Patent Publication Number: US-2021178132-A1

Title: System and apparatus for treating a tissue site having an in-line canister

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of U.S. patent application Ser. No. 15/972,400, filed May 7, 2018, which is a continuation of U.S. patent application Ser. No. 13/653,997, filed Oct. 17, 2012, now U.S. Pat. No. 10,004,880, which claims priority to U.S. Provisional Patent Application No. 61/548,129, filed Oct. 17, 2011, entitled “SYSTEM AND APPARATUS FOR TREATING A TISSUE SITE HAVING AN IN-LINE CANISTER,” all of which are hereby incorporated by reference in their entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates generally to reduced pressure treatment systems and more particularly to a system and apparatus for treating a tissue site having an in-line canister. 
     2. Description of Related Art 
     Clinical studies and practice have shown that providing a reduced pressure in proximity to a tissue site augments and accelerates the growth of new tissue at the tissue site. The applications of this phenomenon are numerous, but one particular application of reduced pressure involves treating wounds. This treatment (frequently referred to in the medical community as “negative pressure wound therapy,” “reduced pressure therapy,” or “vacuum therapy”) provides a number of benefits, including migration of epithelial and subcutaneous tissues, improved blood flow, and micro-deformation of tissue at the wound site. Together these benefits result in increased development of granulation tissue and faster healing times. Typically, reduced pressure is applied by a reduced pressure source to tissue through a porous pad or other manifold device. The porous pad contains cells or pores that are capable of distributing reduced pressure to the tissue and channeling fluids that are drawn from the tissue. The porous pad often is incorporated into a dressing having other components that facilitate treatment. 
     SUMMARY 
     The problems presented by existing reduced pressure treatment systems are solved by the systems and methods of the illustrative embodiments described herein. In one illustrative embodiment, a canister for use in administering reduced pressure to a tissue site includes a center body, a first end cap, and a second end cap. The center body has a first end, a second end, and a number of fluidly separate body conduits extending from the first end to the second end. The first end cap is connected to the first end of the center body and has a number of return conduits configured to fluidly connect one of the body conduits with another of the body conduits. The first end cap further has a port for receiving a conduit in fluid communication with the tissue site. The second end cap is connected to the second end of the center body and has a number of return conduits configured to fluidly connect one of the body conduits with another of the body conduits. The second end cap further has a port for receiving a conduit in fluid communication with a reduced pressure source. The fluid connection between the body conduits and the return conduits of the first and second end caps creates a continuous, tortuous pathway. 
     In another illustrative embodiment, a canister for use in administering reduced pressure to a tissue site includes a center body, a first end cap and a second end cap. The center body has a first end, a second end, and a number of fluidly separate body conduits extending from the first end to the second end. An absorbent material is positioned in each of the number of fluidly separate body conduits. The first end cap is connected to the first end of the center body, and the first end cap has an inlet port, an outlet port, and a first plenum for receiving fluids. The second end cap is connected to the second end of the center body and has a second plenum for receiving fluids. 
     In yet another illustrative embodiment, a system for use in administering reduced pressure to a tissue site includes a reduced-pressure dressing, an in-line canister, and a reduced-pressure treatment unit. The reduced-pressure dressing is positioned proximate the tissue site and includes a manifold positioned within the tissue site for delivering reduced pressure to the tissue site. The in-line canister is fluidly connected to the reduced-pressure dressing through a first conduit and is operable to receive and store fluid received from the tissue site. The in-line canister includes a center body, a first end cap, and a second end cap. The center body has a first end, a second end, and a number of fluidly separate body conduits extending from the first end to the second end. The first end cap is connected to the first end of the center body and has a number of return conduits configured to fluidly connect one of the body conduits with another of the body conduits. The first end cap further has a port for receiving a conduit in fluid communication with the tissue site. The second end cap is connected to the second end of the center body and has a number of return conduits configured to fluidly connect one of the body conduits with another of the body conduits. The second end cap further has a port for receiving a conduit in fluid communication with a reduced pressure source. The fluid connection between the body conduits and the return conduits of the first and second end caps creates a continuous, tortuous pathway. The reduced-pressure treatment unit is fluidly connected to the canister through a second conduit and includes a reduced pressure source for providing reduced pressure to the tissue site. 
     Other objects, features, and advantages of the illustrative embodiments will become apparent with reference to the drawings and detailed description that follow. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates a perspective view, with a portion shown in cross section, of an illustrative embodiment of a system for treating a tissue with reduced pressure; 
         FIG. 2  illustrates a side view of an illustrative embodiment of a canister for use in the system shown in  FIG. 1 ; 
         FIG. 3  illustrates a front view of a first end cap of the canister shown in  FIG. 2  taken along line  3 - 3 ; 
         FIG. 4  illustrates a back view of a second end cap of the canister shown in  FIG. 2  taken along line  4 - 4 ; 
         FIG. 5  illustrates a cross-sectional view of the center body of the canister shown in  FIG. 2  taken along line  5 - 5 ; 
         FIG. 6  illustrates a cross-sectional side view of the canister of  FIG. 2 ; 
         FIG. 7  illustrates a side view of another illustrative embodiment of a canister for use in the system shown in  FIG. 1 ; 
         FIG. 8  illustrates an exploded side view of the canister shown in  FIG. 7 ; 
         FIG. 9  illustrates a front view of a first end cap of the canister shown in  FIG. 7  taken along line  9 - 9 ; 
         FIG. 10  illustrates a back view of a second end cap of the canister shown in  FIG. 7  taken along line  10 - 10 ; 
         FIG. 11  illustrates a cross-sectional side view of the canister shown in  FIG. 7 ; 
         FIGS. 12A and 12B  illustrate a perspective view of another illustrative embodiment of a canister for use in the system shown in  FIG. 1 ; and 
         FIGS. 13A and 13B  illustrate a perspective view of another illustrative embodiment of a canister for use in the system shown in  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     In the following detailed description of several illustrative embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration specific preferred embodiments in which the invention may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the invention, and it is understood that other embodiments may be utilized and that logical structural, mechanical, electrical, and chemical changes may be made without departing from the spirit or scope of the invention. To avoid detail not necessary to enable those skilled in the art to practice the embodiments described herein, the description may omit certain information known to those skilled in the art. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the illustrative embodiments are defined only by the appended claims. Unless otherwise indicated, as used herein, “or” does not require mutual exclusivity. 
     The term “reduced pressure” as used herein generally refers to a pressure less than the ambient pressure at a tissue site that is being subjected to treatment. In most cases, this reduced pressure will be less than the atmospheric pressure at which the patient is located. Alternatively, the reduced pressure may be less than a hydrostatic pressure associated with tissue at the tissue site. Although the terms “vacuum” and “negative pressure” may be used to describe the pressure applied to the tissue site, the actual pressure reduction applied to the tissue site may be significantly less than the pressure reduction normally associated with a complete vacuum. Reduced pressure may initially generate fluid flow in the area of the tissue site. As the hydrostatic pressure around the tissue site approaches the desired reduced pressure, the flow may subside, and the reduced pressure is then maintained. Unless otherwise indicated, values of pressure stated herein are gauge pressures. Similarly, references to increases in reduced pressure typically refer to a decrease in absolute pressure, while decreases in reduced pressure typically refer to an increase in absolute pressure. 
     Referring to  FIG. 1 , an illustrative embodiment of a system  100  for treating a tissue site  102  on a patient  104  with reduced pressure is presented. The system  100  includes a reduced-pressure dressing  106  for disposing proximate the tissue site  102  and a reduced-pressure treatment unit  108  fluidly connected to the reduced-pressure dressing  106  for applying reduced pressure to the tissue site  102 . The system  100  further includes a canister  110  fluidly connected to both the reduced-pressure dressing  106  and the reduced-pressure treatment unit  108 . A first conduit  112  connects the reduced-pressure dressing  106  to the canister  110 , and a second conduit  114  connects the reduced-pressure treatment unit  108  to the canister  110 . The canister  110  is operable to receive and store fluids, including exudate, received from the tissue site  102 . The canister  110  is configured to create a tortuous flow path for any fluids received from the tissue site  102 . There are several potential advantages to having an in-line canister positioned between a tube set and configured to create a tortuous flow path. For example, the configuration may allow for a smaller and more discrete vacuum device and more efficient absorption of the wound exudates. The volumetric size of the canister may be increased with virtually no impact to the size of the vacuum device. 
     The system  100  may be used with various types of tissue sites  102 . As used herein, the term “tissue site” may refer to a wound, such as a wound  116 , or defect located on or within any tissue, including but not limited to, bone tissue, adipose tissue, muscle tissue, neural tissue, dermal tissue, vascular tissue, connective tissue, cartilage, tendons, or ligaments. The term “tissue site” may further refer to areas of any tissue that are not necessarily wounded or defective, but are instead areas in which it is desired to add or promote the growth of additional tissue. For example, reduced pressure tissue treatment may be used in certain tissue areas to grow additional tissue that may be harvested and transplanted to another tissue location. The wound  116  may be through an epidermis  118  and into a subcutaneous tissue or any other tissue. Treatment of the tissue site  102  may include removal of fluids, e.g. exudate or ascites. 
     The reduced-pressure dressing  106  may include a manifold  120  positioned proximate the tissue site  102 . The manifold  120  typically includes a plurality of flow channels or pathways that distribute fluids provided to and removed from the tissue site  102  around the manifold  120 . In one illustrative embodiment, the flow channels or pathways are interconnected to improve distribution of fluids provided or removed from the tissue site  102 . The manifold  120  may be a biocompatible material that is capable of being placed in contact with the tissue site  102  and distributing reduced pressure to the tissue site  102 . Examples of the manifold  120  may include, without limitation, devices that have structural elements arranged to form flow channels, such as, for example, cellular foam, open-cell foam, porous tissue collections, liquids, gels, and foams that include, or cure to include, flow channels. The manifold  120  may be porous and may be made from foam, gauze, felted mat, or any other material suited to a particular biological application. In one embodiment, the manifold  120  is a porous foam and includes a plurality of interconnected cells or pores that act as flow channels. The porous foam may be a polyurethane, open-cell, reticulated foam such as GranuFoam® material manufactured by Kinetic Concepts, Incorporated of San Antonio, Tex. In some situations, the manifold  120  may also be used to distribute fluids such as medications, antibacterials, growth factors, and various solutions to the tissue site  102 . Other layers may be included in or on the manifold  120 , such as absorptive materials, wicking materials, hydrophobic materials, and hydrophilic materials. 
     In one illustrative embodiment, the manifold  120  may be constructed from bioresorbable materials that do not have to be removed from a patient&#39;s body following use of the system  100 . Suitable bioresorbable materials may include, without limitation, a polymeric blend of polylactic acid (PLA) and polyglycolic acid (PGA). The polymeric blend may also include without limitation polycarbonates, polyfumarates, and capralactones. The manifold  120  may further serve as a scaffold for new cell-growth, or a scaffold material may be used in conjunction with the manifold  120  to promote cell-growth. A scaffold is a substance or structure used to enhance or promote the growth of cells or formation of tissue, such as a three-dimensional porous structure that provides a template for cell growth. Illustrative examples of scaffold materials include calcium phosphate, collagen, PLA/PGA, coral hydroxy apatites, carbonates, or processed allograft materials. 
     The reduced-pressure dressing  106  may further include a cover or drape  122  positioned over the manifold  120  to secure the manifold  120  at the tissue site  102  and to create a sealed space  124  over the tissue site  102 . The drape  122  has a first side  126 , and a second, tissue-facing side  128 . The drape  122  may be any material that provides a fluid seal adequate to maintain reduced pressure at a desired site given the particular reduced-pressure source or subsystem involved. The drape  122  may, for example, be an impermeable or semi-permeable, elastomeric material. 
     An attachment device  130  may be used to hold the drape  122  against a portion of the patient&#39;s intact epidermis  118  or another layer, such as a gasket or additional sealing member. The attachment device  130  may take numerous forms. For example, the attachment device  130  may be a medically acceptable adhesive or bonding agent, such as a pressure-sensitive adhesive, that extends about a periphery or all of the drape  122 . The attachment device  130  may also be a sealing ring or other device. The attachment device  130  is disposed on the second, tissue-facing side  128  of the drape  122 . Before use, the attachment device  130  may be covered by a release liner (not shown). 
     In another embodiment, a seal layer (not shown) such as, for example, a hydrogel or other material may be disposed between the drape  122  and the epidermis  118  to augment or substitute for the sealing properties of the attachment device  130 . In one embodiment, the drape  122  and the bonding characteristics of the drape  122  provide sealing sufficient to prevent leakage greater than 0.5 L/min at 125 mmHg reduced pressure. 
     The reduced-pressure dressing  106  may further include a reduced-pressure interface  132  positioned adjacent to or coupled to the drape  122  to provide fluid access to the manifold  120 . Another attachment device (not shown) similar to the attachment device  130  may be used to hold the reduced-pressure interface  132  against the drape  122 . The first conduit  112 , the canister  110 , and the second conduit  114  fluidly couples the reduced-pressure treatment unit  108  and the reduced-pressure interface  132 . The reduced-pressure interface  132  allows the reduced pressure to be delivered to the tissue site  102 . While the amount and nature of reduced pressure applied to a tissue site will typically vary according to the application, the reduced pressure will typically be between −5 mm Hg (−667 Pa) and −500 mm Hg (−66.7 kPa) and more typically between −75 mm Hg (−9.9 kPa) and −300 mm Hg (−39.9 kPa). 
     The first and second conduits  112 ,  114  may be single lumen conduits, multi-lumen conduits, or a combination of a single lumen and multi-lumen conduit. In the instance either or both the first and second conduits  112 ,  114  are a multi-lumen conduit, one lumen may be a primary lumen and another lumen may be a sensing lumen for sensing the level of reduced pressure being applied to the tissue site  102 . Liquids or exudates communicated from the manifold  120  through the first conduit  112  are removed from the first conduit  112  and retained within the canister  110 . 
     The reduced-pressure treatment unit  108  includes a reduced-pressure source  134 , and may further include an instrumentation unit  136 . In an illustrative embodiment, the reduced-pressure source  134  is an electrically-driven vacuum pump. In another implementation, the reduced-pressure source  134  may instead be a manually-actuated or manually-charged pump that does not require electrical power. The reduced-pressure source  134  instead may be any other type of reduced pressure pump, or alternatively a wall suction port such as those available in hospitals and other medical facilities. The reduced-pressure source  134  may be housed within or used in conjunction with the reduced-pressure treatment unit  108 , which may also include the instrumentation unit  136 . The instrumentation unit  136  may include sensors, processing units, alarm indicators, memory, databases, software, display units, and user interfaces that further facilitate the application of reduced pressure treatment to the tissue site  102 . In one example, pressure-detection sensors (not shown) may be disposed at or near the reduced-pressure source  134 . The pressure-detection sensors may receive pressure data from the reduced-pressure interface  132  via lumens in the conduits  112 ,  114  that are dedicated to delivering reduced pressure data to the pressure-detection sensors. The pressure-detection sensors may communicate with a processing unit that monitors and controls the pressure that is delivered by the reduced-pressure source  134 . 
     Referring now primarily to  FIGS. 2-6 , the canister  110  shown in the system  100  of  FIG. 1  is presented in more detail. The canister  110  may be referred to as an in-line canister since the canister  110  is positioned between the first and second conduits  112 ,  114  that fluidly connect the reduced-pressure dressing  106  and the reduced-pressure treatment unit  108 . The canister  110  includes a center body  138 , a first end cap  140 , and a second end cap  142 . The canister  110  is configured to create a continuous, tortuous flow path represented by arrows  157 . The continuous, tortuous flow path is a unidirectional flow path. 
     The center body  138  includes a first end  144  and a second, opposing end  146 . A number of fluidly separate body conduits  148  extend from the first end  144  to the second end  146 . The number of fluidly separate body conduits  148  may be an uneven number. For example, the number of fluidly separate body conduits  148  may be 3, 5, 7, or more. As shown, the number of fluidly separate body conduits  148  is seven. The number may depend on the desired length of the continuous, tortuous flow path. In a specific example, the center body  138  may have a width, W, of approximately several inches, and more specifically, approximately 3 inches in some embodiments. The center body  138  may also have a length, L, between the first end and the second end  144 ,  146  of several inches in some embodiments. In more particular embodiments, the length L is approximately 6 inches. Each of the number of fluidly separate body conduits  148  may have a diameter, d, or a width that allows for an approximate canister  110  volumetric size of 170 cc. For example, in some embodiments, the diameter d is approximately 0.375 inches. It should be understood however, the width, W, and length, L, of the center body  138 , the number of body conduits  148  contained within the center body  138 , and the diameter, d, or width of the body conduits  148  may be adjusted according to the desired volumetric size of the canister  110 . 
     The center body  138  is shown as having an oblong shape with a first side  150  and a second, opposing side  152  that is both substantially planar and substantially parallel. It should be understood that while the center body  138  is shown as having an oblong shape with two sides that are substantially planar and parallel, the oblong shape is but one illustrative embodiment. The center body  138  may take a number of shapes. For example, the center body  138  may be rectangular, square, or cylindrical. A top  154  and a bottom  156  of the center body  138  may be rounded. Each of the number of fluidly separate body conduits  148  may be bonded together to form the center body  138 . In one embodiment, each of the number of fluidly separate body conduits  148  are bonded together in a single column. In another embodiment, the number of fluidly separate body conduits  148  are arranged in one or more columns or rows. In yet another embodiment, the center body  138  is a single extruded piece. The center body  138  may be formed of silicone or polyurethane, for example. The center body  138  may be made of a flexible material to make the center body less noticeable and more comfortable if worn under clothing. 
     The center body  138  may include an absorbent material (not shown) positioned within one or more of the number of fluidly separate body conduits  148 . The absorbent material may be one of a hydrophilic foam, a hydrophilic paper, a hydrophilic powder, or a sodium polyacrylate material. 
     The canister  110  further includes the first end cap  140 . The first end cap  140  is connected to the first end  144  of the center body  138 . The first end cap  140  may be connected to the center body  138  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the first end cap  140  and the center body  138 . The first end cap  140  may be formed as a single piece. The first end cap  140  may further be formed of silicone. 
     The first end cap  140  has a number of return conduits  158  configured to fluidly connect one of the body conduits  148  with another of the body conduits  148 . In one embodiment, the return conduits  158  connect two of the number of body conduits  148  that are adjacent. The return conduits  158  may function as turnabouts that redirect fluid received from one conduit into another conduit. The return conduits  158  may redirect fluid into an opposite direction. The first end cap  140  may include a number of protrusions (not shown) corresponding to the return conduits  158 . The number of protrusions would be insertable into the corresponding body conduits  148 . 
     The first end cap  140  has a port  160  for receiving an inlet conduit, such as the first conduit  112 , that is in fluid communication with the tissue site  102 . The first conduit  112  may be connected to the port  160  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the first conduit  112  and the port  160 . The port  160  is aligned with a first body conduit  170  of the number of body conduits  148  to facilitate fluid communication between the first conduit  112  and the first body conduit  170  of the number of body conduits  148 . 
     The canister  110  further includes the second end cap  142 . The second end cap  142  is connected to the second end  146  of the center body  138 . The second end cap  142  may be connected to the center body  138  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the second end cap  142  and the center body  138 . The second end cap  142  may be formed as a single piece. The second end cap  142  may further be formed of silicone. 
     The second end cap  142  has a number of return conduits  164  configured to fluidly connect one of the body conduits  148  with another of the body conduits  148 . In one embodiment, the return conduits  164  connect two of the number of body conduits  148  that are adjacent. The return conduits  164  may function as turnabouts that redirect fluid received from one conduit into another conduit. The return conduits  164  may redirect fluid into an opposite direction. The second end cap  142  may include a number of protrusions (not shown) corresponding to the return conduits  164 . The number of protrusions would be insertable into the corresponding body conduits  148 . 
     The second end cap  142  has a port  166  for receiving an outlet conduit, such as the second conduit  114 , that is in fluid communication with the reduced-pressure treatment unit  108  and, in particular, the reduced-pressure source  134 . The second conduit  114  may be connected to the port  166  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the second conduit  114  and the port  166 . The port  166  is aligned with an end conduit  194  of the number of body conduits  148  to facilitate fluid communication between the second conduit  114  and the end conduit  194  of the number of body conduits  148 . A hydrophobic filter (not shown) may be placed in the second end cap  142 , adjacent the port  166 , to prevent exudates from exiting the canister  110 . 
     In operation, reduced pressure is supplied to the tissue site  102  by the reduced-pressure treatment unit  108 . The canister  110  is a part of the system  100  that communicates the reduced pressure from the reduced-pressure treatment unit  108  to the tissue site  102 . While applying reduced pressure to the tissue site  102 , fluids, including liquids and exudates, may be removed from the tissue site  102 . The liquids and exudates removed from the tissue site  102  are collected and stored in the canister  110 . The fluid connection between the body conduits  148  and the return conduits  158 ,  164  of the first and second end caps creates a continuous, tortuous flow path that is represented by the arrows  157 . The continuous, tortuous flow path represented by the arrows  157  is a unidirectional flow path beginning at the port  160  in the first end cap  140  and ending at the port  166  in the second end cap  142 . The continuous, tortuous flow path passes through the each of the number of fluidly separate body conduits  148 . 
     Referring now primarily to  FIG. 6 , but also with reference to  FIGS. 2-5 , the number of body conduits  148  as shown is seven. The fluids removed from the tissue site  102  enter the canister  110  through the port  160  in the first end cap  140 . The fluids are delivered through the port  160  and into a first body conduit  170  of the number of body conduits  148 . The fluids may then flow through the first body conduit  170  to a first return conduit  172 , positioned in the second end cap  142 , and into a second body conduit  174 . The fluid from the second body conduit  174  may then flow into a second return conduit  176 , positioned in the first end cap  140 , and to a third body conduit  178 . The fluid from the third body conduit  178  may then flow into a third return conduit  180 , positioned in the second end cap  142 , and to a fourth body conduit  182 . The fluid from the fourth body conduit  182  may then flow into a fourth return conduit  184 , positioned in the first end cap  140 , and to a fifth body conduit  186 . The fluid from the fifth body conduit  186  may then flow into a fifth return conduit  188 , positioned in the second end cap  142 , and to a sixth body conduit  190 . The fluid from the sixth body conduit  190  may then flow into a sixth return conduit  192 , positioned in the first end cap  140 , and to a seventh body conduit  194 . Air and gases may pass through the port  166  positioned in the second end cap  142 . However, liquids and exudate will be trapped within the canister  110 . As used herein, “fluids” may include liquids, exudate, air, and other gases. 
     Referring now primarily to  FIGS. 7-11 , another illustrative embodiment of a canister  210  for use in a reduced-pressure treatment system such as the system  100  of  FIG. 1  is presented. The canister  210  is similar to the canister  110  shown in  FIGS. 1-6  except (i) the canister  210  includes three fluidly isolated body conduits  248  and (ii) a first end cap  240  and a second end cap  242  include protrusions  241 ,  243 , respectively. The canister  210  may be used for tissue sites that produce low volume exudates. 
     The canister  210  is positioned between the first and second conduits  112 ,  114  of  FIG. 1 . The canister  210  includes a center body  238 , the first end cap  240 , and the second end cap  242 . The canister  210  is configured to create a continuous, tortuous flow path represented by arrows  257 . The continuous, tortuous flow path is a unidirectional flow path. 
     The center body  238  includes a first end  244  and a second, opposing end  246 . The number of fluidly separate body conduits  248  extend from the first end  244  to the second end  246 . As shown, the number of fluidly separate body conduits  248  is three. The center body  238  may include an absorbent material (not shown) positioned within one or more of the number of fluidly separate body conduits  248 . The absorbent material may be one of a hydrophilic foam, a hydrophilic paper or a hydrophilic powder. 
     The first end cap  240  is connected to the first end  244  of the center body  238 . The first end cap  240  may be connected to the center body  238  by a connecting means such as an adhesive bond or a weld bond. The first end cap  240  may be formed as a single piece and may further be formed of silicone. 
     The first end cap  240  has a return conduit  258  configured to fluidly connect one of the body conduits  248  with another of the body conduits  248 . In one embodiment, the return conduit  258  connects two of the number of body conduits  248  that are adjacent. The return conduit  258  may function as a turnabout that redirects fluid received from one conduit into another conduit. The return conduit  258  may redirect fluid into an opposite direction. The first end cap  240  may include a number of protrusions  241  corresponding to the return conduit  258 . The number of protrusions  241  are configured to be inserted into the corresponding body conduits  248 . 
     The first end cap  240  has a port  260  for receiving an inlet conduit, such as the first conduit  112 , that is in fluid communication with the tissue site  102 . The port  260  is aligned with a first body conduit  262  of the number of body conduits  248  to facilitate fluid communication between the first conduit  112  and the first body conduit  262  of the number of body conduits  248 . 
     The second end cap  242  is connected to the second end  246  of the center body  238 . The second end cap  242  may be connected to the center body  238  by a connecting means such as an adhesive bond or a weld bond. The second end cap  242  may be formed as a single piece and may further be formed of silicone. 
     The second end cap  242  has a return conduit  264  configured to fluidly connect one of the body conduits  248  with another of the body conduits  248 . In one embodiment, the return conduit  264  connects two of the number of body conduits  248  that are adjacent. The return conduit  264  may function as a turnabout that redirects fluid received from one conduit into another conduit. The return conduit  264  may redirect fluid into an opposite direction. The second end cap  242  may include a number of protrusions  243  corresponding to the return conduit  264 . The number of protrusions  243  are configured to be inserted into the corresponding body conduits  248 . 
     The second end cap  242  has a port  266  for receiving an outlet conduit, such as the second conduit  114 , that is in fluid communication with the reduced-pressure treatment unit  108  and, in particular, the reduced-pressure source  134  of  FIG. 1 . The port  266  is aligned with an end conduit  268  of the number of body conduits  248  to facilitate fluid communication between the second conduit  114  and the end conduit  268  of the number of body conduits  248 . A hydrophobic filter (not shown) may be placed in the second end cap  242 , adjacent the port  266 , to prevent exudates from exiting the canister  210 . 
     Referring now primarily to  FIGS. 12A and 12B , another illustrative embodiment of a canister  310  for use in a reduced-pressure treatment system such as the system  100  of  FIG. 1  is presented. The canister  310  may be referred to as an in-line canister since the canister  310  is connected to the first and second conduits  112 ,  114  shown in  FIG. 1  that fluidly connect the reduced-pressure dressing  106  and the reduced-pressure treatment unit  108 . The canister  310  includes a center body  338 , a first end cap  340 , and a second end cap  342 . The canister  310  has a cylindrical shape. The canister  310  is configured to create a continuous, tortuous flow path. The continuous, tortuous flow path is a unidirectional flow path. 
     The center body  338  includes a first end  344  and a second, opposing end  346 . A number of fluidly separate body conduits  348  extend from the first end  344  to the second end  346 . The number of fluidly separate body conduits  348  may be an even or an uneven number. For example, the number of body conduits may be 8. The number may depend on the desired length of the continuous, tortuous flow path. The center body  338  may have a diameter, D, of approximately 1-2 inches in some embodiments. In more particular embodiments, the diameter D may be approximately 1.6 inches. The center body  338  may also have a length, L, between the first end and the second end  344 ,  346  of several inches in some embodiments, and approximately 4 inches in more particular embodiments. Each of the number of fluidly separate body conduits  348  may have a diameter, d, or a width of which allow for an approximate volumetric size of 130 cc. It should be understood however, the diameter, D, and length, L, of the center body  338 , the number of body conduits  348  contained within the center body  338 , and the diameter, d, or width of the body conduits  348  may be adjusted according to the desired volumetric size of the canister  310 . 
     The center body  338  is shown as having a cylindrical shape. The center body  338  includes an outer surface  351 . The outer surface  351  of the center body  338  may include a groove  353  that extends along the longitudinal axis, or the length, L, of the center body  338 . The groove  353  may be used during the manufacturing process to properly align the number of fluidly separate body conduits  348  within the center body  338 . The number of fluidly separate body conduits  348  may include a center conduit  339  and a number of outer body conduits  337  that are radially positioned around the center conduit  339 . The center body  338  may be a single extruded piece and may be formed of silicone. 
     The center body  338  may include an absorbent material (not shown) positioned within one or more of the number of fluidly separate body conduits  348 . The absorbent material may be one of a hydrophilic foam, a hydrophilic paper or a hydrophilic powder. 
     The canister  310  further includes the first end cap  340 . The first end cap  340  is connected to the first end  344  of the center body  338 . The first end cap  340  may be connected to the center body  338  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the first end cap  340  and the center body  338 . The first end cap  340  may be formed as a single piece. The first end cap  340  may further be formed of silicone. 
     The first end cap  340  includes a first plenum  355  for receiving fluids. The first plenum  355  may have a number of return conduits  358  positioned within the first plenum  355 . The return conduits  358  are configured to fluidly connect one of the body conduits  348  with another of the body conduits  348 . The return conduits  358  may function as turnabouts that redirect fluid received from one conduit into another conduit. The return conduits  358  may redirect fluid into an opposite direction. The first end cap  340  may include a number of protrusions  341  corresponding to the return conduits  358 . The number of protrusions  341  are configured to be insertable into the corresponding body conduits  348 . 
     The first end cap  340  has an inlet port  360  for receiving an inlet conduit, such as the first conduit  112 , and an outlet port  366  for receiving an outlet conduit, such as the second conduit  114 . The inlet conduit, or the first conduit  112 , is in fluid communication with the tissue site  102 , and the outlet conduit, or the second conduit  114 , is in fluid communication with the reduced-pressure source  134 . The first conduit  112  may be connected to the inlet port  360  and the second conduit  114  may be connected to the outlet port  366  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the first conduit  112  and the inlet port  360  and the second conduit  114  and the outlet port  366 . The inlet port  360  is aligned with one of the number of body conduits  348 . In one embodiment, the inlet port  360  is aligned with one of the number of outer body conduits  337  such as a first body conduit  362 . In another embodiment, the inlet port is aligned with the center conduit  339 . The inlet port  360  aligns with one of the number of body conduits  348  to facilitate fluid communication between the first conduit  112  and the one of the number of body conduits  348 . The inlet port  360  may include a protrusion  359  for inserting into the one of the number of body conduits  348 . The outlet port  366  is aligned with another of the number of body conduits  348 . In one embodiment, the outlet port  366  is aligned with the center conduit  339 . In another embodiment, the outlet port  366  is aligned with one of the radial body conduits such as the first body conduit  362 . The outlet port  366  aligns with another of the number of body conduits  348  to facilitate fluid communication between the second conduit  114  and another of the number of body conduits  348 . A hydrophobic filter (not shown) may be placed in the first end cap  340 , adjacent the outlet port  366 , to prevent exudates from exiting the canister  310 . 
     The canister  310  further includes the second end cap  342 . The second end cap  342  is connected to the second end  346  of the center body  338 . The second end cap  342  may be connected to the center body  338  by a connecting means such as an adhesive bond or a weld bond. The connecting means creates a fluid seal between the second end cap  342  and the center body  338 . The second end cap  342  may be formed as a single piece. The second end cap  342  may further be formed of silicone. 
     The second end cap  342  includes a second plenum  357  for receiving fluids. The second end cap  342  has a number of return conduits  364  positioned within the second plenum  357 . The return conduits  364  are configured to fluidly connect one of the body conduits  348  with another of the body conduits  348 . The return conduits  364  may function as turnabouts that redirect fluid received from one body conduit into another body conduit. The return conduits  364  may redirect fluid into an opposite direction. The second end cap  342  may include a number of protrusions  343  corresponding to the return conduits  364 . The number of protrusions would be insertable into the corresponding body conduits  348 . 
     In operation, reduced pressure is supplied to the tissue site  102  by the reduced-pressure treatment unit  108 . The canister  310  is a part of the system  100  that communicates the reduced pressure from the reduced-pressure treatment unit  108  to the tissue site  102 . While applying reduced pressure to the tissue site  102 , fluids, including liquids and exudates, may be removed from the tissue site  102 . The liquids and exudates removed from the tissue site  102  are collected and stored in the canister  310 . The fluid connection between the body conduits  348  and the return conduits  358 ,  364  of the first and second end caps creates a continuous, tortuous flow path. The continuous, tortuous flow path is a unidirectional flow path beginning at the inlet port  360  in the first end cap  340  and ending at the outlet port  366  in the first end cap  340 . The continuous, tortuous flow path passes through the each of the number of fluidly separate body conduits  348 . 
     In one illustrative, non-limiting embodiment, the fluids removed from the tissue site  102  enter the canister  310  through the inlet port  360  in the first end cap  340 . The fluids are delivered through the inlet port  360  and into a first body conduit  362  of the number of body conduits  348 . The fluids may then flow through the first body conduit  362  to a first return conduit  372 , positioned in the second end cap  342 , into a second body conduit  374 . The fluid from the second body conduit  374  may then flow into a second return conduit  376 , positioned in the first end cap  340 , to a third body conduit  378 . The fluid from the third body conduit  378  may then flow into a third return conduit  380 , positioned in the second end cap  342 , to a fourth body conduit  382 . The fluid from the fourth body conduit  382  may then flow into a fourth return conduit  384 , positioned in the first end cap  340 , to a fifth body conduit  386 . The fluid from the fifth body conduit  386  may then flow into a fifth return conduit  388 , positioned in the second end cap  342 , to a sixth body conduit  390 . The fluid from the sixth body conduit  390  may then flow into a sixth return conduit  392 , positioned in the first end cap  340 , to a seventh body conduit  394 . The fluid from the seventh body conduit  394  may then flow into a seventh return conduit or end conduit  396  positioned in the second end cap  342 , to the center conduit  339 . Air and gases may pass through the outlet port  366  positioned in the first end cap  340 . However, liquids and exudate will be trapped within the canister  310 . In this embodiment, fluid received by the inlet port  360  travels through each of the outer body conduits  337  prior to reaching the center conduit  339  and traveling towards the outlet port  366 . 
     Referring now primarily to  FIGS. 13A and 13B , another illustrative embodiment of a canister  410  for use in a reduced-pressure treatment system such as the system  100  of  FIG. 1  is presented. The canister  410  is similar to the canister  310  shown in  FIGS. 12A and 12B  except a first and second end cap  440 ,  442  do not include return conduits. 
     The canister  410  includes a center body  438 , a first end cap  440 , and a second end cap  442 . The canister  410  has a cylindrical shape and is configured to create a tortuous flow path. The center body  438  includes a first end  444  and a second, opposing end  446 . A number of fluidly separate body conduits  448  extend from the first end  444  to the second end  446 . The center body  438  includes an outer surface  451 . The outer surface  451  of the center body  438  may include a groove  453  that extends along the longitudinal axis, or the length of the center body  438 . The number of fluidly separate body conduits  448  may include a center body conduit  439  and a number of outer body conduits  437  that are radially positioned around the center body conduit  439 . The center body  438  may be a single extruded piece and may be formed of silicone. 
     The center body  438  may include an absorbent material (not shown) positioned within one or more of the number of fluidly separate body conduits  448 . The absorbent material may be one of a hydrophilic foam, a hydrophilic paper or a hydrophilic powder. 
     The canister  410  further includes the first end cap  440 . The first end cap  440  is connected to the first end  444  of the center body  438 . The first end cap  440  may be connected to the center body  438  by a connecting means such as an adhesive bond or a weld bond. The first end cap  440  may be formed as a single piece and may further be formed of silicone. 
     The first end cap  440  includes a first plenum  455  for receiving fluids. The first end cap  440  has an inlet port  460  for receiving an inlet conduit, such as the first conduit  112 , and an outlet port  466  for receiving an outlet conduit, such as the second conduit  114 . The inlet conduit, or the first conduit  112 , is in fluid communication with the tissue site  102 , and the outlet conduit, or the second conduit  114 , is in fluid communication with the reduced-pressure source  134 . The first conduit  112  may be connected to the inlet port  460  and the second conduit  114  may be connected to the outlet port  466  by a connecting means such as an adhesive bond or a weld bond. In one embodiment, the inlet port  460  is in fluid communication with all but one of the number of body conduits  448 . For example, the inlet port  460  may be in fluid communication with the outer body conduits  437 . In this example, the outlet port  466  is in fluid communication with the center body conduit  439 . The outlet port  466  may include a protrusion configured to be positioned within the center body conduit  439 . The first plenum  455  is an open space or cavity. Fluids received by the inlet port  460  enter the first plenum  455  and are distributed to the outer body conduits  437 . The fluids pass through the outer body conduits  437  and enter the second end cap  442  having a second plenum  457 . 
     The second end cap  442  is connected to the second end  446  of the center body  438 . The second end cap  442  may be connected to the center body  438  by a connecting means such as an adhesive bond or a weld bond. The second end cap  442  may be formed as a single piece and may further be formed of silicone. The second end cap  442  includes the second plenum  457  for receiving fluids. The second plenum  457  is an open space or cavity that receives fluids from one or more of the number of body conduits  448  in fluid communication with the inlet port  460  such as the outer body conduits  437 . Fluid received by the second plenum  457  is directed into the center body conduit  439  and to the outlet port  466 . Fluid in the second plenum  457  may be directed into the center body conduit  439  by means of reduced pressure. 
     In another embodiment (not shown), the inlet port  460  is fluidly connected with one of the number of body conduits  448 . The inlet port  460  aligns with one of the number of body conduits  448  to facilitate fluid communication between the first conduit  112  and the one of the number of body conduits  448 . The inlet port  460  may include a protrusion for inserting into the one of the number of body conduits  448 . The outlet port  466  is aligned with the other conduits of the number of body conduits  448 . 
     In operation, reduced pressure is supplied to the tissue site  102  by the reduced-pressure treatment unit  108 . The canister  410  is a part of the system  100  that communicates the reduced pressure from the reduced-pressure treatment unit  108  to the tissue site  102 . While applying reduced pressure to the tissue site  102 , fluids, including liquids and exudates, may be removed from the tissue site  102 . The liquids and exudates removed from the tissue site  102  are collected and stored in the canister  410 . The fluid connection between the body conduits  448  and the first and second end caps  440 ,  442  creates a tortuous flow path having several parallel paths. The tortuous flow path begins at the inlet port  460  in the first end cap  440  and ends at the outlet port  466  in the first end cap  440 . The tortuous flow path passes through each of the number of body conduits  448 . 
     In one illustrative, non-limiting embodiment, the fluids removed from the tissue site  102  enter the canister  410  through the inlet port  460  in the first end cap  440 . The fluids are delivered through the inlet port  460  into the first plenum  455 . The fluid is then directed to any one of the outer body conduits  437 . The fluid is received by the second plenum  457  and directed into the center body conduit  439 . 
     It should be apparent from the foregoing that an invention having significant advantages has been provided. While the invention is shown in only a few of its forms, it is not just limited but is susceptible to various changes and modifications without departing from the spirit thereof.