establishing fluid flow communication between first and second interior chambers  62  and  63 . The practitioner may then draw back the plunger  44  of syringe  40  so that a sample of liquid  34  may be taken directly from the collection chamber  14  and drawn into syringe  40 . Once a predetermined amount of liquid  34  is withdrawn directly from collection chamber  14 , the practitioner disengages the luer tip  42  from activation member  66  which causes the spring force applied by spring  80  to force seal  82  against aperture  78  and return two-way valve  22  to the normally closed position. 
     Referring to FIGS. 9 a  and  9   b , an alternate embodiment of two way valve  22  will now be discussed. The present invention contemplates utilizing a one-way valve  122  rather than the two-way valve  22  of the preferred embodiment. One-way valve  122  is similar to the two-way valve  22  in that one-way valve  122  is a spring-loaded valve that is normally closed to fluid flow communication. As shown, one-way valve  122  comprises a tubular shaped body  146  having a distal end  152  and a proximal end  154  with an annular flange  148  formed around a middle portion  149 . An insert  150  is securely engaged with the distal end  152  of tubular body  146 . The proximal end  154  forms a proximal opening  158  which selectively communicates with a distal opening  152  through first and second interior chambers  162  and  163 , while distal end  160  communicates with a third interior chamber  165 . One-way valve  122  further includes a spring-loaded valve member  170  operatively connected to a spring  180 . As further shown, spring  180  provides a spring force which maintains valve member  170  in a normally closed position against a seat  172  which prevents fluid flow communication between second interior chamber  163  and third interior chamber  165 . One end of spring  180  is attached to an inner shoulder  174  and the other end to valve member  170  by means well known in the art. In operation, a practitioner engages the end of a luer-tip syringe (not shown) to the proximal end  154  of one-way valve  122  and pulls back on the plunger. As the plunger is pulled back, suction is created within the first and second interior chambers  162  and  163  that overcomes the applied spring force and automatically causes the valve member  170  to disengage from seat  172  to permit fluid flow through third interior chamber  165 . Once a predetermined amount of fluid has been withdrawn from the collection chamber  14 , the practitioner disengages the syringe from the one-way valve  122  which terminates the applied suction and causes valve member  170  to engage seat  172 . 
     Although the present invention contemplates that syringe  40  have a luer tip  42 , other suitable needle-less means of engaging two-way valve  22  may be utilized which are adapted to mechanically activate valve  22  in the manner described above. 
     Preferably, sampling port  18  is located along a mid-point between top and bottom walls  92  and  94  as illustrated in FIG. 1; however, sampling port  18  may also be located along any suitable point along casing  12  as long as port  18  communicates directly with collection chamber  14 . 
     Preferably, two-way valve  22  is a BESPAK valve manufactured by Bespak of Cary, N.C., although any mechanical two way valve which is actuatable using a needle-less syringe is felt to fall with the spirit and scope of the present invention. 
     It should be understood from the foregoing that, while particular embodiments of the invention have been illustrated and described, various modifications can be made thereto without departing from the spirit and scope of the present invention. Therefore, it is not intended that the invention be limited by the specification; instead, the scope of the present invention is intended to be limited only by the appended claims.