Patent US4500309A successfully refreshed from Google Patents.
US4500309A
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Method for regional anticoagulation during extracorporeal dialysis
Assignee: KANSAS UNIVERSITY ENDOWNMENT ASSOCIATION A CORP OF KS
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Filing: 1982-05-07
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Granted: 1985-02-19
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Expires: 2002-05-07
Abstract
Abstract An improved hemodialysis method (which may optionally include a hemoperfusion step) including regional extracorporeal citrate anticoagulation is disclosed which permits complete elimination of conventional heparin treatment and possible consequent medical complications from heparin use. The method preferably comprises removing blood from a patient at a level of at least about 80 milliliters per minute, infusing citrate anticoagulant into the blood at a level of up to about 10 millimoles of citrate anion per liter of blood, treating the blood (e.g., by dialysis and hemoperfusion if desired), thereafter infusing a calcium compound into the blood to restore proper calcium ion level and coagulative properties, and returning the blood to the patient. A calcium-free acetate or bicarbonate dialysate is advantageously employed. A charcoal perfusion filter can optionally be used in conjunction with the dialyzer apparatus.
Inventors
- 👤 Dennis A. Diederich
- 👤 Thomas B. Wiegmann
- 👤 Robert V. Pinnick
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 19:06
CPC Classifications
A; A61; A61M; A61M1/00; A61M1/36; A61M1/3672; A61M1/34; A61M1/342; A61M1/3424; A61M1/3437; A61M1/3455; A61M1/3458; A61M1/3675; Y; Y10; Y10S; Y10S128/00; Y10S128/03
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
124 words
A blood treatment method comprising the steps of: withdrawing blood from a patient at a rate of from about 100 to 300 milliliters per minute; preventing the coagulation of said withdrawn blood by infusing an anticoagulant substance into the blood, said anticoagulant substance consisting essentially of citrate anion and being infused at a level to provide up to about 10 millimoles of citrate anion per liter of blood; passing the withdrawn, citrate-infused blood through treatment apparatus concurrently with a toxin-removing dialysate for removing toxins from the blood; after passage of said blood through said apparatus, infusing into said blood a calcium compound in an amount to achieve a desired level of calcium ion in said blood; and returning the calcium-infused blood to said patient.
Claim 2
Dependent Claim
124 words
A blood treatment method comprising the steps of: withdrawing blood from a patient at a rate of from about 100 to 300 milliliters per minute; preventing the coagulation of said withdrawn blood by infusing an anticoagulant substance into the blood, said anticoagulant substance consisting essentially of citrate anion and being infused at a level to provide up to about 10 millimoles of citrate anion per liter of blood; passing the withdrawn, citrate-infused blood through treatment apparatus concurrently with a toxin-removing dialysate for removing toxins from the blood; after passage of said blood through said apparatus, infusing into said blood a calcium compound in an amount to achieve a desired level of calcium ion in said blood; and returning the calcium-infused blood to said patient.
Claim 3
Dependent Claim
21 words
The method as set forth in claim 1, said blood removal rate being from about 150 to 250 milliliters per minute.
Claim 4
Dependent Claim
14 words
The method as set forth in claim 1, said dialysate being essentially calcium free.
Claim 5
Dependent Claim
18 words
The method as set forth in claim 1, said dialysate being selected from the acetate and bicarbonate-based dialysates.
Claim 6
Dependent Claim
30 words
The method as set forth in claim 1, said anticoagulant being infused at a level to infuse from about 2 to 8 millimoles of citrate anion per liter of blood.
Claim 7
Dependent Claim
30 words
The method as set forth in claim 5, said anticoagulant being infused at a level to infuse from about 2 to 6 millimoles of citrate anion per liter of blood.
Claim 8
Dependent Claim
15 words
The method as set forth in claim 1, said anticoagulant being trisodium citrate.2H 2 O.
Claim 9
Dependent Claim
19 words
The method as set forth in claim 7, said trisodium citrate.2H 2 O being the sole anticoagulant substance employed.
Claim 10
Dependent Claim
33 words
The method as set forth in claim 1, said calcium ion being added to give a resultant blood level of calcium ion from about 8 to 12 milligrams per 100 milliliters of blood.
Claim 11
Dependent Claim
17 words
The method as set forth in claim 1, said anticoagulant being nearly isotonic relative to said blood.
Claim 12
Dependent Claim
18 words
The method as set forth in claim 1, including the step of passing said blood through filtering means.
Claim 13
Dependent Claim
151 words
A blood treatment method comprising the steps of: withdrawing blood from a human patient at a rate of from about 100 to 300 milliliters per minute; preventing the coagulation of said withdrawn blood by infusing an anticoagulant substance into the blood, said anticoagulant substance consisting essentially of trisodium citrate.2H 2 O which is only isotonic relative to said blood, said anticoagulant being infused at a level to provide up to about 10 millimoles of citrate anion per liter of blood; passing the withdrawn, citrate-infused blood through treatment apparatus concurrently with a calcium-free toxin-removing dialysate for removing toxins from the blood; after passage of said blood through said apparatus, infusing into said blood a calcium compound in an amount to achieve a desired level of calcium ion in said blood of from about 8 to 12 milligrams calcium ion per 100 milliliters of blood; and returning the calcium-infused blood to said patient.
Claim 14
Dependent Claim
151 words
A blood treatment method comprising the steps of: withdrawing blood from a human patient at a rate of from about 100 to 300 milliliters per minute; preventing the coagulation of said withdrawn blood by infusing an anticoagulant substance into the blood, said anticoagulant substance consisting essentially of trisodium citrate.2H 2 O which is only isotonic relative to said blood, said anticoagulant being infused at a level to provide up to about 10 millimoles of citrate anion per liter of blood; passing the withdrawn, citrate-infused blood through treatment apparatus concurrently with a calcium-free toxin-removing dialysate for removing toxins from the blood; after passage of said blood through said apparatus, infusing into said blood a calcium compound in an amount to achieve a desired level of calcium ion in said blood of from about 8 to 12 milligrams calcium ion per 100 milliliters of blood; and returning the calcium-infused blood to said patient.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-02-19 | 1988-08-20 | 1989-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-02-19 | 1992-08-20 | 1993-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-02-19 | 1996-08-20 | 1997-02-19 | $7700.00 | Window Closed / Lapsed |