Patent Description:
The present invention relates to a lung access procedure, such as a lung biopsy, and, more particularly, to a system for use in sealing a portion of pleural layers together.

Pneumothorax is a problematic complication of the lung biopsy procedure where air or fluid is allowed to pass into the pleural space as a result of the puncture of the parietal pleura and visceral pleura. Pneumothorax and, more so, pneumothorax requiring chest tube placement, are significant concerns for clinicians performing, and patients undergoing, percutaneous lung biopsies. The incidence of pneumothorax in patients undergoing percutaneous lung biopsy has been reported to be anywhere from <NUM>-<NUM>%, with an average of around <NUM>%. On average, <NUM>% of all percutaneous lung biopsies result in pneumothorax requiring a chest tube to be placed, which results in an average hospital stay of <NUM> days.

Factors that increase the risk of pneumothorax include increased patient age, obstructive lung disease, increased depth of a lesion, multiple pleural passes, increased time that an access needle lies across the pleura, and traversal of a fissure. Pneumothorax may occur during or immediately after the procedure, which is why typically a CT scan of the region is performed following removal of the needle. Other, less common, complications of percutaneous lung biopsy include hemoptysis (coughing up blood), hemothorax (a type of pleural effusion in which blood accumulates in the pleural cavity), infection, and air embolism.

What is needed in the art is a system for use in sealing a portion of pleural layers together.

<CIT> discloses an apparatus for obtaining a lung biopsy with an apparatus capable of sealing tears within the lung and pleural space to reduce the risk of pneumothorax or pulmonary hemorrhage.

The present invention provides a system for use in sealing a portion of pleural layers together and is directed to the system of claim <NUM>. The dependent claims refer to preferred embodiments.

The disclosure is directed to a system for use in sealing a portion of pleural layers together. The system includes an electrical energy source, and an electrocautery probe electrically coupled to the electrical energy source. The electrocautery probe has a cannula shaft portion, a distal penetrating tip, and an intermediate portion interposed between the cannula shaft portion and distal penetrating tip. The electrocautery probe is configured to generate heat. A protein source is coupled to the intermediate portion of the electrocautery probe, wherein the protein source has a protein that is denatured by heat.

The invention according to claim <NUM> is directed to a system for use in sealing a portion of pleural layers together. The system may include a fluid source, an electrical energy source, a grounding pad, and a monopolar electrocautery probe. The fluid source is configured to deliver a sealing fluid, wherein the sealing fluid is heat-activated. The grounding pad is electrically coupled to the electrical energy source. The monopolar electrocautery probe is electrically coupled to the electrical energy source. The monopolar electrocautery probe and grounding pad cooperate to generate heat. The monopolar electrocautery probe has a cannula shaft portion, a distal penetrating tip, and an expandable portion interposed between the cannula shaft portion and distal penetrating tip. The cannula shaft portion has a cannula lumen coupled in fluid communication with the fluid source. The expandable portion is coupled in fluid communication with the fluid source via the cannula lumen. The expandable portion is configured to define a plurality of openings, and is configured such that the sealing fluid that is supplied by the fluid source exits the expandable portion through the plurality of openings to a location external to the monopolar electrocautery probe.

An advantage of the present invention is that the system allows the physician to create an airtight seal of the pleural layers prior to performing a lung procedure, such as a lung biopsy, thereby reducing the risk of pneumothorax during the procedure.

Corresponding reference characters indicate corresponding parts throughout the several views. The exemplifications set out herein illustrate at least one embodiment of the invention, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

Referring now to the drawings, and more particularly to <FIG>, there is shown a schematic diagram of an example of a system <NUM> for sealing a portion of the pleural layers in a lung procedure performed on a patient <NUM>. In the present embodiment, system <NUM> generally includes an electrical energy source <NUM>, a monopolar electrocautery device <NUM>, and a grounding pad <NUM>. Monopolar electrocautery device <NUM> includes a handpiece <NUM> connected to a monopolar electrocautery probe <NUM>.

In the present embodiment, electrical energy source <NUM> may be, for example, an electrosurgical radio frequency (RF) generator. In the present embodiment, electrical energy source <NUM> includes a first RF output <NUM>-<NUM> and a second RF output <NUM>-<NUM>.

First RF output <NUM>-<NUM> of electrical energy source <NUM> is electrically coupled to monopolar electrocautery device <NUM> via a connector cable <NUM>. Connector cable <NUM> may be, for example, a multi-conductor cable that includes electrical conductors that supply control signals from handpiece <NUM> to electrical energy source <NUM> to control a power output of electrical energy source <NUM>, and includes conductors (e.g., a shielded cable, such as an electrical coaxial cable) to supply electrical RF power signals to monopolar electrocautery probe <NUM> of monopolar electrocautery device <NUM>. Accordingly, monopolar electrocautery probe <NUM> is electrically coupled to first RF output <NUM>-<NUM> of electrical energy source <NUM> via connector cable <NUM>.

Second RF output <NUM>-<NUM> of electrical energy source <NUM> is electrically coupled to grounding pad <NUM> via a ground path <NUM>. Grounding pad <NUM> is configured for contact with the patient <NUM>, as is known in the art. It is contemplated that the ground path <NUM> between electrical energy source <NUM> and grounding pad <NUM> may be in the form of a shielded cable, such as an electrical coaxial cable.

Monopolar electrocautery probe <NUM> and grounding pad <NUM> form an RF circuit <NUM>, wherein monopolar electrocautery probe <NUM> serves as a primary electrosurgical electrode and grounding pad <NUM> serves as a return electrode. Monopolar electrocautery probe <NUM> includes a cannula shaft portion <NUM>, a distal penetrating tip <NUM>, and an intermediate portion <NUM> interposed between the cannula shaft portion <NUM> and distal penetrating tip <NUM>.

Monopolar electrocautery probe <NUM> and grounding pad <NUM> cooperate to generate heat when energized with RF energy. More particularly, electrical energy source <NUM> includes circuitry, as is known in the art, for generating an RF output signal having an RF frequency which may be, for example, in a range of <NUM> megahertz (MHz) to <NUM>. The RF output signal generated by electrical energy source <NUM> is delivered to monopolar electrocautery probe <NUM> and grounding pad <NUM>, so as to generate a heating effect at monopolar electrocautery probe <NUM>. Optionally, cannula shaft portion <NUM> of monopolar electrocautery probe <NUM> may include a thermal and electrical insulating exterior layer, e.g., plastic or ceramic, to reduce a transfer of heat from the outer periphery of cannula shaft portion <NUM> to the surrounding tissue.

<FIG> shows a more detailed view of monopolar electrocautery device <NUM>, which may optionally include an introducer cannula <NUM>, which may be installed coaxial with monopolar electrocautery probe <NUM> along a longitudinal axis <NUM>. <FIG> shows a functional block diagram of system <NUM>, including electrical energy source <NUM> and monopolar electrocautery device <NUM> having handpiece <NUM> and monopolar electrocautery probe <NUM>. Introducer cannula <NUM> may be made of a biocompatible metal, such as stainless steel, and may include an insulating layer, e.g., plastic or ceramic, on the inner side wall of the introducer cannula <NUM> to aid in reducing a transfer of heat from the outer periphery of cannula shaft portion <NUM> to introducer cannula <NUM>. Alternatively, introducer cannula <NUM> may be made from non-conductive material, such as plastic or ceramic.

Referring to <FIG> and <FIG>, handpiece <NUM> includes a housing <NUM> that may optionally contain an expander driver <NUM> and a fluid source <NUM>. Handpiece <NUM> includes a button <NUM> for actuating expander driver <NUM> to deploy monopolar electrocautery probe <NUM>, as will be further explained below. Handpiece <NUM> also includes a button <NUM> for actuating fluid source <NUM> for supplying a sealing fluid to monopolar electrocautery probe <NUM>. Handpiece <NUM> further includes a button <NUM> for actuating and controlling the operation of electrical energy source <NUM> in supplying the RF output signal to monopolar electrocautery probe <NUM>.

In the present embodiment, button <NUM> may be in the form of a slider member that is slidable along a slot <NUM>-<NUM> formed in housing <NUM> of handpiece <NUM>. Button <NUM> is connected to expander driver <NUM>. Expander driver <NUM> may include a driver member <NUM>-<NUM>, such as a push rod or cable, which is mechanically connected to each of, and interposed between, button <NUM> and distal penetrating tip <NUM> of monopolar electrocautery probe <NUM>.

Alternatively, expander driver <NUM> may be an electromechanical device, such as a motor or solenoid, having a linearly movable component that is mechanically connected to driver member <NUM>-<NUM>, wherein button <NUM> serves as a switch to electrically actuate the motor or solenoid of expander driver <NUM>.

Button <NUM> is connected to fluid source <NUM> that carries a sealing fluid of a type that is heat-activated. Fluid source <NUM> is coupled in fluid communication with monopolar electrocautery probe <NUM>, and in particular, cannula shaft portion <NUM> has a cannula lumen <NUM>-<NUM> that is coupled in fluid communication with fluid source <NUM>. Stated differently, fluid source <NUM> is configured to deliver the sealing fluid through cannula lumen <NUM>-<NUM> of cannula shaft portion <NUM> to intermediate portion <NUM> of monopolar electrocautery probe <NUM>, wherein the sealing fluid may be heat activated by application of heat supplied by monopolar electrocautery probe <NUM>.

Referring also to <FIG>, in the present embodiment, for example, fluid source <NUM> is a protein source that carries a protein in a fluid form, wherein the protein is denatured and heat-activated by means of heating monopolar electrocautery probe <NUM>. In other words, the protein source accommodates a substance characterized by a protein which is in the non-denatured or non-heat-activated condition. In the present embodiment, fluid source <NUM> may be in the form of a syringe <NUM>-<NUM> having a reservoir <NUM>-<NUM> and a piston <NUM>-<NUM> that slidably resides in reservoir <NUM>-<NUM>. Reservoir <NUM>-<NUM> is configured as a chamber that contains a sealing fluid <NUM> (heat-activated) that contains the protein, and button <NUM> may be a plunger connected to piston <NUM>-<NUM> of syringe <NUM>-<NUM>. A Luer fitting <NUM> is connected to a proximal end <NUM>-<NUM> of cannula shaft portion <NUM>, wherein Luer fitting <NUM> is in fluid communication with cannula lumen <NUM>-<NUM>. Fluid source <NUM>, e.g., syringe <NUM>-<NUM>, includes an output port <NUM>-<NUM> that is connected to Luer fitting <NUM>.

Also, in the present embodiment, sealing fluid <NUM> may be, for example, a solution that contains a protein that is denatured by heat. More particularly, sealing fluid <NUM> may be, for example, a protein-containing solution that includes a protein, e.g., <NUM> to <NUM> % by weight, and optionally may include a crosslinking agent, e.g., <NUM>-<NUM> % by weight. The protein in the solution may be, for example, albumin. In the optional embodiments that include the crosslinking agent, the crosslinking agent in the solution may be, for example, genipin.

As an alternative to providing fluid source <NUM> in the form of a syringe, it is contemplated that piston <NUM>-<NUM> of fluid source <NUM> may be replaced with an electric or pneumatic powered pump, wherein button <NUM> sends an electrical or pneumatic signal to operate the pump to supply sealing fluid <NUM> through cannula lumen <NUM>-<NUM> of cannula shaft portion <NUM> to intermediate portion <NUM> of monopolar electrocautery probe <NUM>.

Referring also to <FIG>, intermediate portion <NUM> of monopolar electrocautery probe <NUM> is configured as an expandable portion <NUM> having a collapsed state <NUM> (<FIG>) and an expanded state <NUM> (<FIG>). In particular, the collapsed state <NUM> of expandable portion <NUM> is defined by an extended position (see <FIG>) of distal penetrating tip <NUM> relative to cannula shaft portion <NUM>, and the expanded state <NUM> of expandable portion <NUM> is defined by a retracted position (see <FIG>) of distal penetrating tip <NUM> relative to cannula shaft portion <NUM>. Referring also to <FIG>, in the present embodiment, a transition of state of expandable portion <NUM> from the collapsed state <NUM> to the expanded state <NUM>, and vice-versa, may be effected by sliding button <NUM> along slot <NUM>-<NUM> of housing <NUM> of handpiece <NUM>. For example, sliding button <NUM> in a proximal direction along slot <NUM>-<NUM> of housing <NUM> pulls driver member <NUM>-<NUM> that is attached to distal penetrating tip <NUM> in the proximal direction, such that the distance between distal penetrating tip <NUM> and cannula shaft portion <NUM> at intermediate portion <NUM> is decreased, thereby expanding expandable portion <NUM>. Optionally, the plurality of expansion members <NUM> of expandable portion <NUM> may be formed from a memory material, such as nitinol, so as to aid in the transition from the collapsed state <NUM> (<FIG>) to the expanded state <NUM> (<FIG>).

It is contemplated that in some embodiments, the use of memory material, e.g., nitinol, for the plurality of expansion members <NUM> of expandable portion <NUM>, in combination with introducer cannula <NUM>, may be used as a substitute to providing expander driver <NUM>, button <NUM>, and driver member <NUM>-<NUM> connected to distal penetrating tip <NUM>. In such an alternative embodiment, introducer cannula <NUM> will be slid distally over expandable portion <NUM> to collapse expandable portion <NUM> to the collapsed state <NUM>, and introducer cannula <NUM> will be slid proximally to expose expandable portion <NUM> such that expandable portion <NUM> expands in a self-expanding manner to the expanded state <NUM>.

Expandable portion <NUM> includes a plurality of expansion members <NUM> at intermediate portion <NUM>. In one embodiment, for example, the plurality of expansion members <NUM> may be formed by a plurality of longitudinal cuts or slots formed around a periphery of a tubular portion of monopolar electrocautery probe <NUM> to define intermediate portion <NUM>. In such a case, intermediate portion <NUM> may be formed from the same material as that of cannula shaft portion <NUM> of monopolar electrocautery probe <NUM>, such as for example, a biocompatible metal, such as stainless steel.

Alternatively, intermediate portion <NUM> may be a separate tubular component having a plurality of longitudinal cuts or slots formed around a periphery of a tubular portion of intermediate portion <NUM>, and wherein intermediate portion <NUM> is inserted between, and attached to each of, cannula shaft portion <NUM> and distal penetrating tip <NUM>. In such a case, intermediate portion <NUM> may be formed from a different material, e.g., a different biocompatible metal, from that of cannula shaft portion <NUM>, such as for example, nitinol.

The plurality of expansion members <NUM> longitudinally extend between cannula shaft portion <NUM> and distal penetrating tip <NUM>. Also, the plurality of expansion members <NUM> form an annular periphery of intermediate portion <NUM> between cannula shaft portion <NUM> and distal penetrating tip <NUM>.

Expandable portion <NUM> at intermediate portion <NUM> is coupled in fluid communication with fluid source <NUM> via cannula lumen <NUM>-<NUM>. Referring to <FIG>, expandable portion <NUM> is configured to define a plurality of openings <NUM>, wherein each individual opening of the plurality of openings <NUM> lies between two adjacent members of the plurality of expansion members <NUM> around the periphery of intermediate portion <NUM>. Stated differently, a respective opening of the plurality of openings <NUM> is located between each pair of adjacent expansion members of the plurality of expansion members <NUM>. Accordingly, sealing fluid <NUM> that is supplied by fluid source <NUM> (see also <FIG>) exits expandable portion <NUM> through the plurality of openings <NUM> to a location, e.g., at the pleural layers, external to the monopolar electrocautery probe <NUM>.

<FIG> shows an example of an expansion member <NUM>-<NUM> that is representative of each of the plurality of expansion members <NUM>, with the remainder of the individual members of the plurality of expansion members <NUM> broken away (removed) for clarity. Each expansion member of the plurality of expansion members <NUM> includes a proximal end <NUM>, a distal end <NUM>, and an articulation joint <NUM>. Proximal end <NUM> is connected to cannula shaft portion <NUM>, and distal end <NUM> is connected to distal penetrating tip <NUM>. Articulation joint <NUM> is located, e.g., half way, between proximal end <NUM> and distal end <NUM>. Articulation joint <NUM> may be formed, for example, as a fold line <NUM> (see <FIG>) in intermediate portion <NUM>.

Referring again also to <FIG>, in the collapsed state <NUM>, the diameter of cannula shaft portion <NUM> and the diameter of expandable portion <NUM> are substantially equal. However, referring to <FIG>, in the expanded state <NUM>, the diameter of expandable portion <NUM> at its largest circumference, i.e., at articulation joint <NUM>, is larger than the diameter of cannula shaft portion <NUM>, e.g., <NUM> to <NUM> times larger.

Referring to <FIG>, as a variation of the previous embodiment, a coating <NUM> that contains a protein may be applied and formed, e.g., layered, over at least one of the intermediate portion <NUM> and the distal penetrating tip <NUM>. Coating <NUM> is configured to be heat-activated, and serves as a protein source that may be a substitute for (not according to the present invention), or supplemental to, fluid source <NUM>. Coating <NUM> may be formed, in whole or in part, from a protein containing material, such as for example, a material containing collagen. Coating <NUM> may serve a primary protein source, or alternatively, may serve as a secondary protein source. As a secondary protein source, the collagen may serve as a secondary protein to the primary protein source, e.g., sealing fluid <NUM>.

While in the present embodiment coating <NUM> is applied over intermediate portion <NUM> having expandable portion <NUM> that includes a plurality of expansion members <NUM>, it is contemplated that, alternatively, the coating <NUM> may be applied to an intermediate portion that does not include expandable portion <NUM>.

Referring to <FIG>, there is depicted a portion of a chest wall <NUM> and lung <NUM> of a patient. Referring again to <FIG>, monopolar electrocautery probe <NUM>, alone or in combination with introducer cannula <NUM>, may be used to form an access opening <NUM> to the interior of lung <NUM>. In particular, access opening <NUM> is formed between adjacent ribs <NUM>-<NUM>, <NUM>-<NUM> in the rib cage of chest wall <NUM>, and extends though the parietal pleura <NUM>, the pleural space <NUM>, and the visceral pleura <NUM> to provide access to the interior of the lung <NUM>. Collectively, parietal pleura <NUM> and visceral pleura <NUM> are referred to herein as the pleural layers <NUM>, <NUM>.

Monopolar electrocautery probe <NUM> is shown positioned in access opening <NUM>, with expandable portion <NUM> of intermediate portion <NUM> located distal to (and adjacent), i.e., below, the visceral pleura <NUM> and in the expanded state <NUM> (see also <FIG>). The location of expandable portion <NUM> of monopolar electrocautery probe <NUM> may be determined and/or confirmed, using an imaging system, such as for example, ultrasound imaging or X-ray imaging. <FIG> shows expandable portion <NUM> in the expanded state <NUM> (<FIG>), so as to aid in compressing the pleural layers <NUM>, <NUM> when monopolar electrocautery probe <NUM> is pulled in a proximal direction, toward the user.

<FIG> and <FIG> depict a flowchart of a method for use in a lung access procedure to aid in preventing pneumothorax. The method will be described, and best understood, with further reference to <FIG>.

At step S100, monopolar electrocautery probe <NUM> is inserted along access opening <NUM>, with expandable portion <NUM> of intermediate portion <NUM> in the collapsed state <NUM> (see also <FIG> and <FIG>), alone or in combination with introducer cannula <NUM>, and through the pleural layers <NUM>, <NUM> of a patient (see also <FIG>), with expandable portion <NUM> of intermediate portion <NUM> positioned distal to visceral pleura <NUM>.

At step S102, expandable portion <NUM> of monopolar electrocautery probe <NUM> is expanded to the expanded state <NUM> (see also <FIG>), e.g., by sliding button <NUM> (see <FIG>).

At step S104, monopolar electrocautery probe <NUM> is moved by the user, i.e., pulled, in a proximal direction so that expandable portion <NUM> of monopolar electrocautery probe <NUM> (in the expanded state <NUM>; see also <FIG>) contacts and pulls visceral pleura <NUM> into firm contact with parietal pleura <NUM>, as depicted in <FIG>.

At step S106, electrical energy source <NUM> is actuated, e.g., by depressing button <NUM> (see <FIG>) to cause a heating of distal penetrating tip <NUM> and expandable portion <NUM> of monopolar electrocautery probe <NUM>.

At step S108, fluid source <NUM> is actuated, e.g., by depressing button <NUM> (see <FIG>) to supply the heat-activated sealing fluid <NUM> (see <FIG>) through the plurality of openings <NUM> of expandable portion <NUM> (see <FIG>) and to the tissue regions surrounding expandable portion <NUM> at step S104, including the pleural layers <NUM>, <NUM> (see <FIG>). At this time, with pleural layers <NUM>, <NUM>, being compressed by the prior proximal movement of expandable portion <NUM>, pleural layers <NUM>, <NUM>, are sealed together around access opening <NUM> by the heat activation of sealing fluid <NUM>.

It is contemplated that steps S106 and S108 may be performed sequentially in the order introduced above, or alternatively, may be performed simultaneously. As a further alternative, it is contemplated the order of performing steps S106 and S <NUM> may be reversed.

At step S110, in embodiments that include introducer cannula <NUM> at step S100, introducer cannula <NUM> may then be advanced distally along access opening <NUM> and through the sealed portion of the pleural layers <NUM>, <NUM>.

At step S112, expandable portion <NUM> of monopolar electrocautery probe <NUM> is collapsed to the collapsed state <NUM> (see also <FIG>), e.g., by sliding button <NUM> (see <FIG>), and monopolar electrocautery probe <NUM> may be withdrawn from access opening <NUM>.

At alternative step S114, in embodiments that do not include introducer cannula <NUM> at step S100, following the withdrawal of monopolar electrocautery probe <NUM> from access opening <NUM>, then introducer cannula <NUM> may be inserted into access opening <NUM> and through the sealed portion of the pleural layers <NUM>, <NUM> to maintain an access path to lung <NUM>.

Following the positioning of introducer cannula <NUM> through the sealed portion of the pleural layers <NUM>, <NUM>, a lung procedure, e.g., a lung biopsy, may be performed through introducer cannula <NUM>.

While the primary embodiment above utilizes monopolar electrocautery probe <NUM>, grounding pad <NUM>, and electrical energy source <NUM> in the form of a radio frequency (RF) generator, it is contemplated that the system may be alternatively (not according to the present invention) be configured to utilize a bipolar electrocautery probe having the structural characteristics as in monopolar electrocautery probe <NUM> to facilitate localized delivery of the heat-activated protein material. Also, it is contemplated that an electrocautery probe may take other forms, such as an electrocautery probe having an electrical heating element (DC or AC), having the structural characteristics as in monopolar electrocautery probe <NUM> to facilitate localized delivery of the heat-activated protein material.

As used herein, the term "substantially", and other words of degree, are relative modifiers intended to indicate permissible variation from the characteristic so modified. Such terms are not intended to be limited to the absolute value of the characteristic which it modifies, but rather possessing more of the physical or functional characteristic than the opposite.

Claim 1:
A system (<NUM>) for use in sealing a portion of pleural layers together, comprising:
a fluid source (<NUM>) configured to deliver a sealing fluid (<NUM>), the sealing fluid being heat-activated;
an electrical energy source (<NUM>);
a grounding pad (<NUM>) electrically coupled to the electrical energy source (<NUM>);
a monopolar electrocautery probe (<NUM>) electrically coupled to the electrical energy source (<NUM>), wherein the monopolar electrocautery probe (<NUM>) and grounding pad (<NUM>) cooperate to generate heat,
the monopolar electrocautery probe (<NUM>) having a cannula shaft portion (<NUM>), a distal penetrating tip (<NUM>), and an expandable portion (<NUM>) interposed between the cannula shaft portion (<NUM>) and distal penetrating tip (<NUM>), the cannula shaft portion (<NUM>) having a cannula lumen (<NUM>-<NUM>) coupled in fluid communication with the fluid source (<NUM>), characterized in that :
the expandable portion (<NUM>) is coupled in fluid communication with the fluid source (<NUM>) via the cannula lumen (<NUM>-<NUM>); and
the expandable portion (<NUM>) is configured to define a plurality of openings (<NUM>), wherein the sealing fluid (<NUM>) that is supplied by the fluid source (<NUM>) exits the expandable portion (<NUM>) through the plurality of openings (<NUM>) to a location external to the monopolar electrocautery probe (<NUM>).