US5032615A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous hemodialysis using citrate
Assignee: University of California
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Filing: 1989-10-31
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Granted: 1991-07-16
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Expires: 2009-10-31
Abstract
Abstract The present invention provides a method of preventing blood from clotting in a filter during continuous arteriovenous or venovenous hemodialysis on a patient comprising administering to the blood an amount of citrate sufficient to prevent clotting in the filter. The invention preferably utilizes a dialysate having a sodium and calcium concentration below that of normal blood and an alkali concentration sufficiently low to reduce or prevent alkalosis.
Inventors
- 👤 David M. Ward
- 👤 Ravindra L. Mehta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 18:20
CPC Classifications
A; A61; A61M; A61M1/00; A61M1/36; A61M1/3672; A61M1/14; A61M1/16; A61M1/1654; A61M1/34; A61M1/342; A61M1/3424; A61M1/3431; A61M1/3455; A61M1/3458; A61M1/3675
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
95 words
A method of preventing blood from clotting in a filter during continuous arteriovenous or venovenous hemodialysis on a patient comprising continuously administering to the blood which has been drawn from the patient and has not yet entered the filter an effective anti-clotting amount of sodium citrate sufficient to prevent clotting in the filter and a dialysate comprising sodium at a concentration between about 77 and 130 mEq/1, alkali at a concentration below about 25 mEq/1, calcium at a concentration below that of blood, and wherein the dialysate flow rate is less than about 6,000 ml/hr.
Claim 2
Independent Claim
95 words
A method of preventing blood from clotting in a filter during continuous arteriovenous or venovenous hemodialysis on a patient comprising continuously administering to the blood which has been drawn from the patient and has not yet entered the filter an effective anti-clotting amount of sodium citrate sufficient to prevent clotting in the filter and a dialysate comprising sodium at a concentration between about 77 and 130 mEq/1, alkali at a concentration below about 25 mEq/1, calcium at a concentration below that of blood, and wherein the dialysate flow rate is less than about 6,000 ml/hr.
Claim 3
Dependent Claim
18 words
The method of claim 1, wherein the sodium is at a concentration between about 97 and 117 mEq/1.
Claim 4
Dependent Claim
19 words
The method of claim 1, wherein the dialysate has an alkali concentration sufficiently low to reduce or prevent alkalosis.
Claim 5
Dependent Claim
14 words
The method of claim 1, wherein the alkali concentration is below about 15 mEq/1.
Claim 6
Dependent Claim
12 words
The method of claim 4, wherein the alkali concentration is essentially zero.
Claim 7
Dependent Claim
17 words
The method of claim 1, wherein the dialysate flow rate is between about 300 and 2,400 ml/hr.
Claim 8
Dependent Claim
14 words
The method of claim 6, wherein the dialysate flow rate is about 1000 ml/hr.
Claim 9
Dependent Claim
24 words
The method of claim 1, further comprising adding a therapeutically effective amount of an acid sufficient to reduce or prevent alkalosis in the patient.
Claim 10
Dependent Claim
22 words
The method of claim 8, wherein the acid is selected from the group consisting of hydrogen chloride, arginine hydrochloride, and ammonium chloride.
Claim 11
Dependent Claim
18 words
The method of claim 1, further comprising a dialysate with an osmolality greater or equal to normal blood.
Claim 12
Dependent Claim
10 words
The method of claim 10, wherein the dialysate contains dextrose.
Claim 13
Dependent Claim
20 words
The method of claim 1, further comprising administering a replacement solution having about the same sodium concentration as the blood.
Claim 14
Dependent Claim
13 words
The method of claim 1, wherein the dialysate calcium concentrate is essentially zero.
Claim 15
Dependent Claim
26 words
The method of claim 1, further comprising adding sufficient calcium either post-filter or directly to the patient to reduce or prevent citrate toxicity or diminish hypocalcemia.
Claim 16
Dependent Claim
28 words
A dialysate solution comprising a sodium concentration between about 77 and 130 mEq/1, a calcium concentration below that of blood, and an alkali concentration below about 25 mEq/1.
Claim 17
Dependent Claim
28 words
A dialysate solution comprising a sodium concentration between about 77 and 130 mEq/1, a calcium concentration below that of blood, and an alkali concentration below about 25 mEq/1.
Claim 18
Dependent Claim
15 words
The dialysate of claim 15, further comprising a glucose or dextrose concentration of about 2.5%.
Claim 19
Dependent Claim
14 words
The dialysate of claim 15, further comprising a magnesium concentration of about 1.5 mEq/1.
Claim 20
Dependent Claim
14 words
The dialysate of claim 15, further comprising a potassium concentration of about 4.0 mEq/1.
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) | 1994-07-15 | 1995-01-14 | 1995-07-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-15 | 1999-01-14 | 1999-07-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-15 | 2003-01-14 | 2003-07-16 | $7700.00 | Window Closed / Lapsed |