Catheter

Claim 2

A catheter for placement in an artery, vein or fistula vessel of a patient, through which blood may be with-drawn from or delivered to the patient, which comprises a catheter wall, the inside surface of which defines a lumen having a cross-sectional area in a proximal end region of the catheter which is larger than the cross-sectional area of the lumen defined in a distal end region of the catheter, the cross-sectional area of the lumen diminishing substantially uniformly from the proximal end region to the distal end region.

Claim 3

A catheter according to claim 1, in which the distal end of the inside surface of the catheter wall defines an end opening through which blood may be passed into and out of the lumen.

Claim 4

A catheter according to claim 1, in which two to six side openings are provided in the wall of the catheter.

Claim 5

A catheter according to claim 3, in which two to three pairs of side openings are provided in the wall of the catheter, the two openings of each pair being in diametrically opposed relationship, and each pair of openings being longitudinally spaced away from one another.

Claim 6

A catheter according to claim 4, in which adjacent pairs of diametrically opposed openings are arranged at right angles to one another.

Claim 7

A catheter according to claim 3 in which the total area of the side openings in the wall of the catheter together with the area of the end opening defined by the distal end of the catheter, is at least as great as the smallest cross-sectional area of the lumen through which blood may be passed.

Claim 8

A catheter according to claim 3, in which the total area of the side openings in the wall of the catheter is at least as great as the smallest cross-sectional area of the lumen through which blood may be passed.

Claim 9

A catheter according to claim l, in which the proximal end of the catheter is coaxially connected to a hub having a bore of cross-sectional area at least as large as the largest cross-sectional area of the lumen, the hub in turn being coaxially connected to a hollow cylindrical body having a closure at its free end.

Claim 10

A catheter according to claim 8, in which the hollow cylindrical body has a hollow cylindrical side arm leading into the side of the hollow cylindrical body.

Claim 11

A catheter according to claim 9, in which the free end of the side arm is provided with means for connection to a blood line.

Claim 12

A catheter according to claim 9, in which the free end of the side arm is sealed closed by means of a removable resealable plug through which a needle may be passed.

Claim 13

A catheter according to claim 8, in which a hollow needle is provided which passes through the closure at the free end of the hollow cylindrical body and coaxially through the hollow cylindrical body, through the hub and through the catheter so that the point of the needle protrudes beyond the distal end of the catheter.

Claim 14

A catheter according to claim 12, in which the hollow needle is provided with female luer means at its proximal end for receiving the nose of a syringe.

Claim 15

A catheter according to claim 12, in which the closure at the free end of the hollow cylindrical body comprises a flexible tube coaxially connected to the free end of the hollow cylindrical body, and a removeable resealable plug sealing closed the free end of the flexible tube through which the needle passes.

Claim 16

A catheter according to claim 1, in which the thickness of the catheter side wall is progressively greater from the region where the cross-sectional area of the lumen is larger to the region where the cross-sectional area of the lumen is smaller.

Claim 17

A catheter according to claim 1, in which the inner diameter of the catheter ranges from about 0.02 to about 0.07 inches.

Claim 18

A catheter according to claim 16, in which the inner diameter of the catheter ranges from about 0.03 to about 0.06 inches.

Claim 19

A catheter according to claim 12, in which the inner diameter of the needle is from about 0.02 to about 0.05 inches.

Claim 20

A catheter according to claim 18, in which the inner diameter of the needle is from about 0.33 to about 0.04 inches.

Claim 21

A catheter for placement in an artery, vein or fistula vessel of a patient, through which blood may be with-drawn from or delivered to the patient, which comprises a catheter wall, at least one side opening being provided in the wall of the catheter in the distal end region thereof, a hub having a bore, connected coaxially to the proximal end of the catheter, a hollow cylindrical body coaxially connected to the hub and having connection means at its free end, for connection to a blood line, a hollow cylindrical side arm leading into the side of the hollow cylindrical body and having means for connection to a blood line, a hollow needle defining an inner lumen through which blood may be delivered to the patient, which passes coaxially through the hollow cylindrical body, through the hub and through the catheter so that the point of the needle protrudes beyond the distal end of the catheter, the outer surface of the needle and the inner surface of the catheter wall defining an annular outer lumen, the cross-sectional area of the outer lumen diminishing to a minimum cross-sectional area at the distal end of the catheter from a position distal to the side opening in the wall of the catheter, said minimum cross-sectional area of the outer lumen corresponding to the outer cross-sectional area of the needle so that the distal end of the catheter seals against the wall of the needle, said annular outer lumen being in communication with the hollow cylindrical body and the hollow cylindrical side arm.

Claim 22

A catheter for placement in an artery, vein or fistula vessel of a patient, through which blood may be with-drawn from or delivered to the patient, which comprises a catheter wall, at least one side opening being provided in the wall of the catheter in the distal end region thereof, a hub having a bore, connected coaxially to the proximal end of the catheter, a hollow cylindrical body coaxially connected to the hub and having connection means at its free end, for connection to a blood line, a hollow cylindrical side arm leading into the side of the hollow cylindrical body and having means for connection to a blood line, a hollow needle defining an inner lumen through which blood may be delivered to the patient, which passes coaxially through the hollow cylindrical body, through the hub and through the catheter so that the point of the needle protrudes beyond the distal end of the catheter, the outer surface of the needle and the inner surface of the catheter wall defining an annular outer lumen, the cross-sectional area of the outer lumen diminishing to a minimum cross-sectional area at the distal end of the catheter from a position distal to the side opening in the wall of the catheter, said minimum cross-sectional area of the outer lumen corresponding to the outer cross-sectional area of the needle so that the distal end of the catheter seals against the wall of the needle, said annular outer lumen being in communication with the hollow cylindrical body and the hollow cylindrical side arm.

Claim 23

A catheter for placement in an artery, vein or fistula vessel of a patient, through which blood may be with-drawn from and delivered to the patient, which comprises a first catheter, at least one side opening being provided in the wall of said first catheter through which blood may be passed, a second catheter defining an inner lumen being dis-posed coaxially within the first catheter and in which the distal end of said second catheter defines an end opening through which blood may be passed, the inner surface of the first catheter wall and the outer surface of the second catheter defining an annular outer lumen through which blood may be withdrawn from the patient, the cross-sectional area of the outer lumen diminishing to a minimum cross-sectional area, at the distal end of the catheter from a position distal to the opening in the wall of the first catheter, said minimum cross-sectional area of the outer lumen corresponding to the outer cross-sectional area of the second catheter so that the distal end of the first catheter seals against the wall of the second catheter.

Claim 24

A catheter for placement in an artery, vein or fistula vessel of a patient, through which blood may be with-drawn from and delivered to the patient, which comprises a first catheter, at least one side opening being provided in the wall of said first catheter through which blood may be passed, a second catheter defining an inner lumen being dis-posed coaxially within the first catheter and in which the distal end of said second catheter defines an end opening through which blood may be passed, the inner surface of the first catheter wall and the outer surface of the second catheter defining an annular outer lumen through which blood may be withdrawn from the patient, the cross-sectional area of the outer lumen diminishing to a minimum cross-sectional area, at the distal end of the catheter from a position distal to the opening in the wall of the first catheter, said minimum cross-sectional area of the outer lumen corresponding to the outer cross-sectional area of the second catheter so that the distal end of the first catheter seals against the wall of the second catheter.

Claim 25

A catheter according to claim 21, in which a removable trocar is located in said second catheter so that the point of the trocar protrudes through the opening defined by the distal end of said second catheter.

Claim 26

A catheter according to claim 21, in which the second catheter defines an inner lumen having a cross-sectional area in a proximal end region thereof which is larger than the cross-sectional area of the inner lumen in a distal end region thereof.

Claim 27

A catheter according to claim 21, additionally comprising a hub having a bore, connected coaxially to the proximal end of said first catheter, a hollow cylindrical body coaxially connected to the hub and having a removable closure and means for connection to a blood line at its free end, a hollow cylindrical side arm leading into the side of the hollow cylindrical body having means at its free end for connection to a blood line, said second catheter leading rearwardly from its distal end through the bore of the hub and to the free end of the hollow cylindrical body where the outer surface of the wall of the second catheter is sealed against the inner surface of the wall of the hollow cylindrical body so that an annular blood flow passage in communication with said annular outer lumen and the hollow cylindrical side arm is defined by the outer surface of the wall of the second catheter and the inner surface of the wall of the hollow cylindrical body, a removable trocar which passes through the removable closure at the free end of the hollow cylindrical body and coaxially through the second catheter so that the point of the trocar protrudes beyond the distal end of the catheter, the cross-sectional area of the bore of the hub being at least as large as the sum of the outer cross-sectional area of the second catheter where it passes through the bore of the hub and the largest cross-sectional area of said annular outer lumen.

Claim 28

A catheter according to claim 24, in which the removable closure and means for connection to a blood line comprises a flexible tube coaxially connected to the free end of the hollow cylindrical body, and a removable resealable plug sealing closed the free end of the flexible tube and through which the removable trocar passes.

Claim 29

A catheter according to claim 20, in which the outer lumen has a cross-sectional area in a proximal end region of the catheter which is larger than the cross-sectional area of the outer lumen in a distal end region of the catheter, the annular outer lumen thereby progressively increasing in cross-sectional area rearwardly towards the proximal end of the catheter from the distal end region, the cross-sectional area of the bore of the hub being at least as large as the sum of the outer cross-sectional area of the needle and the largest cross-sectional area of said annular outer lumen.

Claim 30

A catheter according to claim 21 in which the outer lumen has a cross-sectional area in a proximal end region of said first catheter which is larger than the cross-sectional area of the outer lumen in a distal end region of said first catheter, the annular outer lumen thereby progressively increasing in cross-sectional area rearwardly towards the proximal end of the first catheter from the distal end region thereof.

Claim 31

A catheter according to claim 20 or claim 26, in which the hollow needle defining the inner lumen is retractable over a short distance so that the point of the needle may be retracted into a retracted position after placement of the catheter in which the distal end of the catheter seals against the wall of the needle and around the point thereof.

Claim 32

A catheter according to claim 28, in which locator means is provided for locating the needle in a placement position in which the point of the needle protrudes beyond the distal end of the catheter and for locating the needle in its retracted position.