Remote sensing tonometric catheter apparatus

• US 5,186,172 A
• Filed: 06/02/1992
• Issued: 02/16/1993
• Est. Priority Date: 03/22/1982
• Status: Expired due to Term

• Current Assignee: Instrumentarium Dental Incorporated (Envista Holdings Corporation)
• Original Assignee: Mountpelier Investments, S.A.
• Inventors: Fiddian-Green, Richard G.
• Primary Examiner(s): Cohen, Lee S.
• Assistant Examiner(s): Lacyk, John P.
• Application Number:
  US07/892,631
• Time in Patent Office: 259 Days
• Field of Search: 128/632, 128/635, 128/637, 128/736, 128/748, 128/774, 128/750, 128/782, 128/672, 128/673, 204/407, 204/415, 204/433
• US Class Current: 600/353
• CPC Class Codes: A61B 5/145 Measuring characteristics of blood in vivo, e.g. gas concentration, pH value; Measuring characteristics of body fluids or tissues, e.g. interstitial fluid, cerebral tissuemeasuring of blood pressure or blood flow A61B5/02; non-radiation detecting or locating of foreign bodies in blood A61B5/06
• CPC Class Codes: A61B 5/14539 for measuring pH
• CPC Class Codes: A61B 5/14542 for measuring blood gases A61B5/14551 takes precedence
• CPC Class Codes: A61B 5/1459 invasive, e.g. introduced into the body by a catheter A61B5/1464 takes precedence
• CPC Class Codes: A61B 5/1473 invasive, e.g. introduced into the body by a catheter A61B5/1482 takes precedence
• CPC Class Codes: A61B 5/6853 with a balloon
• CPC Class Codes: A61M 2025/1061 having separate inflations tubes, e.g. coaxial tubes or tubes otherwise arranged apart from the catheter tube
• CPC Class Codes: A61M 25/10 Balloon catheters A61M25/0125 takes precedence; embolectomy A61B17/22032; retractors A61B17/02; inflatable balloons for placing stents or stent-grafts A61F2/958 ; stomach balloons for treatment of obesity A61F5/0003; oesophagal tubes A61J15/00
• CPC Class Codes: A61M 25/1011 Multiple balloon catheters

Abstract

A tonometric device for use in hollow viscus tonometry and remote sensing of patient fluid parameters is disclosed. The device is capable of monitoring certain critical fluid properties of interest, such as oxygen gases and carbon dioxide gases in the wall tissue itself of the patient'"'"'s organ, rather than monitoring such properties in a lumen of the organ. A walled sampling chamber, which is preferably an inflated balloon member, is provided on an elongated tube, with provisions for positioning the sampling chamber in direct contact with a wall portion of the patient'"'"'s internal organ.

Claims

1. A tonometric catheter apparatus for measuring a liquid fluid or gaseous fluid property indicative of the condition of an internal organ of a human or other mammal in vivo, comprising:

(a) an elongated tonometric catheter tube having a lumen extending longitudinally therethrough, said tube being composed of a first elastomeric material that is substantially impermeable to one or more liquid fluids or gaseous fluids of interest, said fluids of interest including oxygen gases and carbon dioxide gases;

(b) at least one walled sampling chamber on said catheter tube in fluid communication with the interior of said lumen, said walled sampling chamber being defined by a balloon member generally surrounding a portion of said tube and sealingly interconnected therewith, the wall of said balloon member being composed of a second material that is freely and selectively permeable to said one or more liquid fluids or gaseous fluids of interest, said second material being substantially impermeable to other liquid fluids or gaseous fluids, and said balloon member being inflated for forming an interior space between said balloon member and said catheter tube and for selectively positioning a portion of said balloon member substantially in direct contact with a wall portion of the internal organ in order to allow said one or more liquid fluids or gaseous fluids of interest from the tissue of the wall portion of the internal organ to permeate into said sampling chamber, with said tube extending to a position outside of the body of the human or other mammal, and with said lumen providing fluid communication between said sampling chamber and the outside of the body of the human or other mammal;

(c) sensor means for sensing the level of at least one of said liquid fluids or gaseous fluids of interest from the tissue of the wall portion of the internal organ present within said sampling chamber, said sensor means being disposed within said sampling chamber; and

(d) means for introducing a calibration fluid into said sampling chamber through said lumen in order to calibrate or recalibrate said sensor means while said balloon member is in said direct contact with the wall portion of the internal organ.

2. An apparatus according to claim 1, which additionally includes a temperature sensor disposed within said sampling chamber.

3. An apparatus according to claim 1, wherein said sensor means includes a chemically sensitive electronic transducer.

4. An apparatus according to claim 1, wherein said sensor means includes a chemically sensitive electronic transducer and a temperature sensor both disposed within said sampling chamber.

5. An apparatus according to claim 1, wherein said sensor means includes a chemically sensitive field effect transistor transducer.

6. An apparatus according to claim 1, wherein said sensor means includes a chemically sensitive field effect transistor transducer and a temperature sensor both disposed within said sampling chamber.

7. An apparatus according to claim 1, wherein said sensor means generates an electrical signal which is conveyed by a wire extending through said lumen to the outside of the body of the human or other mammal.

8. An apparatus according to claim 1, wherein said sensor means includes an optical sensor.

9. An apparatus according to claim 1, wherein said liquid fluid or gaseous fluid of interest includes pCO₂.

10. An apparatus according to claim 1, wherein said liquid fluid or gaseous fluid of interest includes pO₂.

11. An apparatus according to claim 1, wherein at least a portion of the tonometric catheter is composed of a polyester elastomer derived from the reaction of dimethylterephtalate 1,4-butanediol and α

-hydro-Ω

-hydroxypoly (oxytetramethylene).

12. An apparatus according to claim 1, wherein said sensor means generates a signal, and said apparatus includes means for sending said signal to the outside of the body of the human or other mammal.