Method and apparatus for single pass hemodialysis with high flux membranes and controlled ultrafiltration
AssigneeRensselaer Polythechnic Institute
InventorD. Allen Zelman
Life of this patent
Estimating the term…
Abstract
Disclosed is a method of hemodialysis and a modification for existing hemodialyzers to facilitate use of the method. A highly porous membrane is utilized in a single pass hemodialysis system. The membrane is freely supported, such that it distends in use to maintain a constant transmembrane pressure over its entire surface. The modification to existing dialyzers includes the use of a highly porous membrane, in combination with a transmembrane pressure sensor, which controls the dialysate output flow to maintain a precise transmembrane pressure.
Claims5
A method of single pass hemodialysis for removal of metabolites from the blood of a patient including middle molecules of a size on the order of 300 to 2000 daltons, comprising the steps of:
- providing a single pass hemodialyzer with a freelymounted membrane having an ultrafiltration coefficient of at least 20 ml m.sup.-2 hr.sup.-1 mmHg.sup.-1 ;
- connecting said patient to said single-pass hemodialyzer in a conventional manner;
- and
- operating said hemodialyzer with a transmembrane pressure of between 0 and 30 mmHg to reduce ultrafiltration of the patient.
In a single-pass hemodialyzer for hemodialysis of a patient, said dialyzer including a freely-supported dialyzing membrane such that the patient's blood is circulated past one side of the membrane and a dialyzing solution is circulated past the other side of the membrane, there being a transmembrane pressure caused by the blood pressure exceeding the dialysate pressure, said improvement comprising:
- said membrane is a high flux membrane having an ultrafiltration coefficient of at least 20 ml m.sup.-2 hr.sup.-1 mmHg.sup.-1 and a reflection coefficient of about zero for solutes having a molecular weight up to 2000 daltons;
- and
- means for maintaining the transmembrane pressure at between 0 and 30 mmHg at least one point on the membrane.
Dependencies are inferred from the claim text.