US-12623008-B2 - Apparatus for extracorporeal blood treatment

US12623008B2US 12623008 B2US12623008 B2US 12623008B2US-12623008-B2

Abstract

An apparatus for extracorporeal blood treatment comprising a filtration unit, a blood circuit comprising a blood withdrawal line and a blood return line, and a fluid circuit. The fluid circuit comprises at least one or more water inlet ducts for receiving water, a dialysis preparation assembly comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of a dialysis fluid, wherein the water inlet duct is configured to provide water to the dialysis preparation assembly for preparing said mixed solution of dialysis fluid. The fluid circuit further comprises an infusion preparation assembly comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of an infusion fluid, wherein the water inlet duct is configured to provide water to the infusion preparation assembly for preparing said mixed solution of infusion fluid.

Inventors

Mauro Suffritti
Stefano Ganzerli
Fabrizio Molducci
Paola Crivellari
Alfonso Vollono
Marisa Torrini
Sonja Bellini
Mauro Gusella

Assignees

GAMBRO LUNDIA AB

Dates

Publication Date: 20260512
Application Date: 20210517
Priority Date: 20200529

Claims (20)

1 . An apparatus for extracorporeal blood treatment comprising: a filtration unit having a primary chamber and a secondary chamber separated by a semi-permeable membrane; a blood circuit comprising: a blood withdrawal line extending between a first end connected to an inlet of the primary chamber and a second end for connection to a patient, and a blood return line extending between a first end connected to an outlet of the primary chamber and a second end for connection to said patient; a fluid circuit comprising: one or more water inlet ducts for receiving water, a dialysis preparation assembly comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of dialysis fluid, at least one of said one or more water inlet ducts to provide water to the dialysis preparation assembly for preparing said mixed solution of dialysis fluid, and an infusion preparation assembly, separate and distinct from the dialysis preparation assembly, comprising one or more concentrated sources housing a respective concentrate solution and configured to prepare a mixed solution of infusion fluid, at least one of said one or more water inlet ducts configured to provide water to the infusion preparation assembly for preparing said mixed solution of infusion fluid; intercepting elements arranged and operative at least along the fluid circuit and configured to move between a closed position, wherein a fluid passage is interdicted, and an open position wherein fluid passage is allowed; and a control unit configured to control one or more of said intercepting elements between the closed position and the open position to determine a fluid flow configuration defining different fluid paths, said fluid flow configuration comprising a main operative mode wherein: at least one of said one or more water inlet ducts is configured to provide water to the dialysis preparation assembly for preparing said mixed solution of dialysis fluid, wherein the mixed solution of dialysis fluid is suppliable to an inlet of the secondary chamber of the filtration unit, and at least one of said one or more water inlet ducts is configured to provide water to the infusion preparation assembly for preparing said mixed solution of infusion fluid, wherein the mixed solution of infusion fluid is infusible through an infusion access point into the blood circuit, wherein said fluid flow configuration comprises at least a second operative mode in which the dialysis preparation assembly and the infusion preparation assembly cooperate to prepare an auxiliary mixed solution of dialysis fluid different from the mixed solution of dialysis fluid and from the mixed solution of infusion fluid.
2 . The apparatus of claim 1 , further comprising: a supply line extending between an outlet of the dialysis preparation assembly and the inlet of the secondary chamber of the filtration unit, and an infusion line extending between an outlet of the infusion preparation assembly and the infusion access point of the blood circuit, wherein in the main operative mode: the outlet of the dialysis preparation assembly is fluidly connected to the inlet of the secondary chamber of the filtration unit, the outlet of the infusion preparation assembly is fluidly connected to the blood circuit, and the one or more water inlet ducts being configured to supply water independently and, through different tube segments, directly to both the dialysis preparation assembly and the infusion preparation assembly; wherein the control unit is configured to control the dialysis preparation assembly and the infusion preparation assembly to respectively prepare the mixed solution of dialysis fluid and the mixed solution of infusion fluid so that the mixed solution of dialysis fluid is different in composition from the mixed solution of infusion fluid, the dialysis fluid being different from the infusion fluid due to: a nature of one or more solutes; and/or a concentration of one or more solutes; and wherein the mixed solution of dialysis fluid is supplied to the inlet of the secondary chamber of the filtration unit simultaneously with an infusion of the mixed solution of infusion fluid into the blood circuit.
3 . The apparatus of claim 2 , wherein the infusion line extends between the outlet of the infusion preparation assembly and the infusion access point placed at the blood return line of the blood circuit, the outlet of the infusion preparation assembly being fluidly connected to the blood return line of the blood circuit.
4 . The apparatus of claim 1 , wherein in the second operative mode: the mixed solution of infusion fluid and the mixed solution of dialysis fluid are mixed so as to define the auxiliary mixed solution of dialysis fluid flowing in a supply line, wherein the auxiliary mixed solution of dialysis fluid is suppliable to the inlet of the secondary chamber of the filtration unit and/or is infusible into the blood circuit, and wherein, in said second operative mode, the dialysis preparation assembly is fluidly connected in series, upstream or downstream, with respect to the infusion preparation assembly, and a first preparation line is fluidly connected in series with respect to a second preparation line.
5 . The apparatus of claim 1 , wherein in the main operative mode, one of concentrated sources of the dialysis preparation assembly comprises concentrated electrolytes, including sodium, calcium and potassium, and another one of the concentrated sources of the dialysis preparation assembly comprises concentrated electrolytes, including sodium and calcium.
6 . The apparatus of claim 5 , wherein a potassium concentration in the one of the concentrated sources is different from the potassium concentration in another one of the concentrated sources; and wherein concentrations of other electrolytes different from potassium are equal in the concentrated sources and in the another one of the one or more concentrated sources.
7 . The apparatus of claim 1 , wherein at least one concentrated solution housed into the one or more concentrated sources of the infusion preparation assembly comprises a buffer substance from the group including bicarbonate, citrate, lactate and acetate; and wherein in the main operative mode, the at least one concentrated solution housed into the one or more concentrated sources of the infusion preparation assembly comprises bicarbonate.
8 . The apparatus of claim 4 , comprising: a first conductivity sensor arranged in the dialysis preparation assembly along the first preparation line downstream with respect to the one or more concentrated sources, the first conductivity sensor configured to provide a first signal representative of an electrical conductivity of the mixed solution of dialysis fluid, and of an electrical conductivity of the auxiliary mixed solution of dialysis fluid, wherein the control unit is configured to receive the first signal representative of the electrical conductivity to determine an actual conductivity and to compare the actual conductivity to a target conductivity, the control unit driving the dialysis preparation assembly to reduce a difference between the actual conductivity and the target conductivity; and a second conductivity sensor arranged in the infusion preparation assembly along the second preparation line downstream with respect to the one or more concentrated sources of the infusion preparation assembly, the second conductivity sensor configured to provide a second signal representative of an electrical conductivity of the mixed solution of infusion fluid, wherein the control unit is configured to receive the second signal representative of the electrical conductivity to determine the actual conductivity and to compare the actual conductivity to a target conductivity, the control unit driving the infusion preparation assembly to reduce the difference between the actual conductivity and the target conductivity.
9 . The apparatus of claim 1 , wherein the fluid circuit comprises a bridging line interposed in fluid communication between an infusion line and a supply line, wherein the intercepting elements comprise one or more of: a bridging valve arranged along the bridging line to allow or interdict fluid flow between the infusion line and the supply line; an infusion valve arranged along the infusion line to allow or prevent the infusion fluid to flow towards the infusion access point; and a first inlet valve arranged along a first preparation line, said first inlet valve being interposed between the one or more water inlet duct and the one or more concentrated sources of the dialysis preparation assembly; or a second inlet valve arranged along a second preparation line, said second inlet valve being interposed between the water inlet duct and the one or more concentrated sources of the infusion preparation assembly.
10 . The apparatus of claim 9 , wherein in a main operation mode: the first and second inlet valves of the first and second preparation lines are in the open position; the bridging valve is in the closed position; a dialysis fluid pump determines dialysis fluid flow towards the secondary chamber of the filtration unit; and an infusion pump of the infusion line determines infusion fluid flow towards the infusion access point of the blood circuit or directly in a vascular access of the patient; and wherein in a second operation mode: the inlet valve of the first preparation line is in the closed position; the inlet valve of the second preparation line is in the open position; the bridging valve is in the open position; the dialysis fluid pump determines the dialysis fluid flow towards the secondary chamber of the filtration unit; and and the infusion pump of the infusion line is not active.
11 . The apparatus of claim 1 , wherein the fluid circuit includes: a water inlet duct for receiving water, said water inlet duct branching into a water line to feed water directly to the infusion preparation assembly and into a water branch to feed water directly to the dialysis preparation assembly, wherein the intercepting elements comprise one or more valves to allow or prevent water from flowing in the water line and/or in the water branch; a bridging line fluidly connecting an outlet of the infusion preparation assembly with an inlet to the dialysis preparation assembly, wherein the intercepting elements comprise one or more valves to allow or prevent water from flowing in the bridging line; an infusion line connected to an outlet of the infusion preparation assembly routing the infusion fluid to the blood circuit, the infusion line including an on-line port and a tube portion connecting the outlet of the infusion preparation assembly to the on-line port, wherein the tube portion connecting the outlet of the infusion preparation assembly to the on-line port includes an infusion pump; a supply line connected to an outlet of the dialysis preparation assembly routing the infusion fluid to the filtration unit; and a connecting line fluidly connecting the infusion line and the supply line, wherein the intercepting elements comprise one or more valves to allow or prevent fluid from flowing into the connecting line.
12 . The apparatus of claim 11 , wherein in the main operation mode, the control unit is configured to drive: the one or more valves to allow water flow towards both (i) the dialysis preparation assembly through the water branch and (ii) the infusion preparation assembly through the water line; the one or more valves to prevent fluid flow through the bridging line between the outlet of the infusion preparation assembly and the inlet of the dialysis fluid preparation assembly; and the one or more valves in the connecting line to prevent fluid flow through the connecting line between the infusion line and the supply line.
13 . The apparatus of claim 11 , wherein the tube portion connecting the outlet of the infusion preparation assembly to the on-line port includes at least one infusion ultrafilter placed between a connecting line fluidly connecting the tube portion with an outlet of the dialysis preparation assembly and the on-line port, and/or wherein the on-line port is an access placed on an external portion of a cabinet of the apparatus, the on-line port being configured for a connection of a disposable tubing directing fluid to the blood circuit.
14 . The apparatus of claim 1 , wherein the fluid circuit comprises a joining tubing fluidly connecting a supply line to an infusion line downstream of an infusion pump placed on the infusion line and connecting the supply line downstream of an infusion ultrafilter, the intercepting elements comprising one or more valves to allow or prevent fluid from flowing in the joining tubing, wherein in a main operation mode, the control unit drives the one or more valves to prevent fluid flow through the joining tubing between the infusion line and the supply line, and wherein the joining tubing connects the supply line to an on-line port of the infusion line.
15 . The apparatus of claim 1 , wherein the fluid circuit includes a water inlet duct for receiving water, said water inlet duct branching into a water line to feed water directly to the infusion preparation assembly and into a water branch to feed water directly to the dialysis preparation assembly, wherein the fluid circuit comprises an inlet flow meter placed on the water inlet duct upstream the branching and an effluent line flow meter on an effluent line, and wherein at least in a main operation mode, the control unit is configured to: receive or calculate a set ultrafiltration rate to be achieved during the extracorporeal blood treatment; and drive the apparatus to achieve the set ultrafiltration rate based on a difference between an effluent flow rate, measured with the effluent line flow meter, and a sum of an infusion flow rate and a dialysis flow rate, measured with the inlet flow meter.
16 . The apparatus of claim 1 , wherein the fluid circuit comprises a supply line flow meter on the supply line, an infusion line flow meter on the infusion line and an effluent line flow meter on an effluent line, wherein, in a main operating mode, the control unit receive signals from the supply line flow meter, the infusion line flow meter and the effluent line flow meter to control an ultrafiltration rate through the filtration unit, wherein the control unit receives or calculates a set ultrafiltration rate to be achieved during the extracorporeal blood treatment and drives the apparatus to achieve the set ultrafiltration rate based on the signals received from the supply line flow meter, the infusion line flow meter and the effluent line flow meter based on a difference between an effluent flow rate and the sum of the infusion flow rate, measured with the infusion line flow meter, and a dialysis flow rate.
17 . The apparatus of claim 2 , wherein the control unit is configured to control the one or more of the intercepting elements between the open position and the closed position to allow or prevent the infusion line to be in fluid communication with the supply line.
18 . The apparatus of claim 2 , wherein the fluid circuit defines a fluid line net comprising the dialysis preparation assembly, the infusion preparation assembly, the infusion line, the supply line and the intercepting elements, and wherein the dialysis preparation assembly, the infusion preparation assembly, the infusion line, and the supply line are in fluid communication with each other through said fluid line net and fluidly connectable with each other based on the open position or the closed position of the intercepting elements.
19 . The apparatus of claim 1 , wherein the control unit is configured to control the one or more of said intercepting elements between the open position and the closed position to allow or prevent the dialysis preparation assembly to be in fluid communication with the infusion preparation assembly, and to allow or prevent the mixed solution of dialysis fluid prepared in the dialysis preparation assembly to be in fluid communication with the infusion preparation assembly, or the mixed solution of infusion fluid prepared in the infusion preparation assembly to be in fluid communication with the dialysis preparation assembly.
20 . The apparatus of claim 1 , wherein the dialysis preparation assembly and the infusion preparation assembly are in fluid communication with each other through fluid lines defining a fluid line net comprising the intercepting elements, the control unit being configured to control the one or more of said intercepting elements between the open position and the closed position to define two or more fluid paths for the mixed solution of dialysis fluid and for the mixed solution of infusion fluid.

Description

PRIORITY CLAIM The present application is a National Phase of International Application No. PCT/EP2021/062970, filed May 17, 2021, which claims priority to EP Application Serial No. 20177592.1, filed May 29, 2020, the entire contents of each of which are incorporated herein by reference and relied upon. FIELD OF THE INVENTION The present invention relates to an apparatus for extracorporeal blood treatment configured, and a method aimed, to prepare a mixed solution of dialysis fluid to be provided to a dialyzer and a mixed solution of infusion fluid to be infused into the blood circuit of a patient. Both the mixed solutions of dialysis fluid and infusion fluid are prepared by mixing a concentrate solution/s of a substance/s with water, the latter being provided from an on-line source. In one embodiment, the present invention may be used to deliver acetate-free biofiltration treatments with a constant or variable potassium management. BACKGROUND OF THE INVENTION The kidneys fulfil many functions, including the removal of water, the excretion of catabolites (or waste from the metabolism, for example urea and creatinine), the regulation of the concentration of the electrolytes in the blood (e.g. sodium, potassium, magnesium, calcium, bicarbonates, phosphates, chlorides) and the regulation of the acid/base equilibrium within the body, which is obtained in particular by the removal of weak acids and by the production of ammonium salts. In individuals who have lost the use of their kidneys, since these excretion and regulation mechanisms no longer work, the body accumulates water and waste from the metabolism and exhibits an excess of electrolytes. In order to overcome renal dysfunction, resort is conventionally made to a blood treatment involving extracorporeal circulation within a blood circuit through an exchanger having a semipermeable membrane (dialyzer) in which the patient's blood is circulated on one side of the membrane and a dialysis liquid, comprising the main electrolytes of the blood in concentrations close to those in the blood of a healthy subject, is circulated on the other side. The patient is connected to the extracorporeal blood circuit through a withdrawal (or arterial) and a return (or venous) line, the latter having respective needles at the end portions. A pressure difference is created between the two compartments of the dialyzer which are delimited by the semipermeable membrane, so that a fraction of the plasma fluid passes by ultrafiltration through the membrane into the compartment containing the dialysis liquid. The blood treatment which takes place in a dialyzer as regards waste from the metabolism and electrolytes results from two mechanisms of molecular transport through the membrane between the blood and the dialysis fluid. The dialysis fluid is prepared upstream of the dialyzer by mixing pure water with a plurality of predetermined substances, such as electrolytes, to be exchanged within the dialyzer with the patient's blood. Water comes from an inlet port receiving purified and de-ionized water (e.g., by reverse osmosis), to be subsequently further filtered within the apparatus so that a substantially endless water source is provided to the blood treatment apparatus. Treatment apparatuses configured to deliver hemofiltration or hemodiafiltration treatments also comprise an infusion line connected to the blood circuit of the dialysis disposable set: the infusion line may be used for infusing replacement fluid into the patient extracorporeal blood and/or to infuse one or more specific substances to control blood parameters. For example, a bicarbonate solution may be infused into the blood circuit for controlling blood acid-base balance of the patient during a dialysis treatment: a bag containing a bicarbonate liquid solution is usually provided to be connected to the blood circuit in order to allow a controlled infusion. For example, U.S. Pat. No. 5,578,223 discloses a dialysis apparatus wherein a fresh dialysis fluid not including any bicarbonate solution is routed towards the dialyzer (or alternatively into post infusion in the patient extracorporeal blood). A further post infusion line is provided for connection to an infusion solution contained in a respective bag. The infusion solution is a sodium bicarbonate solution. The apparatus control unit is configured to automatically regulate post infusion flow rate based on bicarbonate concentration in the infusion bag, desired concentration of bicarbonate into the patient and the effluent flow rate. During the extracorporeal blood treatment, the operators have to manage the bags, i.e. providing adequate installation on the apparatus scales, replacement of empty bags with new bags during treatment, handling of exhaust and new bags. Notably, new bicarbonate bags are somehow heavy (5/10 litres), which implies difficulties during installation on the machine scales: moreover, the liquid volume is limited, in order to reduce weight due to