Apparatus for determining a location in a body using a catheter and method of using such catheter

• US 20050096634A1
• Filed: 11/01/2003
• Published: 05/05/2005
• Est. Priority Date: 11/01/2003
• Status: Active Grant

• Current Assignee: Medtronic Incorporated (Medtronic Plc)
• Original Assignee: Medtronic Incorporated (Medtronic Plc)
• Inventors: Madsen, Michael O.
• Granted Patent: US 7,223,247 B2
• Time in Patent Office: Days
• US Class Current: 604/516
• CPC Class Codes: A61B 5/037 Measuring oesophageal pressure
• CPC Class Codes: A61B 5/073 Intestinal transmitters
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/4233 oesophagus

Abstract

Method of using an esophageal catheter. A distal end of the catheter is passed through the esophagus into the stomach of a patient. A constant pressure of gas is applied to the catheter. The back pressure of the gas is measured. The distal end of the catheter is pulled from the patient. An increase in the pressure measured is noted. A subsequent decrease in the pressure measured is then noted. The upper boundary of the lower esophageal sphincter is identified as a function of such decrease. The catheter is then used to place a remote monitoring device to the esophagus.

Claims

1. A method of using an esophageal catheter having a lumen, comprising the steps of:

passing a distal end of said catheter through an esophagus and a lower esophageal sphincter into a stomach of a patient;

introducing a flow of gas having a constant pressure to a proximate end of said lumen of said esophageal catheter;

measuring a lumen pressure of said gas in said lumen;

pulling back said distal end of said catheter from said patient;

noting an increase in said lumen pressure;

noting a subsequent decrease in said lumen pressure;

identifying an upper boundary of said lower esophageal sphincter based upon said decrease; and

utilizing said lumen of said catheter for suction to aid in attaching a monitoring device to said esophagus.

2. A method as in claim 1 further comprising the step of determining a baseline for said lumen pressure before said pulling back step and wherein said increase in said lumen pressure is relative to said baseline.

3. A method as in claim 2 wherein said distal end of said catheter is removed gradually.

4. A method as in claim 3 wherein said increase is measured as said distal end of said catheter enters said lower esophageal sphincter.

5. A method as in claim 4 wherein said decrease is measured as said distal end of said catheter passes an upper boundary of said lower esophageal sphincter.

6. A method as in claim 5 further comprising measuring a predetermined distance from said upper boundary of said lower esophageal sphincter.

7. A method as in claim 6 wherein said esophageal location is a predetermined distance above said upper boundary of said lower esophageal sphincter and wherein identification occurs said predetermined distance

8. A method as in claim 1 wherein said pulling back step is accomplished in a series of incremental steps with pauses in between each of said incremental steps and wherein said measuring step is accomplished during said pauses.

9. A method as in claim 1 wherein said gas comprises air.

10. A method of using a catheter having a lumen, comprising the steps of:

passing a distal end of said catheter through a first chamber and a restriction into a second chamber of a patient;

introducing an air flow having a constant pressure to a proximate end of said lumen;

measuring a lumen pressure in said lumen;

determining a baseline for said lumen pressure;

pulling back said distal end of said catheter from said patient;

noting an increase in said lumen pressure;

noting a subsequent decrease in said lumen pressure; and

identifying an upper boundary of said restriction upon said decrease; and

utilizing said lumen of said catheter for suction to aid in attaching a monitoring device to said esophagus.

11. A method as in claim 10 further comprising the step of determining a baseline for said lumen pressure before said pulling back step and wherein said increase in said lumen pressure is relative to said baseline.

12. A method as in claim 11 wherein said distal end of said catheter is removed gradually.

13. A method as in claim 12 wherein said increase is measured as said distal end of said catheter enters said restriction.

14. A method as in claim 13 wherein said decrease is measured as said distal end of said catheter passes an upper boundary of said restriction.

15. A method as in claim 14 further comprising measuring a predetermined distance from said upper boundary of said restriction.

16. A method as in claim 15 wherein said esophageal location is a predetermined distance above said upper boundary of said restriction and wherein identification occurs at said predetermined distance

17. A method as in claim 10 wherein said pulling back step is accomplished in a series of incremental steps with pauses in between each of said incremental steps and wherein said measuring step is accomplished during said pauses.

18. A method as in claim 10 wherein said gas comprises air.

19. An apparatus for determining an esophageal location in a patient having an esophagus, a stomach and a lower esophageal sphincter between said esophagus and said stomach, comprising:

a catheter, subsequently used for placing a monitoring device at said esophageal location in said patient, said catheter having a lumen, said catheter having a distal end capable of being passed through said esophagus and said lower esophageal sphincter into said stomach;

a source of gas having a constant pressure operatively coupled to a proximate end of said lumen; and

pressure measurement means for measuring a lumen pressure of said gas in said lumen;

whereby said distal end of said catheter may be removed from said patient while noting an increase in said lumen pressure relative to said baseline and subsequently noting a decrease in said lumen pressure thereby identifying an upper boundary of said lower esophageal sphincter upon said decrease.

20. An apparatus as in claim 19 further comprising means for determining a baseline for said lumen pressure before said pulling back step.

21. An apparatus as in claim 19 further comprising measuring a predetermined distance from said upper boundary of said lower esophageal sphincter.

22. An apparatus as in claim 19 wherein said esophageal location is a predetermined distance above said upper boundary of said lower esophageal sphincter and wherein identification occurs said predetermined distance

23. An apparatus as in claim 19 wherein said gas comprises air.

24. An apparatus for determining a location in a patient having first chamber, a second chamber and a restriction between said first chamber and said second chamber, comprising:

a catheter suitable for placing a monitoring device at said location in said patient, said catheter having a lumen, said catheter having a distal end capable of being passed through said first chamber and said restriction into said second chamber;

a source of gas having a constant pressure operatively coupled to a proximate end of said lumen; and

pressure measurement means for measuring a lumen pressure of said gas in said lumen;

whereby said distal end of said catheter may be removed from said patient while noting an increase in said lumen pressure relative to said baseline and subsequently noting a decrease in said lumen pressure thereby identifying an upper boundary of said lower esophageal sphincter upon said decrease.

25. An apparatus as in claim 24 further comprising means for determining a baseline for said lumen pressure before said pulling back step.

26. An apparatus as in claim 24 further comprising measuring a predetermined distance from said upper boundary of said restriction.

27. An apparatus as in claim 24 wherein said restriction is a predetermined distance above said upper boundary of said restriction and wherein identification occurs said predetermined distance

28. An apparatus as in claim 24 wherein said gas comprises air.