Intragastric implants with multiple fluid chambers
An intragastric obesity treatment implant promotes a feeling of satiety in the patient by contacting the insides of the stomach wall, reducing the space in the stomach, or otherwise reducing the amount of food consumed. One intragastric obesity treatment implant two inflatable balloons coupled via a flow restrictor through which fluid may flow in response to peristaltic motions of a patient's stomach. Additionally, one implant comprises a pumping chamber coupled to a reservoir, where the pumping chamber moves stomach fluids into the reservoir in response to peristaltic motions of the patient's stomach.
1. An intragastric obesity treatment implant, comprising:
a first inflatable balloon configured to be disposed in a patient's stomach, wherein the first inflatable balloon is configured to be inflated with a fluid after implantation in the patient's stomach;
a second inflatable balloon fluidly coupled to the first inflatable balloon such that the inflatable balloons have a longitudinal length that substantially spans the stomach and the second inflatable balloon is positioned adjacent the cardia, wherein the second inflatable balloon is configured to be inflated with a fluid after implantation in the patient's stomach;
an elongated member extending between and spacing the first and second inflatable balloons, the elongated member defining a fluid passageway in communication with the first and second balloons, the elongated member including a flow restrictor that reduces the size of the passageway while allowing and regulating fluid flow between the first and the second inflatable balloons, wherein the first inflatable balloon is constructed to receive an applied peristaltic inward pressure on the first inflatable balloon that compresses the first balloon to increase the pressure of the fluid within the first inflatable balloon to a pressure that exceeds the pressure of the fluid in the second inflatable balloon to displace a portion of the fluid within the first inflatable balloon through the flow restrictor and into the second inflatable balloon, and wherein the second inflatable balloon is constructed to receive the portion of the fluid from the first inflatable balloon to expand the second inflatable balloon to exert pressure on the cardia and induce a feeling of satiety in the patient and to equalize fluid pressure in the first and second inflatable balloons, and wherein the quantity of the portion of fluid displaced is based on a difference in pressure between fluid in the first inflatable balloon and fluid in the second inflatable balloon.
2. The implant of claim 1 , wherein the first inflatable balloon and the second inflatable balloon comprise a plurality of external grooves oriented along an axis connecting the two balloons and configured to allow ingested food to pass by so that the ingested food may be digested by the patient.
3. The implant of claim 2 , wherein the first inflatable balloon comprises eight grooves, and wherein the second inflatable balloon comprises eight grooves.
4. The implant of claim 1 , wherein the flow restrictor comprises a narrow portion connecting the first inflatable balloon and the second inflatable balloon, and further including an elastic band wrapped around the narrow portion.
5. The implant of claim 1 , wherein the flow restrictor comprises a narrow portion connecting the first inflatable balloon and the second inflatable balloon, and wherein the narrow portion includes fluted wings configured to provide structural support to the narrow portion.
6. The implant of claim 1 , further including a single evacuation valve that may be accessed with an aspirator to simultaneously evacuate both the first and second inflatable balloons.
7. The implant of claim 1 , wherein the implant has a dog-bone shape, with identical first and second inflatable balloons defining enlarged outer ends joined by a smaller middle portion.
8. The implant of claim 1 , wherein the first and second inflatable balloons each includes an inner end wall diametrically-oriented with respect to the longitudinal axis, the end walls being joined in abutting relationship to form a partition in the implant, and wherein the flow restrictor comprises fluid passageways across the partition.
9. The implant of claim 8 , further including a valve positioned in the partition that permits flow from the first inflatable balloon to the second inflatable balloon but prevents reverse flow therebetween, the valve having a flow rate capacity greater than the fluid passageways of the flow restrictor.
10. The implant of claim 8 , wherein the first and second inflatable balloons have a generally uniform longitudinal exterior shape.
11. The implant of claim 1 , wherein the second inflatable balloon is at least three times the volume of the first inflatable balloon.
12. The implant of claim 1 , wherein the combined volumes of the first and second inflatable balloons is at least about 400 ml of saline.
13. The implant of claim 1 , further including a tether having a first fluid passage fluidly connecting the first and second inflatable balloons and having the constantly open flow restrictor therein.
14. The implant of claim 13 , wherein the tether also has a second passage in addition to the first passage, the second passage having one-way flow valves therein at each end adjacent each of the first and second inflatable balloons that prevent fluid from traveling from the second passage into the respective first or second inflatable balloon but permit flow from the respective first or second inflatable balloon into the second passage upon a predetermined pressure differential thereacross.
15. The implant of claim 13 , wherein the first fluid passage has a size that permits a maximum flow rate of about 1-20 ml/s.
16. The implant of claim 1 , wherein the first and second inflatable balloons are constructed to expand and contract to equalize fluid pressure in the first and second inflatable balloons.