CROSS REFERENCE TO RELATED APPLICATIONSThis application is a continuation of U.S. patent application Ser. No. 13/783,250, filed Mar. 2, 2013, which is a divisional of U.S. patent application Ser. No. 11/675,525 filed Feb. 15, 2007, now U.S. Pat. No. 8,414,561 which issued on Apr. 9, 2013 which claims the benefit of U.S. provisional application No. 60/821,333, filed Aug. 3, 2006, now expired, the contents of which are incorporated by reference herein in their entirety.
BACKGROUND OF THE INVENTIONThe invention generally relates to removing ingested material from a stomach of a patient, and the primary intended fields of the invention are facilitating weight loss and preventing weight gain.
BRIEF SUMMARY OF THE INVENTIONIn one aspect of the invention, food that has been ingested is removed from the patient's stomach via a gastrostomy tube using a siphon action. In another aspect of the invention, food that has been ingested is removed from the patient's stomach via a gastrostomy tube, and the removal of food is facilitated by infusing fluid into the patient's stomach via the gastrostomy tube. In another aspect of the invention, matter that has been ingested is removed from the patient's stomach via a gastrostomy tube, and stomach acid is separated from the removed matter and returned to the patient's stomach. In another aspect of the invention, matter that has been ingested is removed from the patient's stomach via a gastrostomy tube, and the system is configured to disable itself from further use after the occurrence of a triggering event (e.g., the passage of time or a predetermined number of uses).
BRIEF DESCRIPTION OF THE DRAWINGSFIG. 1 is a schematic representation of an embodiment of the invention for removing ingested material from a patient's stomach.
FIG. 2 is a schematic representation of a first embodiment for implementing the system shown inFIG. 1.
FIG. 3 is a schematic representation of a second embodiment for implementing the system shown inFIG. 1.
FIG. 4 shows a side view of a third embodiment for implementing the system depicted inFIG. 1.
FIG. 5A shows an isometric view of theFIG. 4 embodiment.
FIG. 5B shows a front view of internal components of theFIG. 4 embodiment.
FIG. 5C shows a back view of internal components of theFIG. 4 embodiment.
FIG. 6A shows an isometric view of another embodiment for implementing the system depicted inFIG. 1.
FIG. 6B shows a front view of internal components of theFIG. 6A embodiment.
FIG. 7A schematically shows an embodiment of a system for removing ingested material from a stomach, filtering select gastric contents, and returning filtered fluid to the stomach.
FIG. 7B schematically shows an embodiment of a system for removing ingested material from a stomach, filtering select gastric contents, and returning filtered fluid and water to the stomach.
FIG. 8A shows a patient with a skin connector coupled with a gastrostomy tube that is inserted into the stomach.
FIG. 8B shows a view of the skin connector prior to mating with a tube connector.
FIG. 8C shows a view of the skin connector mated with a tube connector.
FIGS. 9A,9B, and9C show side, top, and isometric views of a skin connector valve assembly for the embodiment shown inFIGS. 8A-8C.
FIGS. 10A,10B, and10C show side, top, and isometric views of an assembled flush skin connector for the embodiment shown inFIGS. 8A-8C.
FIGS. 11A,11B, and11C show side, top, and isometric views of a skin connector flange assembly for the embodiment shown inFIGS. 8A-8C.
FIG. 12 is an exploded view of the rotational valve assembly for the embodiment shown inFIGS. 8A-8C.
FIG. 13A shows a bottom view of a tube connector assembly for the embodiment shown inFIGS. 8A-8C.
FIG. 13B shows a side view of a tube connector assembly for the embodiment shown inFIGS. 8A-8C.
FIGS. 14A and 14B show the tube connector connected to the skin connector of the embodiment shown inFIGS. 8A-8C, in the closed and opened positions, respectively.
FIG. 15 shows the embodiment shown inFIGS. 8A-8C being used by a patient.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTSThis application discloses methods and apparatuses for removing material from a patient. In the exemplary embodiment disclosed herein, the methods and apparatuses are used for removing ingested material from a patient's stomach in patients that have been fitted with a gastrostomy tube. Examples of suitable gastrostomy tubes are described in U.S. Patent Application Publication Nos. US 2004/0220516, US 2005/0277900 and US 2005/0283130, each of which is incorporated herein by reference. Additional gastrostomy tubes are described in U.S.Provisional Patent Application 60/806,556, which is also incorporated herein by reference.
The primary contemplated use for the methods and apparatuses described herein is achieving weight loss in obese or overweight people. Although the exemplary embodiments are described herein in the context of removing ingested material from a patient's stomach, the methods and apparatus can also be used for removal of a variety of fluids from a patient (with, when necessary, appropriate modifications that will be apparent to persons skilled in the relevant arts).
FIG. 1 shows a patient10 that is fitted with a gastrostomy tube with a system for removing ingested material from a stomach. An example of such agastrostomy tube45 is shown inFIG. 8A. Thegastrostomy tube45 interfaces with the outside world viaconnection14, so the system communicates with thegastrostomy tube45 through that connection. The system preferably includes anassembly16 for infusing fluid into the stomach through theconnection14 in a manner permitting the fluid to mix with the ingested material or, for use in priming the system when desired, and adrain line18 for draining content of the stomach received from theconnection14.
Thedrain line18 may be in communication with theassembly16, as shown. In alternative embodiments (not shown), thedrain line18 may be implemented independent of theassembly16. For example, one line may be used to drain content of the stomach through theconnection14 and another line may infuse the fluid into the stomach through the connection. The system preferably includes apatient line20 in communication with theassembly16 and theconnection14 to thepatient10, and thepatient line20 preferably has a suitable connector at its upper end that mates with theconnection14. In alternative embodiments (not shown), theassembly16 may be coupled directly to theexternal gastrostomy connection14 without using an intermediate patient line. Theassembly16 may include a fluid source and may optionally include a valve arrangement and/or one or more pumps as described in more detail below.
In operation, the system is connected up to theconnection14 to remove the contents of the stomach via the connection. In some embodiments, the removal may be accomplished by pumping the stomach contents out via theconnection14. In alternative embodiments, this removal is accomplished by setting up a siphon system so that the contents of the stomach can be siphoned out of the patient's stomach.
In siphon-based systems, thedrain line18 preferably has a length in excess of25 cm in order to create a pressure differential that is sufficient to form an effective, efficient siphon that can gently and passively drain content from the stomach. However, in alternative embodiments, thedrain line18 can be of a length less than25 cm. Note that when the patient is standing, the overall siphon system is measured from the lowest point in the tube or line that is inserted into the stomach to the end of thedrain line18. Optionally, the siphon system may be designed to be long enough to run from the stomach of a standing patient to a position proximate to a floor-based disposal arrangement, such as a toilet or waste container. The drain line may include a siphon tube made from flat, collapsible tubing or other flexible tubing. Silicon is a suitable material for thepatient line20 and thedrain line18. However, in alternative embodiments, thepatient line20 can be made from any material known and used in the art of tubes or any material that could be used to impart the necessary function of thepatient line20.
In some situations (e.g., when the patient has drank a significant amount of liquids), an effective siphon effect can be achieved without infusing any liquids into the patient's stomach. In other situations, however, it may be necessary to add additional fluid into the patient's stomach to help start up the siphoning, so that the ingested material can be effectively removed from the patient's stomach. This may be done by having the patient drink additional fluids or by infusing additional fluid into the stomach through theconnection14.
In many cases, a single siphoning operation will be insufficient to remove the desired amount of ingested material from the patient's stomach. In those cases, it is desirable to introduce additional liquid into the stomach so that one or more additional siphoning operations can be done. A preferred approach for introducing additional liquid into the stomach is by infusing the liquid into the stomach through theconnection14. For example, after eating a meal and drinking liquids, the subject may attach the device to theconnection14, and siphon out a large portion of the stomach contents (e.g., fluid with solid particulate, pieces, and/or chunks of food). For a typical meal, the volume of this initial siphoning operation may be on the order of750 cc, but that number will of course vary based on the volume and characteristics of the ingested meal. Once the siphon effect stops, the subject infuses water back through theconnection14 into the stomach and then initiates another siphoning operation to remove the infused water, which will carry out additional solid food particles, pieces and/or chunks. The infusing and siphoning steps may then be repeated until the desired amount of ingested material is removed from the stomach. An example of a suitable volume for infusing into the stomach during the infusing step is 180 cc, although any other volume may be used.
Note that the methods described herein are preferably used to remove a significant portion of the food that the patient has ingested (e.g., between 30 and 60%, and more preferably between 40 and 50%, of the ingested food). Removing all the food that was ingested by the patient is not preferred and will usually be impractical. Examples of systems that implement both the removal of ingested material and the infusion of fluids are described below.
FIG. 2 schematically shows a first embodiment of a system for alternately removing ingested material from a stomach and infusing fluid into the stomach. The fluid may be any biocompatible fluid such as water or saline, and may optionally include one or more nutrients and/or medications. As shown, theassembly16 includes afluid source22 and a valve arrangement24 in communication with thefluid source22, thedrain line18, and thepatient line20. The valve arrangement24 may include one or more valves and any type of valve, such as, but not limited to, check valves, blade occluder and diverter valves. For example, the valve arrangement24 may be implemented using a single 3-way valve with two operating positions—one position that opens a path between thepatient line20 and thedrain line18, and another position that opens a path between thefluid source22 and thepatient line20. Alternatively, the valve arrangement24 may be implemented using two valves—a first valve used to open a path between thepatient line20 and thedrain line18 and a second check valve used to open a path between thefluid source22 and thepatient line20 when fluid is pumped from thefluid source22 into the patient's stomach via connection14 (shown inFIG. 1). In operation, the first valve is opened to drain the contents of the stomach. The first valve is then closed and fluid is pumped from thefluid source22 to thepatient line20. Optionally, the first valve may be closed automatically by the fluid when the fluid is pumped from thefluid source22. The first valve may then be re-opened to drain content of the stomach when fluid is no longer pumped to thepatient line20.
Other embodiments may include a plurality of valves, such as shown inFIG. 3.FIG. 3 schematically shows anassembly16 having a check valve, valve A, in communication with thefluid source22 and also with two valves, valve B and valve F. Valve B is in communication with a check valve, valve C, which is in communication with the connection14 (shown inFIG. 1) via thepatient line20. Valve F is in communication with a check valve, valve E, which is in communication with thedrain line18. Another valve, valve D is in communication with thepatient line20 and thedrain line18. Valve B and valve F may be coupled, such that valve B is opened when valve F is closed, and valve F is opened when valve B is closed. In operation, valve B is opened while valve F is closed. Valve D may then be opened to drain the contents of the stomach received from thepatient line20. Optionally, the system may be configured so that as fluid is pumped through valve B and valve C, the movement of the fluid closes valve D and permits the fluid to flow into the stomach through thepatient line20. When fluid is no longer pumped through valves B and C, valve D may be activated automatically or manually to re-open to drain content of the stomach. When finished removing content from the stomach, valve D is closed and valve B is closed, which in turn opens valve F. The fluid may then be pumped through valve A, valve F and valve E to thedrain line18 in order to clean the drain line after use.
Variations on theassembly16 shown inFIG. 3 may be implemented using one or more pumps in communication with the valve arrangement24, thefluid source22 and/or thedrain line18. For example, a pump may be coupled between thefluid source22 and thepatient line20 with a check valve in communication with thefluid source22 and the pump and another check valve in communication with the pump and thepatient line20 to facilitate fluid flow to the connection14 (shown inFIG. 1). A pump may be coupled between thepatient line20 and thedrain line18 with a check valve in communication with thepatient line20 and the pump and another check valve in communication with the pump and thedrain line18. A pump may also be provided by the squeezing of a hand, e.g., squeezing the fluid source. A combination of two or more pumps may be used, to facilitate fluid flow to thepatient line20, to thedrain line18, or both. For example, during operation, if the system becomes clogged with content of the stomach such that the draining and/or infusing is not functioning properly, a pump may be provided to clear the obstruction in thepatient line20 and/or thedrain line18. Various types of pumps may also be used, such as, but not limited to, a diaphragm pump, a spring loaded piston pump, a syringe pump, a peristaltic pump, a flexible vein pump, a pneumatically actuated pump or a combination thereof. The pump(s) may be removable from the system such that a pump is only provided when necessary.
Referring now toFIGS. 2 and 3, a removable syringe may be provided at anauxiliary port25 to provide suction for removing clogs from thepatient line20 and/ordrain line18. Although various configurations have been discussed for the valves and pumps with respect toFIGS. 2 and 3, it will be apparent to those skilled in the art that any number, kind, and/or configuration of valves and pumps may be used.
FIGS.4 and5A-5C show an embodiment of a system for removing ingested material from the stomach. In this embodiment, the system includes thefluid source22, thedrain line18, and thepatient line20 and also includes anactuation handle26 for opening and closing a path between thepatient line20 and thedrain line18 and for opening and closing a path between thefluid source22 and thepatient line20. In operation, the actuation handle26 may toggle theassembly16 between two modes, a drain mode and an infusion mode. For example, in the drain mode, the actuation handle26 may be in its original or un-actuated position which may cause the path between thepatient line20 and thedrain line18 to be opened and the path between thefluid source22 and thepatient line20 to be closed, thus permitting content of the stomach to be drained. When theactuation handle26 is squeezed or actuated, the actuation handle26 causes the path between thepatient line20 and thedrain line18 to be closed and the path between thefluid source22 and thepatient line20 to be opened. The actuation handle26 causes thefluid source22 to be squeezed or pumped, forcing the fluid out of thefluid source22, thus allowing fluid to flow into the stomach in the infusion mode. For example, a user may squeeze theactuation handle26 andfluid source22 by hand. When theactuation handle26 is released, theactuation handle26 is returned to its original position, e.g., by a spring force, such as an extension spring, causing the path between thepatient line20 and thedrain line18 to be re-opened and the path between thefluid source22 and thepatient line20 to be re-closed. The actuation handle26 may cause the various paths to be opened or closed using any of a variety of approaches that will be apparent to persons skilled in the relevant arts, e.g. by pressing or pinching the various fluid lines or actuating valves.
Still referring to FIGS.4 and5A-5C, the system may also include apatient line cap28 and a patient port plug30 for when the system is not in use and removed from the patient. For example, theassembly16 may be removed from thepatient line20 and thepatient line cap28 may be used to terminate thepatient line20. Similarly, thepatient port plug30 may be used to plug the opening where thepatient line20 couples to theassembly16.
Theassembly16 may also include a rinseslide32 for opening and closing a path between thefluid source22 and thedrain line18. After the system is used to infuse fluid into the stomach and drain contents out of the stomach, thefluid source22 may be used to rinse out or clean thepatient line20, thedrain line18 or both. Upon completion of use, the actuation handle26 may be squeezed with thefluid source22 to cause fluid to flow through and clean thepatient line20. Once thepatient line20 is clear, thepatient line20 may be clamped while still holding theactuation handle26 and thepatient line20 may be disconnected from theassembly16. The actuation handle26 may then be released. In order to clean thedrain line18, the rinseslide32 may be activated, allowing fluid to flow from thefluid source22 down the drain line. When the rinse slide is activated, both valves open and since the drain line is lower than the fluid source, the fluid flows out of thedrain line18. The actuation handle26 may then be squeezed with thefluid source22, causing fluid to be pumped out of thefluid source22 and through thedrain line18, cleaning thedrain line18.
Referring now toFIG. 4, optionally, the system may include anattachment mechanism34 such as a belt clip, for attaching theassembly16 to the patient during use of the system. Now referring to FIGS.4 and5A-5C, theattachment mechanism34 may be coupled to theassembly16 at anattachment location36. Thefluid source22 may be coupled to theassembly16 at anattachment assembly38.
FIGS. 6A and 6B depict analternative assembly16′ that may be used in place of theassembly16 depicted in FIGS.4 and5A-5C. In this embodiment anactuation lever44 alternately either (a) opens a path between thepatient line20 and thedrain line18 or (b) closes the path between the patient line and the drain line. Referring now toFIG. 6B, when thelever44 is actuated in this embodiment, it causes the path between thepatient line20 and thedrain line18 to be clamped byclamp49 and the path between thefluid source22 and thepatient line20 to be opened. When thefluid source22 is squeezed while thelever44 is in an actuated position, fluid from thefluid source22 will flow through a check valve, into the patient line and into the stomach. When thelever44 is in a non-actuated position, the path between thepatient line20 anddrain line18 is open. Upon squeezing thefluid source22 in a non-actuated position, water flows from thefluid source22 through thedrain line18 and causes a rinsing effect, which obviates the need for the separate rinse slide. In the illustrated embodiment, theactuation lever44 may cause the paths to be closed/opened byclamp49 pressing or pinching on the tubing lines. However, persons skilled in the relevant arts will recognize that alternative approaches for opening and closing the various fluid flow paths may be substituted by making appropriate modifications.
Since water bottles may have varied thread designs which would not ordinarily mate with conventional female fittings, a universalfluid source receptacle46 may optionally be implemented to accept any water bottle neck, and to lock around the bottle neck flange. Upon actuation the receptacle releases the flange on the fluid source. This feature may also be implemented in the other embodiments described herein.
The system is preferably connected to a gastrostomy tube that has previously been installed in a patient (e.g., through the patient's abdominal wall), with a port that extends out of the patient's body. Preferably, the port is relatively flush with the surface of the patient's abdomen and has a connector that mates with a mating connector of the system. A variety of ways to implement such a flush mount connection interface can be readily envisioned.
FIGS. 8-15 depict one preferred implementation of a flush mount connection interface. One part of the interface is the “skin connector”60 (shown inFIGS. 9-12) which is an implementation of theconnection14 discussed above in connection withFIG. 1, and is affixed to the patient and thegastrostomy tube45 that resides inside the patient's stomach. This embodiment of theskin connecter60 includes a rotational valve assembly that controls opening and closing of the pathway into the stomach, as shown inFIGS. 14A-14B. The other part of the interface is the “tube connector”65, also shown inFIGS. 14A-14B, which is positioned at the upper end of thepatient line20 and is designed to mate with the skin-connector60 with a fluid-tight interface.
FIGS. 9-11 depict arotational valve assembly50 that is assembled inside askin flange55 to create a flushmount skin connector60, andFIG. 12 is an exploded view of therotational valve assembly50. Three of thevalve assembly components81,82,83 have a thru-hole biased to one quadrant, arranged so that the valve is opened when the thru-holes are aligned and so that the valve is closed when the thru-holes are not aligned. In the preferred embodiment, the size for the entire valve assembly is about 4 cm in diameter, and the size for the thru-holes is about 6-8 mm in diameter. However, in other embodiments, the valve assembly can be proportionally different size, either larger or smaller. Thevalve assembly50 is preferably constructed oftop platform81 and abottom platform83, with a layer ofelastomer82 that is attached to thetop platform81 and sandwiched between the top platform and thebottom platform83 with a force that is high enough to prevent leaks, yet low enough to permit rotation of theelastomer82 with respect to thebottom platform83. The elastomer is attached to the top platform using any adhesive that would attach the silicon to the plastic, however, in one embodiment, a primer and a fast curing adhesive is used. Thetop platform81 is preferably made of a lubricious plastic for example, acetyl, and in some embodiments, DELRIN™, TEFLON™, polyethylene, etc, can be used, and thebottom platform83 is preferably made of ABS or another hard plastic. However, in alternative embodiments, those components may be made of other materials that provide similar functionality. Atop retaining ring80 is configured to attach to thebottom platform83 to retain thetop platform81 and themiddle layer82 while allowing those two layers to rotate with respect to thebottom platform83. Attaching can be in the form of snap fitting, welding, gluing or any other method of attachment. Thetop retaining ring80 is preferably also made of ABS or another hard plastic. In the illustrated embodiment, as best seen inFIGS. 9-11, thevalve assembly50 hasprotrusions53 at its bottom that allows it to fasten torecesses56 in theskin flange55 to form theskin connector60. The top face of the valve assembly preferably has a structure (e.g., the cut-outs52) for mating with a corresponding surface on thetube connector65. Thevalve assembly50 can be disassembled from theskin connector60 by pushing theprotrusions53 at its bottom out of therecesses56 in theskin flange55. With significant force, manually or with a tool directed at the bottom of therecesses56, thebarbed protrusions53 can be freed from therecesses56 inskin flange55 and thevalve assembly50 can be removed.
Removal of the valve may be required when a course of treatment is finished or in connection with valve replacement due to wear, scheduled maintenance, cleanliness, or length adjustment. Using a removable valve permits adjustment of the length of the gastrostomy tube (e.g. after patient weight loss) to compensate for a shortened stoma tract. After the valve is removed, the tube is cut to a shorter length, and then the valve is replaced, advantageously avoiding the need to replace the gastrostomy tube.
Due toprotrusions66 on the contacting surface of thetube connector65 being configured to mate and mechanically couple with the cut-outs52 on thevalve assembly50 at a rotational distance of approximately 120.degree. from the “open” position ofvalve assembly50, fluid will not leak out ofvalve assembly50 duringtube connector65 removal (i.e.disc68 is always covering the passageway ofskin connector60 prior to removal.)
For a gastrostomy tube designed to aspirate food from a full stomach (i.e. larger diameter to accommodate food particles,) the fluid pressure may be higher than traditional feeding tubes, and the illustrated valve embodiments can withstand such higher pressures without leaking. The illustrated valve embodiments are also designed to provide a large, uniform lumen from the tube through the valve. The rotational gasket configuration allows sealing of the tube without restricting the lumen dimension when the valve is in the “open” position, thereby minimizing the probability of tube clogging during food aspiration.
FIGS. 13A and 13B depict atube connector65 that is connected at the upper end of thepatient line20. Thetube connector65 is designed to mate with the skin connector, andprotrusions66 on the contacting surface of thetube connector65 are configured to mate with the cut-outs52 on the valve assembly50 (both shown inFIG. 9B). The body of thetube connector65 is preferably constructed of a hard plastic such as ABS. The contacting surface of thetube connector65 is preferably implemented using adisc68 made of an elastomeric material such as silicone, with a biased thru-hole67 that is dimensioned and positioned to match the thru-hole of the skin connector. In the illustrated embodiment, thetube connector65 has a ridge71 around the perimeter of its contacting surface that is configured to fit into a mating surface of the skin connector (i.e., the valley61 around the perimeter of theskin connector60, shown inFIG. 10C). The outer surface of the illustrated tube connector also has ahandle69 for grasping by the user and a barbedhollow protrusion70 that is in fluid communication with the thru-hole on the contacting surface for fastening to the patient line tubing.
Referring now to FIGS.10C and12-14, when thetube connector65 and theskin connector60 are not mated, thevalve assembly50 on theskin connector60 is in a “closed” position, with the thru-hole51 in thetop platform81 and themiddle layer82 oriented out of phase with respect to the thru-hole54 in thebottom platform83. To connect thetube connector65 and theskin connector60, the thru-hole67 of the tube connector is aligned with the thru-hole51 in thetop platform81 of thevalve assembly50. Thetube connector65 is then turned by grasping thehandle69 and turning it clockwise. When this happens, the biased thru-hole51 in thetop platform81 and themiddle layer82 and the thru-hole67 in thetube connector65 will all rotate together into alignment with the thru-hole54 in thebottom platform83 of thevalve assembly50, thereby opening a passage to the gastrostomy tube. Rotating thetube connector65 clockwise also engages mating features66 on the tube connector with corresponding cut-outs52 on the valve assembly50 (shown inFIG. 9B) to lock thetube connector65 to the skin connector.
After the passage is open, removal of ingested material from the patient's stomach is performed, as described above (optionally in alternation with the infusing of liquids into the patient's stomach). Subsequently, the patient or practitioner rotates thetube connector65 counterclockwise, which causes the thru-hole67, the biased thru-hole51 in thetop platform81, and themiddle layer82 to all rotate together away from the thru-hole54 in thebottom platform83 of thevalve assembly50, to the position shown inFIG. 14A, thereby closing the valve in theskin connector60. Thetube connector65 can then be pulled away from theskin connector60.
Referring now toFIGS. 10-11, theskin connector60 is preferably constructed with anouter skirt58 composed of a soft, compliant material (e.g. elastomer, foam, etc.) that tapers the fully assembled low-profile skin-port towards the skin to provide a more aesthetic appearance, to prevent theskin connector60 from catching on the user's clothing, and to serve as a bumper against applied stresses. In alternative embodiments, theskin connector60 andtube connector65 can be configured in various other forms and/or can use different materials to optimize various characteristics. For example, both theskin connector60 andtube connector65 can be made with an oblong shape. The mating features and turning of the valve can be actuated by alternate means that will be apparent to persons skilled in the relevant arts, including but not limited to thumbwheel mechanisms, scissor mechanisms, etc.
One potential side-effect of aspirating food from the stomach is lowering of electrolytes, such as potassium. The removal of hydrochloric acid (HCl) from the stomach along with food particles can cause the human body to excrete potassium to maintain a charge balance, and excretion of too much potassium can cause hypokalemia. One method for preventing hypokalemia is to give the patient potassium supplements and a proton pump inhibitor.
Another method for preventing hypokalemia is to selectively remove HCl from the extracted material, and return it to the patient's stomach, in order to prevent electrolyte imbalance and obviate the need for additional therapeutics. To achieve acid return to the stomach, the device may be configured with one or more semi-permeable filters that selectively screen out waste product and retain HCl for return to the stomach. Examples of suitable filters include mechanical filters, chemical filters, ionic membranes (e.g. anionic exchange membrane, cationic exchange membrane, bipolar membrane), and electrochemical filtrations systems (or a combination of the above).
One way to implement food evacuation with the return of acid to the stomach is by using two filters in series. The first filter, or pre-filter, separates food particles from the fluid. Examples of suitable filters for performing this function include mechanical filters like standard glass-fiber or cellulose filters that selectively remove solids above a specified particle size, leaving “waste” fluid. A suitable porosity for such a filter is 2.5 .mu.m porosity. The second filter removes hydrochloric acid from the pre-filtered fluid. Examples of suitable filters for performing this function include semi-permeable membranes, or an anionic exchange membrane (e.g. NEOSEPTA™, Tokuyama, Japan).
FIG. 7A depicts a first embodiment for returning acid to the stomach. A siphon effect or a pump is used to force evacuated stomach contents through the pre-filter110 and into onecompartment122 of adual chamber container120, which is separated from theother compartment126 by ananionic exchange membrane124. Thesecond chamber126 contains deionized water. The difference in ionic concentration between the dual chambers of thecell120 will drive a diffusion dialysis process to occur in which the Cl− and H+ ions from hydrochloric acid selectively transfer across themembrane124 into the water filledchamber126. The waste fluid can then be released to exit to the toilet, and apump130 can then be actuated to force the HCl and water solution back into the patient's stomach.FIG. 7B depicts an alternative embodiment that is similar to theFIG. 7A embodiment, but adds a separate water infusion subsystem140 to allow the subject to continue to flush and siphon the stomach while the diffusion dialysis process is occurring. More complex filtration system can also be used, including but not limited to electrodialysis, or an anode and a cathode to separate charged ions in an electrophoresis like fluid suspension. The electrofiltration process could potentially decrease the time to remove the HCl from the waste product.
Repeated removal of food from a patient's stomach to achieve weight loss requires close medical supervision to avoid complications (e.g., a drop in electrolyte levels). It may therefore be desirable for the physician to ensure that the patient returns for follow-up and blood testing to avoid improper use of the device, or at a minimum have data that reveals the patient compliance with proper use of the system. A shut-off mechanism may be built into the system to ensure that the patient returns for such follow-up. The shut-off mechanism preferably operates based on some measurement of usage such as the passage of time (e.g., to disable the device after one month), the number of cycles of use (e.g., to disable the device after 90 uses), or the volume of extracted matter (e.g., to disable the device after 50 liters of material have been removed).
The measurement of usage may be implemented by mechanical or electrical means, as will be appreciated by persons skilled in the relevant arts (e.g., using a mechanical counter such as a multi-decade geared mechanism that is incremented using a cam-actuated sprocket, or an electrical counter that is incremented by a suitable sensor). Suitable events that can be used to increment the count include, but are not limited to, the connection of a water bottle to the system, the connection of the tube connector to the skin connector, etc. The shut-off mechanism may also be implemented by mechanical or electrical means. One example of a suitable mechanical shut-off mechanism is a preloaded spring mechanism that, when actuated, blocks fluid from moving through one of the system's tubes. An example of a suitable electrical device for implementing shut-off is a solenoid actuated valve, and a wide variety of alternatives will be apparent to persons skilled in the relevant arts. The shut-off mechanism may be designed to permanently disable the device, in which case the patient would have to obtain a new device to continue using the system. Alternatively, it may be configured to be resettable by a doctor (e.g., using an electronic shut-off mechanism that can be reset by entry of a password or a biometric key such as a fingerprint detector). After the patient is examined by the doctor (e.g., using blood tests to confirm healthy electrolyte levels), the doctor could provide a new device or reset the shut-off mechanism.
One application of some of the above-described embodiments is to implement a method of removing ingested food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This method includes the steps of: (a) siphoning a first portion of the ingested food out of the patient's stomach via the gastrostomy tube; (b) infusing liquid into the patient's stomach via the gastrostomy tube; and (c) siphoning at least some of the infused liquid out of the patient's stomach via the gastrostomy tube, together with a second portion of the ingested food. Optionally, this method may further include the steps of: (d) infusing liquid into the patient's stomach via the gastrostomy tube; and (e) siphoning at least some of the infused liquid out of the patient's stomach via the gastrostomy tube, together with a third portion of the ingested food, wherein step (d) is performed after step (c), and wherein step (e) is performed after step (d).
Another application of some of the above-described embodiments is to implement an apparatus for removing food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This apparatus includes: a connector configured to connect to a proximal end of the gastrostomy tube with a fluid-tight connection; a first fluid path provided between the connector and a drain port, configured to permit siphoning or pumping food from the patient's stomach out to the drain port; a second fluid path provided between the connector and an input port, configured to permit infusion of liquid from the input port into the patient's stomach; and a fluid circuit configured to alternately (a) open the first fluid path during a first interval of time to permit siphoning or pumping food out of the patient's stomach and (b) open the second fluid path during a second interval of time to permit infusion of the liquid in the reservoir into the patient's stomach.
Another application of some of the above-described embodiments is to implement a method of removing ingested material from a stomach of a patient fitted with an external gastrostomy connection to the stomach. This method includes: coupling a siphon tube to the connection so as to create a siphon system having an aggregate length in excess of 25 cm; and draining content of the stomach through the siphon tube.
Another application of some of the above-described embodiments is to implement a method of removing ingested material from a stomach of a patient fitted with an external gastrostomy connection to the stomach. This method includes the steps of: pumping a fluid through the connection into the stomach to increase fluid in the stomach without ingestion of fluid; and draining content of the stomach through the connection. Optionally, the fluid may include one or more of the following: water, a nutrient, a medication, and returned gastric juices.
Another application of some of the above-described embodiments is to implement an apparatus for removing ingested material from a stomach of a patient fitted with an external gastrostomy connection to the stomach. This apparatus includes: a fluid source for infusing fluid into the stomach through the connection; and a drain line for draining content of the stomach received from the connection. Optionally, a siphon system is used for passively draining content of the stomach, preferably using flat tubing. Optionally, a pump may be coupled to the fluid source for pumping fluid through the connection into the stomach.
Another application of some of the above-described embodiments is to implement a method of removing ingested food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This method includes the steps of: (a) extracting a portion of the matter contained in the patient's stomach via the gastrostomy tube; (b) removing stomach acid from the matter extracted in the extracting step; and (c) returning the stomach acid removed in the removing step to the patient's stomach via the gastrostomy tube. Optionally, the removing step includes the steps of: (i) filtering out solid portions from the matter extracted in the extracting step; and (ii) filtering a liquid resulting from step (i) using a semi-permeable membrane or an anionic exchange membrane. In this application, the extracting step may be implemented by siphoning or pumping.
Another application of some of the above-described embodiments is to implement an apparatus for removing food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This apparatus includes: a connector configured to connect to a proximal end of the gastrostomy tube with a fluid-tight connection; a filter configured to separate stomach acid from other matter; a first path from the connector to the filter, configured to route matter extracted from the patient's stomach into the filter; a pump configured to pump stomach acid that has been separated by the filter back into the patient's stomach; and a second path configured to route the other matter to a waste outlet. In this application, the matter extracted from the patient's stomach may be routed into the filter by pumping or siphoning. Optionally, this apparatus may further include a reservoir configured to hold liquid and a pump configured to pump the liquid from the reservoir into the patient's stomach via the connector.
Another application of some of the above-described embodiments is to implement a method of removing ingested food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This method includes the steps of: providing an apparatus for siphoning or pumping ingested food out of the patient's stomach via the gastrostomy tube; and limiting the number of times that the siphoning or pumping operation can be performed by the apparatus. The number of times that the siphoning or pumping operation can be performed may be limited by a variety of factors such as (a) elapsed time from a first use, (b) how many times siphoning or pumping of food has been performed, (c) how many times the apparatus has been connected to the gastrostomy tube, or (d) the volume of matter that has been extracted from the patient's stomach. Optionally, this method may further include the step of infusing liquid into the patient's stomach via the gastrostomy tube, wherein the infusing step is performed in alternation with the siphoning or pumping.
Another application of some of the above-described embodiments is to implement an apparatus for removing food from a patient's stomach via a gastrostomy tube that passes through the patient's abdominal wall into the patient's stomach. This apparatus includes: a connector configured to connect to a proximal end of the gastrostomy tube with a fluid-tight connection; and a first fluid path provided between the connector and a drain port, configured to permit, for a limited number of times only, siphoning or pumping food from the patient's stomach out to the drain port. The number of times that the siphoning or pumping can be performed may be limited by a variety of factors such as (a) elapsed time from a first use, (b) how many times siphoning or pumping of food has been performed, (c) how many times the apparatus has been connected to the gastrostomy tube, or (d) the volume of matter that has been extracted from the patient's stomach. Optionally, this apparatus may further include: a reservoir for holding liquid to be infused into the patient's stomach; a second fluid path from the reservoir to the connector, configured to permit infusion of the liquid in the reservoir into the patient's stomach; and a fluid circuit configured to alternately (a) open the first fluid path during a first interval of time to permit siphoning or pumping food from the patient's stomach and (b) open the second fluid path during a second interval of time to permit infusion of the liquid in the reservoir into the patient's stomach.
Note that while the system is described herein in the context of removing the ingested material from the patient's stomach, it can also be used to remove the ingested material from other portions of the patient's upper digestive tract (e.g., the jejunum).
Although the above discussion discloses various exemplary embodiments of the invention, it should be apparent that those skilled in the art can make variations and modifications that will achieve some of the advantages of the invention without departing from the true scope of the invention. Accordingly, other embodiments are within the scope of the following claims.