Patent Publication Number: US-2021170117-A1

Title: Active smoke filtration for insufflation

Description:
INCORPORATION BY REFERENCE TO ANY PRIORITY APPLICATIONS 
     Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57. 
     BACKGROUND 
     Technical Feld 
     The present disclosure generally relates to active smoke filtration units for use during laparoscopic surgery. More particularly, the present disclosure relates to an active smoke filtration unit that is part of a generally closed recirculation circuit within a laparoscopic surgery insufflation system. 
     Description of the Related Art 
     In some systems used for laparoscopic surgery, the gases delivered to the patient are conditioned prior to delivery to the patient. In some such systems, the gases are heated and humidified prior to delivery to the patient. For example, a humidification system can be placed between an insufflator and a surgical cannula. As gases travel towards the patient, the gases are humidified, and heated and/or insulated tubing ensures humidity is not lost before the gases reach the patient. 
     During laparoscopic surgery, smoke and other debris can be produced as a result of the cautery process, for example but without limitation. The smoke can form within the body cavity and can cloud the vision provided to the surgeon through an endoscopic camera that is positioned to view inside the body cavity. 
     SUMMARY 
     It is desirable to remove such smoke to improve the vision of the surgeon. It is possible to vent the body cavity and thereby remove smoke. However, maintaining the pressure within the body cavity also is desired. It is also desirable to recirculate and thus reuse insufflation gases, such as carbon dioxide, which reduces overall consumption of such gases and allows for the use of smaller gas containers. 
     By recirculating and filtering the conditioned insufflation gases used during laparoscopic surgery, the debris and smoke from the cautery process can be removed. While filtration apparatus and techniques have been used in the past, those apparatus and techniques have proven to be inefficient, noisy, and less effective than desired. 
     Accordingly, an improved active filtration system and unit has been developed. The system is considered active because an apparatus such as a compressor, for example but without limitation, is used to create a recirculating flow of insufflation gases through the body cavity. Recirculation of insufflation gases reduces the likelihood of pressure loss during the filtration process. In addition, recirculation of insufflation gases can be viewed as an improvement over a passive system that simply vents the insufflation gases out of the body cavity of the patient to the atmosphere. 
     By recirculating the insufflation gases in a recirculation circuit that is disposed both inside and outside of the body of the patient, a larger filter can be used than would otherwise be possible to use within the body. Also, when the circuit includes a humidifier, moisture can be maintained within the system, thereby reducing the volume of water used to adequately humidify the gases. A humidifier can heat and humidify the insufflation gases, which can help to reduce disruption to the cellular layer of the peritoneum, thereby mitigating desiccation and subsequent complications such as adhesions, tumor metastasis, and other temperature-related complications. 
     Recirculating insufflation gases outside of the body of the patient, however, can pose certain challenges, especially when the insufflation gases are conditioned. For example, recirculating gases outside of the body can result in cooling of the gases, which is counter to the goal of heating and humidifying the gases. Entrainment of room air into the recirculation circuit can also result in cooling and drying of the insufflation gases. Moreover, cooling of heated and humidified gases can result in condensation, and condensation can inhibit effective recirculation and/or cloud the vision of the surgeon inside the body cavity. 
     According to some aspects of the present disclosure, a system for use during laparoscopic surgery comprises a recirculation circuit having an inlet and an outlet. The inlet is configured to connect to a body cavity and the outlet is configured to connect to a gases conduit between a primary flow generator and a connection to the body cavity. The system also comprises a pneumatic isolation feature configured to be positioned between the recirculation circuit and the primary flow generator. The pneumatic isolation feature is in fluid communication with the recirculation circuit. The system further comprises an active filtration unit that is positioned along the recirculation circuit. The active filtration unit comprises a flow generator portion and a filtration portion. The flow generator portion comprises an inlet and an outlet and is configured to create a pressure differential between the inlet and the outlet. The filtration portion comprises a filter adapted to remove smoke and other debris from a gases flow through the recirculation circuit. The system also comprises a condensate management system positioned along the recirculation circuit. 
     The pneumatic isolation feature can comprise a set of valves. The set of valves can comprise a one-way valve and an overpressure valve. The pneumatic isolation feature can comprise a pressure dampener. 
     A humidifier can be positioned along a flow path between the primary flow generator and the connection to the body cavity. The humidifier can be positioned along the flow path between the pneumatic isolation feature and the connection to the body cavity. The humidifier can be positioned along the flow path between the outlet of the recirculation circuit and the body cavity such that gases coming from the recirculation circuit pass through the humidifier before returning to the body cavity. The pneumatic isolation feature can be positioned along the flow path between the humidifier and the connection to the body cavity. The recirculation circuit can be positioned in the flow path between the humidifier and the connection to the body cavity. The recirculation circuit can be positioned in the flow path between the pneumatic isolation feature and the connection to the body cavity. The recirculation circuit can be positioned in the flow path to recirculate insufflation gases without entrainment of room air into the insufflation system. 
     The filter can be disposed between an inlet to the active filtration unit and the flow generator portion. The condensate management system can be positioned upstream of the filter. The condensate management system can comprise a water trap. The water trap can be reusable. The condensate management system can comprise a condenser. The condensate management system can comprise a film or foamed breathable polymer. The film or foamed breathable polymer can comprise a conduit. The condensate management system can comprise a canister. The canister can contain a substance with an affinity to water. The substance can comprise a foam material. The substance can comprise a chemical that absorbs water. The condensate management system can comprise a desiccant that is located with the filtration portion. The condensate management system can comprise a heated conduit. The condensate management system can comprise a tube containing an absorbent material. The absorbent material can comprise a sponge or foam. 
     The flow generator portion can comprise a pump. The pump can comprise a diaphragm compressor. The pump can comprise a radial compressor. The pump can comprise a peristaltic pump. The pump can comprise two interconnected rotors. 
     According to some aspects of the present disclosure, an active filtration unit configured for use during laparoscopic surgery comprises a filtration portion and a flow generator portion that are positioned in a flow path defined within a housing. The housing comprises an inlet, an outlet, at least a part of the filtration portion, and at least a part of the flow generator portion. The flow path is defined between the inlet and the outlet. 
     The flow path can be at least partially heated. 
     A system can comprise a primary flow generator and a recirculation circuit comprising the active filtration unit. The system can comprise a humidifier fluidly coupled to the primary flow generator by a supply conduit and fluidly coupled to the recirculation circuit by at least one tube. The system can comprise a condensate management system. The condensate management system can be at least partially defined within the housing of the active filtration unit. The primary flow generator can comprise an insufflator. A valve assembly can be positioned between the primary flow generator and the recirculation circuit. The valve assembly can comprise a check valve. The valve assembly can comprise an overpressure valve. 
     According to some aspects of the present disclosure, a recirculating filtration unit configured for use during laparoscopic surgery comprises a filtration portion, a flow generator portion, and a valve assembly that are positioned in a flow path defined within a housing. The housing comprises an inlet, an outlet, the valve assembly, at least a part of the filtration portion, and at least a part of the flow generator portion. The flow path is defined between the inlet and the outlet. 
     The flow path can be at least partially heated. The valve assembly can comprise a check valve. The valve assembly can comprise an overpressure valve. 
     A system can comprise a primary flow generator and a recirculation circuit comprising the recirculating filtration unit. The system can comprise a humidifier fluidly coupled to the primary flow generator by a supply conduit and fluidly coupled to the recirculation circuit by at least one tube. The system can comprise a condensate management system. The condensate management system can be at least partially defined within the housing of the recirculating filtration unit. The primary flow generator can comprise an insufflator. 
     Certain features, aspects and advantages of the apparatus and systems disclosed herein can be used with heated and humidified or otherwise conditioned insufflation systems, with non-conditioned insufflation systems, and with other systems used for laparoscopic surgery applications. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Specific embodiments and modifications thereof will now be described with reference to the following figures. 
         FIG. 1  is a schematic illustration of a first insufflation system. 
         FIG. 2  is a schematic illustration of a second insufflation system. 
         FIG. 3  is an illustration of a smoke filtration unit. 
         FIG. 4  is a schematic view of a motorless pump having two interconnected rotors. 
         FIG. 5  is a schematic view of a diaphragm pump. 
         FIG. 6  is a schematic view of a peristaltic pump. 
         FIG. 7  and  FIG. 8  are schematic views of a radial compressor. 
         FIG. 9  is a schematic view of a pressure dampener. 
     
    
    
     DETAILED DESCRIPTION 
     With reference now to  FIG. 1 , an example insufflation system  10  that comprises an active filtration unit  12  is illustrated schematically. In some configurations, the active filtration unit  12  is specifically configured to be disposable (i.e., a consumable product). In other configurations, the active filtration unit  12  can be integrated into other components and/or be sterilizable. 
     The illustrated insufflation system  10  comprises a primary flow generator  14 . The primary flow generator  14  can be designed and configured to control at least one of the pressure and the flow rate of gases that will be supplied to the patient during use. The primary flow generator  14  can have any suitable configuration. In some configurations, the primary flow generator  14  can comprise a compressed gases cylinder and a regulator valve assembly. In some configurations, the primary flow generator  14  can comprise a pump that supplies insufflation gases. The primary flow generator  14  can provide a flow rate of less than 45 L/min of insufflation gases. Such configurations are particularly suited for laparoscopic procedures. The primary flow generator  14  can comprise an insufflator. The insufflator  14  can comprise an alarm system to warn of gases overpressure events or pressure spikes during a laparoscopic procedure. The insufflation gases can comprise carbon dioxide, for example but without limitation. The insufflator can be provided separate of and connected to the other components of the system (for example, the active filtration unit  12 ). 
     To reduce the likelihood of cold, dry gases supplied by the primary flow generator  14  damaging the peritoneum or other body tissues during a surgical procedure, the illustrated insufflation system  10  comprises a humidifier  16 . The humidifier  16  can have any suitable configuration. In some configurations, the humidifier  16  features a chamber  18  that contains a liquid (for example, water) and a heating element (for example, a beater plate) that is associated with the chamber  18 . In some such configurations, the humidifier  16  can be a humidifier supplied by Fisher &amp; Paykel Healthcare Ltd. known as the MR860 humidifier. In some configurations, the humidifier  16  provides humidification to the system and takes the form of an absorbent material that releases humidity, water vapor or the like into the gases flow. The humidifier  16  can heat and/or humidify the cold, dry gases supplied by the primary flow generator  14 . By heating and/or humidifying the cold, dry gases, the peritoneum of a patient can better remain warm and moist during an operation, which can reduce disruption to the cellular layer of the peritoneum by mitigating desiccation and subsequent complications such as adhesions, tumor metastasis, and other temperature-related complications. 
     In some configurations, the humidifier  16  can be positioned between the primary flow generator  14  and a delivery component  20  through which heated and/or humidified gases can be introduced to the patient. In some configurations, the delivery component  20  can comprise a cannula, such as a Veress needle, which is a spring-loaded needle used to create pneumoperitoneum for laparoscopic surgery. In other configurations, the delivery component  20  can comprise any suitable apparatus through which heated and/or humidified gases can be introduced to the patient. 
     The primary flow generator  14  can be connected to an inlet of the humidifier  16  with a supply conduit  22 . The supply conduit  22  can be any conduit suitable to transport cold, dry gases from the primary flow generator  14 . The supply conduit  22  can be a single section of tubing or can be multiple sections of tubing connected together to define a gases delivery channel from the primary flow generator  14  to the humidifier  16 . 
     A filter  24  can be positioned along the supply conduit  22  at a location between the primary flow generator  14  and the humidifier  16 . In some configurations, the filter  24  can be a mechanical filter. In some configurations, the filter  24  can be a high-efficiency bacterial filter. In some configurations, the filter  24  is a pleated mechanical HEPA filter. In some configurations, the efficiency of the filter  24  can be BFE 99.9999%, VFR 99.9999% with a filtration ability of 0.3 micron. In some configurations, the filter  24  is hydrophobic. In some configurations, the filter  24  can incorporate a 15 mm connection and a 22 mm connection. In some configurations, a barb adaptor also can be included with the filter  24 . In other configurations, the filter  24  can comprise any suitable apparatus to filter the gases transported by the supply conduit  22 . 
     An outlet of the humidifier  16  can be connected to the delivery component  20  using an insufflation conduit  26 . The insufflation conduit  26  can be thermally insulated and/or can be heated. In some configurations, the insufflation conduit  26  can incorporate a heater element that wraps around a wall of the insufflation conduit  26 . The heater element can be positioned outside of the wall, outside of the lumen, inside of the wall or inside of the lumen of the insufflation conduit  26 . By using a heated and/or insulated insufflation conduit  26 , the temperature and/or humidity of the conditioned gases can be better maintained during transit from the humidifier  16  to the delivery component  20 . The insufflation conduit  26  can be a single section of tubing or can be multiple sections of tubing connected together to define a gases delivery channel from the humidifier  16  to the delivery component  20  keeping in mind a desire to supply the conditioned gases at or above the dew point temperature. 
     In some configurations, the insufflation conduit  26  can be connected to the delivery component  20  using a connector. In some such configurations, the connector can comprise a rotating luer lock. In some such configurations, the rotating luer lock can be a standard luer fitting compatible with ISO 594-1:1986 and ISO 594-2:1998. 
     As illustrated in  FIGS. 1 and 2 , the active filtration unit  12  can be disposed along a recirculation circuit  28 . In some configurations, such as that shown in  FIG. 1 , the recirculation circuit  28  can extend between the patient and the supply conduit  22 . In the configuration of  FIG. 1 , the recirculation circuit  28  connects to the supply conduit  22  at a location between the filter  24  and the humidifier  16 . As such, the illustrated recirculation circuit  28  does not include the bacterial filter  24 . As illustrated, the humidifier  16  can be positioned within the recirculation circuit  28  (see  FIG. 1 ). In some configurations, the humidifier  16  is positioned not within the recirculation circuit (see  FIG. 2 ). Accordingly, as shown in  FIG. 2 , the recirculation circuit  28  can extend between the patient and the insufflation conduit  26 , which bypasses both the bacterial filter  24  and the humidifier  16 . When the humidifier  16  is positioned within the recirculation circuit  28 , humidity can be added to the recirculating gases before the gases are reintroduced to the body cavity. When the humidifier  16  is positioned not within the recirculation circuit  28  (see  FIG. 1 ), then the gases being reintroduced to the body may have less humidity, which can improve the optical clarity. 
     In some configurations, the recirculation circuit  28  comprises a tube  30  that is configured to interconnect the patient with the supply conduit  22  or the insufflation conduit  26 . The tube  30  can comprise one or more sections of tubing. In some configurations, a first section  32  of the tube  30  interconnects the active filtration unit  12  with the patient and a second section  34  of the tube  30  interconnects the active filtration unit  12  with the supply conduit  22  ( FIG. 1 ) or the insufflation conduit  26  ( FIG. 2 ). 
     In some configurations, the tube  30  is insulated. In some configurations, the tube  30  comprises a heating element. The heating element can be positioned outside of the wall of the tube  30 , inside of the wall of the tube  30 , outside of the lumen of the tube  30  and/or inside of the lumen of the tube  30 . As the gases being withdrawn from the body cavity have a high humidity content, the heating element can reduce or eliminate the likelihood of condensation of the water vapour as the gases are transported through the tube  30 . In some configurations, the heating element of the tube  30  is in electrical communication with the heating element of the insufflation conduit  26 . In some configurations, the heating element of the tube  30  is controlled by a controller that also controls the heating element of the insufflation conduit  26 . In some configurations, the controller controls the heating element of the tube  30  separately of the heating element of the insufflation conduit  26 . In some configurations, the controller controls the heating element of the tube  30  together with the heating element of the insufflation conduit  26 . In some configurations, the controller forms a portion of the humidifier  16 . In some configurations, the controller forms a portion of the primary flow generator  14 . In some configurations, the controller forms a portion of the active filtration unit  12 . In some configurations, the controller is separate from the primary flow generator  14 , the humidifier  16 , and the active filtration unit  12 . 
     As discussed above, by insulating End/or heating portions of the tube  30  (e.g., one or both of the first section  32  and the second section  34 ), the conditioned gases that have been delivered to the patient are less likely to cool in transit to and/or from the active filtration unit  12 . Accordingly, in configurations in which one or both of the first section  32  and the second section  34  of the tube  30  are insulated and/or heated, the moisture present within the conditioned gases is less likely to condense during transit through the recirculation circuit  28 . The conditioned gases are also less likely to drop in temperature or humidity while flowing through the recirculation circuit  28  because the insufflation gases are recirculated without entrainment of room air. In some configurations, the dew point temperature of the recirculating gases is exceeded throughout the recirculation circuit  28 . 
     With reference now to  FIG. 3 , the active filtration unit  12  generally comprises a filtration portion  40  and a flow generator portion  42  that can be connected by a flow connector  43 . While the illustrated configuration features an integrated unit having both the filtration portion  40  and the flow generator portion  42 , it is possible to separate the filtration portion  40  and the flow generator portion  42  into two separate units. In some configurations, the filtration unit  12  is configured to reduce noise. For example, the flow generator portion  42  can be mechanically isolated from the other components of the active filtration unit  12 . In some configurations, the flow generator portion  42 , which includes a flow generator, pump, or the like, can be physically or mechanically decoupled from a housing of the active filtration unit. In some configurations, the flow generator portion  42  can be muffled, surrounded, enclosed, enveloped, or isolated using a sound absorbing material. Other configurations also are possible. 
     The active filtration unit  12  also comprises an inlet  44  and an outlet  46 . Gases am drawn in from the patient to the active filtration unit  12  through the inlet  44  and returned toward the patient through the outlet  46 . In the illustrated configuration, the filtration portion  40  is positioned between the inlet  44  and the flow generator portion  42 . In some configurations, the flow generator portion  42  can be positioned between the inlet  44  and the filtration portion  40 . 
     In some configurations, at least a portion of a flow path through the active filtration unit  12  between the inlet  44  and the outlet  46  can be heated. In some configurations, only the filtration portion  40  is heated. In some configurations, the flow generator portion  42  is heated. In some configurations, a majority of the flow path between the inlet  44  and the outlet  46  can be heated. In some configurations, almost the entire flow path through the active filtration unit  12  can be heated. In some configurations, the entire flow path from the inlet  44  to the outlet  46  can be heated. 
     The active filtration unit  12  comprises a housing  48 . The housing  48  can be configured to be clipped onto a drape or other component within the operating theater. In some configurations, the active filtration unit  12  and/or the tube  30  that is attached to the active filtration unit  12  can be draped over the patient in the operating theater. The housing  48  in the illustrated configuration defines the inlet  44 , the outlet  46 , and the internal passages between the inlet  44  and the outlet  46 . The housing  48  generally encloses the flow generator portion  42 . The housing  48  generally encloses the filtration portion  40 . 
     The active filtration unit  12  creates pressure differences that cause gases to flow through the recirculation circuit  28 . To create the desired pressure differences, the flow generator portion  42  can be a compressor or the like. Because the active filtration unit  12  works by creating pressure differences, the illustrated active filtration unit  12  may only work with some types of insufflators. In some configurations, the flow generator portion  42  can be configured similarly to the configuration shown and described in U.S. Provisional Patent Application No. 61/738,910, filed on Dec. 18, 2012 and entitled Impeller and Motor Assembly, or U.S. Provisional Patent Application No. 61/507,384, filed Jul. 13, 2011 and entitled Impeller and Motor Assembly, each of which is hereby incorporated by reference in its entirety. 
     In some configurations, the flow generator can be a pump  60  (for example, a peristaltic pump, a radial compressor, a diaphragm compressor, a rotor system, or the like). In some configurations, the pump  60  can be incorporated into the primary flow generator  14 . In some configuration, the pump  60  can be incorporated into the insufflator. In some configurations, the pump  60  is designed to be positioned outside of a sterile zone. As used herein, “sterile zone” means an area within an operating theatre/clinic within which only sterile equipment can be used, and into which only those personnel who have gone through surgical scrubbing and the gowning process can enter. In some configurations, the insufflation system  10  can be configured such that the pump  60  will be positioned within the sterile zone. 
     In configurations where the active filtration unit  12  has a pump  60  positioned within the sterile zone, the pump  60  (and/or any other portion of the active filtration unit  12  designed to be positioned within the sterile zone) is either disposable (that is, a single use pump) or capable of being repeatedly sterilized (for example, through the use of steam autoclave or dry heat oven) so that it can be re-sterilized between uses. If configured to be a single use pump, the gas flow path would need to be sterile. In some such configurations, the gas flow path can be decoupled from the motor or other operating component that may be in direct contact with the gas flow path. 
     In some configurations, the flow generator portion  42  can comprise an impeller. A motor  50  can be used to drive the impeller. The flow generator portion  42 , and the active filtration unit  12  in general, can be powered from mains or can be battery powered. An electrical cable  52  can be used to provide power and/or control signals and can be connected to the motor  50 . 
     The motor  50  may be any motor suitable for generating high flow rates. In some configurations, the flow generator portion  42  is rated for high flow rates to overcome pressure in the system. In other words, high flow rates are desired to achieve a recirculating flow of gases in the active filtration unit  12  and the recirculation circuit  28 . In the illustrated configuration, the motor  50  (in combination with the impeller and related flow paths within the housing  48 ) creates a pressure differential between the inlet  44  and the outlet  46  to generate a flow of gases that removes smoke from a body cavity of a patient. 
     Use of the motor  50  can increase the cost of the system, particularly when a single use pump  60  is desired. With reference to  FIG. 4 , a pump is illustrated that includes two rotationally connected rotors  62   a ,  62   b . Chambers  66   a ,  66   b  can be separated by a wall or other dividing member  68 . The two chambers  66   a ,  66   b  preferably are sealed from each other such that gases cannot be exchanged between the two chambers  66   a ,  66   b . Bach of the chambers includes an inlet  70   a ,  70   b  and an outlet  72   a ,  72   b . The flow of the recirculation circuit  28  passes through the first chamber  66   a  while a secondary flow from another system passes through the second chamber  66   b . For example, the secondary flow can be created by a suction source such as an in-theatre source or a compressed bottle. 
     In some configurations, the first rotor  62   a  is positioned in the first chamber  66   a  while the second rotor  62   b  is positioned in the second chamber  62   b . The two rotors  62   a ,  62   b  are connected by a shaft  76 . In some configurations, a gear train, a magnetic coupling or the like also can be used to connect the two rotors  62   a ,  62   b  keeping in mind a desire for one of the rotors  62   b  to drive the other of the rotors  62   a . For example, the magnetic coupling can allow rotational coupling without a direct physical coupling, which simplifies isolating the gases in the first chamber  66   a  from the gases in the second chamber  66   b.    
     The secondary flow will drive the second rotor  62   b . Because the second rotor  62   b  and the first rotor  62   a  are joined for rotational movement, the first rotor  62   a  will be driven by the second rotor  62   b . Rotation of the first rotor  62   a  causes flow within the recirculation circuit  28 . Accordingly, in the illustrated configuration, no motor is required, which allows for a less expensive pump and one that can be designed to be a single use pump. In some configurations, only the components that come into contact with the flow of the recirculation circuit  28  are designed to be single use, whilst the remaining components of the pump can be reused. 
     With reference now to  FIG. 5 , a diaphragm compressor  80  is illustrated. The diaphragm compressor  80  can be used as the pump  60 . In some configurations, at least a portion of the diaphragm compressor  80  can be configured for single use. For example, the diaphragm compressor  80  comprises a drive portion  82  and a flow generator portion  84 . The drive portion  82  can include a piston  86  that is connected to the flow generator portion  84 . The piston  86  can be moved in any suitable manner. In the illustrated configuration, a the piston  86  is connected to a motor  90 . The motor  90  can be a rotary motor. The motor  90  can be an electric motor. The piston  86  and the motor  90  are not in communication with the gases of the recirculation circuit  28 . Rather, only the flow generator portion  84  is in fluid communication with the gases of the recirculation circuit  28 . Accordingly, the piston  86  and the motor  90  can be reused. 
     The flow generator portion  84  can be configured to be one-time or single use. In some configurations, the flow generator portion  84  can be configured as a disposable cartridge  94  or the like. The flow generator portion  84  can include an inlet  96  and an outlet  98 . The inlet  96  and the outlet  98  can be connected to a chamber  100  that includes a diaphragm  102 . Check valves  104 ,  106  or one-way valves can be included along the flow path through the flow generator portion  84  to help direct flow through the flow generator portion  84  of the diaphragm compressor  80 . Movement of the diaphragm  102  acts to pull gases into the chamber  100  and then expel the gases from the chamber  100 . While the diaphragm compressor  80  does incorporate the motor  90 , and thus has a higher initial cost than the dual rotor design discussed above, the use of a disposable cartridge  94  that includes the chamber  100 , the inlet  96 , the outlet  98  and the diaphragm  102  allows for a simple and cost effective single use design. 
     With reference to  FIG. 6 , a peristaltic pump  110  is illustrated that can be used as the pump  60  of the active filtration unit  12 . The pump  110  includes a disposable length of tubing  112 . As illustrated, the tubing  112  can be positioned within a chamber  116 . The chamber  116  can include a rotary member  118 . The rotary member  118  and a wall  122  within the chamber  116  contact and squeeze the tubing  112 . The rotary member  118  can be driven in any suitable manner. In some configurations, a motor drives the rotary member  118 . In some configurations, a rotary motor drives the rotary member  118 . In some configurations, an electric motor drives the rotary member  118 . 
     In the peristaltic pump  110 , the gases of the recirculation circuit  28  are constrained to contact only the tubing  112 . As such, the peristaltic pump  110  generally can be reused while the tubing  112  is discarded. In some configurations, the chamber  116 , the rotary member  118 , and the tubing  112  can be supplied as a cartridge. Thus, the cartridge can be easily connected and disconnected, which facilitates simplified reuse. In some configurations, only the tubing  112  is discarded and reused. Any other suitable configuration also can be used that isolates the portion of the pump  110  that must be discarded while preserving the majority of the pump  110  for reuse. 
     As discussed above, any suitable type of pump  60  can be used. For example, as shown in  FIG. 7  and  FIG. 8 , the pump  60  can be a radial compressor  130  or the like. The radial compressor  130 , however, has a vanned member  132  that is in direct contact with the fluid passing through the pump  60 . As such, sterilizing the radial compressor  130  might be more difficult or labor intensive and, due to the use of a motor and other mechanical components, disposing of the entire radial compressor  130  might be cost prohibitive. 
     With reference again to  FIGS. 1 and 2 , the filtration portion  40  can comprise a mechanical filter  41 . The filtration portion  40 , and specifically the filter  41  within the filtration portion  40 , is provided to filter dirty gases after they emerge from the body cavity. In some configurations, the filter  41  can be positioned in a cannula that vents to the atmosphere or at an inlet or an outlet of the flow generator portion  42 . In some configurations, the filter  41  can be, for example, but not limited to, HEPA, chemical, electrostatic, or the like, keeping in mind a desire to filter out smoke particles and other debris. In some configurations, the filter  41  can comprise a carbon filter that is paired with the filter  41 . The carbon filter, or another suitable filter, can be used to remove odors, if desired. 
     The mechanical filter  41  can be contained within the housing  48 . Accordingly, in some instances, the humidity encountered within the active filtration unit  12  can shorten the life span of the mechanical filter  41  if sufficient condensation is allowed to occur. In some configurations, at least a portion of the active filtration unit  12  can be heated while at least a portion of the tube  30  or another portion of the active filtration unit  12  can comprise a hydrophilic material, such as a sulfonated tetrafluoroethylene-perfluoro copolymer (e.g., Nafion®, a registered mark of E. I. du Pont de Nemours and Company) or a poly(ether-ester) block copolymer (for example, Sympatex®, a registered mark of Sympatex Technologies GmbH), for example but without limitation (“breathable materials” as used herein). In some such configurations, the breathable materials can be formed in a film state or in a foamed state. Such configurations, however, can allow moisture to be lost to the ambient atmosphere through the tube  30 . In such configurations, the moisture lost can be replaced using the humidifier  16  when the primary flow generator  14  is operating, or by including the humidifier  16  within the recirculation circuit  28  (for example, as shown in  FIG. 1 ). Accordingly, lowered humidity levels may be experienced by the filter  41  while maintaining a desired degree of humidification in the body cavity. 
     Gases leaving the body cavity generally contain a high level of humidity. The humidity can result in condensation upon an unheated filter  41  or unheated tubing  30 . The active filtration unit  12  and/or the recirculation circuit  28  can include a condensate management unit  140 . While it is possible to omit a condensate management unit  140 , use of the condensate management unit  140  can increase the operating time of the system  10 . By positioning the condensate management unit  140  upstream of the filter  41  and/or filtration portion  40 , the condensate management unit  140  can help reduce the likelihood of the condensate causing clogging of the filter  41 . Preferably, the condensate management unit  140 , as illustrated, is positioned along the portion of the recirculation circuit  28  that extends from the body cavity (i.e., the inlet into the recirculation system) to the filtration portion  40 . In some configurations, the condensate management unit  140  can be positioned at, near or adjacent an inlet to the filter  41  or filtration portion  40 . In some configurations, the filter  41  can be positioned at, near or adjacent an outlet of the condensate management unit  140 . The condensate management unit  140  can have any suitable configuration. 
     Tn some configurations, a water trap or other form of condenser can be used. The water trap or condenser can use a less-heated, unheated or cooled material that causes vapour to condense into the water trap or condenser. In some configurations, the material can comprise a metal mesh. The material can form a wall or a portion of a wall of the tube  30 . The material can extend into the lumen of the tube  30 . Any other suitable material and/or configuration also can be used. In some configurations, the flow from the body cavity toward the filtration portion  40  passes through the material of the water trap. The water trap can comprise a removable and/or reusable chamber. In such configurations, the water trap chamber can be removed, emptied, cleaned and reinstalled. In some such configurations, the water trap chamber can be autoclaved or sterilized between subsequent uses. In some configurations, the water trap does not have a removable chamber; instead, the water trap itself can be removed, emptied, cleaned and reinstalled. In some such configurations, the water trap can be autoclaved or sterilized between subsequent uses. 
     In some configurations, a desiccant or an absorbent material can be used to capture condensate. For example but without limitation, the desiccant or absorbent material can be a chemical or foam that has an affinity to water or that is a hygroscopic substance. In some configurations, the desiccant or absorbent material can be silica gel. In some configurations, the desiccant or absorbent material can be a foam or sponge. The desiccant or absorbent material can be used with a water trap or can be used in configurations not having a water trap. In some configurations, the desiccant or absorbent material can be contained within a canister. In some configurations, the desiccant or absorbent material can be positioned internally along at least a portion of the tube  30  located between the inlet into the tube  30  (that is, the inlet end positioned at or within the body cavity) and the filtration portion  40 . In some configurations, the desiccant or absorbent material can be positioned within or near the housing  48  of the filtration portion  40 . In some configurations, the desiccant or absorbent material can be positioned within the housing  48  but upstream of the filter  41 . 
     Any suitable mechanism can be provided to pneumatically isolate the recirculation circuit  28  from the primary flow generator  14  (e.g., the insufflator). With reference again to  FIGS. 1 and 2 , a valve assembly  54  can be used to control and regulate the pressures within the insufflation system  10 . The valve assembly  54  can pneumatically isolate the recirculation circuit  28  from the primary flow generator  14 . The valve assembly  54  can be positioned in various locations suitable for isolating the active filtration unit  12  and the recirculation circuit  28  from the primary flow generator  14 . In the illustrated configuration, the valve assembly  54  can comprise a one-way valve  56  (e.g., a check valve) and an overpressure valve  58  (e.g., a pressure relief valve). In other configurations, the valve assembly  54  can comprise any suitable set of valves. 
     The one-way valve  56  can be used to reduce or eliminate the likelihood of pressure generated by the active filtration unit  12  being sensed at the primary flow generator  14  by being transmitted through the insufflation conduit  26 . In some configurations, the one-way valve  56  can be positioned between the humidifier  16  and the recirculation circuit  28 . In some configurations, the one-way valve  56  can be positioned between the primary flow generator  14  and the humidifier  16 . For example, by positioning the one-way valve  56  between the primary flow generator  14  and the humidifier  16 , the compressible volume between the primary flow generator  14  and the one-way valve  56  can be reduced, which can improve control. 
     When the active filtration unit  12  is operating, the one-way valve  56  is closed, which effectively reduces or eliminates the likelihood of the primary flow generator  14  sensing the pressure inside the peritoneum. Tn many cases, the primary flow generator  14  has an alarm or the like that will sound when a pressure is sensed that exceeds a predetermined pressure or when the pressure spikes. However, when the one-way valve  56  closes, the quick movement of the one-way valve  56  can cause a phenomenon known as fluid hammer. Fluid hammer can cause the primary flow generator  14  to mistakenly sense an overpressure condition, which can result in an alarm even though the pressure inside of the body has not changed in any significant manner. Accordingly, in some configurations, the one-way valve  56  can be paired with the overpressure valve  58 , which can function as a hammer arrestor. The overpressure valve  58  may open if the pressure within the upstream flow path exceeds a desired level. Thus, the one-way valve  56  can isolate the active filtration unit  12  from the primary flow generator  14  while the overpressure valve  58  can protect against undesirable pressures upstream of the one-way valve  56 . In some configurations, the one-way valve  56  and the overpressure valve  58  can be integrated into a single unit that limits backflow toward the primary flow generator  14  while also venting excess pressure when the pressure exceeds a predetermined threshold. 
     In some configurations, a valve can be provided that allows the primary flow generator  14  to vent to the ambient atmosphere and to separate the primary flow generator  14  from the recirculation circuit  28  that includes the active filtration unit  12 . In some configurations, a continuously open fixed throttle valve can be used to dampen pressure spikes instead of the overpressure valve  58 . 
     In some configurations, a pressure dampener  150 , such as that shown in  FIG. 9  can be used Instead of, or in addition to, the valve assembly  54 . The pressure dampener  150  can be positioned along the supply conduit  22  or the insufflation conduit  26 . The pressure dampener  150  can isolate the primary flow generator  14  from the recirculation circuit  28 , which reduces or eliminates the likelihood of the primary flow generator  14  alarming as a result of operation of the active filtration unit  12 . In effect, the pressure dampener  150  releases or absorbs excess pressure. For example, during a pressure spike, the pressure dampener  150  absorbs the pressure spike, which reduces the likelihood of operation of the active filtration unit  12  causing the primary flow generator  14  to alarm. The pressure dampener  150  has an added benefit of not temporarily blinding the primary flow generator  14  from the recirculation circuit  28 . Thus, the pressure dampener  150  enables the primary flow generator  14  to continue monitoring or checking a pressure within the body cavity during use of the active filtration unit  12  and the recirculation circuit  28 . 
     As illustrated in  FIG. 9 , the pressure dampener  150  can comprise a chamber  154 . The chamber  154  can be divided into a first subchamber  154   a  and a second subchamber  154   b  by a bladder  156  or any other suitable dividing structure. The first subchamber  154   a  can be in direct fluid communication with the supply conduit  22 , the insufflation conduit  26 , or the tube  30 . In some configurations, the first subchamber  154   a  is directly connected to the supply conduit  22 . The second subchamber  154   b  can be pressurized using any suitable fluid. For example, in some configurations, the second subchamber  154   b  can be pressurized using compressed air or gas. When a pressure pulse is created within the insufflation system  10 , fluid enters the first subchamber  154   a , displacing the bladder  156 , compressing the gas within the second subchamber  154   b  and absorbing the shock of the pressure pulse. When the pressure pulse subsides, the gas within the second subchamber  154   b  expands and pushes the fluid (e.g., carbon dioxide) back into the connected conduit  22 ,  26 ,  30 , thereby virtually eliminating pressure variation and pulsation. 
     The active filtration unit  12  can be operated in any suitable manner. In some configurations, the active filtration unit  12  can be activated and deactivated manually as desired by the surgeon or other operator. An algorithmic control can be implemented using a suitable controller or the like. The controller can be associated with any component of the insufflation system (for example, the active filtration unit  12 , the primary flow generator  14 , the humidifier  16 ) or the controller can be a separate component from the rest of the components of the insufflation system (for example, have a housing and be separate of and separable from all of the other components that may incorporate controllers or the like, such as the active filtration unit  12 , the primary flow generator  14 , and the humidifier  16 ). In some such configurations, the controller can be integrated into the insufflator or gases source and the active filtration unit  12  can be controlled from the insufflator or gases source. 
     In some configurations, an algorithmic control may comprise a timer. In some configurations, because the smoke contained within the body cavity can be filtered through the system within about 20-30 seconds, the active filtration unit  12  is cycled into an active state for 20-30 second increments. In some configurations, an algorithm that comprises a timer may control how long the active filtration unit  12  is turned off and/or how long the active filtration unit  12  is turned on. In some configurations, the active filtration unit  12  can be attached to a cautery device and triggered by current through the cautery device. In some configurations, the active filtration unit  12  can be designed for constant or semi-constant use during a surgical procedure. 
     The active filtration unit  12  acts to remove smoke and debris while enabling the reuse of the conditioned insufflation gases. The moisture and insufflation gases taken from the patient are retained and, therefore, recirculated back to the patient. Desirably, a generally consistent pressure is maintained within the body cavity during operation of the active filtration unit  12 . In other words, the pressure within the body cavity preferably does not significantly decrease during the procedure (i.e., decrease to a level that causes operation of the insufflator to add pressure). In instances in which the pressure within the body cavity decreases during the procedure, the insufflator or other flow generator can provide additional insufflation gases, which can return the pressure to a desired level within the body cavity. 
     Unless the context clearly requires otherwise, throughout this specification, the words “comprise”, “comprising”, and the like, are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense, that is to say, in the sense of “including, but not limited to”. 
     Although the disclosed apparatus and systems have been described by way of example and with reference to possible embodiments thereof, it is to be understood that modifications or improvements may be made thereto without departing from the scope of the disclosure. The disclosed apparatus and systems may also be said broadly to comprise the parts, elements, and features referred to or indicated in this specification, individually or collectively, in any or all combinations of two or more of said parts, elements, or features. Furthermore, where reference has been made to specific components or integers having known equivalents, then such equivalents are herein incorporated as if individually set forth. 
     Any discussion of the prior art throughout this specification should in no way be considered as an admission that such prior art is widely known or forms part of common general knowledge in the field.