Hemofiltration system

{
  "publication_number": "US2001037079A1",
  "country": "US",
  "kind": "A1",
  "title": "Hemofiltration system",
  "abstract": "A hemofiltration system and method is provided that allows for high flow rate, accurate determination of net fluid withdrawal from or addition to a patient, and simple and reliable home operation. A removable, disposable assembly includes a filter housing and pump member including one or more fluid conduits mounted against the pump member, when the disposable filter/pump member assembly is attached to the treatment system, a pump roller mechanism associated with the system actuates the conduits mounted against the pump member. A disposable waste receptacle and fluid replacement (infusate) reservoir can be provided as an integral part of the disposable filter/pump member assembly.",
  "claims": [
    "1. A method for hemofiltration, comprising the steps of: withdrawing blood through a blood withdrawal line at a rate of at least 300 ml/min.; passing the blood through a filter to remove waste; and passing the filtered blood through a blood return line and into the patient, wherein blood is withdrawn from and returned to the patient continuously for about 1.5 hours, and wherein the ratio of the clearance rate to blood flow rate is at least 100:400. 2. The method of claim 1, further comprising the step of repeating the procedure at least four times per week. 3. The method of claim 1, wherein the filter is disposable. 4. The method of claim 1, wherein the blood withdrawal line, the filter, and the blood return line are pre-attached. 5. The method of claim 1, wherein an amount of replacement fluid is added to the blood, and wherein the amount is determined by gravimetric balancing of the replacement fluid and the waste. 6. The method of claim 1, further comprising the step of repeating the procedure at least daily. 7. The method of claim 1, wherein the procedure is conducted at home. 8. The method of claim 5, wherein the amount of the replacement fluid is approximately 9-13 liters. 9. The method of claim 5, wherein the replacement fluid is added to the blood after filtration. 10. The method of claim 1, further comprising the step of repeating the procedure for more than one week. 11. The method of claim 1, further comprising the steps of connecting the blood withdrawal line to the patient and connecting the blood return line to the patient. 12. The method of claim 11, wherein the blood withdrawal line and the blood return line are connected to the patient through a subcutaneous port. 13. The method of claim 1, further comprising the steps of: pumping the withdrawn blood with a pump at a predetermined blood flow rate; measuring the actual blood flow rate delivered by the pump; comparing the actual blood flow rate with the predetermined blood flow rate; and activating an alarm when the difference between the actual blood flow rate with the predetermined blood flow rate exceeds a predetermined value. 14. The method of claim 1, wherein the blood withdrawal line and the blood return line are in registry with a peristaltic pump. 15. The method of claim 1, wherein at least one of the blood withdrawal line and the blood return line further comprises a leak detector. 16. The method of claim 5, wherein replacement fluid is delivered through a replacement fluid line, and wherein the replacement fluid line further comprises an ultrasonic detector to indicate when replacement fluid is empty."
  ],
  "description_excerpt": "This is a division of U.S. application Ser. No. 08/800,881, filed Feb. 14, 1997, which is incorporated herein by reference in its entirety. [0001]\n\nThe present invention relates generally to a man-made apparatus that substitutes for natural kidney function, and more particularly to a compact, easy-to-use hemofiltration system equipped to maintain accurate net fluid volume change in a patient, and designed and constructed to be usable repeatedly in a patient's home. [0002]\n\nLoss of human renal function, for example due to kidney disease, affects hundreds of thousands of people worldwide. In the past, chronic renal failure has meant almost certain death. More recently, renal failure is treatable by kidney transplant and/or less-physiologically traumatic procedures such as hemodialysis or hemofiltration. Existing hemodialysis and hemofiltration systems operate by continuously withdrawing blood from a patient, treating the blood to remove waste, and continuously re-introducing treated blood into the patient. Hemodialysis operates by bringing blood into contact with one side of a semi-permeable membrane while a dialysis solution (dialysate) is brought into contact with the other side of the membrane. Uremic toxins diffuse out of the blood, through the semi-permeable membrane due to the concentration gradient across the membrane, and into the dialysate. Hemofiltration operates by passing the blood through a filter to remove waste. [0003]\n\nMost man-made renal function systems are not designed for convenient home use.",
  "cpc": [
    "A61M 39/0208",
    "A61M 1/3448",
    "A61M 1/3451",
    "A61M 1/36225",
    "A61M 1/3639",
    "A61M 1/367"
  ],
  "ipc": [
    "A61M 1/34",
    "A61M 39/02"
  ],
  "inventors": [
    "Jeffrey Burbank",
    "Charles Finch",
    "James Brugger"
  ],
  "filing_date": "2001-06-27",
  "publication_date": "2001-11-01",
  "priority_date": "1997-02-14",
  "application_number": "US-89423601-A",
  "family_id": "25179621",
  "cited_by_count": 200,
  "citations": [
    "US4661246A",
    "US5041098A",
    "US5211849A",
    "US5211849B1",
    "US5536412A",
    "US5730712A"
  ]
}