Colon cleaning system with automatic self-purging features
Systems and methods for cleaning a colon or other portion of an intestine include optional use of sensors to detect conditions of blockage of flow of materials within an evacuation channel used to remove fecal material from the body; and devices and methods for purging such blockages from the evacuation channel.
1. A method for purging blockage of an evacuation lumen of an intestinal cleaning system, comprising:
inserting the evacuation lumen at least 50 cm into a colon;
using a pump, evacuating waste from within the colon proximally through the evacuation lumen;
measuring a status of the evacuation lumen based on a reporting of at least one parameter including pressure and flow from at least one sensor positioned to detect an environmental condition in or near the evacuation lumen;
determining that the status indicates an incipient blockage of the evacuation lumen before the incipient blockage amounts to more than a 40% impairment of flow; and
initiating variation of a pumping direction through the evacuation lumen based on the determining, also before the incipient blockage amounts to more than a 40% impairment of flow, to thereby purge the incipient blockage.
2. The method of claim 1 , comprising determining a location of the incipient blockage relative to the evacuation lumen.
3. The method of claim 1 , further comprising:
automatically determining that the incipient blockage has been reduced; and
stopping the variation of the pumping direction.
4. The method of claim 1 , wherein the variation alternates the pressure in the evacuation lumen between distally-directed pressure and proximally-directed pressure.
5. The method of claim 4 , wherein the initiated variation reverses the pressure between distally-directed pressure and proximally-directed pressure at a frequency above 1 Hz.
6. The method of claim 4 , wherein the initiated variation reverses the pressure from distally-directed pressure to proximally-directed pressure at a frequency above 5 Hz.
7. The method of claim 1 wherein the status is evaluated at least 5 times per minute.
8. The method of claim 1 , wherein the evacuation lumen comprises a plurality of evacuation sub-lumens arranged alongside each other, and wherein the initiated variation changes the pressure so that a distally-directed pressure is applied to one sub-lumen while a proximally-directed pressure is applied to another sub-lumen.
9. The method of claim 8 , wherein the plurality of sub-lumens are joined by a connection allowing fluid communication, the connection being within 20 mm of a distal end of the sub-lumens.
10. The method of claim 1 , wherein the initiated variation is modulated based on a determined degree of incipient blockage.
11. The method of claim 1 , wherein the initiated variation is modulated based on a determined degree of reduction of flow in the evacuation lumen.
12. The method of claim 1 , comprising irrigating the colon with an irrigation fluid; and wherein the determining that the status indicates incipient blockage is while a rate of evacuation through the evacuation lumen matches or exceeds a rate of introduction of the irrigation fluid to the colon.
13. The method of claim 1 , comprising determining that the status indicates the incipient blockage while the incipient blockage comprises less than a 10% occlusion of a cross-section of the evacuation lumen.
14. The method of claim 1 , comprising determining that the status indicates the incipient blockage before the incipient blockage amounts to more than a 20% impairment of flow in the evacuation lumen.
15. The method of claim 1 , wherein the at least one sensor comprises a plurality of sensors selected from a group consisting of:
(a) a sensor positioned on an external surface of a distal portion of the evacuation lumen and external to the lumen;
(b) a sensor positioned within the evacuation lumen and within 5 mm of a distal end of the evacuation lumen;
(c) a sensor positioned within the evacuation lumen and 5-30 mm of the distal end of the evacuation lumen;
(d) a sensor positioned within the evacuation lumen and 3-160 cm from the distal end of the evacuation lumen;
(e) a sensor positioned within the evacuation lumen and 160-250 cm from the distal end of the evacuation lumen;
(f) a sensor positioned within the evacuation lumen and at least 250 cm from the distal end of the evacuation lumen; and
(g) a sensor positioned within a fluid supply tube which supplies a fluid flow to the distal portion of the evacuation lumen.
16. The method of claim 1 , wherein the status is measured from at least one of the group consisting of a change in:
(a) the pressure reported by the at least one sensor;
(b) when the at least one sensor comprises at least two sensors, a difference in the pressure between the at least two sensors;
(c) the flow reported by the at least one sensor;
(d) optical property; and
(e) bulk material property.
17. The method of claim 1 , wherein said measuring comprises sampling said at least one sensor at a rate of 5 Hz or higher.
18. The method of claim 1 , wherein said initiating variation of a pumping direction comprises applying a brief purging pulse which is shorter than 500 msec.
19. The method of claim 18 , where said purging pulse is strong enough to dislodge a weakly attached blockage without a complete interruption in evacuation through the evacuation lumen.
20. The method of claim 1 , wherein said pump is a bi-directional pump.