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US 12,128,164 B2Granted
Apparatus for performing an extracorporeal blood treatment
AssigneeGambro Lundia AB
InventorAnders Nilsson
Life of this patent
Estimating the term…
Abstract
An extracorporeal blood treatment apparatus is provided comprising a filtration unit connected to a blood circuit and to a dialysate circuit; a control unit is configured for calculating a sodium concentration value for the blood; the estimation of the sodium concentration includes the sub-step of calculating the sodium concentration value as an algebraic sum of a main contribution term based on the isoconductive sodium concentrate and of an offset contribution term based on a concentration of at least a substance in the dialysis fluid chosen in the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate and phosphate.
Claims21
A method of estimating a blood parameter in an apparatus for extracorporeal blood treatment, the apparatus comprising:
- a filtration unit having a primary chamber and a secondary chamber separated by a semi-permeable membrane,
- a blood withdrawal line connected to an inlet of the primary chamber,
- a blood return line connected to an outlet of the primary chamber, said blood withdrawal line and blood return line being configured for connection to a patient cardiovascular system,
- a dialysis supply line for circulating a dialysis fluid,
- a dialysis effluent line connected to an outlet of the secondary chamber, and
- a control unit programmed for receiving a value of a first parameter for an isoconductive dialysis, the first parameter being chosen in the group including:
- (i) a concentration of at least one substance;
- (ii) a concentration-related parameter of the substance;
- and (iii) a conductivity or conductivity-related parameter, the method comprising:
- receiving a value of a first parameter for an isoconductive dialysis, the first parameter being chosen in the group including:
- (i) a concentration of at least one substance, (ii) a concentration-related parameter of the substance, and (iii) a conductivity or conductivity-related parameter;
- calculating a second parameter as a function of a main contribution term based on the first parameter and as a function of an offset contribution term, the second parameter being a concentration or a concentration related parameter of a substance in the blood;
- calculating the offset contribution term based on a difference in concentration of at least one further substance in the dialysis fluid and the same further substance in the blood plasma, the further substance chosen from the group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate, and phosphate, wherein the main contribution term contributes to at least 80% of the second parameter and the offset contribution term contributes to less than 20% of the second parameter;
- storing said second parameter value in a memory in communication with the control unit;
- and
- regulating one of (i) a concentration of the substance in the dialysis fluid and (ii) a conductivity of the dialysis fluid, based on the second parameter.
13 more elements
A method of estimating a blood parameter in an apparatus for extracorporeal blood treatment, the apparatus comprising:
- a filtration unit having a primary chamber and a secondary chamber separated by a semi-permeable membrane,
- a blood withdrawal line connected to an inlet of the primary chamber,
- a blood return line connected to an outlet of the primary chamber, said blood lines being configured for connection to a patient cardiovascular system,
- a dialysis supply line for circulating a dialysis fluid,
- a dialysis effluent line connected to an outlet of the secondary chamber, and
- a control unit programmed for receiving a value of a first parameter for an isoconductive dialysis, the isoconductive dialysis being dialysis treatment where the conductivity of the dialysis fluid does not change pre- to post-filtration unit, wherein the first parameter is either:
- (i) an isoconductive substance concentration which is a substance concentration in the dialysis fluid in the isoconductive dialysis, or (ii) the dialysis fluid conductivity in the isoconductive dialysis, the method comprising:
- calculating a sodium concentration in the blood of a patient, as a function of a main contribution term based on the first parameter and as a function of an offset contribution term, wherein the main contribution term is a concentration value which would run an isoconductive dialysis if used as a dialysis fluid concentration of sodium and contributes to at least 80% of the second parameter, and the offset contribution term is dimensionally a concentration of a substance in a fluid and contributes to less than 20% of the second parameter;
- storing said second parameter value in a memory in communication with the control unit, and
- regulating one of (i) a concentration of the substance in the dialysis fluid and (ii) a conductivity of the dialysis fluid, based on the second parameter.
7 more elements
A method of estimating a blood parameter in an apparatus for extracorporeal blood treatment, the apparatus comprising:
- a filtration unit having a primary chamber and a secondary chamber separated by a semi-permeable membrane,
- a blood withdrawal line connected to an inlet of the primary chamber,
- a blood return line connected to an outlet of the primary chamber, said blood lines being configured for connection to a patient cardiovascular system,
- a dialysis supply line for circulating a dialysis fluid,
- a dialysis effluent line connected to an outlet of the secondary chamber, and
- a control unit programmed for receiving a value of a first parameter, wherein the first parameter is an isoconductive sodium concentration or isoconductive sodium concentration-related parameter, the method comprising:
- calculating a concentration or concentration-related parameter of sodium in blood as a function of a main contribution term and of an offset contribution term;
- determining the main contribution term based on the first parameter, wherein the main contribution term is a concentration value which, when used as a dialysis fluid concentration of sodium, performs an isoconductive dialysis;
- calculating the offset contribution term based on:
- (i) a concentration of at least one further substance in the dialysis fluid chosen from a group including bicarbonate, potassium, acetate, lactate, citrate, magnesium, calcium, sulphate, and phosphate, and (ii) a difference between a first molar conductivity of one substance chosen from a group including sodium bicarbonate (NaHCO3), sodium acetate (NACH3COO), trisodium citrate (Na3C6H5O7), sodium lactate (NaC3H5O3), potassium chloride (KCl), and a molar conductivity of sodium chloride (NaCl);
- storing said second parameter value in a memory in communication with the control unit;
- and
- regulating one of (i) a concentration of the substance in the dialysis fluid and (ii) a conductivity of the dialysis fluid, based on the second parameter.
10 more elements
Dependencies are inferred from the claim text.