WO2025072386A1 - Surgical drains for fluid removal - Google Patents

Abstract

Described herein are surgical drains including porous structures through which negative pressure may be applied to provide suction within a body region being treated. The porous structure may have a high porosity to provide efficient flow of fluid away from the body region. The porous structure may be positioned at a distal end of a suction tube that directs the fluid out of a patient's body. The porous structure may have a sufficiently high column force to withstand collapse in the axial direction as it is extended into the patient's body. The porous structure may be soft and laterally flexible to provide atraumatic contact with body tissue.

Description

SURGICAL DRAINS FOR FLUID REMOVAL

PRIORITY CLAIM

[0001] This patent application claims priority to U.S. provisional patent application no. 63/585,211, titled “SURGICAL DRAIN WITH SHAPED INSERTION TIP,” filed on September 25, 2023, herein incorporated by reference in its entirety.

INCORPORATION BY REFERENCE

[0002] All publications and patent applications mentioned in this specification are herein incorporated by reference in their entirety to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference.

BACKGROUND

[0003] Surgical drains are implants that allow removal of fluid (blood, pus, etc.) and/or gas from a wound or body cavity. This broadly includes nasogastric tubes, urinary catheters, vascular access ports, ventriculoperitoneal shunts, and negative pressure surgical drains. Negative pressure surgical drains are newer, active surgical drain, that are believed to provide advantages not realized with other types of surgical drains.

[0004] In general, surgical drains can help the healing process by removing inflammatory mediators, bacteria, foreign material, and necrotic tissue. Drains can relieve pressure that can impair perfusion or cause pain, thereby decreasing morbidity and reducing inflammation; they enable monitoring for potential complications by allowing easy sampling of fluid during healing; and they can be used to address complications associated with dead space. Active drains use intermittent or continuous negative pressure to pull fluid or gas from a wound or body cavity. Typically, passive drains are open systems, and active drains are closed systems because they rely on negative pressure that is created by the drain.

[0005] Unfortunately, it is often difficult for negative pressure drains to provide uniform negative pressure within tissue cavities (both natural and those formed due to trauma), as soft tissue may collapse onto itself around the location(s) where pressure is applied, sealing off other regions from the pressure source. In addition, it may be difficult to remove the drain from tissue, particularly damaged and healing tissue, without causing further damage and disrupting nascent healing.

[0006] Negative pressure drains may be particularly helpful in treating postpartum uterine bleeding. Postpartum uterine bleeding can occur when the uterine muscles are unable to achieve adequate contraction after delivery to cut off the blood flow that formerly circulated in the utero-placental space. The condition for this lack of contraction is called atony (lack of tone). The uterine muscles typically cuts off the blood flow by contraction of the muscles to effectively pinch the arterial vessels that run through the tissue. In some cases, atony can result in arterial vessels that continue to bleed into the uterus (i.e., postpartum uterine bleeding). Postpartum hemorrhage, or excessive uterine blood loss after birth, is the leading cause of maternal death in the world. Inability to control postpartum bleeding can require a woman to receive multiple blood transfusions, and in severe cases, a full hysterectomy.

Accordingly, it is desirable to control such postpartum bleeding. Current medical devices and surgical procedures have proven inadequate in reducing postpartum hemorrhage or the amount of blood lost, and/or are extremely invasive.

[0007] What is needed are simple to use negative pressure drains that can generate and sustain uniform regions of negative pressure within soft tissue, including, but not limited to the uterus, wounds and body cavities, without disrupting the apposition of tissue within the soft tissue and associated healing.

SUMMARY OF THE DISCLOSURE

[0008] The surgical drains and methods described herein provide negative pressure drains that can generate and sustain uniform regions of negative pressure within soft tissue. These apparatuses (devices, systems, drains, etc.) may include one or more elongate shafts (e.g., tube, catheter) coupled to a porous structure (e.g., mesh or open cell foam). The apparatus may be configured to apply suction through the elongate shaft(s) and the porous structure. The porous structure may be compliant and may distribute the negative pressure (suction) within the soft tissue region being treated.

[0009] The porous structure may be rigid enough to maintain a shape so that fluid and other material may flow into the pores of the porous structure. The porous structure and/or the elongate shaft may have some lateral flexibility to reduce damage to tissue when in contact with the tissue during insertion and retraction of the porous structure and/or the elongate shaft from the body region.

[0010] The surgical drains may be configured to provide highly efficient fluid removal. For example, a surgical drain apparatus may include: an elongate shaft having a lumen extending therethrough; and a porous structure extending from a distal end of the elongate shaft, wherein the porous structure defines a plurality of pores that are arranged to provide a fluid pathway from an outer surface of the porous structure to the lumen of the elongate shaft, wherein the porous structure is sufficiently flexible to bend laterally upon positioning of the porous structure within a body cavity, and wherein the outer surface of the porous structure has a pore area that is at least ten times a cross section area of the lumen of the elongate shaft. In some examples, the length of the porous structure may range from, e.g., about 6 cm to about 20 cm (e.g., about 7 cm to 18 cm, about 8 cm to about 17 cm, etc.). The porous structures may have a porosity ranging from 60% to 85%. The porous structure may be coupled to a distal end of a rod that is configured to move axially within the suction lumen of the elongate shaft, wherein moving the rod distally with respect to the elongate shaft may cause the porous structure to extend out of the distal end of the elongate shaft. The porous structure may include one or both of a mesh and a foam. The plurality of pores may include one or more of a plurality of holes, a plurality of slots, or a plurality of slits. The porous structure may include one or both of a textile material and a non -textile material. The porous structure may be an invertible rolling tube. The surgical drain apparatus may further include a plug on an outer surface of the elongate shaft that is configured to provide a seal with surrounding tissue. The plug may be made of a compressible and self-expanding material. [0011] The combination of the porous structure (e.g. having a pore area that is at least two times a cross section area of the lumen of the elongate shaft), so that the porous structures has a porosity ranging from 60% to 85%, with the ratio of the axial length of the porous structure to the cross section of the lumen of the elongate shaft ranges (e.g., from about 2 to about 100, and more particularly from about 5 to about 100, or from about 10 to about 100 or more, e.g., more than 5, more than 10, more than 15, more than 20, etc.) may result in surprisingly more effective draining without clogging, while maintaining the ability to insert into the post-partum uterus, including after c-section.

[0012] Described herein are methods for draining a body region, such as a wound or a postpartum uterus. For example, a method of draining a body region may include: positioning a porous structure into the body region, wherein the porous structure extends distally from a lumen of an elongate shaft, wherein the outer surface of the porous structure has a pore area that is at least ten times a cross section area of the lumen of the elongate shaft, and further wherein the porous structure is sufficiently flexible to bend laterally upon positioning of the porous structure within the body region; creating a seal around the elongate shaft to maintain a vacuum within the body region; and applying negative pressure through the lumen so that a plurality of flow paths are created through from an outer surface of the porous structure to the lumen of the elongate shaft. A first end of the porous structure may be coupled to the elongate shaft and a second end of the porous structure may be coupled to a rod that is configured to slide within the lumen of the elongate shaft, wherein positioning the porous structure into the body region comprises moving the rod distally within the lumen of the elongate shaft until the porous structure extends distally from the lumen. The porous structure may be a tubular porous structure, wherein positioning the porous structure into the body region comprises causing the tubular porous structure to at least partially invert. An outer surface of the elongate shaft may include a plug, wherein creating the seal comprises expanding the plug to form the seal with surrounding tissue. The plug may be radially compressed when positioned within the surrounding tissue, wherein the plug self-expands to contact the surrounding tissue.

[0013] As described herein, the drain apparatus may be configured to provide bidirectional fluid flow through foam thickness and down a length of the drain apparatus toward the lower pressure vacuum source.

[0014] In some examples, the porous structure may include two or more layers through which suction may be applied to provide multiple flow paths along the length of the porous structure, e.g., into and between the two or more porous layers. When positioned within a soft tissue region (e.g., body cavity) with an applied negative pressure, the porous structure may conform to the tissue as it is drawn together while still maintaining a shape to allow fluid to flow through pores of the porous structure, along the length of the porous structure (e.g., between the layers) and to drain fluid from the soft tissue region. The apparatus may include one or more integrated or separate seals (e.g., plugs) that may help seal off the soft tissue region so that the negative pressure may be sustained.

[0015] These apparatuses may be used for any appropriate tissue, particularly soft tissue injuries in which draining and appropriate alignment of the tissue is desirable, or where negative pressure is desirable. In particular, these apparatuses and methods of using them may be useful for contracting a uterus to reduce hemorrhaging following childbirth.

[0016] The apparatuses may be configured for draining a relatively large areas. For example, the porous structure may have a diameter in a relaxed state of greater than 2 cm (e.g., 2 cm or greater, 3 cm or greater, 4 cm or greater, 5 cm or greater, 6 cm or greater, 7 cm or greater, 8 cm or greater, 9 cm or greater, 10 cm or greater, etc.).

[0017] For example, described herein are surgical drain apparatus comprising: an elongate shaft having a suction lumen extending therethrough; a porous structure extending distally from a distal end region of the elongate shaft, wherein the porous structure comprises two or more adjacent layers of mesh surrounding a central lumen that is in fluid communication with the suction lumen; and a compressible and self-expanding plug assembly on an outer surface of the elongate shaft.

[0018] Any of the apparatuses may include one elongate shafts or multiple elongate shafts (e.g., 2, 3, 4, 5 or more elongate shafts). In some cases, the elongate shafts may be nested (e.g., concentrically arranged) and be translatable (e.g., slidable) with respect to each other. For example, the porous structure and/or the plug may be coupled to a first (e.g., inner) elongate shaft, which may be slidably arranged within a lumen of a second (e.g., outer) elongate shaft. The first elongate shaft may be pushed distally relative to the second elongate shaft (or the second elongate shaft may be pulled proximally relative to the first elongate shaft) to advance and/or expand the porous structure and/or the plug. Likewise, the first elongate shaft may be pulled proximally relative to the second elongate shaft (or the second elongate shaft may be pushed distally relative to the first elongate shaft) to retract and/or collapse the porous structure and/or the plug. Such pulling and pushing may be actuated by manually gripping the first and/or second elongate shafts and sliding them relative to each other, or may be actuated by one or more actuators on a handle of the apparatus.

[0019] In some examples, the elongate shaft includes a flexible and/or curved tube. For example, the elongate shaft may have a polymeric shaft that can be bent or curved to allow it to navigate bends within the anatomy. In some examples the elongate shaft is pre-curved or pre-bent at one or more regions along its length. In some examples, the elongate shaft is steerable over all or a portion of its length. For example the elongate shaft may include one or more tendons to allow steering. The elongate shaft may be any appropriate length. For example, the elongate shaft may be between about 10 and 100 cm (e.g., between about 15 and 80 cm, between about 20 and about 50 cm, etc.). The elongate shaft may be formed of a polymeric material and/or a metallic material.

[0020] Any of the porous structures described herein may include a mesh that is a knitted, woven, or braided material. In some examples, the porous structure is a non-woven material (e.g., such as a sheet or layer of polymeric material through which pores of sufficient size to allow passage of fluids and biological debris (e.g., pus, coagulate, etc.) to pass without significant resistance. In some examples the porous structure is a fabric. The porous structure may be formed of a number of filaments (e.g., strands) of material, such as monofilaments or multiple filaments. For example, the porous structure may include a braided polymeric monofilament having 24 or more strands (e.g., 30 or more strands, 34 or more strands, 36 or more strands, 38 or more strands, 40 or more strands, 42 or more strands, etc.).

[0021] In some examples, the porous structure has a tubular shape, and the apparatus is configured to invert the tubular porous structure. One end of the invertible tubular porous structure may be connected to a first elongate shaft (e.g., tube) and the opposing end of the invertible tubular porous may be connected to a second elongate shaft (e.g., inner tube or rod). The second elongate shaft may be sized and shaped to slide/move axially within the lumen of the first elongate shaft. The invertible tubular porous structure may be extended out of the lumen of the first elongate shape and within the body region by pushing the second elongate shaft.

[0022] In some examples, the second elongate shaft may be formed as a solid member (e.g., a bar, rod, wire, etc.) or it may be hollow (e.g., a catheter, tube, etc.). The second elongate shaft may be a polymeric material and/or a metallic material, such as stainless steel, nitinol, etc. The second elongate shaft may be flexible and/or bent (e.g. pre-bent or precurved) along all or a portion of its length. The second elongate shaft typically has a smaller outer diameter (OD) than the inner diameter (ID) of the first elongate shaft, as the second elongate shaft is slidably disposed within the first elongate shaft. The movement of the second elongate shaft within the first elongate shaft may be limited, and/or may include one or more (e.g. a plurality) of “stop” positions that may releasably hold the relative position of the second elongate shaft and the first elongate shaft. For example, the stop may be configured to hold the position of the second elongate shaft such that the second elongate shaft remains fully withdrawn within the first elongate shaft and an invertible tubular porous structure has a double-walled configuration.

[0023] Any of the apparatuses may include one or more expandable/contractible plugs that may be integrated with the other portions of the apparatus (e.g., the elongate shaft), or may be separate from the other portions of the apparatus and configured to engage with the other portions of the apparatus. The plug may form a seal between apparatus and the walls of a body region (e.g., a canal, channel or incision) so that the porous structure may be sealed within a body cavity being treated and so that negative pressure may be applied to drain the body cavity and/or to collapse the body cavity. The plug may be radially expandable and collapsible so that it may be inserted within the body region in a collapsed state and expanded within the body region to occlude and seal off the access to the body cavity. In some examples, the plug may include a compressible porous material covered by a membrane or sheath (e.g., compliant layer) that may assist in creating the seal against the body tissue. In some examples, the occlude may include one or more balloons. The plug may have a channel or lumen that permits operation of the other components of the apparatus through the plug, without disrupting the seal. In some examples, the plug may surround an external portion of the elongate shaft such that suction can be applied through a lumen of the elongate shaft.

[0024] In some examples, the apparatus may be configured to operate passively. For example, the porous structure and/or the plug may be configured to passively expand when placed within a body region and passively collapse when being removed from a body region (e.g., without activation). In other examples, the porous structure and/or the plug may be expanded and/or collapsed by activation of one or more actuators. The actuator(s) may be on a region of the apparatus that is outside of the body cavity, such as one or more handles of the apparatus. The actuator(s) may be actuated by sliding, pulling, pushing and/or applying pressure (e.g., by a user’s hand).

[0025] The porous structure typically has pores that may be sufficiently large to allow fluids and some solid biological debris (e.g., clots, pus, coagulate) to pass easily. For example, the pores may have a pore diameter that is 0.1 mm or greater (0.2 mm or greater, 0.3 mm or greater, 0.4 mm or greater, 0.5 mm or greater, 0.6 mm or greater, 0.7 mm or greater, 0.8 mm or greater, 0.9 mm or greater 1mm or greater, 1.1 mm or greater, 1.2 mm or greater, 1.3 mm or greater, 1.4 m or greater, etc.). The pores may be formed by the spaces between the strands, e.g., in woven, braided and/or knitted porous meshes. Any of the porous structure may be self-expanding (e.g., formed of a material such as Nitinol, nitinol mixed with polymers, etc.).

[0026] Any of these apparatuses may be coated with one or more materials to enhance their biological efficacy. For example, these apparatuses may be coated with a clot-promoting material, such as aprotinin, tranexamic acid (TXA), epsilon-aminocaproic acid and aminomethylbenzoic acid. For example, any of the porous structures described herein may include a clot-promoting material.

[0027] Any of the apparatuses may include one or more seals between the first elongate shaft and the second elongate shaft. The seals may be configured (e.g., shaped, positioned, formed of an appropriate material, etc.) to allow the second elongate shaft to slide within the lumen of the first elongate shaft, without requiring much force to slide. For example, the seals may be O-rings (or multiple O-rings), which may be lubricated or unlubricated.

[0028] Also described herein are methods of removing material (e.g., fluid) from a body region and/or contracting a body region using any of the apparatuses described herein. These methods may be methods of draining the body region and/or contracting the body region. These methods may be method of reducing hemorrhaging. Any appropriate body region may be treated as described. For example, the body region may be a uterus, and the method may be a method of contracting a uterus to reduce hemorrhaging. The body region may be a wound, and the method may be a method of enhancing healing by draining the wound and/or reducing hemorrhaging and/or enhancing healing. For example, these methods and apparatuses may be used following a breast surgery, treating (e.g., draining) a chest wound, a hernia, etc.

[0029] As mentioned, the porous structure may help distribute the force of the negative pressure. During the application of negative pressure (or in some cases, after a desired amount of negative pressure has been applied), the porous structure may be withdrawn, while leaving the apparatus, including (in some examples) the plug maintaining the negative pressure in place.

[0030] The negative pressure within the body region may be maintained for any appropriate length of time for treatment. For example, the negative pressure may be maintained for 1 minute or longer (e.g., 2 minutes or longer, 5 minutes or longer, 10 minutes or longer, 15 minutes or longer, 20 minutes or longer, 25 minutes or longer, 30 minutes or longer, 45 minutes or longer, 1 hour or longer 1.5 hours or longer, 2 hours or longer, 3 hours or longer, 4 hours or longer, 5 hours or longer, 6 hours or longer, 7 hours or longer, 8 hours or longer, etc.).

[0031] In any of these methods, the distal end of the porous structures may be positioned within the tissue to be treated, such as, e.g., within the uterus.

[0032] All of the methods and apparatuses described herein, in any combination, are herein contemplated and can be used to achieve the benefits as described herein.

BRIEF DESCRIPTION OF THE DRAWINGS

[0033] A better understanding of the features and advantages of the methods and apparatuses described herein will be obtained by reference to the following detailed description that sets forth illustrative embodiments, and the accompanying drawings of which:

[0034] FIGS. 1A-1E illustrate an example of a surgical drain apparatus and an example use of the apparatus: FIG. 1 A shows a side view of the apparatus; FIG. IB shows a section top view of a body region; FIG. 1C illustrates the same body region from a section side view; FIG. ID shows a porous structure of the apparatus inserted into the body region; and FIG. IE shows the apparatus from the same view through the body region as FIG. 1C, showing contraction of the body region.

[0035] FIGS. 2A-2G illustrate side views of example apparatuses having different tubular porous structure structures when in extended and/or expanded states.

[0036] FIGS. 3A-3E illustrate end views and side views of example drain apparatuses with non-rolling porous structures, where at least a portion of the porous structure is covered with a cover that may act as a barrier (or partial barrier) to reduce fluid flow rate.

[0037] FIGS. 4A-4E illustrate end views and side views of example drain apparatuses having porous structures (e.g., textile or foam) of different shapes.

[0038] FIGS. 5 A and 5B illustrate end views and side views of an example rolling drain apparatus. [0039] FIG. 6 illustrates an example rolling drain apparatus having an optional plug positioned around the outside of the tube.

[0040] FIGS. 7A and 7B illustrate an example of a spiral rolling drain apparatus.

[0041] FIGS. 8A-8C illustrate an example of a drain apparatus having a large expandable porous structure.

[0042] FIGS. 9A-9C illustrate an example use of a drain apparatus for treating a body region.

[0043] FIGS. 10A1-10A4 illustrate an example of how a drain apparatus with a tubular porous structure may provide fluid paths for drawing fluid and/or other materials.

[0044] FIGS. 11 A- 11 J illustrate examples of surgical drains with different textile porous structures.

[0045] FIGS. 12A-12F illustrate examples of surgical drains with different non-textile porous structures.

[0046] FIGS. 13A-18C illustrate examples of porous structures in the form of porous tubes.

DETAILED DESCRIPTION

[0047] Described herein are methods and apparatuses (systems and devices) for efficiently draining a region of a body to remove fluid or material from the region and/or contracting the region. This treatment may prevent or reduce bleeding and/or may otherwise enhance healing. These apparatuses and methods, including methods of using them, may be particularly useful for forming regions of uniform negative pressure within a cavity surrounded by soft tissue, and sustaining the negative pressure while atraumatically removing the apparatus from the cavity. The apparatuses may be designed to be simple to use.

[0048] The apparatuses may include a porous structure extending from a lumen of an elongate shaft (e.g., tube). Suction may be applied through the lumen of the elongate shaft and the porous structure to pull fluid (e.g., blood, lymph, etc.) and other material (e.g., blood clots, tissue) proximally away from the body region. The porous structure may include a woven and/or a non-woven material, such as a mesh, an open cell foam and/or a slotted tube. The porous structure may be characterized as having a specified pore area for efficient drainage of fluid and/or other body material from a body region. The porous structure may be configured to reduce the occurrence of clogging, for example, by blood clots and/or other material during drainage.

[0049] The apparatuses may be used to remove inflammatory mediators, bacteria, foreign material, and/or necrotic tissue from a body region, thereby promoting healing of soft tissue. Alternatively or additionally, the negative pressure may cause tissue walls surrounding a body cavity to at least partially contract, which may reduce hemorrhaging. In some examples, the apparatuses may be used to treat a postpartum hemorrhage.

[0050] In some examples, the apparatus may be configured to apply a negative pressure that is within a predetermined range. For example, in the case of treatment for postpartum hemorrhaging, it may be desirable to have sufficiently high negative pressure to collapse uterus quickly so that the body can begin a healing response. However, too high of negative pressure may cause the tissue to compress and reduce perfusion of blood to the tissue. Too high of negative pressure may also cause the patient to experience pain. The pressure range may vary from patient to patient, for example, depending on the patient’s condition and/or preexisting conditions. In some examples, the drain apparatus may be configured to apply a negative pressure ranging from about 10 millimeters of mercury (mmHg) to about 100 mmHg, about 200 mmHg to about 400 mmHg, or up to 760 mmHg. In some cases, particularly for use within the uterus, the negative pressure may be applied between about 70- 90 mmHg.

[0051] The draining efficiency of the apparatuses may depend at least in part on the porosity of the porous structure. In general, porosity is a measure of the void (i.e., empty) space in a material. A material having a 0% porosity is impermeable, and a material having 100 % porosity is infinitely permeable. In some examples, the porous structures described herein may have a porosity ranging from 60% to 85%. Porous structures having greater open area (i.e., pores) per structure surface area may provide superior performance. The porous structure may be in the form of a tube, sheet, sack and/or bag with pores. The pores may have any of a number of shapes and sizes (e.g., round, slotted, or square).

[0052] The porous structure may be characterized as being rigid in some respects and flexible/compliant in other respects. For example, the porous structure may be configured to provide sufficient compression resistance to withstand full collapse of the pores as the negative pressure is applied. That is, the porous structure may maintain some amount of porosity even when compressed during use. The porous structure may also have a sufficiently high column force to withstand collapse of the porous structure in the axial direction as it is extended into the patient’s body and/or through the elongate shaft (tube). However, the porous structure may be soft and laterally flexible enough to reduce the risk of injury to body tissue as it contacts soft tissue and moves within the patient’s body. In some examples, the porous structure is configured to contact soft tissue of the lungs, chest tube, uterus, vagina, breast, a traumatized tissue region, and/or an ulceration. [0053] The porous structure may be configured to distribute the negative pressure more effectively than existing surgical drains. The porous structure may have numerous interconnected pores distributed throughout the porous structure, which act as a network of channels for drawing fluid and/or air from the body cavity (e.g., uterus).

[0054] The porous structure may have a high porosity for efficient fluid flow. In some examples, an outer surface of the porous structure has a pore area that is at least two times (e.g., four times, 5 times, 10 times, etc.) a cross section area of the suction lumen of the elongate shaft. In some examples, a ratio of an axial length of the porous structure to the cross section of the suction lumen of the elongate shaft ranges from about 2-fold to about 100-fold the fabric surface area to the saft cross-sectional area (e.g., between 2-fold and 80- fold, between 2-fold and 75-fold, between 2-fold and 50-fold, between 2-fold and 30-fold, etc.).

[0055] In some examples, the porous structure may have a tubular shape. In some cases, the tubular-shaped porous structure is configured to invert and roll over itself to when deployed and/or retracted into the elongate shaft. Such configuration may be referred to as a “rolling” porous structure.

[0056] Any of these apparatuses described herein may include a plug assembly (“plug”) or closure that may allow the treated region to retain the negative pressure within the body region. For example, the apparatus may include one or more plugs or plug regions that are configured to contact and may be configured to expand against (e.g., may be compressible and expandable), and provide a seal with, surrounding soft tissue, for example, in a channel that leads to a body cavity being treated. In some cases, the plug may be a radially expandable and collapsible feature that is arranged along the elongate shaft proximal to the porous structure. The plug assembly may provide a plugging force (e.g., sealing force) against the tissue of the channel. Once the negative pressure is applied and maintained for a sufficient treatment time, the porous structure and the plugs may be collapsed and/or retracted for gentle removal from the body region. In some examples the plug or plug region(s) may be deconstructed to collapse. In some examples the plug or plug region may include a foam material (e.g., a viscoelastic polyurethane foam, or low-resistance polyurethane foam) that may be compressed and may self-expand to fill and plug the body channel, canal, etc. to maintain the vacuum distal to the plug. In some examples the plug assembly may be disassembled and removed.

[0057] In any of the examples described herein, the porous structure may be pushed, or otherwise advanced and/or positioned, into the region of the body to be drained, so that once positioned it may remove fluid from the body region. Any tissue of the body may be treated with the surgical drains described herein. In particular, soft tissue regions, such as a pocket, chamber, opening, etc. formed or naturally present in tissue. The soft tissue to be treated may be a surgically formed or traumatically formed region of the body, such as a tunneling wound, dead space, seroma forming pocket (surgical wound), etc. For example, the soft tissue to be treated may be a cavity formed by removal of a tumor or other tissue. In some examples, the soft tissue to be treated may be a natural orifice space (bladder, intestine, stomach, uterus, chest cavity, lungs, blood vessel, etc.) or the like. For example, the soft tissue to be treated may be a uterus.

[0058] FIGS. 1A-1E show an example of a surgical drain apparatus 100 and an example use of the apparatus in a soft tissue region of a body. FIG. 1 A shows a side view of the apparatus 100, which includes an elongate shaft 102 (e.g., first elongate shaft) and a distal porous structure 106 coupled to a distal region of the elongate shaft 102. In this example, the elongate shaft 102 is a tube (e.g., a polymeric tube) that includes a lumen. The lumen of the elongate shaft 102 may be in fluid communication with the porous structure 106. For example, a distal end of the lumen may be in fluidic communication with the porous network of the porous structure 106. In some cases, a distal end region of the elongate shaft 102 may include one or more openings that provide fluidic access to the porous network of the porous structure 106. The elongate shaft 102 may be any appropriate length so that it may be manipulated and position the porous structure 106 within the body region being treated. For example, the elongate shaft 102 may be between 5 cm and 100 cm long (e.g., between 10 cm and 50 cm, between 10 cm and 35 cm, etc.). The elongate shaft 102 may be straight (as shown) or curved, including curved with a fixed curve (e.g., between 10-80 degrees). In some cases, the elongate shaft 102 may be laterally flexible. In some cases, the elongate shaft 102 extends distally at least partially within the porous structure 106. In other cases, the elongate shaft 102 does not extend distally within the porous structure 106.

[0059] In some examples, the porous structure 106 is also coupled to an optional second elongate shaft 103 (e.g., rod). For example, one end of the porous structure 106 may be coupled to a distal end of the elongate shaft 102 (e.g., first elongate shaft), and a second end of the porous structure 106 may be coupled to a distal end of the second elongate shaft 103. The second elongate shaft 103 may be slidable within the elongate shaft 102 such that pushing the second elongate shaft 103 distally may cause the porous structure 106 to extend out of the elongate shaft 102. Likewise, pulling the second elongate shaft 103 proximally may cause the porous structure 106 to retract into the elongate shaft 102. [0060] In some examples, the porous structure 106 has a tubular shape, in that it can form an inner lumen. In some cases, a tubular shaped porous structure 106 may invertible back and roll over itself when the porous structure 106 is withdrawn into the elongate shaft 102.

[0061] FIG. 1C shows a first cross sectional view of a soft tissue region of a body that includes a cavity 120 and a channel 122 that leads to the cavity 120. The soft tissue region may be a surgical site, such as a postpartum uterus or a site of removal for tumor. For example, the channel 122 may include a portion of a vaginal canal and the cavity may include a postpartum uterus. FIG. ID shows a second sectional view (taken at 90 degrees offset from the view shown in FIG. 1C). As shown, tissue may be open more in one direction than another.

[0062] FIG. IE shows the apparatus 100 after being inserted within the body region and as a negative pressure (suction) is applied. As shown, the porous structure 106 is positioned within the cavity 120 and the elongate shaft 102 is positioned within the channel 122. In some cases, the porous structure 106 may at least partially change shape (e.g., bend) when inserted within the cavity 120, for example, by pressure from contact with surrounding tissue. In some cases, the porous structure 106 may be configured to take on a pre-determined shape (e.g., bent shape), for example, to conform to a shape of a particular body cavity.

[0063] In the example shown, the second elongate shaft 103 that is coupled to the porous structure 106 is advanced through the lumen of an elongate member 102 to distally extend the porous structure 106 out of the elongate shaft 102 and into the cavity 120. The elongate shaft 102 may form a seal with the walls of the soft tissue walls of the channel 122 so that sufficient negative pressure can form within the cavity 120.

[0064] In some examples, the elongate shaft 102 may include one or more plugs around an outer diameter of the elongate shaft 102 to create a seal with surrounding tissue of the channel 122. The one or more plugs may be configured to allow the elongate shaft 102 to be positioned within the channel 122 while reducing damage to surrounding tissue. For example, the plugs may be made of a compressible material that may take on a compressed state when inserted within the channel 122 and that may be expanded once within the channel 122 to create the seal.

[0065] Once the porous structure 106 is positioned within cavity 120 and a seal is formed, a negative pressure may be applied through the lumen of the elongate shaft 102 to cause fluid and/or other bodily material from the cavity 120 to flow proximally through the porous structure 106, into the elongate shaft 102, and out of the body. For example, the elongate shaft 102 may include one or more openings at a distal end of the elongate shaft (and/or within a side wall in a distal region of the elongate shaft 102). The porous structure 106 can maintain a shape that provides efficient flow of fluid and/or gas through the network of pores of the porous structure 106, even when compressed by the tissue, as shown in FIG. IE. The negative pressured applied by the porous structure 106 may apply in inward force on the surrounding walls of the cavity 120 (indicated by inward facing arrows in FIG. IE), thereby causing the cavity 120 (e.g., uterus) to at least partially contract. Such contraction may be beneficial, for example, in cases where contracting a postpartum uterus may reduce hemorrhaging.

[0066] In some cases where the porous structure 106 has tubular shape, application of the negative pressure may flatten the outer shape of the tube, creating a flattened tube shape. However, the pores of the porous structure may sufficiently maintain their shape to allow fluid, material and/or air to pass therethrough.

[0067] The porous structure 106 may be removed from the cavity 120 by proximally moving the porous structure 106 out of the cavity 120. In cases where the porous structure 106 is a rolling porous structure, the porous structure 106 may be inverted and retracted within the elongate shaft 102. In some cases, retraction into the elongate shaft 102 may cause the porous structure 106 to radially contract. In other examples where the second elongate shaft 103 is not used, the elongate shaft 102 may be pulled to directly pull the porous structure 106 out of the cavity 120. In examples in which a collapsible plug is included as part of the apparatus, the plug may optionally be collapsed before or as the apparatus is removed from the body.

[0068] The negative pressure may be maintained for a period of time to provide a therapeutic benefit. For example, the negative pressure may be applied until the cavity 120 is sufficiently drained of fluid and/or the cavity 120 is sufficiently contracted. In some examples, the period of time may range from one minute to several hours or even days. For example, the period of time may range from one minute to 5 days or more (e.g., 10 minutes, 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours, or 10 hours, 12 hours, 18 hours, 24 hours, 48 hours, 3 days, 4 days, 5 days, etc.).

[0069] In some examples, the negative pressure is optionally maintained within the cavity 120 for a period of time after withdrawing the porous structure 106 from the cavity 120. For example, in some cases, maintaining the negative pressure after removal of the porous structure 106 may help to contract a uterus and mitigate uterine hemorrhaging. In some examples, the negative pressure may be applied period of time may range from one minute to 10 hours (e.g., 10 minutes, 30 minutes, 1 hour, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 8 hours, or 10 hours) after withdrawal of the porous structure 106 from the cavity 120. The negative pressure may be applied via the elongate shaft 102 and/or the second elongate shaft 103 after withdrawing the porous structure 106.

[0070] In some examples in the treatment for postpartum hemorrhage, negative pressure may typically be applied to stop the bleeding. In some cases, the bleeding may stop within a minute. The practitioner may make a visual inspection of when the bleeding stops. The negative pressure may be maintained from about one to 8 hours to contract the uterus. The practitioner may feel the patient’s abdomen to determine whether the abdomen has hardened, indicating that the uterus is contracted. Additionally or alternatively, the practitioner may use ultrasound or other imaging techniques to determine contraction of the uterus. For example, negative pressure may be applied for between about 30 minutes to about 8 hours. In some examples, negative pressure may be applied for about 1 hour of vacuum then the medical professional may check for bleeding and reapply the negative pressure if needed. This process may be repeated as necessary. Checking for bleeding may include checking through a window of the apparatus.

[0071] In any of the apparatuses, one or more of the elongate shafts may be flexible, semi-ridged or rigid. For example, the elongate shaft(s) may be formed of flexible polyurethane or silicone. These apparatuses may be configured to have a high column force while retaining lateral bending flexibility.

[0072] In any of the examples, the proximal direction may be the direction towards the hand of the user (e.g., physician, surgeon, medical technician, nurse, etc.) operating the device, and distal may be the direction away from the hand of the user.

[0073] Any of the porous structures described herein may have an open pore structure in which pores/holes/spaces within the porous structure are interconnected to provide multiple channels throughout the porous structure. In some examples, the porous structure includes textile material, such as a woven, braided, knitted and/ or non-woven material. Examples of non-woven materials may include porous sheets of polymer, felt, melt-blown, and/or foam (e.g., open cell) material. In some examples, the porous structures may be formed of a knit, a weave, a braid, a non-woven sheet (e.g., polymer or metallic or mixes) of material having pores. For example, in variations in which the porous structure is formed of a braided material, the braid may include any number of filaments, e.g., between 24-144 ends/filaments (e.g., between about 24-128 filaments, between about 32-98 filaments, etc.).

[0074] In some examples, the textiles are formed of a material such as polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), nylon, polypropylene, nitinol, steel, elgiloy, silicone, polyurethane, a nickel-cobalt base superalloy (e.g., MP35N®) or any combination of these materials. In some examples, the polytetrafluoroethylene (PTFE) may include an expandable PTFE (ePTFE).

[0075] The filaments of the textiles may be any appropriate diameters, such as between 0.003” to 0.025” diameter filaments (e.g., monofilaments or compound filaments). In some examples, the porous structure is formed of filaments (knit, woven, braided, etc.) of between 100-2000 denier (e.g. multifilament or monofilament). The textile may have a mono or multi filament structure (or a mixture thereof). In some examples, the filaments are metal filaments (e.g., nitinol, steel elgiloy, and/or nickel-cobalt base superalloy) having a diameter ranging from about 0.001 inches to about 0.01 inches.

[0076] In some examples flat tape-like strips (slit films used to make basket like weaves) are used. In some examples, the porous structures may include textile that is formed into tube having a cylindrical shape or a flattened tube shape. In some cases, the textile is in the form of a flat sheet. In some cases, the textile is in the form of a double layer wall tube (e.g., tube inside tube).

[0077] In some examples, the porous structure is made of a non-textile material. For example, the porous structure may include one or more tubes. In some cases, the tube(s) are extruded tubes (formed by extrusion). The thickness of the walls of the tube may range from about 0.003 inches to about 0.125 inches. In some examples, the non-textile tube(s) may be made of one or more polymers (e.g., PET, nylon, polypropylene, PTFE, PTFE (e.g., ePTFE), silicone, and/or polyurethane). The non-textile tube may include holes (e.g., slots, slits, round holes) that form the pores of the porous structure. In some examples, the holes may be formed by laser cutting. The holes may be formed into one or more patterns. The size of the holes may vary. In some examples, the holes have diameters ranging from about 1 millimeter (mm) to about 4 mm. In some examples, the density of the holes (holes per unit area) of holes having diameters of 1 mm or less is about ten holes per cm² or greater. In some examples, the holes are punched or stamped holes having diameters ranging from about 1 mm to 4 mm. [0078] In some examples, the non-textile material is made of one or more foam tubes and/or one or more sheets. The foam may have an open cell structure to allow fluid/material to flow therethrough. The open cell structure may be configured to allow for two flow pathways (along the wall and through the wall), as described herein. In some examples, the foam tube(s) and/or sheet(s) may include multiple layers. For example, the porous structure may include a tube(s) inside another tube(s).

[0079] The porous structure structures described herein may have any of a number of shapes. In some examples, the porous structure may have a tubular shape with an inner space (e.g., lumen). In some cases, the porous structure may include multiple tubes of porous material (e.g., concentrically arranged). In some examples, the porous structure may have a non-tubular structure, for example, where the porous material is throughout the thickness of the porous structure (i.e., does not include an inner lumen).

[0080] FIGS. 2A-2G show side views of example apparatuses having different tubular porous structure structures when in extended and/or expanded states. Each of the tubular porous structure structures shown in FIGS. 2A-2G has a porous wall (e.g., mesh wall) that is shaped in a tube such that porous wall defines an inner lumen. The porous wall has many pores that are configured to allow fluid, materials and/or gas to pass therethrough when a negative pressure is applied. Each of the tubular porous structures are coupled to a distal end region of a corresponding elongate shaft. In each figure, a suction can be applied in a proximal direction (e.g., via the elongate shaft coupled thereto, or another elongate shaft) to provide a negative pressure on the tubular porous structure. Each of these examples may include multiple adjacent layers of porous material. The multiple layers may be formed by inverting a tube of the porous material back over itself or it may be formed by concentrically placing one or more tubes, bags or sheets of porous material into another tube or bag of porous material. Suction may be applied within the innermost channel (e.g., innermost tube or bag of porous material, e.g., mesh), so that suction passes through the multiple layers. [0081] FIGS. 2A-2G show example drain apparatuses with porous structures having nonrolling configurations. In some examples, the porous structures of FIGS. 2A-2G are made of a fabric material. FIG. 2A shows a porous structure configured as a tube or sheet of porous material that is connected to a tube (also referred to herein as an elongate shaft having a lumen). FIG. 2B shows a porous structure configured as a wide tube or sheet of porous material, for example, that is configured to compress during insertion into the body and to expand once in a body cavity. FIG. 2C shows a porous structure configured as a narrow tube or sheet of porous material that is narrower than a diameter of the tube. FIG. 2D shows a porous structure having a tapered tube shape, where a distal portion of the porous structure is wider than a proximal portion of the porous structure. FIG. 2E shows a porous structure having a tapered tube shape, where a distal portion of the porous structure is narrower than a proximal portion of the porous structure. FIG. 2F shows a porous structure having multiple tubes made of porous material. The example of FIG. 2F has two porous tubes; however, in other examples the porous structure may include any number of tubes (e.g., 1, 2, 3, 4, 5, 6, 7 or more). FIG. 2G shows a porous structure configured as a looped tube or sheet of porous material. The example of FIG. 2B has one loop of porous material; however, in other examples the porous structure may include any number of loop of porous material (e.g., 1, 2, 3, 4, 5, 6, 7 or more). [0082] FIGS. 3A-3E show end views and side views of example drain apparatuses with non-rolling porous structures, where at least a portion of the porous structure is covered with a cover that may act as a barrier (or partial barrier) to reduce fluid flow rate. The cover may also be referred to as a barrier or sheath. The porous structures of FIGS. 3 A-3E have a round cross-section (cylindrical) tube shapes. In other examples, the porous structure may have a non-round cross section (non-cylindrical) shape (e.g., square, star shaped, moon shaped, or flat strip). FIG. 3 A shows a porous structure configured as a tube without a cover. FIG. 3B shows a porous structure configured as a tube where the sides of the porous structure are covered by an impermeable cover such that fluid can flow into porous structure via an open end of the cover. FIG. 3C shows a porous structure configured as a tube that is covered by a cover having pores. FIG. 3D shows a porous structure configured as a tube that is covered by an impermeable cover that only partially covers (i.e., one side of) the porous structure. FIG. 3E shows a porous structure configured as a tube that is partially covered (i.e., two sides) by an impermeable. In some examples, the covers are a condom-like material, thin film, and/or a detached sheath. The covers may include any of a number of materials. In some examples, the covers are made of a flexible (e.g., elastic) polymer material (e.g., polyurethane and/or silicone).

[0083] FIGS. 4A-4E show end views and side views of example drain apparatuses having porous structures (e.g., textile or foam) of different shapes. FIG. 4A shows a porous structure having an open ended round (cylindrical) tube shape. FIG. 4B(a) shows a porous structure having a close ended round (cylindrical) tube shape. FIG. 4B(b) shows a porous structure having a close ended flat tube or sheet. FIG. 4C shows a solid porous structure (e.g., made of open cell foam). FIG. 4D shows a porous structure having a flat (e.g., sheet) shape. FIG. 4E shows a porous structure having a round or flat rolling tube shape.

[0084] FIGS. 5 A and 5B show end views and side views of an example rolling drain apparatus. The porous structure may have a round or flat tube shape. In some cases, the porous structure is made of a porous fabric. FIG. 5 A shows the tube shaped porous structure in a state where a tube (which supplies suction) is extended within the tube shaped porous structure. The tube may have a single open distal end or multiple pores (e.g., slits) that are in fluid communication with the porous structure. FIG. 5B shows the tube shaped porous structure extended distally from the distal end of the tube and partially inverted. The porous structure may be pulled proximally within the tube to cause the porous structure to invert (as indicated by the curved arrows).

[0085] FIG. 6 shows an example rolling drain apparatus having an optional plug positioned around the outside of the tube. The plug may be made of a soft expandable/contractable material (e.g., foam). In some cases, the plug may have a sheath (e.g., impermeable) covering the soft expandable/contractable material. The plug may have any shape, such as sphere, disk, cone, or a football shape. In some examples, multiple plugs may be used. The plug may be used to provide a seal with surrounding tissue, for example, within a body canal (e.g., cervix).

[0086] FIGS. 7A and 7B show an example of a spiral rolling drain apparatus. The spiral configuration provides a way of decreasing a diameter of the porous structure when inserting it into or removing it from the patient’s body. The tube may be rotated/twisted to “wrap” the roll of porous structure tighter or expand the roll of porous structure. FIG. 7A shows the porous structure in a contracted state. Spiral axial rolling constrains the roll of porous structure in the radially contracted state. FIG. 7B shows the porous structure in an expanded state. Rotating the roll of porous structure in the opposite direction causes the roll of porous structure to unroll and unconstrain the porous structure.

[0087] FIGS. 8A and 8B show an example of a drain apparatus having a large expandable porous structure. The porous structure may be made of a textile, open cell foam and/or sponge material. FIG. 8 A shows the porous structure in a contracted state constrained by an outer sheath, for example during insertion and withdrawal of the porous structure into and out of the patient’s body. FIG. 8B shows the porous structure in an expanded state where it is extended distally out of the sheath. In this example, the distal end of the sheath includes a flexible slotted tip that has a rounded/blunted shape while the porous structure is housed within the sheath (FIG. 8A). The rounded/blunted shape of the slotted tip can allow for atraumatic insertion into the patient’s body. The slotted tip is configured to flex outward to allow the porous structure to extend out of the distal end of the sheath (FIG. 8B).

[0088] FIG. 8C shows a variation of the drain apparatus of FIGS. 8A and 8B. In this example, the distal end of the sheath has a blunt tip for atraumatic insertion into the patient’s body.

[0089] FIGS. 9A-9C show an example use of a drain apparatus for treating a body region. The drain apparatus is similar to the drain apparatus of FIGS. 8A and 8B except that it includes an optional plug positioned around the out circumference of tube (e.g., first elongate shaft). As described herein, the plug (e.g., foam or sponge) may be configured to radially compress when within the sheath and expand when released from the sheath. In some cases, the plug may include an outer film made of a flexible polymer material (e.g., ePTFE) and/or a dense textile material. In some cases, the outer film may include a coating to make the outer surface of the plug slippery. In some cases, the shape of the plug may be tapered (e.g., umbrella like shape as shown in FIGS. 9A-9C). In some cases, there may be multiple plugs (e.g., spares).

[0090] FIG. 9A shows the apparatus being inserted into a channel (e.g., cervix) that leads to an empty space (e.g., of a uterus or wound). FIG. 9B shows the retraction (sliding back) of the sheath to expose the porous structure and cause expansion of the porous structure within the empty space. In the expanded state, the porous structure may have a relatively large volume, for example, to provide more contact with walls of the body region (e.g., uterus or wound). In some cases, the expanded porous structure has a shape that matches the interior dimensions of the body region. The plug may be self-expanding or may expand with expansion of the porous structure. The plug creates a seal with surrounding tissue so that negative pressure may be maintained within the body region. The contact of the plug with surrounding tissue may also create a bearing surface to aid in the compaction of the plug when it is later compressed down for re-sheathing. FIG. 9C shows negative pressure being applied through the tube and porous structure to contract surrounding tissue of the body region (e.g., walls of the uterus).

[0091] FIGS. 10A1-10A4 show an example of how a drain apparatus with a tubular porous structure 1006 (e.g., textile or non-textile) can provide fluid paths for drawing fluid and/or other materials. The tubular porous structure 1006 is in fluid communication with an elongate shaft 1002 (e.g., tube). FIGS. 10A1 and 10A2 show a distal end view and a side view of the apparatus when a negative pressure is applied within the elongate shaft 1002 (e.g., as indicated by arrows). The negative pressure creates flow 1050 of fluid and/or other material though the network of pores of the porous walls 1016, 1055 of tubular porous structure 1006 and into an inner space 1009 (e.g., lumen) of the tubular porous structure 1006. Once in the inner space 1009, the flow 1050 is directed proximally toward the elongate shaft 1002 and eventually out of the body cavity being drained and/or contracted. In addition, the relatively high porosity of the porous structure 1006 allows for efficient flow axially along/through the walls 1016, 1055 down the length of the porous structure 1006 in the proximal direction toward the elongate shaft 1002. In this way, the porous structure 1006 provides multiple fluid flow channels.

[0092] FIGS. 10A3 and 10A4 show a distal end view and a side view of the apparatus when at least a portion of the tubular porous structure 1006 is radially compressed/flattened such that the inner space 1009 is reduced or eliminated. The flow 1050 of fluid and/or gas can flow axially along the porous wall 1016, 1055 of tubular porous structure 1006 in the proximal direction toward the elongate shaft 1002 even though the inner space 1009 is reduced or eliminated. This aspect may allow the apparatus to function in situations where at least a portion of the tubular porous structure 1006 becomes compressed by surrounding tissue while in the body cavity. In addition, the network of pores in the porous walls 1016, 1055 provides many nooks and crannies down the length of the tubular porous structure 1006 that can create a wicking effect, which may cause the fluid to travel faster. If the porous structure 1006 is made of a fabric, the fabric wall thickness may behave like an open cell foam.

[0093] FIGS. 11 A- 11 J show examples of surgical drains with different textile porous structures. In each example, each porous structure extends from a distal end of an elongate shaft (tube). FIG. 11 A shows a porous structure in the form of a sheet of textile material. FIG. 1 IB shows a porous structure including multiple strips of thermoplastic polyurethane (TPU) extending from a textile tube. FIG. 11C shows a porous structure including slices/strips (in this example, 4 slices) of foam extending from a textile tube. FIG. 1 ID shows a porous structure including looped flat braid sheets or tubes. FIG. 1 IE shows a porous structure including multiple small tubes of braid. FIG. 1 IF shows a porous structure including a rolling porous structure with two looped braids under double tubes (tube inside tube). FIG. 11G shows a porous structure including multiple (in this example, 8) “fingers” of textile strips. FIG. 11H shows a porous structure including big braid loops. FIG. I ll shows a porous structure including bundled together rope. FIG. 11 J shows a porous structure including a textile sheet rolled into a tube and tied to an outside of the tube and also tied to an internal elongate shaft (e.g., pusher). The sheet can be a braid, woven, knit, or warp knit.

[0094] The following are some example characteristics of textile porous structure variations:

• Woven Tube

• Monofilament Warp Yarns (.01” diameter PET)

• Monofilament Weft Yams (.01” diameter PET)

• Plain woven tube (20 picks per inch)

• Woven tube OD 12mm

• Braid

• .01” Monofilaments

• 120 ends

• 45ppi

• 12mm OD

• Knit

• .01” PET monofil

• Circular knit • 36 needle head

• Non-Woven (porous sheets (ePTFE/Punched/slitted), felt, foam)

• Open cell (reticulated)

• Thermoplastic or thermoset foams

• Similar to wound dressing foams used with negative pressure

• Foam can be reinforced with open textile structure (net like tubes, sheets) to hold foam together when placed under tension. Foam composite or fabric covered foam

[0095] FIGS. 12A-12F show examples of surgical drains with different non-textile porous structures. In each example, each porous structure extends from a distal end of an elongate shaft (tube). FIG. 12A shows a porous structure in the form of an open cell foam bag fastened over the end of the tube. FIG. 12B shows a porous structure in the form of high porosity foam cylinder inside an optional textile material (the foam cylinder could be alone). FIG. 12C shows a porous structure that constitutes a distal part of the tube with revolving cuts formed therein. FIG. 12D shows a porous structure that constitutes a distal part of the tube with holes formed therein. FIG. 12E shows a porous structure in the form of a spiral slotted tube that is looped. FIG. 12F shows a porous structure in the form of a non-woven sheet or tube of material.

[0096] FIGS. 13A-18C show examples of porous structures in the form of porous tubes. The tubes have a pattern of holes formed using, e.g., laser cutting, punching, stamping, or other manufacturing process(es). In some examples, the walls of the tubes may have a thickness ranging from about 0.1 mm to about 5 mm. The tubes may be made of one or more polymer materials. In some examples, the polymer(s) include one or more elastomers. The polymers may have a Shore 00 durometer ranging from 20-80 and/or a Shore A durometer ranging from 10-80. The tubes may have a high permeability (e.g., more than 50% more open than the polymer itself). In some examples, the tubes are made of a foam material made of a polymer (e.g., thermoset or thermoset).

[0097] FIGS. 13A-13D, 14A-14D and 15A-15E show porous tubes having various lattice patterns of openings. FIGS. 16A-16C show a porous tube having multiple “X” shaped openings FIGS. 17A-17D show a porous tube having multiple “S” shaped openings. FIGS. 18A-18C show a porous tube having multiple round openings.

[0098] The following are some example characteristics of non-textile porous structure variations:

• Extruded Tube (thick or thin walled, .003” to .125”) • Polymers (PET, Nylon, Polypropylene, PTFE, ePTFE, Silicone, Polyurethane, TPU, PVC . . . )

• Laser Slotted pore patterns (1mm to 4mm holes) like perforated structures (many holes per unit area, sub 1mm Holes/10 plus holes cm^A2) Examples shown in slides 26-31

• Punched/stamped: (1mm to 4mm holes)

• Slits: 1mm width to 3mm width by 1mm long to 15mm long

• Foam tubes or sheets, open cell

• TPU (shape memory foam), stiffness change with exposure to heat (heat increase/stiffness decrease)

• Thermoset foam, heat stable (Polyurethane, phenol-formaldehyde, ureaformaldehyde)

• Pore size ranging from ,lmm-5mm

• Low density (high porosity)

• Coil Spring like structures

• Tube shapes (extension or compression shape) or flat springs (saw tooth like shapes)

• Spring inside spring

• Springs rotating in the same direction

• Springs rotating in counter directions

[0099] When a feature or element is herein referred to as being “on” another feature or element, it can be directly on the other feature or element, or intervening features and/or elements may also be present. In contrast, when a feature or element is referred to as being “directly on” another feature or element, there are no intervening features or elements present. It will also be understood that, when a feature or element is referred to as being “connected”, “attached” or “coupled” to another feature or element, it can be directly connected, attached or coupled to the other feature or element or intervening features or elements may be present. In contrast, when a feature or element is referred to as being “directly connected”, “directly attached” or “directly coupled” to another feature or element, there are no intervening features or elements present. Although described or shown with respect to one embodiment, the features and elements so described or shown can apply to other embodiments. It will also be appreciated by those of skill in the art that references to a structure or feature that is disposed “adjacent” another feature may have portions that overlap or underlie the adjacent feature. [0100] Terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. For example, as used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items and may be abbreviated as “/”.

[0101] Spatially relative terms, such as “under”, “below”, “lower”, “over”, “upper” and the like, may be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. It will be understood that the spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientation depicted in the figures. For example, if a device in the figures is inverted, elements described as “under” or “beneath” other elements or features would then be oriented “over” the other elements or features. Thus, the exemplary term “under” can encompass both an orientation of over and under. The device may be otherwise oriented (rotated 90 degrees or at other orientations) and the spatially relative descriptors used herein interpreted accordingly. Similarly, the terms “upwardly”, “downwardly”, “vertical”, “horizontal” and the like are used herein for the purpose of explanation only unless specifically indicated otherwise.

[0102] Although the terms “first” and “second” may be used herein to describe various features/elements (including steps), these features/elements should not be limited by these terms, unless the context indicates otherwise. These terms may be used to distinguish one feature/element from another feature/element. Thus, a first feature/element discussed below could be termed a second feature/element, and similarly, a second feature/element discussed below could be termed a first feature/element without departing from the teachings of the present invention.

[0103] Throughout this specification and the claims which follow, unless the context requires otherwise, the word “comprise”, and variations such as “comprises” and “comprising” means various components can be co-jointly employed in the methods and articles (e.g., compositions and apparatuses including device and methods). For example, the term “comprising” will be understood to imply the inclusion of any stated elements or steps but not the exclusion of any other elements or steps. [0104] In general, any of the apparatuses and methods described herein should be understood to be inclusive, but all or a sub-set of the components and/or steps may alternatively be exclusive, and may be expressed as “consisting of’ or alternatively “consisting essentially of’ the various components, steps, sub-components or sub-steps. [0105] As used herein in the specification and claims, including as used in the examples and unless otherwise expressly specified, all numbers may be read as if prefaced by the word “about” or “approximately,” even if the term does not expressly appear. The phrase “about” or “approximately” may be used when describing magnitude and/or position to indicate that the value and/or position described is within a reasonable expected range of values and/or positions. For example, a numeric value may have a value that is +/- 0.1% of the stated value (or range of values), +/- 1% of the stated value (or range of values), +/- 2% of the stated value (or range of values), +/- 5% of the stated value (or range of values), +/- 10% of the stated value (or range of values), etc. Any numerical values given herein should also be understood to include about or approximately that value, unless the context indicates otherwise. For example, if the value “10” is disclosed, then “about 10” is also disclosed. Any numerical range recited herein is intended to include all sub-ranges subsumed therein. It is also understood that when a value is disclosed that “less than or equal to” the value, “greater than or equal to the value” and possible ranges between values are also disclosed, as appropriately understood by the skilled artisan. For example, if the value “X” is disclosed the “less than or equal to X” as well as “greater than or equal to X” (e.g., where X is a numerical value) is also disclosed. It is also understood that the throughout the application, data is provided in a number of different formats, and that this data, represents endpoints and starting points, and ranges for any combination of the data points. For example, if a particular data point “10” and a particular data point “15” are disclosed, it is understood that greater than, greater than or equal to, less than, less than or equal to, and equal to 10 and 15 are considered disclosed as well as between 10 and 15. It is also understood that each unit between two particular units are also disclosed. For example, if 10 and 15 are disclosed, then 11, 12, 13, and 14 are also disclosed.

[0106] Although various illustrative embodiments are described above, any of a number of changes may be made to various embodiments without departing from the scope of the invention as described by the claims. For example, the order in which various described method steps are performed may often be changed in alternative embodiments, and in other alternative embodiments one or more method steps may be skipped altogether. Optional features of various device and system embodiments may be included in some embodiments and not in others. Therefore, the foregoing description is provided primarily for exemplary purposes and should not be interpreted to limit the scope of the invention as it is set forth in the claims.

[0107] The examples and illustrations included herein show, by way of illustration and not of limitation, specific embodiments in which the subject matter may be practiced. As mentioned, other embodiments may be utilized and derived there from, such that structural and logical substitutions and changes may be made without departing from the scope of this disclosure. Such embodiments of the inventive subject matter may be referred to herein individually or collectively by the term “invention” merely for convenience and without intending to voluntarily limit the scope of this application to any single invention or inventive concept, if more than one is, in fact, disclosed. Thus, although specific embodiments have been illustrated and described herein, any arrangement calculated to achieve the same purpose may be substituted for the specific embodiments shown. This disclosure is intended to cover any and all adaptations or variations of various embodiments. Combinations of the above embodiments, and other embodiments not specifically described herein, will be apparent to those of skill in the art upon reviewing the above description.

Claims

CLAIMS What is claimed is:

1. A surgical drain apparatus comprising: an elongate shaft having a lumen extending therethrough; and a porous structure extending from a distal end of the elongate shaft, wherein the porous structure defines a plurality of pores that are arranged to provide a fluid pathway from an outer surface of the porous structure to the lumen of the elongate shaft, wherein the porous structure is sufficiently flexible to bend laterally upon positioning of the porous structure within a body cavity, and wherein the outer surface of the porous structure has a pore area that is at least two times a cross section area of the lumen of the elongate shaft, wherein a ratio of an axial length of the porous structure to the cross section of the lumen of the elongate shaft ranges from about 5 to about 100, further wherein the porous structures has a porosity ranging from 60% to 85%.

2. The surgical drain apparatus of claim 1, wherein the porous structure is coupled to a distal end of a rod that is configured to move axially within the suction lumen of the elongate shaft, wherein moving the rod distally with respect to the elongate shaft causes the porous structure to extend out of the distal end of the elongate shaft.

3. The surgical drain apparatus of claim 1, wherein the porous structure comprises one or both of a mesh and a foam.

4. The surgical drain apparatus of claim 1, wherein the plurality of pores comprises one or more of a plurality of holes, a plurality of slots, or a plurality of slits.

5. The surgical drain apparatus of claim 1, wherein the porous structure comprises one or both of a textile material and a non-textile material.

6. The surgical drain apparatus of claim 1, wherein the porous structure is an invertible rolling tube.

7. The surgical drain apparatus of claim 1, further comprising a plug on an outer surface of the elongate shaft that is configured to provide a seal with surrounding tissue.

8. The surgical drain apparatus of claim 7, wherein the plug is made of a compressible and self-expanding material.

9. A surgical drain apparatus comprising: an elongate shaft having a lumen extending therethrough; and a porous structure extending from a distal end of the elongate shaft, wherein the porous structure defines a plurality of pores that are arranged to provide a fluid pathway from an outer surface of the porous structure to the lumen of the elongate shaft, wherein the porous structure is sufficiently flexible to bend laterally upon positioning of the porous structure within a body cavity, and wherein the outer surface of the porous structure has a pore area that is at least two times a cross section area of the lumen of the elongate shaft.

10. The surgical drain apparatus of claim 9, wherein a ratio of an axial length of the porous structure to the cross section of the lumen of the elongate shaft ranges from about 2 to about 100.

11. The surgical drain apparatus of claim 9, wherein the porous structures has a porosity ranging from 60% to 85%.

12. The surgical drain apparatus of claim 9, wherein the porous structure is coupled to a distal end of a rod that is configured to move axially within the suction lumen of the elongate shaft, wherein moving the rod distally with respect to the elongate shaft causes the porous structure to extend out of the distal end of the elongate shaft.

13. The surgical drain apparatus of claim 9, wherein the porous structure comprises one or both of a mesh and a foam.

14. The surgical drain apparatus of claim 9, wherein the plurality of pores comprises one or more of a plurality of holes, a plurality of slots, or a plurality of slits.

15. The surgical drain apparatus of claim 9, wherein the porous structure comprises one or both of a textile material and a non-textile material.

16. The surgical drain apparatus of claim 9, wherein the porous structure is an invertible rolling tube.

17. The surgical drain apparatus of claim 9, further comprising a plug on an outer surface of the elongate shaft that is configured to provide a seal with surrounding tissue.

18. The surgical drain apparatus of claim 17, wherein the plug is made of a compressible and self-expanding material.

19. A method of draining a body region, comprising: positioning a porous structure into the body region, wherein the porous structure extends distally from a lumen of an elongate shaft, wherein the outer surface of the porous structure has a pore area that is at least two times a cross section area of the lumen of the elongate shaft, and further wherein the porous structure is sufficiently flexible to bend laterally upon positioning of the porous structure within the body region; creating a seal around the elongate shaft to maintain a vacuum within the body region; and applying negative pressure through the lumen so that a plurality of flow paths are created through from an outer surface of the porous structure to the lumen of the elongate shaft.

20. The method of claim 19, wherein a ratio of an axial length of the porous structure to the cross section of the lumen of the elongate shaft ranges from about 2 to about 100.

21. The method of claim 19, wherein the porous structures has a porosity ranging from 60% to 85%.

22. The method of claim 19, wherein a first end of the porous structure is coupled to the elongate shaft and a second end of the porous structure is coupled to a rod that is configured to slide within the lumen of the elongate shaft, wherein positioning the porous structure into the body region comprises moving the rod distally within the lumen of the elongate shaft until the porous structure extends distally from the lumen.

23. The method of claim 19, wherein the porous structure comprises one or both of a mesh and a foam.

24. The method of claim 19, wherein the plurality of pores comprises one or more of a plurality of holes, a plurality of slots, or a plurality of slits.

25. The method of claim 19, wherein the porous structure comprises one or both of a textile material and a non -textile material.

26. The method of claim 19, wherein the porous structure is a tubular porous structure, wherein positioning the porous structure into the body region comprises causing the tubular porous structure to at least partially invert.

27. The method of claim 19, wherein an outer surface of the elongate shaft comprises a plug, wherein creating the seal comprises expanding the plug to form the seal with surrounding tissue.

28. The method of claim 19, wherein the plug is radially compressed when positioned within the surrounding tissue, wherein the plug self-expands to contact the surrounding tissue.