Patent Description:
In the last few decades, therapeutic intervention within a body cavity or lumen has developed rapidly with respect to delivery of energy via radiofrequency ablation. While successful in several arenas, radiofrequency ablation has several major downsides, including incomplete ablation, frequent lack of visualization during catheter insertion, potential for overlap during treatment (with some areas receiving twice as much energy as other areas), charring of tissues and requirements for frequent debridement, frequent requirements for additional doses of energy after debridement, and potential perforation of the body cavity or lumen due to the rigidity of the RF electrodes.

Minimally invasive devices and methods which deliver thermal energy to a desired area or extract energy from a desired area can be used, in a consistent, controlled manner that does not char or inadvertently freeze certain tissues or create excessive risk of unwanted organ or lumen damage, cf. <CIT>, <CIT> and <CIT>.

However, devices which utilize cryoablative fluids such as nitrous require the removal of these spent gases from the body after treatment. These exhaust gases may be collected temporarily within a scavenging system or a container but will require removal eventually. The collected exhaust gases may be vented to atmosphere but may expose the user to the gases.

Accordingly, an efficient exhaust gas removal system or method are desired for effectively removing exhaust gases after a treatment procedure.

So as to address the aforementioned issues, the present invention provides for a cryogenic exhaust removal apparatus as defined by claim <NUM>, wherein preferred embodiments of the invention are laid down in the dependent claims. A treatment assembly for cryoablatively treating tissue, e.g., uterine tissue, may generally comprise expanding a liner conforming it against the tissue walls of the uterus, the liner may be inflated with a gas or liquid. Once the elongate shaft has been introduced through the cervix and into the uterus, the distal opening of the shaft may be positioned distal to the internal os and the liner may be deployed either from within the shaft or from an external sheath. The cooling probe may be introduced into the liner interior. As the cryoablative agent (e.g., cryoablative fluid) is introduced into and distributed throughout the liner interior, the exhaust catheter may also define one or more openings to allow for the cryoablative fluid to vent or exhaust from the interior of the liner.

With the discharged cryoablative fluid in a completely gaseous state, the evacuating exhaust line may be vented to the surrounding environment or optionally coupled to a scavenging system to collect the discharged gas to limit exposure. In one variation, an exhaust collection bag may be supported by a pole and connected to the exhaust line for collecting the exhaust fluids or gases. The evacuating exhaust line may be removably coupled to the collection bag via a tubing connector located near or at a bottom of the collection bag.

Once an ablation treatment has been completed and the resulting exhaust gases captured in the bag, the spent nitrous gas (e.g., nitrous oxide gas) may be vented from the bag and into atmosphere. However, the bag may also be evacuated through the plumbing system of the suite or room in which the bag is located by dissolving the nitrous gas into water which may be drained directly into the sink. In this manner, the nitrous gas may vent directly from the bag and into the sink drain without requiring any venting into atmosphere or exposure to any personnel. The drained mixture of water and nitrous gas may accordingly be removed via the plumbing system while the mixture remains at environmentally acceptable levels.

Generally, the evacuation assembly may comprise an assembly housing through which the fluid lines are enclosed. The assembly housing may be positioned within a sink and may include an inlet tubing coupled to the housing for fluidly coupling to a water faucet. The assembly housing may further include a base integrated with the assembly housing for attachment over or in fluid communication with a drain within the sink basin. With the bag filled with the exhaust nitrous gas, the faucet may be turned on to start the flow of water from the faucet so that the water enters inlet tubing, passes through assembly housing where the water flow may be constricted to reduce the pressure, and continues into drain. The constricted fluid flow creates a low pressure within a suction attachment extending from the housing to create a Venturi effect. This low pressure created within the suction attachment may then suction the exhaust gas from the bag, through exhaust line, and into contact with the water flowing through the housing where the exhaust gas may dissolve into the flowing water for draining directly into the drain.

While the evacuation assembly is described as being attached or attachable to the exhaust bag, the evacuation assembly (or any of the assembly variations herein) may alternatively be fluidly coupled directly to the treatment assembly for drawing the exhaust gas directly from the device during a treatment procedure. Moreover, the evacuation assembly may also be used in any number of other procedures where nitrous exhaust gases are created, such as cardiac ablation procedures, or any other cryogenic procedure and other gases aside from nitrous may also be used with the evacuation assembly as so desired.

The apparatus generally comprises a housing having an inlet for fluidly coupling to a source of water and an outlet for fluidly coupling to a drain, and a suction chamber in fluid communication with the housing, wherein the suction chamber is further configured to be detachably coupled to an exhaust collection reservoir having a volume of exhaust gas. Introduction of water through the inlet generates a pressure reduction within the suction chamber such that the volume of exhaust gas is drawn from the exhaust collection reservoir and into the housing for dissolving into the water and out through the drain.

One variation for evacuating cryogenic exhaust may generally comprise receiving a flow of water through an inlet of a housing, passing the flow of water through the housing such that a pressure within a suction chamber is reduced, drawing a volume of cryogenic exhaust into the suction chamber via the reduced pressure such that the cryogenic exhaust dissolves into the flow of water, and passing the flow of water and dissolved cryogenic exhaust into a drain.

Another variation of the cryogenic exhaust removal system may generally comprise a housing having an inlet for fluidly coupling to a source of water and an outlet for fluidly coupling to a drain, a suction chamber in fluid communication with the housing, wherein the suction chamber is further configured to be detachably coupled to an exhaust collection reservoir having a volume of exhaust gas, wherein introduction of water through the inlet generates a pressure reduction within the suction chamber such that the volume of exhaust gas is drawn from the exhaust collection reservoir and into the housing for dissolving into the water and out through the drain, and an exhaust collection apparatus containing the volume of exhaust gas for fluidly coupling to the suction chamber via an exhaust line.

The cooling probe <NUM> as well as the balloon assembly may be variously configured, for instance, in an integrated treatment assembly <NUM> as shown in the side view of <FIG>. In this variation, the assembly <NUM> may integrate the elongate shaft <NUM> having the liner or balloon <NUM> extending therefrom with the cooling probe <NUM> positioned translatably within the shaft <NUM> and liner <NUM>. A separate translatable sheath <NUM> may be positioned over the elongate shaft <NUM> and both the elongate shaft <NUM> and sheath <NUM> may be attached to a handle assembly <NUM>. The handle assembly <NUM> may further comprise an actuator <NUM> for controlling a translation of the sheath <NUM> for liner <NUM> delivery and deployment.

With the sheath <NUM> positioned over the elongate shaft <NUM> and liner <NUM>, the assembly <NUM> may be advanced through the cervix and into the uterus UT where the sheath <NUM> may be retracted via the handle assembly <NUM> to deploy the liner <NUM>, as shown in <FIG>. As described above, once the liner <NUM> is initially deployed from the sheath <NUM>, it may be expanded by an initial burst of a gas, e.g., air, carbon dioxide, etc., or by the cryoablative fluid. In particular, the tapered portions of the liner <NUM> may be expanded to ensure contact with the uterine cornu. The handle assembly <NUM> may also be used to actuate and control a longitudinal position of the cooling probe <NUM> relative to the elongate shaft <NUM> and liner <NUM> as indicated by the arrows.

In another variation of the treatment assembly, <FIG> shows a perspective view of a cryoablation assembly having a handle assembly <NUM> which may integrate the electronics and pump assembly <NUM> within the handle itself. An exhaust tube <NUM> may also be seen attached to the handle assembly <NUM> for evacuating exhausted or excess cryoablative fluid or gas from the liner <NUM>. Any of the cryoablative fluids or gases described herein may be utilized, e.g., compressed liquid-to-gas phase change of a compressed gas such as nitrous oxide (N<NUM>O), carbon dioxide (CO<NUM>), Argon, etc. The cooling probe <NUM> may be seen extending from sheath <NUM> while surrounded or enclosed by the liner or balloon <NUM>. Hence, the handle assembly <NUM> with coupled cooling probe <NUM> and liner <NUM> may provide for a single device which may provide for pre-treatment puff-up or inflation of the liner <NUM>, active cryoablation treatment, and/or post-treatment thaw cycles.

The handle assembly <NUM> may also optionally incorporate a display for providing any number of indicators and/or alerts to the user. For instance, an LCD display may be provided on the handle assembly <NUM> (or to a separate control unit connected to the handle assembly <NUM>) where the display counts down the treatment time in seconds as the ablation is occurring. The display may also be used to provide measured pressure or temperature readings as well as any number of other indicators, symbols, or text, etc., for alerts, instructions, or other indications. Moreover, the display may be configured to have multiple color-coded outputs, e.g., green, yellow, and red. When the assembly is working through the ideal use case, the LED may be displayed as a solid green color. When the device requires user input (e.g. when paused and needing the user to press the button to re-start treatment) the LED may flash or display yellow. Additionally, when the device has faulted and treatment is stopped, the LED may flash or display a solid red color.

<FIG> shows the handle assembly <NUM> in a perspective exploded view to illustrate some of the components which may be integrated within the handle <NUM>. As shown, the liner <NUM> and sheath <NUM> may be coupled to a sheath bearing assembly <NUM> and slider base block assembly <NUM> for controlling the amount of exposed treatment length along the cooling probe <NUM> (and as described in further detail below). An actuatable sheath control <NUM> may be attached to the slider base block assembly <NUM> for manually controlling the treatment length of the cooling probe <NUM> as well. Along with the electronics and pump assembly <NUM> (which may optionally incorporate a programmable processor or controller in electrical communication with any of the mechanisms within the handle <NUM>), an exhaust valve <NUM> (e.g., actuated via a solenoid) may be coupled to the exhaust line <NUM> for controlling not only the outflow of the exhausted cryoablation fluid or gas but also for creating or increasing a backpressure during treatment, as described in further detail below.

In one example of how the handle assembly <NUM> may provide for treatment, <FIG> illustrate schematic side views of how the components may be integrated and utilized with one another. As described herein, once the sheath <NUM> and/or liner <NUM> has been advanced and initially introduced into the uterus, the liner <NUM> may be expanded or inflated in a pre-treatment puff up to expand the liner <NUM> into contact against the uterine tissue surfaces in preparation for a cryoablation treatment. As illustrated in the side view of <FIG>, a pump <NUM> integrated within the handle assembly <NUM> may be actuated and a valve <NUM> (e.g., actuatable or passive) fluidly coupled to the pump <NUM> may be opened (as indicated schematically by an "O" over both the pump <NUM> and valve <NUM>) such that ambient air may be drawn in through, e.g., an air filter <NUM> integrated along the handle <NUM>, and passed through an air line <NUM> within the handle and to an exhaust block <NUM>. The exhaust block <NUM> and air line <NUM> may be fluidly coupled to the tubular exhaust channel which extends from the handle <NUM> which is further attached to the cooling probe <NUM>. As the air is introduced into the interior of the liner <NUM> (indicated by the arrows), the liner <NUM> may be expanded into contact against the surrounding uterine tissue surface.

A cryoablative fluid line <NUM> also extending into and integrated within the handle assembly24 may be fluidly coupled to an actuatable valve <NUM>, e.g., actuated via a solenoid, which may be manually closed or automatically closed (as indicated schematically by an "X" over the valve <NUM>) by a controller to prevent the introduction of the cryoablative fluid or gas into the liner <NUM> during the pre-treatment liner expansion. An infusion line <NUM> may be fluidly coupled to the valve <NUM> and may also be coupled along the length of the sheath <NUM> and probe <NUM>, as described in further detail below. The exhaust valve <NUM> coupled to the exhaust line <NUM> may also be closed (as indicated schematically by an "X" over the valve <NUM>) manually or automatically by the controller to prevent the escape of the air from the exhaust block <NUM>.

During this initial liner expansion, the liner <NUM> may be expanded in a gradual and controlled manner to minimize any pain which may be experienced by the patient in opening the uterine cavity. Hence, the liner <NUM> may be expanded gradually by metering in small amounts of air. Optionally, the pump <NUM> may be programmed and controlled by a processor or microcontroller to expand the liner <NUM> according to an algorithm (e.g., e.g. ramp-up pressure quickly to <NUM> Hg and then slow-down the ramp-up as the pressure increases to <NUM> Hg) which may be stopped or paused by the user. Moreover, the liner <NUM> may be expanded to a volume which is just sufficient to take up space within the uterine cavity. After the initial increase in pressure, the pressure within the liner <NUM> may be optionally increased in bursts or pulses. Moreover, visualization (e.g., via a hysteroscope or abdominal ultrasound) may be optionally used during the controlled gradual expansion to determine when the uterine cavity is fully open and requires no further pressurization. In yet another variation, the liner <NUM> may be cyclically inflated and deflated to fully expand the liner. The inflations and deflations may be partial or full depending upon the desired expansion.

In yet another alternative variation, the system could also use an amount of air pumped into the liner <NUM> as a mechanism for detecting whether the device is in a false passage of the body rather than the uterine cavity to be treated. The system could use the amount of time that the pump <NUM> is on to track how much air has been pushed into the liner <NUM>. If the pump <NUM> fails to reach certain pressure levels within a predetermined period of time, then the controller may indicate that the device is positioned within a false passage. There could also be a limit to the amount of air allowed to be pushed into the liner <NUM> as a way to detect whether the probe <NUM> has been pushed, e.g., out into the peritoneal cavity. If too much air is pushed into the liner <NUM> (e.g., the volume of air tracked by the controller exceeds a predetermined level) before reaching certain pressures, then the controller may indicate the presence of a leak or that the liner <NUM> is not fully constrained by the uterine cavity. The liner <NUM> may also incorporate a release feature which is configured to rupture if the liner <NUM> is not constrained such that if the system attempts to pump up the liner <NUM> to treatment pressure (e.g., <NUM> mmHg), the release feature will rupture before reaching that pressure.

Once the liner <NUM> has been expanded sufficiently into contact against the uterine tissue surface, the cryoablation treatment may be initiated. As shown in the side view of <FIG>, the air pump <NUM> may be turned off and the valve <NUM> may be closed (as indicated schematically by an "X" over the pump <NUM> and valve <NUM>) to prevent any further infusion of air into the liner <NUM>. With the cryoablative fluid or gas pressurized within the line <NUM>, valve <NUM> may be opened (as indicated schematically by an "O" over the valve <NUM>) to allow for the flow of the cryoablative fluid or gas to flow through the infusion line <NUM> coupled to the valve <NUM>. Infusion line <NUM> may be routed through or along the sheath <NUM> and along the probe <NUM> where it may introduce the cryoablative fluid or gas within the interior of liner <NUM> for infusion against the liner <NUM> contacted against the surrounding tissue surface.

During treatment or afterwards, the exhaust valve <NUM> may also be opened (as indicated schematically by an "O" over the valve <NUM>) to allow for the discharged fluid or gas to exit or be drawn from the liner interior and proximally through the cooling probe <NUM>, such as through the distal tip opening. The fluid or gas may exit from the liner <NUM> due to a pressure differential between the liner interior and the exhaust exit and/or the fluid or gas may be actively drawn out from the liner interior, as described in further detail herein. The spent fluid or gas may then be withdrawn proximally through the probe <NUM> and through the lumen surrounded by the sheath <NUM>, exhaust block <NUM>, and the exhaust tube <NUM> where the spent fluid or gas may be vented. With the treatment fluid or gas thus introduced through infusion line <NUM> within the liner <NUM> and then withdrawn, the cryoablative treatment may be applied uninterrupted.

Once a treatment has been completed, the tissue of the uterine cavity may be permitted to thaw. During this process, the cryoablative fluid delivery is halted through the infusion line <NUM> by closing the valve <NUM> (as indicated schematically by an "X" over the valve <NUM>) while continuing to exhaust for any remaining cryoablative fluid or gas remaining within the liner <NUM> through probe <NUM>, through the lumen surrounded by sheath <NUM>, and exhaust line <NUM>, as shown in <FIG>. Optionally, the pump <NUM> and valve <NUM> may be cycled on and off and the exhaust valve <NUM> may also be cycled on and off to push ambient air into the liner <NUM> to facilitate the thawing of the liner <NUM> to the uterine cavity. Optionally, warmed or room temperature air or fluid (e.g., saline) may also be pumped into the liner <NUM> to further facilitate thawing of the tissue region.

As the spent cryoablative fluid or gas is removed from the liner <NUM>, a drip prevention system may be optionally incorporated into the handle. For instance, a passive system incorporating a vented trap may be integrated into the handle which allows exhaust gas to escape but captures any vented liquid. The exhaust line <NUM> may be elongated to allow for any vented liquid to evaporate or the exhaust line <NUM> may be convoluted to increase the surface area of the exhaust gas tube to promote evaporation.

Alternatively, an active system may be integrated into the handle or coupled to the handle <NUM> where a heat sink may be connected to a temperature sensor and electrical circuit which is controlled by a processor or microcontroller. The heat sink may promote heat transfer and causes any liquid exhaust to evaporate. When the temperature of the heat sink reaches the boiling temperature of, e.g., nitrous oxide (around -<NUM>), the handle may be configured to slow or stop the delivery of the cryoablative fluid or gas to the uterine cavity.

The pre-treatment infusion of air as well as the methods for treatment and thawing may be utilized with any of the liner, probe, or apparatus variations described herein. Moreover, the pre-treatment, treatment, or post-treatment procedures may be utilized altogether in a single procedure or different aspects of such procedures may be used in varying combinations depending upon the desired results.

Additionally and/or optionally, the handle <NUM> may incorporate an orientation sensor to facilitate maintaining the handle <NUM> in a desirable orientation for treatment. One variation may incorporate a ball having a specific weight covering the exhaust line <NUM> such that when the handle <NUM> is held in the desirable upright orientation, the treatment may proceed uninterrupted. However, if the handle <NUM> moved out of its desired orientation, the ball may be configured to roll out of position and trigger a visual and/or auditory alarm to alert the user. In another variation, an electronic gyroscopic sensor may be used to maintain the handle <NUM> in the desired orientation for treatment.

<FIG> show cross-sectional side views of yet another variation of a cooling probe which utilizes a single infusion line in combination with a translatable delivery line. To accommodate various sizes and shapes of uterine cavities, the cooling probe may have a sliding adjustment that may be set, e.g., according to the measured length of the patient's uterine cavity. The adjustment may move along the sheath along the exhaust tube as well as the delivery line within the infusion line. The sheath may constrain the liner <NUM> and also control its deployment within the cavity.

In this variation, an infusion line <NUM> (as described above) may pass from the handle assembly and along or within the sheath and into the interior of liner <NUM>. The infusion line <NUM> may be aligned along the probe <NUM> such that the infusion line <NUM> is parallel with a longitudinal axis of the probe <NUM> and extends towards the distal tip <NUM> of the probe <NUM>. Moreover, the infusion line <NUM> may be positioned along the probe <NUM> such that the line <NUM> remains exposed to the corners of the liner <NUM> which extend towards the cornua. With the infusion line <NUM> positioned accordingly, the length of the line <NUM> within the liner <NUM> may have multiple openings formed along its length which act as delivery ports for the infused cryoablative fluid or gas. A separate translating delivery line <NUM>, e.g., formed of a Nitinol tube defining an infusion lumen therethrough, may be slidably positioned through the length of the infusion line <NUM> such that the delivery line <NUM> may be moved (as indicated by the arrows in <FIG>) relative to the infusion line <NUM> which remains stationary relative to the probe <NUM>.

The openings along the length of the infusion line <NUM> may be positioned such that the openings are exposed to the sides of the interior of the liner <NUM>, e.g., cross-drilled. As the cryoablative fluid or gas is introduced through the delivery line <NUM>, the infused cryoablative fluid or gas <NUM> may pass through the infusion line <NUM> and then out through the openings defined along the infusion line <NUM>. By adjusting the translational position of the delivery line <NUM>, the delivery line <NUM> may also cover a selected number of the openings resulting in a number of open delivery ports <NUM> as well as closed delivery ports <NUM> which are obstructed by the delivery line <NUM> position relative to the infusion line <NUM>, as shown in the top view of <FIG>.

By translating the delivery line <NUM> accordingly, the number of open delivery ports <NUM> and closed delivery ports <NUM> may be adjusted depending on the desired treatment length and further ensures that only desired regions of the uterine tissue are exposed to the infused cryoablative fluid or gas <NUM>. Once the number of open delivery ports <NUM> has been suitably selected, the infused cryoablative fluid or gas <NUM> may bypass the closed delivery ports <NUM> obstructed by the delivery line <NUM> and the fluid or gas may then be forced out through the open delivery ports <NUM> in a transverse direction as indicated by the infusion spray direction <NUM>. The terminal end of the infusion line <NUM> may be obstructed to prevent the distal release of the infused fluid or gas <NUM> from its distal end. Although in other variations, the terminal end of the infusion line <NUM> may be left unobstructed and opened.

<FIG> show top and perspective views of the expanded liner <NUM> with four pairs of the open delivery ports <NUM> exposed in apposed direction. Because the infused fluid or gas <NUM> may be injected into the liner <NUM>, e.g., as a liquid, under relatively high pressure, the injected cryoablative liquid may be sprayed through the open delivery ports <NUM> in a transverse or perpendicular direction relative to the cooling probe <NUM>. The laterally infused cryoablative fluid <NUM> may spray against the interior of the liner <NUM> (which is contacted against the surrounding tissue surface) such that the cryoablative liquid <NUM> coats the interior walls of the liner <NUM> due to turbulent flow causing heavy mixing. As the cryoablative liquid <NUM> coats the liner surface, the sprayed liquid <NUM> may absorb heat from the tissue walls causing rapid cooling of the tissue while also evaporating the liquid cryogen to a gas form that flows out through the cooling probe <NUM>. This rapid cooling and evaporation of the cryoablative liquid <NUM> facilitates the creation of a fast and deep ablation over the tissue. During treatment, the temperature within the cavity typically drops, e.g., -<NUM>° C, within <NUM>-<NUM> seconds after the procedure has started. While the interior walls of the liner <NUM> are first coated with the cryoablative liquid <NUM>, a portion of the cryoablative liquid <NUM> may no longer change phase as the procedure progresses.

While four pairs of the open delivery ports <NUM> are shown, the number of exposed openings may be adjusted to fewer than four pairs or more than four pairs depending on the positioning of the delivery line <NUM> and also the number of openings defined along the infusion line <NUM> as well as the spacing between the openings. Moreover, the positioning of the openings may also be adjusted such that the sprayed liquid <NUM> may spray in alternative directions rather than laterally as shown. Additionally and/or alternatively, additional openings may be defined along other regions of the infusion line <NUM>.

Further variations of the treatment assembly features and methods which may be utilized in combination with any of the features and methods described herein may be found in the following patent applications:.

Yet another variation of the treatment assembly <NUM> is shown in the side and partial cross-sectional side views of <FIG> which illustrate a housing <NUM> having a handle <NUM> and a reservoir housing <NUM> extending from and attached directly to the handle <NUM>. <FIG> further illustrates a perspective assembly view of the treatment assembly <NUM> and some of its components contained internally.

The sheath <NUM> having the liner <NUM> may extend from the housing <NUM> while an actuator <NUM> may be located, for instance, along the handle <NUM> to enable the operator to initiate the cryoablative treatment. A reservoir or canister <NUM> fully containing the cryoablative agent (as described herein) may be inserted and retained within the reservoir housing <NUM>. The reservoir housing <NUM> and/or the handle <NUM> may further incorporate a reservoir engagement control <NUM> which may be actuated, e.g., by rotating the control <NUM> relative to the handle <NUM>, to initially open fluid communication with the reservoir or canister <NUM> to charge the system for treatment.

The reservoir or canister <NUM> may be inserted into the reservoir housing <NUM> and into secure engagement with a reservoir or canister valve <NUM> which may be coupled to the reservoir engagement control <NUM>. The valve <NUM> may be adjusted to open the reservoir or canister <NUM> for treatment or for venting of the discharged cryoablative agent during or after treatment. An inflow modulation control unit <NUM> (e.g., an actuatable solenoid mechanism) may be coupled directly to the reservoir or canister valve <NUM> and the cryoablative fluid line <NUM> may be coupled directly to the modulation control unit <NUM> and through the sheath <NUM> and into fluid communication within the liner <NUM>, as described herein.

During or after treatment, the discharged cryoablative fluid may be evacuated through the exhaust block <NUM> contained within the housing and then through the exhaust line <NUM> coupled to the exhaust block <NUM>. The exhaust line <NUM> may extend through the handle <NUM> and the reservoir housing <NUM> and terminate at an exhaust line opening <NUM> which may be attached to another exhaust collection line.

With the discharged cryoablative agent in a completely gaseous state, the evacuating exhaust line <NUM> may be vented to the surrounding environment or optionally coupled to a scavenging system to collect the discharged gas to limit exposure. <FIG> show assembly views of examples of collection bags which may be optionally used with the treatment assembly. Scavenging systems may incorporate features such as orifices or valves to prevent any vacuum applied by the scavenging unit from interfering with the backpressure within the treatment device.

<FIG> shows an inflating collection bag <NUM> which is expandable in width coupled to the evacuating exhaust line <NUM> via a disconnect valve <NUM> (e.g., unidirectional valve). The collection bag <NUM>, which may be reusable or disposable, may be supported via a pole <NUM> and may also incorporate a release plug <NUM> which may allow for the venting of the collected gas during or after a treatment procedure is completed.

Similarly, <FIG> shows an accordion-type collector <NUM> also supported via a pole <NUM> and a connector <NUM> attached to the collector <NUM>. The evacuating exhaust line <NUM> may be removably coupled to the collector <NUM> via a disconnect valve <NUM> (e.g., unidirectional valve) and may also incorporate a release plug <NUM> for venting any collected gas during or after a treatment procedure. The vertically-expanding collector <NUM> may define a hollow passageway through the center of the vertical bellows which allows for the connector <NUM> (e.g., rigid rod or flexible cord) to pass through and support the base of the collector <NUM>. The connector <NUM> also prevents the collector <NUM> from falling over to a side when inflating. As the gas enters through the bottom of the collector <NUM>, the bellow may inflate upward.

In yet another variation, <FIG> shows an exhaust collection bag <NUM> which may also be supported by the pole <NUM>. The evacuating exhaust line <NUM> may be removably coupled to the collection bag <NUM> via a tubing connector <NUM> located near or at a bottom of the collection bag <NUM>. The bag <NUM> itself may be formed from two layers of a lubricious materials which are attached or welded (e.g., RF dielectric welded) around its periphery along its edges <NUM>. Moreover, the collection bag <NUM> may be configured to form an extension <NUM> which projects from the bag <NUM> and forms an opening <NUM> for passing a hook through or to provide a point for attachment. This opening may be reinforced to support, e.g., <NUM> lbs for at least <NUM> hour. The collection bag <NUM> may be designed to hang, e.g., from an IV pole as shown such that it is maintained off the floor to keep it clean should a user want to reuse it a number of times.

The bag <NUM> may be fabricated from, e.g., a polyurethane film, selected for its lubricity, elasticity, clarity, low cost and ability to be RF dielectric welded. Such polyurethane films may be commercially available from API Corporation (DT <NUM>-FM). The film may have a thickness of, e.g., <NUM> (<NUM> inches). Because the bag <NUM> inflates at relatively low pressures, the lubricity of the layers prevents the layers of film from sticking together and allows the bag to readily inflate. Also, to accommodate potential volume increases associated with increased temperatures, the bag <NUM> material also exhibits elasticity, e.g., film elongation may be on the order of <NUM>%. The bag may be fabricated to have a burst pressure of at least greater than or equal to, e.g., ≥ <NUM> kPa (<NUM> psi). The bag <NUM> may also be fabricated so as to be at least partially transparent so that the clarity of the bag results in an object that visually occupies less space in the procedure room because objects can be seen through it. The bag <NUM> and its variations are described in further detail in <CIT> (<CIT>).

Once an ablation treatment has been completed and the resulting exhaust gases captured in the bag <NUM>, the spent nitrous gas (e.g., nitrous oxide gas) may be vented from the bag <NUM> and into atmosphere. However, the bag <NUM> may also be evacuated through the plumbing system of the suite or room in which the bag <NUM> is located by dissolving the nitrous gas into water which may be drained directly into the sink. In this manner, the nitrous gas may vent directly from the bag <NUM> and into the sink drain without requiring any venting into atmosphere or exposure to any personnel. The drained mixture of water and nitrous gas may accordingly be removed via the plumbing system while the mixture remains at environmentally acceptable levels.

The bag <NUM> and any of its various embodiments and treatment devices may be utilized in any combination with the exhaust evacuation systems disclosed herein.

<FIG> illustrates one example of how the contents of the spent exhaust gas contained within the bag <NUM> may be dissolved directly into water for draining, e.g., into a sink of the room in which the bag <NUM> is located. The evacuating exhaust line <NUM>, as shown in <FIG>, may be decoupled from the treatment assembly <NUM> and attached to an evacuation assembly <NUM> while the line <NUM> remains fluidly coupled to the bag <NUM>. Alternatively, a separate line may be coupled between the bag <NUM> and the evacuation assembly <NUM>.

The evacuation assembly <NUM> may generally comprise an assembly housing <NUM> through which the fluid lines are enclosed. The assembly housing <NUM> may be positioned within a sink <NUM> and may include an inlet tubing <NUM> coupled to the housing <NUM> for fluidly coupling to a water faucet <NUM>. The assembly housing <NUM> may further include a base <NUM> integrated with the assembly housing <NUM> for attachment over or in fluid communication with a drain <NUM> within the sink basin <NUM>. With the bag <NUM> filled with the exhaust nitrous gas, the faucet may be turned on to start the flow of water from the faucet <NUM> so that the water enters inlet tubing <NUM>, passes through assembly housing <NUM> where the water flow may be constricted to reduce the pressure, and continues into drain <NUM>. The constricted fluid flow creates a low pressure within a suction attachment <NUM> extending from the housing <NUM> to create a Venturi effect. This low pressure created within the suction attachment <NUM> may then suction the exhaust gas from the bag <NUM>, through exhaust line <NUM>, and into contact with the water flowing through the housing <NUM> where the exhaust gas may dissolve into the flowing water for draining directly into the drain <NUM>.

While the evacuation assembly <NUM> is described as being attached or attachable to the exhaust bag <NUM>, the evacuation assembly <NUM> (or any of the assembly variations herein) may alternatively be fluidly coupled directly to the treatment assembly <NUM> for drawing the exhaust gas directly from the device during a treatment procedure. Moreover, the evacuation assembly <NUM> may also be used in any number of other procedures where nitrous exhaust gases are created, such as cardiac ablation procedures, or any other cryogenic procedure and other gases aside from nitrous may also be used with the evacuation assembly <NUM> as so desired.

<FIG> schematically illustrates the flow path through the assembly housing <NUM>, which is shown in <FIG> for reference. The flow assembly <NUM> is illustrated with the inlet <NUM>' corresponding to the inlet tubing <NUM>. A contraction section <NUM> may reduce the cross-sectional area of the inlet <NUM>' and continue through a throat section <NUM> which may increase through a diffuser section <NUM> and which continues to an outlet <NUM>' for exiting into the drain <NUM>. The suction chamber <NUM>' may be fluidly coupled to the exhaust line <NUM> for directly drawing the exhaust gas from the bag <NUM> and into the suction chamber <NUM>' where the gas may dissolve directly into the water passing through the flow assembly <NUM>.

In order to create the Venturi effect with the flow assembly <NUM>, the cross-sectional areas of the inlet <NUM>' and outlet <NUM>' as well as the cross-sectional areas of the contraction section <NUM>, throat section <NUM>, and diffuser section <NUM> may be varied depending upon the desired suction rate for draining the exhaust gas.

In one variation, with an inlet water temperature of <NUM>° F (<NUM>° C) and a flow rate of <NUM> litres per minute (<NUM> Gallon Per Min. ) from the faucet <NUM>, a sufficient suction force may be generated by the flow assembly <NUM> to create an exhaust flow rate of <NUM> litres per hour (<NUM> Standard Cubic Feet Per Hour) at standardized conditions of temperature and pressure through the exhaust line <NUM>. For a given volume of the bag <NUM>, the flow assembly <NUM> may completely empty the bag <NUM> of the exhaust gas within <NUM>. A flow rate of <NUM> litres per minute (<NUM> GPM) of water from the faucet <NUM> and through the flow assembly <NUM> may generate an exhaust flow rate of <NUM> litres per hour (<NUM> SCFH) through the exhaust line <NUM> and a flow rate of <NUM>,<NUM> litres per minute (<NUM> GPM) of water through the flow assembly <NUM> may generate an exhaust flow of about <NUM> litres per hour (<NUM> SCFH) through the exhaust line <NUM>. If the temperature of the inlet water were increased to, e.g., <NUM>° F (<NUM>° C), the corresponding exhaust flow rate may be <NUM> (<NUM> SCFH).

In alternative variations of the flow assembly <NUM>, with the inlet water flow rate of <NUM>,<NUM> litres per minute (<NUM> GPM), the exhaust flow rate may be increased to, e.g., <NUM>,<NUM> litres per hour (SCFH). Other variations of the design of the flow assembly <NUM> may be altered to increase or decrease the corresponding exhaust flow rate.

While the temperature of the water may not have a significant effect on the suction force generated to draw the exhaust gas, the water temperature as well as the temperature of the exhaust gas (e.g., nitrous oxide) may have an effect on the solubility of the gas. As the temperature of the water and/or gas decreases, the solubility of the gas increases. Hence, the temperature of the water and/or gas may be potentially altered or varied depending upon the desired solubility and rate of dissolution of the gas into the water flow. For instance, if the exhaust gas dissolves into the water flow at too slow of a rate as the exhaust is drawn into the housing by the suction force, the undissolved gas may build and potentially escape from beneath the base <NUM> or drain <NUM> rather than being dissolved into the water and passing into and through the drain <NUM>.

Accordingly, the suction pressure generated by the Venturi effect may be tuned to combine the water flow and exhaust gas (e.g., nitrous oxide) in the proper solubility ratio to minimize the quantity of water and time needed to dissolve the exhaust gas in the water and empty the exhaust collection bag <NUM>. If the Venturi effect (suction force) is too high, too much nitrous oxide gas may be drawn into the housing <NUM> and remain in gaseous form which could build up pressure beneath the sealing base <NUM> and cause the exhaust gas to escape from the perimeter of the base <NUM>. Conversely, if the Venturi effect (suction force) is too weak, it may take longer a relatively longer period of time to vent the exhaust collection bag <NUM>.

<FIG> show perspective views of the evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. The assembly<NUM> may be coupled to the inlet tubing <NUM> which may be a flexible length of tubing having an attachment or coupling <NUM> for coupling to the faucet <NUM> in a fluid tight seal. The length of inlet tubing <NUM> may be flexible to accommodate the relative positioning of the assembly <NUM> relative to the positioning of the faucet <NUM>. The base <NUM> may incorporate a suctioning mechanism or sealing ring <NUM> which may also include an opening for the fluid outlet. The base <NUM> may also be sufficiently wide enough to be positioned directly over the drain <NUM> at the bottom of the sink basin <NUM> so that a fluid seal around the drain <NUM> may be formed to prevent the leakage or escape of the water and dissolved nitrous gas.

<FIG> illustrate perspective views of another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> attached to a flexible inlet tubing <NUM> having an attachment or coupling <NUM> for coupling to the faucet <NUM> in a fluid tight seal. The suction chamber <NUM> may extend from the housing <NUM> for attachment to the evacuation line <NUM>. The assembly housing <NUM> may further include a fluid outlet <NUM> for positioning directly into the drain <NUM>. An attachment base <NUM> having one or more securement arms <NUM> may extend radially from the housing <NUM> and project distally with corresponding suction attachments <NUM>. When the assembly <NUM> is positioned within the sink <NUM>, the fluid outlet <NUM> may be positioned directly into the drain <NUM> and the attachment base <NUM> may slide down the housing <NUM>, as indicated by the arrows, allowing for the suction attachments <NUM> to attach onto the floor of the sink basin <NUM> to maintain a position of the assembly housing <NUM> during evacuation.

<FIG> illustrate perspective views of yet another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> attached to a flexible inlet tubing <NUM> having an attachment or coupling <NUM> for coupling to the faucet <NUM> in a fluid tight seal. The suction chamber <NUM> may extend from the housing <NUM> for attachment to the evacuation line <NUM>. The assembly housing <NUM> may further include a fluid outlet <NUM> which may attach to a base for positioning directly over the drain <NUM>. The base <NUM> may be attached to a pump <NUM> fluidly coupled via opening <NUM> which may allow for the base <NUM> to be suctioned onto the sink basin <NUM> around the drain <NUM> to create a fluid tight connection. When the assembly <NUM> is positioned within the sink <NUM>, the base <NUM> may be positioned directly over the drain <NUM> and the pump <NUM> may be actuated to secure the base <NUM> onto the floor of the sink basin <NUM> to maintain a position of the assembly housing <NUM> during evacuation.

<FIG> shows a perspective view of the evacuation assembly <NUM> but where the base <NUM> is configured to create a suction force using the low pressure generated by the flow assembly within the housing <NUM> rather than a separate pump. When the water is introduced through the assembly <NUM>, a diverter switch <NUM> may be actuated upon the suction chamber <NUM> to close off the evacuation line <NUM> and instead couple to a second line in fluid communication with a suctioning chamber in base <NUM>. Once the base <NUM> has been sufficiently adhered within the sink, the diverter switch <NUM> may be actuated again to generate the suction within the suction chamber <NUM>. Alternatively, chamber <NUM> may be closed to allow for a second flow assembly within the base <NUM> to generate a suctioning force for adhering the base <NUM>. A switch or actuator <NUM>, as illustrated in the perspective detail view of <FIG>, may be used for this purpose.

In yet other variations, rather than incorporating a diverter switch or actuator, the flow may be diverted automatically into the base until a threshold suction force is reached for securing the base to the sink basin. Once the threshold level has been attained, a valve having a predetermined closing pressure or a separate controller monitoring the pressure may be used to automate the flow.

<FIG> illustrate perspective views of yet another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> having an attachment or coupling <NUM> for directly coupling the housing <NUM> to the faucet <NUM> in a fluid tight seal. The suction chamber <NUM> may extend from the housing <NUM> for attachment to the evacuation line <NUM>. The assembly housing <NUM> may further include a fluid outlet <NUM> which may attach to a base <NUM> having a suction cup around a sealing ring for positioning directly over the drain <NUM>.

<FIG> illustrate perspective views of yet another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> attached to a flexible inlet tubing <NUM> having an attachment or coupling <NUM> for coupling to the faucet <NUM> in a fluid tight seal. The suction chamber may be contained within housing <NUM> for attachment to the evacuation line <NUM>. The housing <NUM> may be contain a reservoir <NUM>, e.g., <NUM>, within for receiving a volume of the water which may function as a weight which prevents the housing <NUM> from moving when positioned over the drain <NUM>. A diverter switch <NUM> may be actuated to initially divert the flow of water into the reservoir <NUM> within the housing <NUM>. Once sufficiently filled, the diverter switch <NUM> may be actuated to allow for the water flow to pass through the fluid assembly within the housing <NUM>. The assembly housing <NUM> may further include a fluid outlet which may be positioned directly over the drain <NUM>.

<FIG> illustrate perspective views of yet another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> having an attachment or coupling <NUM> for coupling the housing <NUM> directly to the faucet <NUM> in a fluid tight seal. With the fluid assembly contained within the housing <NUM>, a flexible outlet tubing <NUM> may be coupled to the housing <NUM> and extend towards a base <NUM> for positioning over the drain <NUM>. The evacuation line <NUM> may be attached directly to a suction chamber contained within the housing <NUM>.

<FIG> shows a perspective view of a similar embodiment where the evacuation assembly <NUM> may have a housing oriented to extend vertically with an attachment or coupling <NUM> which may be coupled to the faucet <NUM> to directly attach the housing <NUM> to the faucet <NUM>. The evacuation line <NUM> may be attached directly to a suction chamber contained within the housing <NUM> and the housing <NUM> may further incorporate a diverter switch <NUM> which may be actuated engage or disengage the flow of water from the faucet <NUM>.

<FIG> illustrate perspective views of yet another variation of an evacuation assembly <NUM> detached from the sink and also attached within the sink <NUM>. In this variation, the evacuation assembly <NUM> may include an assembly housing <NUM> attached to a flexible inlet tubing <NUM> having an attachment or coupling <NUM> for coupling to the faucet <NUM> in a fluid tight seal. The suction chamber <NUM> may extend from the housing <NUM> for attachment to the evacuation line <NUM>. The housing <NUM> may also be attached directly to a base <NUM> or may incorporate a tubing for coupling between the housing <NUM> and the base <NUM> which may be positioned directly over the drain <NUM>. The housing <NUM> may also be oriented in this variation to extend horizontally relative to the sink basin <NUM> to facilitate the diffusion of the exhaust gas from exhaust line <NUM> for dissolving into the water flowing through the housing <NUM>. Alternatively, the housing <NUM> may instead be angled relative to the sink basin <NUM>.

Claim 1:
A cryogenic exhaust removal apparatus, comprising:
an exhaust collection reservoir (<NUM>) having a volume of exhaust gas;
a housing (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) having an inlet for fluidly coupling to a source of water and an outlet for fluidly coupling to a drain (<NUM>), wherein the inlet is configured to be fluidly coupled to a faucet (<NUM>);
a suction chamber (<NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) in fluid communication with the housing (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>), wherein the suction chamber (<NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) is further configured to be detachably coupled to the exhaust collection reservoir (<NUM>) via an exhaust line (<NUM>),
wherein introduction of water through the inlet generates a pressure reduction within the suction chamber (<NUM>, <NUM>', <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) such that the volume of exhaust gas is drawn from the exhaust collection reservoir (<NUM>) and into the housing (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>) for dissolving into the water and out through the drain (<NUM>).