EP-4735073-A1 - HEMODIALYSIS SYSTEM WITH VARIABLE DIALYSATE FLOW RATE

Abstract

A portable hemodialysis system is provided including a dialyzer, a closed loop blood flow path, a closed loop dialysate flow path, a blood pump, and a pair of dialysate pumps. A processor controls the flow of blood through the blood flow path, and the processor controls the flow of dialysate through the dialysate flow path. In addition, the processor stores a preprogrammed patient treatment plan wherein the flow rate of the dialysate through the dialysate flow path reduces throughout the patient's treatment to maximize the amount of urea removed by the sorbent filter. In alternative embodiments, the processor stores a patient treatment plan wherein the dialysate flow rate increases throughout the patient's treatment. In still alternative embodiments, the processor stores a patient treatment plan wherein the flow rate of the dialysate through the dialysate flow path both increases and decreases throughout the patient's treatment.

Inventors

• BORILLO, Brandon
• CHEN, TZU TUNG
• POPPE, CLAYTON

Assignees

• Diality Inc.

Dates

Publication Date

20260506

Application Date

20240731

Claims (7)

1. 1. A hemodialysis system with variable flow rate comprising: a machine housing; an arterial blood line for connecting to a patient’s artery for collecting blood from a patient; a venous blood line for connecting to a patient’s vein for returning blood to a patient; a dialyzer; a blood flow path connected to said arterial blood line and said venous blood line for transporting blood from a patient to said dialyzer and back to a patient; a reservoir for storing dialysate; a dialysate flow path, isolated from the blood flow path, connected to said reservoir and said dialyzer for transporting dialysate from said reservoir to said dialyzer; at least one dialysate pump for pumping dialysate through said dialysate flow path; a blood pump for pumping blood through said blood flow path; a dialysate flow sensor in said dialysate flow path which measures the flow rate of dialysate through said dialysate flow path; a control processor connected to said dialysate flow sensor and said at least one dialysate pump, said control processor possessing memory for storing a patient treatment plan by which a patient is treated, said patient treatment plan includes dialysate flow rates during a patient’s treatment wherein the dialysate flow rates increase over the time period “T(total)” for treating a patient.
2. 2. A hemodialysis system with variable flow rate of claim 1 wherein said dialysate flow rates include a high flow rate and a low flow rate, and wherein low flow rate is less than 75% of said high flow rate.
3. 3. A hemodialysis system with variable flow rate of claim 1 wherein said patient treatment plan includes increasing the dialysate flow rate in a linear manner.
4. 4. A hemodialysis system with variable flow rate of claim 1 wherein said dialysate flow rates increase incrementally in a stepped manner, and include a high flow rate and a low flow rate.
5. 5. A hemodialysis system with variable flow rate of claim 1 wherein dialysate flow rates include a high flow rate between 400 to 800 ml/min and a low flow rate between 100 to 400 ml/min.
6. 6. A hemodialysis system with variable flow rate of claim 1 wherein said control processor causes said dialysate pump to pump dialysate through said dialysate flow path at between 400 to 800 ml/min for at least 0.5 hours and said control processor causes said dialysate pump to pump dialysate through said dialysate flow path at between 100 to 400 ml/min for at least 0.5 hours.
7. 7. A hemodialysis system with variable flow rate of claim 1 wherein said patient treatment plan includes dialysate flow rates wherein the dialysate flow rates increase over the time period “T(total)” for treating a patient and said patient treatment plan includes dialysate flow rates during a patient’s treatment wherein the dialysate flow rates decrease over the time period “T(total)” for treating a patient.

Description

HEMODIALYSIS SYSTEM WITH VARIABLE DIALYSATE FLOW RATE CROSS-REFERENCE TO RELATED APPLICATIONS [001] The present application claims priority to United States Patent Application Serial No. 18/228,491, filed July 31, 2023, which is incorporated herein by reference. BACKGROUND OF THE INVENTION [002] The present invention relates to an artificial kidney system for use in providing dialysis. More particularly, the present invention is directed to a hemodialysis system. [003] Applicant hereby incorporates herein by reference any and all patents and published patent applications cited or referred to in this application. [004] Hemodialysis is a medical procedure that is used to achieve the extracorporeal removal of waste products including creatine, urea, and free water from a patient’s blood involving the diffusion of solutes across a semipermeable membrane. Failure to properly remove these waste products can result in renal failure. [005] During hemodialysis, the patient’s blood is removed by an arterial line, treated by a dialysis machine, and returned to the body by a venous line. The dialysis machine includes a dialyzer containing a large number of hollow fibers forming a semipermeable membrane through which the blood is transported. In addition, the dialysis machine utilizes a dialysate liquid, containing the proper amounts of electrolytes and other essential constituents (such as glucose), that is also pumped through the dialyzer. [006] Typically, dialysate is prepared by mixing water with appropriate proportions of an acid concentrate and a bicarbonate concentrate. Preferably, the acid and the bicarbonate concentrate are separated until the final mixing right before use in the dialyzer as the calcium and magnesium in the acid concentrate will precipitate out when in contact with the high bicarbonate level in the bicarbonate concentrate. The dialysate may also include appropriate levels of sodium, potassium, chloride, and glucose. [007] The dialysis process across the membrane is achieved by a combination of diffusion and convection. The diffusion entails the migration of molecules by random motion from regions of high concentration to regions of low concentration. Meanwhile, convection entails the movement of solute typically in response to a difference in hydrostatic pressure. The fibers forming the semipermeable membrane separate the blood plasma from the dialysate and provide a large surface area for diffusion to take place which allows waste, including urea, potassium and phosphate, to permeate into the dialysate while preventing the transfer of larger molecules such as blood cells, polypeptides, and certain proteins into the dialysate. [008] Typically, the dialysate flows in the opposite direction to blood flow in the extracorporeal circuit. The countercurrent flow maintains the concentration gradient across the semipermeable membrane so as to increase the efficiency of the dialysis. In some instances, hemodialysis may provide for fluid removal, also referred to as ultrafiltration. Ultrafiltration is commonly accomplished by lowering the hydrostatic pressure of the dialysate compartment of a dialyzer, thus allowing water containing dissolved solutes, including electrolytes and other permeable substances, to move across the membrane from the blood plasma to the dialysate. In rarer circumstances, fluid in the dialysate flow path portion of the dialyzer is higher than the blood flow portion, causing fluid to move from the dialysis flow path to the blood flow path. This is commonly referred to as reverse ultrafiltration. Since ultrafiltration and reverse ultrafiltration can increase the risks to a patient, ultrafiltration and reverse ultrafiltration are typically conducted while supervised by highly trained medical personnel. [009] Unfortunately, hemodialysis suffers from numerous drawbacks. An arteriovenous fistula is the most commonly recognized access point. To create a fistula, a doctor joins an artery and a vein together. Since this process bypasses the patient’s capillaries, blood flows rapidly. For each dialysis session, the fistula must be punctured with large needles to deliver blood into, and return blood from, the dialyzer. Typically, this procedure is done three times a week, for 3 - 4 hours at an out-patient facility. To a lesser extent, patients conduct hemodialysis at home. Home dialysis is typically done for two hours, six days a week. However, home hemodialysis requires more frequent treatment. [010] Home hemodialysis suffers from still additional disadvantages. Current home dialysis systems are big, complicated, intimidating, and difficult to operate. The equipment requires significant training. Home hemodialysis systems are currently too large to be portable, thereby preventing hemodialysis patients from traveling. Home hemodialysis systems are expensive and require a high initial monetary investment, particularly compared to in-center hemodialysis where patients are not required to