US 5,433,216 A · Intra-abdominal pressure measurement apparatus and method

Abstract

An improved tonometric catheter can be configured to have one or more pressure transmitting chambers for sensing the internal pressure such as the internal abdominal pressure of a subject. The tonometric catheter is inserted into the patient such as a nasogastric catheter. The pressure sensing chamber in the form of a balloon is insufflated with a pressure transmitting medium when the balloon is in the desired location. After insufflation of the chamber the catheter is connected to a pressure transducer or manometer which then provides an output reading the internal pressure of the subject. The tonometric catheter with a pressure sensing chamber is useful for sensing the internal abdominal pressure such as during laparoscopic surgery. The sensing of internal pressure can also be used at other locations along the gut or in the cranium. The monitoring of internal pressure is also useful in conjunction with the monitoring of internal pH. The monitored internal pressure can be used to calculate a correction factor which is in turn applied to the calculation of pHi from the measured concentration of gases inside the subject. The pressure sensing chamber can also be used as a location device to ensure the proper location of the chamber and hence the related apparatus on a catheter.

Claims39

Dependent claims

A tonometric catheter apparatus for measuring the internal pressure of a human or other mammal comprising:

(a) an elongated tonometric catheter tube having at least one lumen extending longitudinally therethrough;
(b) at least one walled pressure transmitting chamber on said catheter tube in pressure transmitting communication with the interior of said lumen, said walled pressure transmitting chamber generally surrounding a portion of said catheter tube and being sealingly interconnected therewith, being composed of a wall material being substantially impermeable to liquid fluids or wherein at least a portion of the wall of said chamber being composed of a wall material that is freely and selectively permeable to one or more liquid fluids or gaseous fluids of interest, said wall material being substantially impermeable to other interfering liquid fluids or gaseous fluids, and wherein said pressure transmitting chamber forms an interior space with said catheter tube in order to allow the transmission of change in pressure through said pressure transmitting chamber to the interior of said lumen via a pressure transmitting medium;
and
(c) pressure sensor means for measuring the pressure of said pressure transmitting medium.

1 more element

A tonometric catheter apparatus for measuring at least one 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 comprising a first lumen and a second lumen extending longitudinally therethrough;
(b) at least one walled sampling chamber on said catheter tube in fluid communication with the interior of said first lumen, said walled sampling chamber generally surrounding a portion of said catheter tube and being sealingly interconnected therewith., at least a portion of the wall of said sampling chamber being composed of a wall material that is freely and selectively permeable to one or more liquid fluids or gaseous fluids of interest, said wall material being substantially impermeable to other interfering liquid fluids or gaseous fluids, and said sampling chamber forming an interior space with said catheter tube 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 a sampling medium, with said catheter tube extending to a position outside of the body of the human or other mammal;
(c) first sensor means for sensing the level of at least one of said liquid fluids or gaseous fluids of interest permeated from the tissue of the wall portion of the internal organ with said fluid sampling medium in sampling chamber;
(d) at least one walled pressure transmitting chamber on said catheter tube in pressure transmitting communication with the interior of said second lumen, said pressure transmitting chamber generally surrounding a portion of said catheter tube and being sealingly interconnected therewith, the wall of said pressure transmitting chamber being composed of a wall material that is substantially impermeable to liquid fluids or gaseous fluids normally encountered in vivo;
(e) a pressure transmitting medium within said pressure transmitting chamber for transmitting pressure received by said walled pressure transmitting chamber to said second lumen;
and
(f) pressure sensor means for sensing the pressure of said pressure transmitting medium.

4 more elements

A method of monitoring the internal pressure of a human or other mammal and at least one liquid fluid or gaseous fluid property indicative of the pH of an internal organ of a human or mammal, in vivo, comprising the steps of:

(a) inserting an elongated tonometric catheter tube having at least one lumen extending longitudinally therethrough into said human or other mammal;
said catheter having at least one walled pressure transmitting and sampling chamber in fluid communication with the interior of said lumen, said walled pressure transmitting and sampling chamber generally surrounding a portion of said catheter tube and being sealingly interconnected therewith, said pressure transmitting and sampling chamber forming an interior space with said catheter tube in order to allow one or more liquid fluids or gaseous fluids of interest from the tissue of the walled portion of the internal organ to permeate into said pressure transmitting and sampling chamber and to allow the transmission of change in pressure through said pressure transmitting and sampling chamber to the interior of said lumen via a pressure transmitting medium;
(b) providing a first sensor means for sensing the level of at least one of said liquid fluids or gaseous fluids of interest permeated from a tissue of the wall portion of the internal organ with a sampling medium;
(c) receiving a pressure indicating signal through said lumen;
and
(d) providing a second sensor means for receiving said pressure indicating signal and converting it into a human readable form.

3 more elements

Dependencies are inferred from the claim text.

Intra-abdominal pressure measurement apparatus and method

Life of this patent

Intra-abdominal pressure measurement apparatus and method

Life of this patent

Abstract

Claims39