Abstract:
A closed surgical drain assembly includes a base having an adhesive surface adapted to adhere to a patient&#39;s skin, the base including a reservoir retainer. The assembly further includes a removable reservoir adapted to be received and supported by the reservoir retainer of the base, and a drainage tube that provides fluid communication between the patient and the reservoir.

Description:
[0001]    This application claims priority to U.S. Provisional Application Ser. No. 60/881,881, filed on Jan. 22, 2007, which is incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    Following surgical dissection and/or tissue removal, a cavity known as “dead space” is created that can potentially fill with blood, plasma, and fluids. To prevent a seroma (body cavity fluid accumulation) in the “dead space”, the surgeon or interventionist often leaves a drain. The drain can stay in for days to weeks afterwards depending on the volume and characteristic of the drainage fluid. Typically these drains have a flexible narrow tube that is either perforated or slotted for the portion within the body cavity, which exits the skin where it is sutured. The drain continues from the skin as external tubing into a bulb reservoir collection device that hangs from the wound and is pinned to dressings or clothing. Whereas the intra-cavity component of the closed surgical drains are adequate (“Jackson-Pratt” or “Blake” drain designs), the portion of the drainage system after it exits the skin has several problems. The problems that plague current closed surgical drains are partly due to the long tube that connects to the external (bulb) reservoir. 
         [0003]    Further, patient dissatisfaction is high with current surgical drains because of the inability to wear normal clothing. Patients simply do not know where to put the bulb reservoir. There is also the constant issue of what to do with the long drainage tube. Other problems include skin irritation and pulling at suture sites and leakage at skin insertion/exit sites. 
         [0004]    In addition, the exposed drain tube requires frequent “stripping” to prevent clogging. Also, it is messy to empty the collection device for measuring purposes. 
       SUMMARY OF THE INVENTION 
       [0005]    In a first embodiment of the invention, a closed surgical drain assembly includes a base having an adhesive surface adapted to adhere to a patient&#39;s skin, the base including a reservoir retainer. The assembly further includes a removable reservoir adapted to be received and supported by the reservoir retainer of the base, and a drainage tube that provides fluid communication between the patient and the reservoir. 
         [0006]    The reservoir retainer may comprise a pouch adapted to receive the reservoir. The pouch may be formed of compliant material. 
         [0007]    The drainage tube may include a first drain tube portion adapted to extend proximally into the patient, a second drain tube portion communicating with the reservoir, and a coupling that couples the first drain tube portion with the second drain tube portion. The coupling may be a quick connect/disconnect coupling. 
         [0008]    The first drain tube portion may be adapted to extend through an opening in the patient&#39;s skin and include a sealing flange that makes surface contact with the patient&#39;s skin about the opening. The adhesive surface of the base may be arranged to make adhesive contact with the first drain tube portion flange and with the patient&#39;s skin about the flange to form an adhesive supported seal about the opening. 
         [0009]    The first drain tube portion may have an increasing diameter portion that increases in diameter in the direction of fluid flow towards the reservoir to prevent clogging of the drain. The increasing diameter portion may be immediately proximal of the first drain tube portion flange. 
         [0010]    The reservoir has a distal end and may include a drainage port at its distal end. The reservoir may include fluid level indicia. The base may further include suture tabs adapted to receive suture and assist the adhesive surface in adhering the base to the patient&#39;s skin. 
         [0011]    In another embodiment, a closed surgical drain assembly comprises a base adapted to be worn on a patient&#39;s skin, a reservoir supported by the base, and a drainage tube that provides fluid communication between the patient and the reservoir. The drainage tube includes an increasing diameter portion that increases in diameter in the direction of fluid flow, and is arranged to be beneath and immediately adjacent to the patient&#39;s skin. 
         [0012]    The base may include a retainer for holding the reservoir. The retainer may comprise a pouch formed of compliant material. 
         [0013]    The base may include an adhesive surface that adheres to the patient&#39;s skin. The drainage tube may include a first drain tube portion, including the increasing diameter portion, adapted to extend proximally into the patient, a second drain tube portion communicating with the reservoir, and a coupling that couples the first drain tube portion with the second drain tube portion. The coupling may be a quick connect/disconnect coupling. 
         [0014]    The first drain tube portion may be adapted to extend through an opening in the patient&#39;s skin and may include a sealing flange that makes surface contact with the patient&#39;s skin about the opening. The base may have an adhesive surface arranged to make adhesive contact with the first drain tube portion flange and with the patient&#39;s skin about the flange to form an adhesive supported seal about the opening. 
         [0015]    The features of the present invention which are believed to be novel are set forth with particularity in the appended claims. The invention, together with further features and advantages thereof, may best be understood by making reference to the following description taken in conjunction with the accompanying drawings, in the several figures of which like reference numerals identify identical elements, and wherein: 
     
    
     
       DESCRIPTION OF THE DRAWINGS 
         [0016]      FIG. 1  is a perspective view of a surgical drain assembly according to an embodiment of the invention; 
           [0017]      FIG. 2  is a perspective representation of the drain and base unit of the surgical drain assembly of  FIG. 1 ; 
           [0018]      FIG. 3  is a top view of the surgical drain assembly of  FIG. 1 ; 
           [0019]      FIG. 4  is a top view of the surgical drain assembly of  FIG. 1  showing the replaceable reservoir bag removed; 
           [0020]      FIG. 5  is a front plan view of a closed surgical drain assembly according to another embodiment of the invention; 
           [0021]      FIG. 6  is a rear plan view of the closed surgical drain assembly of  FIG. 5 ; and 
           [0022]      FIG. 7  is a partial side view showing details of the sealing of the drainage site with the closed surgical drain assembly of  FIG. 5 . 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0023]    To circumvent the above noted problems, the present invention, in its various embodiments, provides improved closed surgical drain assemblies. The assembly  10  of  FIGS. 1-4  is one such embodiment of the present invention. The closed surgical drain assembly there shown includes flexible anatomic base unit  12  that has a flat moldable, adherent surface  14  for skin adherence. The base  12  may thus be worn over or near the drainage tube insertion site. Reinforcement suture tabs  28  may be included for particularly difficult body sites. The anatomic base unit  12  is integrated with a tapered drain  16  exiting on the patient&#39;s skin to completely eliminate any external drainage tubing. On the outer-facing side, the anatomic base unit has receptacles  22  for attachment of a disposable snap-on collection reservoir bag  20 . 
         [0024]    The internal drain  16  is a tapered tube that widens in diameter as the drain leaves the body cavity and enters the reservoir base unit. This eliminates the need to periodically strip the drain and prevents clogging. 
         [0025]    The disposable collection reservoir bag  20  may be removed from the anatomic base unit  12  when full, leaving the anatomic base unit  12  with drain  16  intact on the skin. A new disposable reservoir bag may then be easily snapped onto the moldable anatomic base unit. The disposable collection reservoir bag  20  is sealed but upon connection to base unit  12 , auto-expands to apply negative pressure to the drain. 
         [0026]    The sealed collection reservoir bag  20  may contain markers  24  indicating the amount of fluid within the reservoir, making measurement of the drainage amount easy and without mess. The patient or care providers do not have to manipulate the fluid and there is no risk of spilling or contact with the drainage fluid. 
         [0027]    Alternatively or in addition, the reservoir bag  20  may contain a nipple valve  26  that self-seals to allow hook-up of a tubing-syringe combo to drain and measure amount or, a recharge packet that hooks into the nipple valve that can collapse the primary reservoir and drain the contents automatically. In some embodiments, large base units with attachable reservoirs could accommodate more than one drain for larger wounds that are difficult surgical management problems such as with open abdomens or complicated degloving injuries. 
         [0028]    In one embodiment, the flexible anatomic unit and drain are integrated, but the reservoir is disposable and allows rapid re-attachment to the base anatomic unit. In another embodiment, the base anatomic unit, collection reservoir and drain are integrated as a single device. The catheter/drain portion that is within the body cavity can be of any configuration, with or without trocar. 
         [0029]    Referring now to  FIGS. 5-7 , they show another closed surgical drain assembly  50  according to a further embodiment of the invention. The assembly  50  generally comprises a base  60 , a reservoir  70 , and a drain tube assembly  80 . 
         [0030]    The base  60  is formed of flexible material to conform to the body contour of the patient. The base includes an adhesive coated rear surface  62  for adhering the base to the patient&#39;s skin. The adhesive surface  62  may initially be covered with a strippable cover that may be removed prior to deployment of the assembly  50 . 
         [0031]    The base  60  further includes a reservoir retainer to support and hold the reservoir  70 . Here, the reservoir retainer  64  is a pouch  66 . The pouch is preferably formed of a flexible compliant material as, for example, a flexible mesh material. The pouch includes a large opening  68  through which the reservoir  70  may be placed. The reservoir is preferably formed of a conformal elastic material so that it may be initially in a bundled configuration when placed into the pouch and then released to impose a negative pressure on the system as previously described. 
         [0032]    While the retainer  64  in this embodiment comprises a pouch, other forms of retainers may be employed as well without departing from the present invention. Such other forms of retainers may comprise, for example and without limitation, straps, bands, Velcro, snaps, or tabs. 
         [0033]    The reservoir includes a drain  72  at its distal end that projects through an opening  67  within the pouch  66 . The drain permits the reservoir to be drained should it become full without a replacement being immediately available. 
         [0034]    The drain assembly  80  includes a first drain tube  82  and a second drain tube  84 . The second drain  84  tube is attached to the reservoir. The first drain tube  82  extends from within the patient at a drainage site. A coupling  86  couples the first and second drain tubes  82  and  84  together. The coupling may be, for example, a quick connect/disconnect coupling well know in the art. This enables a filled reservoir to be readily replaced with a new one without disturbing the drainage site. 
         [0035]    As may best be seen in  FIGS. 6 and 7 , the first drain tube  82  includes a tapered section  88  that causes the tube  82  to increase in diameter in the direction of fluid flow from the patient to the reservoir  70 . The tapered portion  88  terminates immediately adjacent and proximal to a sealing flange  89 . The tapered portion  88  prevents the drain assembly  80  from clogging and eliminates the need to periodically strip the drain for cleaning. 
         [0036]    The sealing flange  89  together with the adhesive surface  62  of the base  60  provides a sealed closed drainage system. As may be best seen in  FIG. 7 , the sealing flange  89  makes broad surface contact with the patient&#39;s skin about the opening  92  in the patient&#39;s skin  90  through which the first drain tube passes. The adhesive surface  62  of the base  60  makes broad covering surface contact with the sealing flange  89 . Hence, the adhesive surface  62  of the base  60  is arranged to make adhesive contact with the first drain tube flange  89  and with the patient&#39;s skin  90  about the flange to form an adhesive supported seal about the opening  92 . 
         [0037]    From the foregoing, it may be seen that the present invention overcomes many of the problems experienced with prior art closed surgical drain systems. The drain assembly of the present invention may be worn by a patient in comfort and permits the patient to wear normal clothing. The sealing arrangement for the drainage sight minimizes leaks and completely seals the drainage sight. Still further, no long drain tube is required and drain tube stripping is eliminated by the anti-clogging configuration of the drain assembly. Still further, the reservoir and base may be made in any shape to conform with virtually every localized area of a patient&#39;s body. The reservoirs may be made in pre-fashioned shapes and sizes to this end. 
         [0038]    While particular embodiments of the present invention have been shown and described, modifications may be made, and it is therefore intended in the appended claims to cover all such changes and modifications which fall within the true spirit and scope of the invention as defined by those claims.