Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
113 words
Apparatus for use in a system for measuring osmotic pressure in a bloodstream, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having first and second lumens therein and a port adapted to permit contact of the interior of said catheter with said bloodstream; at least one tube of a material that is semi-permeable to a fluid of said bloodstream, said tube fluidly connecting said first lumen with said second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in airtight and watertight seals; and a pressure sensor means for measuring the pressure in said first lumen.
Claim 2
Dependent Claim
113 words
Apparatus for use in a system for measuring osmotic pressure in a bloodstream, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having first and second lumens therein and a port adapted to permit contact of the interior of said catheter with said bloodstream; at least one tube of a material that is semi-permeable to a fluid of said bloodstream, said tube fluidly connecting said first lumen with said second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in airtight and watertight seals; and a pressure sensor means for measuring the pressure in said first lumen.
Claim 3
Dependent Claim
146 words
Apparatus for measuring osmotic pressure, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having three lumens, and a port adapted to permit passage of fluid from said bloodstream into said catheter means; at least one tube of a material that is semi-permeable to said fluid from said bloodstream, said tube fluidly connecting a first lumen with a second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in airtight and watertight seals; the third lumen being in fluid communication with the exterior of said tube opposite said port; a first pressure sensor means for measuring the pressure of fluid in said first lumen; and a second pressure sensor means for measuring the pressure of fluid in the third lumen, said third lumen opening to the bloodstream at said port.
Claim 4
Dependent Claim
146 words
Apparatus for measuring osmotic pressure, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having three lumens, and a port adapted to permit passage of fluid from said bloodstream into said catheter means; at least one tube of a material that is semi-permeable to said fluid from said bloodstream, said tube fluidly connecting a first lumen with a second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in airtight and watertight seals; the third lumen being in fluid communication with the exterior of said tube opposite said port; a first pressure sensor means for measuring the pressure of fluid in said first lumen; and a second pressure sensor means for measuring the pressure of fluid in the third lumen, said third lumen opening to the bloodstream at said port.
Claim 5
Dependent Claim
154 words
Apparatus for measuring osmotic pressure, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having three lumens and a port adapted to permit contact of the interior of said catheter with said bloodstream; at least one tube of material that is semi-permeable to a fluid of said bloodstream fluidly connecting a first lumen with a second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in an airtight and watertight seal, said material being permeable to substances having a molecular weight not greater than 30,000; the third lumen being in fluid communication with the exterior of said tube opposite said port; a first pressure sensor means for measuring the pressure in said first lumen; and a second pressure sensor means for measuring the pressure in the third lumen, said third lumen opening to said bloodstream at said port.
Claim 6
Dependent Claim
154 words
Apparatus for measuring osmotic pressure, said apparatus comprising: catheter means for insertion in a subject's bloodstream, said catheter means having three lumens and a port adapted to permit contact of the interior of said catheter with said bloodstream; at least one tube of material that is semi-permeable to a fluid of said bloodstream fluidly connecting a first lumen with a second lumen and extending across said port, the ends of said tube being connected to said first and second lumens, respectively, in an airtight and watertight seal, said material being permeable to substances having a molecular weight not greater than 30,000; the third lumen being in fluid communication with the exterior of said tube opposite said port; a first pressure sensor means for measuring the pressure in said first lumen; and a second pressure sensor means for measuring the pressure in the third lumen, said third lumen opening to said bloodstream at said port.
Claim 7
Dependent Claim
37 words
Apparatus as claimed in claim 1, 2 or 3 wherein said apparatus further comprising value means for selectively connecting said third lumen to a source of fluid pressure for flushing fluid past said tube to remove debris.
Claim 8
Dependent Claim
39 words
Apparatus as claimed in claim 1, 2 or 3 wherein said tube is filled with fibers, said tube having a fluid volume which is reduced by said fibers, with said fibers providing support for said tube against external pressure.
Claim 9
Independent Claim
117 words
A method for measuring osmotic pressure in the bloodstream comprising the steps: inserting a multiple-lumen catheter into the circulatory system of a subject, said catheter having first, second, and third lumens filled with a physiologically normal fluid and having said first and second lumens fluidly connected by at least one semi-permeable tube extending across a port in said catheter, and a third lumen in communication with the exterior of said tube opposite said port; measuring the fluid pressure in said first lumen; measuring the fluid pressure in said third lumen; and adding the pressure of the fluid in the first lumen to the pressure of the fluid in the third lumen to determine the intravascular osmotic pressure.
Claim 10
Independent Claim
117 words
A method for measuring osmotic pressure in the bloodstream comprising the steps: inserting a multiple-lumen catheter into the circulatory system of a subject, said catheter having first, second, and third lumens filled with a physiologically normal fluid and having said first and second lumens fluidly connected by at least one semi-permeable tube extending across a port in said catheter, and a third lumen in communication with the exterior of said tube opposite said port; measuring the fluid pressure in said first lumen; measuring the fluid pressure in said third lumen; and adding the pressure of the fluid in the first lumen to the pressure of the fluid in the third lumen to determine the intravascular osmotic pressure.
Claim 11
Dependent Claim
37 words
A method as claimed in claim 6 further comprising the step of periodically flushing a physiologically normal fluid through said third lumen past said tube to prevent thrombic activity from interfering with the measurement of osmotic pressure.