Patent Publication Number: US-2020297386-A1

Title: Material removal from a lung or bronchial tree

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 15/356,975, titled BLOCKAGE REMOVAL, filed on Nov. 21, 2016, which claims the benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62/260,873, titled Treating Esophageal Food Impactions, filed on Nov. 30, 2015; the entire contents of each of the foregoing applications are hereby incorporated by reference herein. 
    
    
     BACKGROUND 
     Blockages within the body can take various forms. For example, esophageal food impactions are one of the most common and dangerous emergencies in gastroenterology, with an annual incidence rate of at least 13/100,000 population (Longstreth, GIE; 2001); moreover, the incidence has been increasing in recent years due to the recent rise in eosinophilic esophagitis (Desai, GIE; 2005). Food impactions can occur when a bolus of swallowed food becomes lodged in the esophagus and is unable to pass spontaneously into the stomach. This occurs either when the swallowed bolus is too large or when there are diseases of the esophagus that narrow the esophageal lumen, such as GE reflux with a stricture or ring, an esophageal food allergy such as eosinophilic esophagitis with stricture or stenosis of the esophagus, a Schatzki&#39;s ring, esophageal webs or esophageal cancer. Motility disorders of the esophagus typically do not cause impactions. 
     Most impactions clear spontaneously, but a significant fraction (20%) will not and will require emergent endoscopic intervention to clear the blocked food. This can be dangerous, since emergency endoscopy with removal of food can result in serious complications including aspiration pneumonia, laceration of the esophagus with bleeding, or esophageal perforation which can result in sepsis and death. The complication rate of endoscopic clearance of a food impaction is approximately 3-5% and the mortality rate is unknown but several deaths have been reported (Simic, Am J Forensic Med Path; 1988). 
     Food impactions present acutely and dramatically, with patients noting chest pain or pressure, inability to swallow, painful swallowing, a sensation of choking, and neck or throat pain. Retching and vomiting are also common, and patients can also experience breathing problems due to tracheal or airway compression, with stridor, coughing or wheezing being noted. 
     There are various endoscopic tools used to clear impactions but all have flaws and there is no current technique that is demonstrably better than any other. Food can sometimes be pushed blindly through the esophagus and into the stomach using the tip of the endoscope, but this technique is performed without vision of the more distal esophagus, so the endoscopist has no way of knowing what the esophagus looks like distal to the obstruction or what abnormalities exist. This technique can work well (Vicari, GIE; 2001), but because the technique is blind, can often result in esophageal laceration or perforation. Many endoscopists avoid blind pushing for this reason. Forceps including “rat-tooth” type designs, snares and variable wire basket designs can be used to break up food into smaller pieces for extraction, but these techniques are laborious, time-consuming and often fail. 
     Other extraction techniques can also be tried, particularly when the food bolus is not tightly wedged and is firm, or if the food contains bone or sharp surfaces. In this regard, baskets, snares, graspers, “pelican” forceps with longer arms, nets etc., can be used to remove food in whole or in pieces, but these techniques also frequently fail, and the patient is at risk for aspiration pneumonia if the pieces fall into the hypopharynx or mouth during the extraction attempts. If the food bolus is lodged proximally, then most of the above techniques will fail or are too dangerous to try. Endoscopic suction cannot be used for impactions, since chunks of food cannot be effectively suctioned through an endoscope, and also if suction fails to hold a bolus against the tip of the scope then a patient would be at high-risk for aspiration as the scope is withdrawn through the hypopharynx or mouth. Overtubes can be used if repeated endoscopic intubation is needed, but overtubes are uncomfortable, require deeper sedation and are dangerous in of themselves with risk of esophageal laceration and perforation. 
     Thus, it is important to provide mechanisms to clear blockages within the body. For example, within the field of esophageal food impaction, there is a need for effective and safer mechanisms to remove food stuck in the esophagus. 
     SUMMARY 
     Systems and methods are provided to address blockages within the body. 
     In one example, a device is configured to clear a bolus of food impacted within an esophagus, the device including a catheter tube having a hollow interior and a distal end configured to core the bolus of food and a proximal end configured to be coupled to a source of suction to clear the core. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
         FIG. 1  shows an example catheter for removing a blockage within a body of a person. 
         FIG. 2  shows an example system for removing a bolus of food or other debris lodged within an esophagus including the catheter of  FIG. 1 . 
         FIG. 3  shows a portion of the system of  FIG. 2  with the bolus of food or other debris being partially cored. 
         FIG. 4  shows an example distal end of the catheter for coring the bolus of food or other debris shown in  FIG. 1 . 
         FIG. 5  shows another example distal end of the catheter for coring the bolus of food or other debris shown in  FIG. 1 . 
         FIG. 6  shows a portion of an example catheter tube of  FIG. 1  coupled to a syringe. 
         FIG. 7  shows an example stylet of the system of  FIG. 2 . 
         FIG. 8  shows the stylet of  FIG. 7  positioned with the catheter of  FIG. 1 . 
         FIG. 9  shows another example catheter having a Y-fitting for removing a bolus of food or other debris lodged within an esophagus. 
         FIG. 10  shows another view of the catheter of  FIG. 9 . 
         FIG. 11  shows a proximal portion of the catheter of  FIG. 9  with a stylet advanced fully therethrough. 
         FIG. 12  shows another view of the proximal portion of the catheter of  FIG. 11 . 
         FIG. 13  shows another view of the proximal portion of the catheter of  FIG. 11  with the stylet partially removed therefrom. 
         FIG. 14  shows an enlarged view of a portion of the proximal portion of the catheter of  FIG. 13 . 
         FIG. 15  shows another view of the portion of the proximal portion of the catheter of  FIG. 14  with a cap of the suction port removed. 
         FIG. 16  shows a distal end of the catheter of  FIG. 15 . 
         FIG. 17  shows a distal end of the catheter of  FIG. 10 . 
         FIG. 18  shows another example embodiment of a stylet for removing a bolus of food or other debris lodged within an esophagus. 
         FIG. 19  shows an end portion of the stylet of  FIG. 18 . 
         FIG. 20  shows another example embodiment of a system for removing a bolus of food or other debris lodged within an esophagus. 
         FIG. 21  shows a portion of the device of  FIG. 20 . 
         FIG. 22  shows another example embodiment of a system for removing a bolus of food or other debris lodged within an esophagus. 
         FIG. 23  shows a cross-sectional view of a portion of the device of  FIG. 22 . 
         FIG. 24  shows another cross-sectional view of a portion of the device of  FIG. 22 . 
     
    
    
     DETAILED DESCRIPTION 
     Example devices and methods described herein address the removal of blockages within the body. Although some of the examples depicted herein relate to the removal of impactions within the esophagus, the inventions are not so limited. For example, the inventions described herein can also be used to remove or otherwise break-up other blockages within the body, such as those in the lungs. 
     Some of the systems described herein assist in resolving the buildup of pieces of food in the esophagus while minimizing the risk of aspiration. The systems are further designed in an atraumatic manner, helping to avoid esophageal laceration and perforation. One such approach consistent with the embodiments disclosed involves coring out the center of a food impaction. 
     For example, in one embodiment, the system includes a catheter (e.g., hollow) with a distal end that is delivered to the site of the blockage. The distal end is used to core out portions of the blockage until the blockage is reduced in volume in a piecemeal manner. The smaller volume blockage can then pass through the esophagus spontaneously and/or be more easily removed. In some examples, the catheter can be delivered to the blockage site through an endoscope or other similar device. 
     In certain examples, suction can be provided to remove the cored portions of the blockage. The suction can be provided at the proximal end of the catheter to cause the cored portions to be suctioned from the site of the blockage and passed through the catheter and discarded, thus minimizing a risk of food aspiration and preserving visualization. 
     Certain embodiments include aspects that allow cored portions of the food to be cleared should the portions become caught in the catheter while being suctioned away from the blockage site. In one example, a source of compressed air, such as a syringe, can be placed at the proximal end of the catheter, and air can be passed through the catheter to clear any portions caught in the catheter, via the distal end. 
     In addition, a stylet can be passed through the interior of the catheter to clear any portions of food caught therein. The stylet can also perform other functions, such as providing stiffness for the catheter during delivery of the catheter to the blockage site. Further, the stylet can be configured to assist in the manipulation of the blockage, such as by advancing the stylet into the blockage one or multiple times to create a nidus for coring and suctioning. 
     Referring now to  FIG. 1 , an example catheter  100  is shown. The catheter  100  includes a hollow catheter tube  102  that generally can be used to core out a portion of a blockage. Specifically, the catheter tube  102  includes a distal end  104  that is configured to contact and core the blockage one or more times. As the blockage is cored by the distal end  104  of the catheter tube  102 , the volume of the blockage is reduced until the blockage is reduced to a sufficient level to be passed through the esophagus spontaneously and/or removed. 
     The catheter tube  102  includes a proximal end  106  configured to be coupled to various devices. For example, as described further below, the proximal end  106  of the catheter tube  102  is configured to be coupled to a source of suction to allow the cored food portions to be suctioned and/or removed through the catheter tube  102 . In another example, the proximal end  106  of the catheter tube  102  is configured to be coupled to a source of pressurized air, such as a syringe, to allow any cored food stuck within the catheter tube  102  to be cleared. Other configurations are possible. 
     Referring now to  FIGS. 2-3 , the catheter  100  is shown within an example system  200  configured to remove a blockage  202  positioned within an esophagus  204  of a person. In this example, the blockage  202  (generally food or other debris, but could also be other blockages like blood or blood clots, mucus, etc.) has become caught within the esophagus  204 . 
     In the embodiment shown, the catheter  100  is delivered to the blockage  202  using an endoscope  210 . The endoscope  210  contains a channel that is generally hollow and allows the catheter  100  to be delivered through the endoscope  210  to the blockage  202 . Once the distal end  104  of the catheter tube  102  is in position, the endoscope  210  can be withdrawn or can remain in place as the blockage  202  is manipulated. 
     The catheter tube  102  of the catheter  100  is configured to be advanced so that the distal end  104  impacts the blockage  202  so as to reduce the volume of the blockage  202 , such as by repetitively coring the food. As the volume is reduced (such as is shown in  FIG. 3 ), the blockage  202  can be naturally passed through the esophagus  204  and into a stomach  206  of the person. 
     In example embodiments, the catheter tube  102  is at least semi-rigid but flexible, which allows the catheter tube to flex and/or bend during delivery through the endoscope, as the endoscope flexes and bends. This allows the catheter tube  102  to be directed more precisely as it is inserted to a desired location. 
     In some examples, the distal end  104  of the catheter tube  102  is configured to assist in the coring of the blockage  202 . For example, as shown in  FIG. 4 , the distal end  104  of the catheter tube  102  is tapered. Specifically, the distal end  104  includes an inner diameter  402  that is smaller than an inner diameter  404  of a portion  406  of the catheter tube  102 . In one example, the difference in diameters can be less than one-hundredth of a millimeter. Other sizes are possible. In addition, the walls of the catheter tube  102  can be thinned as the walls extend to the distal end  104 , as depicted. 
     This tapering of the distal end  104  can allow a core  410  of the blockage  202  that is formed by the distal end  104  to be more easily suctioned through the catheter tube  102 . Since the cores formed by the distal end  104  will typically have a diameter smaller than that of the portion  406 , the cores can be more easily suctioned through the catheter tube  102  for evacuation, as is illustrated by Poiseuille&#39;s law. 
     In another depiction shown in  FIG. 5 , the catheter tube  102  is formed of a first portion  502  at the distal end  104  having a smaller diameter, and a second portion  504  extending along a remainder of the catheter tube  102  having a larger diameter. This again allows the cores of the blockage  202  that are created by the first portion  502  to be smaller in diameter so that the cores can more easily pass through the remainder of the catheter tube  102  (i.e., the second portion  504 ). 
     In some examples, a tip  508  of the distal end  104  of the catheter tube  102  can be beveled and/or serrated. The tip  508  can take multiple forms, including a serrated edge, to shave bits of the blockage  202  off of the bolus to better aid suctioning. The tip  508  can help core the blockage. 
     For example, referring again to the system  200  depicted in  FIG. 2 , a source of suction can be applied to the proximal end  106  of the catheter  100  to allow the cores of the blockage  202  to be removed through the catheter tube  102 . Specifically, in the example provided, a vacuum line  220  can be coupled to the proximal end  106  of the catheter tube  102 . The vacuum line  220  can be coupled to a collection canister  222 , and the collection canister  222  is coupled to a suction line  224 . The suction line  224  is coupled to a source of suction, such as a hospital vacuum source. In this configuration, pieces of the blockage  202  that are cored or otherwise dislodged by the catheter tube  102  can thereupon be sucked up the catheter tube  102 , through the vacuum line  220 , and collected in the collection canister  222 . 
     As described previously, it is possible for one or more cores of the blockage  202  to become stuck within the catheter tube  102 . In such a scenario, various devices can be used to clear the stuck cores. 
     For example, referring now to  FIG. 6 , an example syringe  602  is coupled to the proximal end  106  of the catheter  100  using, for example, a suction line fitting or Luer-lock style connection. In this embodiment, the syringe  602  can be a typical 60 cc syringe that is used to deliver air into the catheter tube  102  during coring of the blockage  202  to dislodge and/or remove portions of the blockage  202  that are in the catheter tube  102 . 
     In this instance, a plunger of the syringe  602  is actuated to displace air within the syringe  602  into and through the catheter tube  102 . This air can be used to dislodge obstructions within the tube. Other configurations are possible. For example, other types of fluids, such as a jet spray of water, could be used to help clear the tube or break up food. 
     In other instances, different devices can be used to clear the catheter  100 . For example, referring now to  FIGS. 7-8 , a stylet  700  is shown that is sized to fit through the hollow interior of the catheter tube  102 . Generally, the stylet  700  can be used to perform various functions. 
     For example, the stylet  700  can be used to stiffen the catheter  100  during delivery to the blockage  202 . Further, the stylet  700  can be introduced through the catheter tube  102  to clear the catheter tube  102  when one or more cores get stuck, performing a function of a pusher rod. Finally, the stylet  700  can also be used to pierce the blockage  202  to start a nidus for coring and suctioning. In some examples, the stylet  700  can also be solid or hollow. 
     In this example, the stylet  700  further includes a stylet knob  702  that is configured to be engaged with the proximal end  106  of the catheter  100 . The proximal end  106  can be configured to include a Luer taper that allows the proximal end  106  to engage the stylet knob  702  of the stylet  700 . Other coupling arrangements, such as a threaded engagement, can be used. 
     As shown in  FIG. 8 , the stylet knob  702  is coupled to the proximal end  106  of the catheter tube  102 . In this configuration, the catheter  100  can be delivered to the desired location within the esophagus  204 . At that time, the stylet knob  702  can be disengaged from the proximal end  106  to free the stylet  700  for movement. This movement can include the caregiver pushing the stylet  700  into and out of the catheter tube  102  to generally disrupt the blockage  202  and/or removal of the stylet  700  completely from the catheter tube  102 . 
     When the stylet  700  is removed from the catheter tube  102 , the vacuum line  220  can be connected to the proximal end  106  of the catheter tube  102  for suctioning, as described previously. 
     In this example shown in  FIG. 8 , the catheter tube  102  is approximately 80.5 inches in length and the stylet  700  is approximately 84 inches in length, although many different lengths can be provided such as, for example, shorter lengths for children and longer lengths for adults or to accommodate different length endoscopes, bronchoscopes or colonoscopes. The example catheter tube  102  has an outer diameter of 0.135 inches and an inner diameter of 0.115 inches. The stylet  700  has an outer diameter of 0.105 inches. Other sizes can be used. 
     In other embodiments, the catheter tube  102  can be variable in length and diameter. For example, another embodiment of the catheter tube  102  measures 0.093 inches in outer diameter and 0.082 for the inner diameter, allowing for easy introduction and sliding within the working channel of any endoscope. The catheter tube  102  is long enough to extend through an endoscope, at least 120 cm in length but can be longer. 
     The stylet  700  can vary in diameter, but in the preferred embodiment measures 0.070 inches in outer diameter to allow easy introduction and sliding within the catheter tube  102 , and is slightly longer than the catheter tube  102  to allow the stylet  700  to extend beyond the distal end  104  of the catheter tube  102  to clear the catheter tube  102  and extend further into the blockage  202 , if necessary. 
     The catheter tube  102  can be made from a thin-walled extruded tube sized to fit the working channel (biopsy channel) of any commercially available endoscope. One example material is Pebax 7233 SA. Another possible material would be an extrusion grade of PETG. Other possibilities would be Polyamide or extrusion grade Nylon or Delrin, such as Nylon 10 or Nylon 12. 
     The stylet  700  could be made of the same or similar material. For example, the catheter tube  102  and the stylet  700  can be made of the same material to allow the stylet  700  to fit within the catheter tube  102  while minimizing friction. However, other materials and different materials for each can be used. 
     The above materials would clear food, but would not seriously damage the walls of the esophagus should they inadvertently contact the walls of the esophagus. 
     Referring now to  FIGS. 9-17 , another example device  900  is shown. The device  900  includes the catheter tube  102  with a suction port  902  at the proximal end  106  and with the distal end  104  that is designed (e.g., beveled) to be advanced through the biopsy channel of any commercial endoscope and that can accommodate the stylet  700  to clear food that sticks in the catheter tube  102  after removal from the esophagus. 
     As shown in  FIG. 9 , the catheter tube  102  is designed to fit through the biopsy channel of an endoscope positioned within the esophagus to reach a food blockage, but can also be advanced adjacent to an endoscope and can also be advanced orally without the aid of an endoscope. The catheter tube  102  is also bendable and maneuverable as the endoscope bends and maneuvers, yet is rigid enough to withstand kinking. 
     In this example (see  FIGS. 9 and 15 ), there is a Y-fitting  904  wherein one arm  906  of the Y is attached to and forms the suction port  902 , and another arm  908  of the Y accommodates the stylet  700 . 
     There is also a compression seal  910 , or rubber stopper, at the proximal end of the arm  908  that accommodates the stylet  700 , so that any air escaping the proximal end is minimized when the stylet  700  is in the catheter tube  102 , so that suction and stylet clearance of the vacuum tube can occur simultaneously. When the compression seal  910  is loosened, the stylet  700  can be easily advanced into and out of the catheter tube  102  using a handle  912  of the stylet  700 . The compression seal  910  can also secure the stylet  700  in any location along the shaft of the catheter tube  102 . 
     In this example, a cap  914  is threaded onto the proximal end  916  of the arm  908  to retain the compression seal  910  in place. Upon removal of the stylet  700  from the catheter tube  102 , the compression seal  910  is configured, in some embodiments, to close the proximal end  916  so that suction can be performed through the catheter tube  102  and the suction port  902 . 
     In the example shown, the catheter tube  102  can work with the stylet  700  completely removed; the stylet  700  can also be introduced as needed, and advanced any distance in the catheter tube  102 . 
     As with previous embodiments, the distal end  104  of the catheter tube  102  can disrupt food, core food, shave food and suction food. The catheter tube  102  wall could be thin and rigid to better accommodate a larger lumen of the tube. The stylet  700  can help support the catheter tube  102  to help prevent kinking if necessary. Thus the stylet  700  can both help clear the suction tube and act as a stylet to stiffen the catheter tube  102 . 
     Many alternative designs are possible. For example, in another design shown in  FIGS. 18-19 , a stylet  1800  could have a spline shape  1802  with splines  1804  formed along the stylet to better accommodate suction when the stylet in is the catheter tube. In other words, spaces  1806  are formed between the splines  1804  to allow suction to be provided through the catheter tube  102  even with the stylet  1800  in place within the catheter tube  102 . Other configurations are possible. 
     Referring now to  FIGS. 20-21 , another example of a stylet  2000  is shown. In this example, the stylet  2000  is a wire  2002  with a piston  2004  positioned at an end  2006  thereof. The piston  2004  can be automatically (and/or manually) actuated intermittently or at regularly intervals (such as by a motor) to drive the stylet  2000  through the catheter tube  102  to engage the blockage in the esophagus. Other configurations are possible. 
     Referring now to  FIGS. 22-24 , another example device  2200  is shown. The device  2200  is similar to the embodiment of  FIGS. 20-21 , except that the device  2200  does not necessarily need suction. Instead, the device  2200  includes a handle  2202  and a tube  2204 . The handle  2202  includes an actuator member  2206  that can be moved (e.g., by the caregiver&#39;s finger or thumb) in a direction  2208  in or out. 
     The actuator member  2206  is coupled to a wire  2210  that runs through the tube  2204  to an ejector piston  2402 . The ejector piston  2402  is positioned within a cavity  2404  formed in a distal end  2406  of the tube  2204 . The distal end  2406  of the tube  2204  forms an opening  2408  sized to core or otherwise carve the obstruction as the caregiver moves the handle  2202  and the tube  2204  attached thereto. This is accomplished, for example, by the pieces of the obstruction being carved by the distal end  2406  of the tube  2204  and received in the cavity  2404 . 
     As the cavity  2404  is filled, the caregiver can move the actuator member  2206  to cause the ejector piston  2402  to be moved by the wire  2210  through the cavity  2404  towards the distal end  2406  of the tube  2204  to eject food out of the opening  2408 . This process can be done multiple times until the obstruction is cleared. The actuator member  2206  can be biased to return to the retracted position and/or simply be moved in the opposite direction  2208  by the caregiver&#39;s finger to return the ejector piston  2402  to the retracted position 
     In some examples, the distal end  2406  of the tube  2204  can be configured to more easily core the obstruction. For example, the distal end can be thinned or serrated so as to be sharper. In other examples, additional features, such as a stainless steel tip, can be added to the distal end  2406  of this (or any other embodiment disclosed herein) to enhance the coring impact of the device  2200 . 
     In some examples, the inner surface of the tubes can be configured to more easily allow cores of the obstruction to pass therethrough. For example, the inner surface of a tube can be coated with a low friction or lubricious material to encourage passage and discourage clumping of the cores. Examples of such low friction materials include, without limitation, Poly vinyl pyrolidone and Hyaluronic acid. Such materials can be typically bonded using heat or ultraviolet light. The external surface of the catheter  102  can optionally also be coated with low friction materials to enable passage through the endoscope. Other mechanisms, such as differing tapers and/or channeling of the inner surface, can also be used. 
     The examples described above refer to impactions in the esophagus. However, many other similar impactions can be addressed using the systems and methods described herein. 
     For example, a person can choke while eating, and food can get aspirated and lodge in the trachea, or can also lodge in the lung, specifically any portion of the bronchial tree. Mucus can also become trapped anywhere in the bronchial tree, causing mucus plugging. When this occurs, one or more of the embodiments described herein can be used to core and suction said food or mucus, by placing the device through the working channel of a flexible or rigid bronchoscope as opposed to an endoscope. 
     One or more of the embodiments described herein can also be used to core, suction and remove trapped blood or blood clots anywhere in the GI tract, specifically the esophagus, stomach, small intestine or large intestine. 
     One or more of the embodiments described herein can also be used to core, suction and remove trapped food, blood or blood clots, or mucus or mucus plugs, anywhere in the pulmonary organ system, i.e., the trachea or lung i.e. anywhere in the bronchial tree. 
     One or more of the embodiments described herein can also be used to core and remove blood or blood clots, or atheroma or atheromatous plaque anywhere in the vasculature system, i.e. great arteries or veins, or peripheral vasculature i.e. the peripheral arteries or veins. To core harder materials such as calcified plaque, a stainless steel tip and be attached to the end of the suction catheter. 
     One or more of the embodiments described herein can also be used to core and remove blood or blood clots, or atheroma or atheromatous plaque anywhere in the heart or coronary arteries. To core harder materials such as calcified plaque, a stainless steel tip can be attached to the end of the suction catheter. 
     In another example, One or more of the embodiments described herein can be used to core and suction kidney stones from the urinary system, specifically the ureters, bladder and kidneys. To core harder materials such as calcified, struvite, oxalate or uric acid kidney stones a stainless steel tip can be attached to the end of the suction catheter. 
     In yet another example, one or more of the embodiments described herein can be used to core and remove gallstones or tumors lodged in the biliary tree (common bile duct or peripheral ducts). Harder materials can be cored by attaching a stainless steel tip to the end of the suction catheter. 
     Although various embodiments are described herein, the embodiments are only examples and should not be construed as limiting.