Patents by Inventor Zbylut J. Twardowski
Zbylut J. Twardowski has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 7695450Abstract: A catheter for hemodialysis comprises a flexible catheter tube defining a plurality of separate lumens. The catheter defines an arc angle of generally U-shape in its natural, unstressed configuration. Thus, the catheter may be implanted with a distal catheter portion residing in a vein of the patient, the distal catheter portion being of substantially the shape of the vein in its natural, unstressed condition. Also, a proximal catheter portion resides in a surgically created tunnel extending from the vein and through the skin of the patient, this section of the catheter also being typically in its natural, unstressed condition. Thus blood may be removed from the vein through one lumen of the catheter, and blood may be returned to the vein through another lumen of the catheter, while the catheter is subject to long term indwelling in the body.Type: GrantFiled: March 28, 1995Date of Patent: April 13, 2010Assignee: Curators of the University of Missouri, The University of MissouriInventors: Zbylut J. Twardowski, John C. Van Stone, W. Kirt Nichols
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Patent number: 6592565Abstract: The method of selecting and implanting a permanent venous catheter into a patient for use in chronic, extracorporeal blood treatment procedures. The method comprises determining the Body Surface Area of the patient. One then selects a permanent venous catheter having an actual length which is within 10% of a desired length as indicated in a Table found in this application for the Body Surface Area of the particular patient and a particular vein through which the catheter is to extend. Also, the internal diameter of the tubing is preferably adjusted in a manner correlating with the catheter length. Following catheter selection, the venous catheter is implanted in the venous system of the patient with the distal tip of the catheter being in or adjacent to the upper right atrium of the heart.Type: GrantFiled: April 26, 2001Date of Patent: July 15, 2003Inventor: Zbylut J. Twardowski
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Publication number: 20030023198Abstract: The method of selecting and implanting a permanent venous catheter into a patient for use in chronic, extracorporeal blood treatment procedures. The method comprises determining the Body Surface Area of the patient. One then selects a permanent venous catheter having an actual length which is within 10% of a desired length as indicated in a Table found in this application for the Body Surface Area of the particular patient and a particular vein through which the catheter is to extend. Also, the internal diameter of the tubing is preferably adjusted in a manner correlating with the catheter length. Following catheter selection, the venous catheter is implanted in the venous system of the patient with the distal tip of the catheter being in or adjacent to the upper right atrium of the heart.Type: ApplicationFiled: April 26, 2001Publication date: January 30, 2003Inventor: Zbylut J. Twardowski
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Patent number: 6423050Abstract: A central-vein cathether is locked by anticoagulant and bactericidal solutions separated by an air bubble. The anticoagulant is injected first, then the air bubble, and then the bactericidal solution, so that the anticoagulant is located close to the catheter tip in contact with the blood and the bacterial solution is located close to the catheter hub, where bacteria contamination is common. The air bubble prevents mixing of the solutions. A multi-chamber syringe facilitates sequential injection of the anticoagulant, air and bactericidal agent with only one connection, decreasing chances of contamination. The syringe includes internal and external coaxial barrels separated by seals, the external barrel having a discharge opening located off center in the barrel bottom, and the internal barrel having two or three chambers, each with an outlet opening.Type: GrantFiled: June 16, 2000Date of Patent: July 23, 2002Inventor: Zbylut J. Twardowski
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Patent number: 6146536Abstract: A hemodialyzer apparatus comprises a reusable dialyzer membrane as well as reusable blood flow path and dialysis flow path units. The apparatus automatically primes itself and makes dialysis solution from dry chemicals, concentrates, and fresh water which is provided to the apparatus. Also, after use, the apparatus automatically prepares cleaning and rinsing solution for the cleaning and rinsing of the dialyzer membrane as well as the dialyzate and blood flow path means, to provide a system which is so simplified in terms of automatic operation that it may be usable for daily dialysis at home.Type: GrantFiled: April 12, 1999Date of Patent: November 14, 2000Inventor: Zbylut J. Twardowski
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Patent number: 6132616Abstract: A method for flushing and filling of an extracorporeal blood circulation system of a dialysis machine is disclosed. The machine has a dialyzer, a separate dialysis liquid circuit flowing through a dialysate side of the dialyzer with the extracorporeal blood circulation system flowing through a blood side of the dialyzer for removal of impurities from the blood and the dialysate and blood sides of the dialyzer separated by a hemodialyzer membrane. The method comprises the steps of transporting dialysis liquid from the dialysis liquid circuit in the dialysate side of the dialyzer through the hemodialyzer membrane into the blood side of the dialyzer and the extracorporeal blood circulation system to flush and fill the system and conducting a dialysis treatment.Type: GrantFiled: November 7, 1994Date of Patent: October 17, 2000Inventors: Zbylut J. Twardowski, Rodney S. Kenley
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Patent number: 5961486Abstract: Blood is circulated through a multiple lumen catheter which connects between a vein of a patient and the blood treatment device. The catheter and the lumens thereof each define distal ends which are positioned within the vein. By this invention, one withdraws blood from the vein through one of the lumens at a flow rate of at least about 200 ml./min. while also inserting blood into the vein through another of said lumens at a similar flow rate. The distal ends of the lumens are longitudinally spaced from each other by no more than about 5 mm. It has been found that the following advantages can be achieved by this method: less clot formation coupled with low direct blood recirculation and longer catheter survival. Also, the catheter of this invention works well in either direction of blood flow through the respective lumens.Type: GrantFiled: November 5, 1998Date of Patent: October 5, 1999Inventors: Zbylut J. Twardowski, W. Kirt Nichols, John C. Van Stone
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Patent number: 5902476Abstract: A hemodialyzer apparatus comprises a reusable dialyzer membrane as well as reusable blood flow path and dialysis flow path units. The apparatus automatically primes itself and makes dialysis solution from dry chemicals, concentrates, and fresh water which is provided to the apparatus. Also, after use, the apparatus automatically prepares cleaning and rinsing solution for the cleaning and rinsing of the dialyzer membrane as well as the dialyzate and blood flow path means, to provide a system which is so simplified in terms of automatic operation that it may be usable for daily dialysis at home.Type: GrantFiled: March 28, 1997Date of Patent: May 11, 1999Inventor: Zbylut J. Twardowski
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Patent number: 5685867Abstract: Blood is circulated through a multiple lumen catheter which connects between a vein of a patient and the blood treatment device. The catheter and the lumens thereof each define distal ends which are positioned within the vein. By this invention, one withdraws blood from the vein through one of the lumens at a flow rate of at least about 200 ml./min. while also inserting blood into the vein through another of said lumens at a similar flow rate. The distal ends of the lumens are longitudinally spaced from each other by no more than about 5 mm. It have been found that the following advantages can be achieved by this method: less clot formation coupled with low direct blood recirculation and longer catheter survival. Also, the catheter works well in either direction of blood flow through the respective lumens.Type: GrantFiled: June 7, 1995Date of Patent: November 11, 1997Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, W. Kirt Nichols, John C. Van Stone
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Patent number: 5569182Abstract: Blood is circulated through a multiple lumen catheter which connects between a vein of a patient and the blood treatment device. The catheter and the lumens thereof each define distal ends which are positioned within the vein. By this invention, one withdraws blood from the vein through one of the lumens at a flow rate of at least about 200 ml./min. while also inserting blood into the vein through another of said lumens at a similar flow rate. The distal ends of the lumens are longitudinally spaced from each other by no more than about 5 mm. It have been found that the following advantages can be achieved by this method: less clot formation coupled with low direct blood recirculation and longer catheter survival. Also, the catheter works well in either direction of blood flow through the respective lumens.Type: GrantFiled: February 9, 1995Date of Patent: October 29, 1996Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, W. Kirt Nichols, John C. Van Stone
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Patent number: 5509897Abstract: A catheter for hemodialysis comprises a flexible catheter tube defining a plurality of separate lumens. The catheter defines an arc angle of generally U-shape in its natural, unstressed configuration. Thus, the catheter may be implanted with a distal catheter portion residing in a vein of the patient, the distal catheter portion being of substantially the shape of the vein in its natural, unstressed condition. Also, a proximal catheter portion resides in a surgically created tunnel extending from the vein and through the skin of the patient, this section of the Catheter also being typically in its natural, unstressed condition. Thus blood may be removed from the vein through one lumen of the catheter, and blood may be returned to the vein through another lumen of the catheter, while the catheter is subject to long term indwelling in the body.Type: GrantFiled: February 15, 1995Date of Patent: April 23, 1996Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, John C. Van Stone, W. Kirt Nichols
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Patent number: 5484397Abstract: A hemodialyzer apparatus comprises a reusable dialyzer membrane as well as reusable blood flow path and dialysis flow path units. The apparatus automatically primes itself and makes dialysis solution from dry chemicals, concentrates, and fresh water which is provided to the apparatus. Also, after use, the apparatus automatically prepares cleaning and rinsing solution for the cleaning and rinsing of the dialyzer membrane as well as the dialyzate and blood flow path means, to provide a system which is so simplified in terms of automatic operation that it may be usable for daily dialysis at home.Type: GrantFiled: November 22, 1993Date of Patent: January 16, 1996Inventor: Zbylut J. Twardowski
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Patent number: 5405320Abstract: A catheter for hemodialysis comprises a flexible catheter tube defining a plurality of separate lumens. The catheter defines an arc angle of generally U-shape in its natural, unstressed configuration. Thus, the catheter may be implanted with a distal catheter portion residing in a vein of the patient, the distal catheter portion being of substantially the shape of the vein in its natural, unstressed condition. Also, a proximal catheter portion resides in a surgically created tunnel extending from the vein and through the skin of the patient, this section of the catheter also being typically in its natural, unstressed condition. Thus blood may be removed from the vein through one lumen of the catheter, and blood may be returned to the vein through another lumen of the catheter, while the catheter is subject to long term indwelling in the body.Type: GrantFiled: April 8, 1993Date of Patent: April 11, 1995Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, John C. Van Stone, W. Kirt Nichols
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Patent number: 5336165Abstract: A hemodialyzer apparatus comprises a reusable dialyzer membrane as well as reusable blood flow path and dialysis flow path units. The apparatus automatically primes itself and makes dialysis solution from dry chemicals, concentrates, and fresh water which is provided to the apparatus. Also, after use, the apparatus automatically prepares cleaning and rinsing solution for the cleaning and rinsing of the dialyzer membrane as well as the dialyzate and blood flow path means, to provide a system which is so simplified in terms of automatic operation that it may be usable for daily dialysis at home.Type: GrantFiled: August 21, 1991Date of Patent: August 9, 1994Inventor: Zbylut J. Twardowski
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Patent number: 5209723Abstract: A multiple lumen, intravenous catheter for hemodialysis or the like defines a distal end portion in which at least a pair of the catheter lumens each communicates with the exterior through aperture means. By this invention the aperture means of one of the lumens defines a first port at essentially the distal catheter end, and the aperture means of the other of the lumens defines a second port spaced proximally along the catheter from the distal end and first port. The second port is positioned to face radially inwardly to at least a slight degree to avoid engagement of the wall of the blood vessel that the catheter occupies. Additionally, the tip of the catheter distal of the second port is preferably of substantially helically shape, being sized to assist in keeping the second port away from the blood vessel wall. As another feature, the catheter may be angled in its as-manufactured, unstressed condition to avoid pressing by elastic memory against internal blood vessel walls.Type: GrantFiled: October 8, 1991Date of Patent: May 11, 1993Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, John C. Van Stone, W. Kirt Nichols
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Patent number: 5171227Abstract: A peritoneal dialysis catheter comprises a distal tubular section and a proximal tubular section, connected together by a nonintegral tubular connector so that the respective sections are connected together in sealed flow relation. Such a catheter may be surgically implanted in the peritoneal cavity, extending to the chest of the patient with an end thereof protruding from the chest. The respective ends of the catheter section may be connected to each other through the tubular connector as the tubular sections are surgically implanted, and typically after such implantation is substantially complete.Type: GrantFiled: April 16, 1991Date of Patent: December 15, 1992Assignee: The Curators of the University of MissouriInventors: Zbylut J. Twardowski, Ramesh Khanna, W. Kirt Nichols, Karl D. Nolph
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Patent number: 4772269Abstract: A peritoneal catheter comprises a flexible catheter tube carrying porous cuff means to facilitate permanent securance of the catheter to the abdominal wall. The catheter tube defines, in its natural, unstressed condition, a bent segment adjacent the porous cuff means. This permits the catheter to be mounted in a tunnel formed through the abdominal wall in relatively unstressed configuration with both ends pointing downwardly.Type: GrantFiled: February 11, 1987Date of Patent: September 20, 1988Assignee: Curators of the University of MissouriInventors: Zbylut J. Twardowski, Karl D. Nolph
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Patent number: 4687471Abstract: A peritoneal catheter comprises a flexible catheter tube carrying porous cuff means to facilitate permanent securance of the catheter to the abdominal wall. The catheter tube defines, in its natural, unstressed condition, a bent segment adjacent the porous cuff means. This permits the catheter to be mounted in a tunnel formed through the abdominal wall in relatively unstressed configuration, with both ends pointing downwardly toward the feet of the patient. In one embodiment, the catheter includes a flange extending circumferentially outwardly of the catheter tube adjacent to the porous cuff means. The flange extends at a nonperpendicular angle relative to the axis of the catheter tube, and the slope of the flange extends transverse the direction of the bent segment. The angled flange, when sutured to the posterior rectus sheath, maintains the catheter tube in the desired tunnel direction within the abdominal wall, with the distal end of the catheter tube pointed properly downwardly toward the pelvic cavity.Type: GrantFiled: February 6, 1986Date of Patent: August 18, 1987Assignee: Curators of the University of MissouriInventors: Zbylut J. Twardowski, Karl D. Nolph, Ramesh Khanna
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Patent number: 4604379Abstract: Peritoneal dialysis solution may have an osmotic agent as a partial or complete substitute to the conventional dextrose. The osmotic agent is gelatin chemically cross-linked to suppress gelation.Type: GrantFiled: June 18, 1984Date of Patent: August 5, 1986Assignee: Curators of the University of MissouriInventors: Zbylut J. Twardowski, Karl D. Nolph