US 2026/0199571 A1Published application

Determining internal filtration rate within a capillary hemodialyzer

AssigneeGambro Lundia AB

InventorsDanilo DONATO, Markus STORR

Life of this patent

Estimating the term…

Abstract

The present disclosure relates to a method and a device for determining an internal filtration rate IFR within a capillary hemodialyzer.

Claims20

Dependent claims

A method of performing expanded hemodialysis (HDx) on a patient, the method comprising a step of using a capillary hemodialyzer on the patient,

wherein the capillary hemodialyzer comprises a housing,
wherein the capillary hemodialyzer comprises hollow fiber membranes,
wherein the capillary hemodialyzer is configured to comprise an internal filtration rate (IFR),
wherein the capillary hemodialyzer comprises properties including dimensions, a flow rate of blood through the capillary hemodialyzer, and a flow rate of dialysate through the capillary hemodialyzer,
wherein the hollow fiber membranes comprise properties including dimensions and physical parameters, and
wherein the method of performing HDx on the patient comprises a step of measuring the IFR of the capillary hemodialyzer, wherein the IFR is calculated according to steps comprising:
i) acquiring data on the properties of the capillary hemodialyzer and the properties of hollow fiber membranes present in the capillary hemodialyzer, the data comprising a diameter dH of the housing of the capillary hemodialyzer, a number N of the hollow fiber membranes present in the capillary hemodialyzer, an effective length L of the hollow fiber membranes present in the capillary hemodialyzer, a total surface area Atot of the hollow fiber membranes present in the capillary hemodialyzer, an internal diameter dB of the hollow fiber membranes present in the capillary hemodialyzer, a wall thickness δM of the hollow fiber membranes present in the capillary hemodialyzer, a porosity εM of the hollow fiber membranes present in the capillary hemodialyzer, and an ultrafiltration coefficient KUF of the hollow fiber membranes present in the capillary hemodialyzer;
ii) acquiring a blood flow rate QB and a dialysis flow rate QD through the capillary hemodialyzer during operation of the capillary hemodialyzer;
iii) determining the IFR of the capillary hemodialyzer, based on the data acquired in steps i and ii, wherein the IFR is determined according to
IFR
=
N
⁢
π
⁢
d
B
⁢
K
⁢
{
(
P
B
,
out
-
P
D
,
out
-
π
0
)
⁢
x
i
-
1
⁢
2
⁢
8
⁢
μ
B
N
⁢
π
⁢
d
B
4
[
Q
B
(
x
i
2
2
-
L
⁢
x
i
)
-
N
⁢
π
⁢
d
B
[
v
2
-
v
1
6
⁢
L
⁢
(
x
i
4
4
-
L
3
⁢
x
i
)
+
v
1
2
⁢
(
x
i
3
3
-
L
2
⁢
x
i
)
]
]
+
μ
D
2
⁢
N
⁢
π
⁢
f
R
O
⁢
R
K
[
Q
D
⁢
x
i
2
2
-
Nπ
⁢
d
B
[
v
2
-
v
1
2
⁢
L
⁢
(
x
i
4
1
⁢
2
-
L
2
2
⁢
x
i
2
)
+
v
1
(
x
i
3
6
-
L
2
⁢
x
i
2
)
]
]
}
wherein
N refers to the number of hollow fiber membranes present in the capillary hemodialyzer;
dB refers to the internal diameter of hollow fiber membranes present in the capillary hemodialyzer;
K refers to
K
UF
A
tot
⁢
E
M
in which KUF refers to the ultrafiltration coefficient of the hollow fiber membranes present in the capillary hemodialyzer,
Atot refers to the total membrane area of the hollow fiber membranes present in the capillary hemodialyzer
(
A
tot
=
N
⁢
Π
⁢
d
B
⁢
L
)
,
εM refers to the membrane porosity of the hollow fiber membranes present in the capillary hemodialyzer;
μB, out refers to the blood pressure at capillary hemodialyzer exit;
μD, out refers to the dialysate pressure at capillary hemodialyzer exit;
Πo refers to the average oncotic pressure;
xi refers to the location of inversion point (Jν(xi)=0);
μB refers to the blood viscosity;
QB refers to the blood flow rate;
L refers to the effective length of hollow fiber membranes present in the capillary hemodialyzer;
ν1 refers to J(0);
ν2 refers to Jv(L);
μD refers to the dialysate viscosity;
QD refers to the dialysate flow rate;
and
f
R
O
,
R
K
=
R
K
4
-
R
O
4
1
⁢
6
+
R
K
2
2
⁢
(
R
K
2
2
⁢
ln
⁡
(
R
O
R
K
)
+
R
K
2
-
R
O
2
4
)
-
R
O
2
8
⁢
(
R
K
2
-
R
O
2
)
,
R
O
=
d
B
2
+
δ
M
R
K
=
R
O
+
δ
ε
wherein dB refers to the internal diameter of the hollow fiber membranes present in the h capillary hemodialyzer, δM refers to the wall thickness of the hollow fiber membranes present in the capillary hemodialyzer, δc refers to the thickness of the diffusion layer around the hollow fiber membranes present in the capillary hemodialyzer.

307 more elements

A method of performing expanded hemodialysis (HDx) on a patient, the method comprising a step of using a capillary hemodialyzer on the patient,

wherein the capillary hemodialyzer comprises a housing,
wherein the capillary hemodialyzer comprises hollow fiber membranes,
wherein the capillary hemodialyzer is configured to comprise an internal filtration rate (IFR),
wherein the capillary hemodialyzer comprises properties including dimensions, a flow rate of blood through the capillary hemodialyzer, and a flow rate of dialysate through the capillary hemodialyzer,
wherein the hollow fiber membranes comprise properties including dimensions and physical parameters, and
wherein the method of performing HDx on the patient comprises a step of increasing the IFR of the capillary hemodialyzer, wherein the IFR is calculated according to steps comprising:
i) acquiring data on the properties of the capillary hemodialyzer and the properties of hollow fiber membranes present in the capillary hemodialyzer, the data comprising a diameter dH of the housing of the capillary hemodialyzer, a number N of the hollow fiber membranes present in the capillary hemodialyzer, an effective length L of the hollow fiber membranes present in the capillary hemodialyzer, a total surface area Atot of the hollow fiber membranes present in the capillary hemodialyzer, an internal diameter dB of the hollow fiber membranes present in the capillary hemodialyzer, a wall thickness δM of the hollow fiber membranes present in the capillary hemodialyzer, a porosity εM of the hollow fiber membranes present in the capillary hemodialyzer, and an ultrafiltration coefficient KUF of the hollow fiber membranes present in the capillary hemodialyzer;
ii) acquiring a blood flow rate QB and a dialysis flow rate QD through the capillary hemodialyzer during operation of the capillary hemodialyzer;
iii) determining the IFR of the capillary hemodialyzer, based on the data acquired in steps i and ii, wherein the IFR is determined according to
IFR
=
N
⁢
π
⁢
d
B
⁢
K
⁢
{
(
P
B
,
out
-
P
D
,
out
-
π
0
)
⁢
x
i
-
1
⁢
2
⁢
8
⁢
μ
B
N
⁢
π
⁢
d
B
4
[
Q
B
(
x
i
2
2
-
L
⁢
x
i
)
-
N
⁢
π
⁢
d
B
[
v
2
-
v
1
6
⁢
L
⁢
(
x
i
4
4
-
L
3
⁢
x
i
)
+
v
1
2
⁢
(
x
i
3
3
-
L
2
⁢
x
i
)
]
]
+
μ
D
2
⁢
N
⁢
π
⁢
f
R
O
,
R
K
[
Q
D
⁢
x
i
2
2
-
N
⁢
π
⁢
d
B
[
v
2
-
v
1
2
⁢
L
⁢
(
x
i
4
1
⁢
2
-
L
2
2
⁢
x
i
2
)
+
v
1
(
x
i
3
6
-
L
2
⁢
x
i
2
)
]
]
}
wherein
N refers to the number of hollow fiber membranes present in the capillary hemodialyzer;
dB refers to the internal diameter of hollow fiber membranes present in the capillary hemodialyzer;
K refers to
K
UF
A
tot
⁢
E
M
in which KUF refers to the ultrafiltration coefficient of the hollow fiber membranes present in the capillary hemodialyzer,
Atot refers to the total membrane area of the hollow fiber membranes present in the capillary hemodialyzer
(
A
tot
=
N
⁢
Π
⁢
d
B
⁢
L
)
,
εM refers to the membrane porosity of the hollow fiber membranes present in the capillary hemodialyzer;
PB, out refers to the blood pressure at capillary hemodialyzer exit;
PD, out refers to the dialysate pressure at capillary hemodialyzer exit;
Πo refers to the average oncotic pressure;
xi refers to the location of inversion point (Jν(xi)=0);
μB refers to the blood viscosity;
QB refers to the blood flow rate;
L refers to the effective length of hollow fiber membranes present in the capillary hemodialyzer;
ν1 refers to J(0);
ν2 refers to Jv(L);
μD refers to the dialysate viscosity;
QD refers to the dialysate flow rate;
and
f
R
O
,
R
K
=
R
K
4
-
R
O
4
1
⁢
6
+
R
K
2
2
⁢
(
R
K
2
2
⁢
ln
⁡
(
R
O
R
K
)
+
R
K
2
-
R
O
2
4
)
-
R
O
2
8
⁢
(
R
K
2
-
R
O
2
)
,
R
O
=
d
B
2
+
δ
M
R
K
=
R
O
+
δ
ε
wherein dB refers to the internal diameter of the hollow fiber membranes present in the h capillary hemodialyzer, δM refers to the wall thickness of the hollow fiber membranes present in the capillary hemodialyzer, δc refers to the thickness of the diffusion layer around the hollow fiber membranes present in the capillary hemodialyzer.

309 more elements

Dependencies are inferred from the claim text.

Facts

Application: 19/560,778Filed 9 Mar 2026
Priority: EP 19202905.614 Oct 2019
Published: 16 Jul 2026
Term ends: Not estimatedThe source records don’t support an estimate.

Classification8 codes

A61M 1/1605
Regulation parameters: physical characteristics of the dialysate fluid
A61M 1/1613
Control or regulation: profiling or modelling of patient or predicted treatment evolution or outcome
A61M 1/1627
Disposition or location of membranes relative to fluids: dialyser of the inside perfusion type, i.e. blood flow inside hollow membrane fibres or tubes
A61M 1/1647
Constructional aspects thereof: with flow rate measurement of the dialysis fluid, upstream and downstream of the dialyser

Family

Application17/768,516Continuation · filed 13 Oct 2020
Application19/560,778Continuation
US 2024/0181142 A1Published application
US 2026/0199571 A1This patent

From the US filing history. Foreign family members aren’t listed.

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A method of performing expanded hemodialysis (HDx) on a patient, the method comprising a step of using a capillary hemodialyzer on the patient,

wherein the capillary hemodialyzer comprises a housing,
wherein the capillary hemodialyzer comprises hollow fiber membranes,
wherein the capillary hemodialyzer is configured to comprise an internal filtration rate (IFR),
wherein the capillary hemodialyzer comprises properties including dimensions, a flow rate of blood through the capillary hemodialyzer, and a flow rate of dialysate through the capillary hemodialyzer,
wherein the hollow fiber membranes comprise properties including dimensions and physical parameters, and
wherein the method of performing HDx on the patient comprises a step of measuring the IFR of the capillary hemodialyzer, wherein the IFR is calculated according to steps comprising:
i) acquiring data on the properties of the capillary hemodialyzer and the properties of hollow fiber membranes present in the capillary hemodialyzer, the data comprising a diameter dH of the housing of the capillary hemodialyzer, a number N of the hollow fiber membranes present in the capillary hemodialyzer, an effective length L of the hollow fiber membranes present in the capillary hemodialyzer, a total surface area Atot of the hollow fiber membranes present in the capillary hemodialyzer, an internal diameter dB of the hollow fiber membranes present in the capillary hemodialyzer, a wall thickness δM of the hollow fiber membranes present in the capillary hemodialyzer, a porosity εM of the hollow fiber membranes present in the capillary hemodialyzer, and an ultrafiltration coefficient KUF of the hollow fiber membranes present in the capillary hemodialyzer;
ii) acquiring a blood flow rate QB and a dialysis flow rate QD through the capillary hemodialyzer during operation of the capillary hemodialyzer;
iii) determining the IFR of the capillary hemodialyzer, based on the data acquired in steps i and ii, wherein the IFR is determined according to
IFR
=
N
⁢
π
⁢
d
B
⁢
K
⁢
{
(
P
B
,
out
-
P
D
,
out
-
π
0
)
⁢
x
i
-
1
⁢
2
⁢
8
⁢
μ
B
N
⁢
π
⁢
d
B
4
[
Q
B
(
x
i
2
2
-
L
⁢
x
i
)
-
N
⁢
π
⁢
d
B
[
v
2
-
v
1
6
⁢
L
⁢
(
x
i
4
4
-
L
3
⁢
x
i
)
+
v
1
2
⁢
(
x
i
3
3
-
L
2
⁢
x
i
)
]
]
+
μ
D
2
⁢
N
⁢
π
⁢
f
R
O
⁢
R
K
[
Q
D
⁢
x
i
2
2
-
Nπ
⁢
d
B
[
v
2
-
v
1
2
⁢
L
⁢
(
x
i
4
1
⁢
2
-
L
2
2
⁢
x
i
2
)
+
v
1
(
x
i
3
6
-
L
2
⁢
x
i
2
)
]
]
}
wherein
N refers to the number of hollow fiber membranes present in the capillary hemodialyzer;
dB refers to the internal diameter of hollow fiber membranes present in the capillary hemodialyzer;
K refers to
K
UF
A
tot
⁢
E
M
in which KUF refers to the ultrafiltration coefficient of the hollow fiber membranes present in the capillary hemodialyzer,
Atot refers to the total membrane area of the hollow fiber membranes present in the capillary hemodialyzer
(
A
tot
=
N
⁢
Π
⁢
d
B
⁢
L
)
,
εM refers to the membrane porosity of the hollow fiber membranes present in the capillary hemodialyzer;
μB, out refers to the blood pressure at capillary hemodialyzer exit;
μD, out refers to the dialysate pressure at capillary hemodialyzer exit;
Πo refers to the average oncotic pressure;
xi refers to the location of inversion point (Jν(xi)=0);
μB refers to the blood viscosity;
QB refers to the blood flow rate;
L refers to the effective length of hollow fiber membranes present in the capillary hemodialyzer;
ν1 refers to J(0);
ν2 refers to Jv(L);
μD refers to the dialysate viscosity;
QD refers to the dialysate flow rate;
and
f
R
O
,
R
K
=
R
K
4
-
R
O
4
1
⁢
6
+
R
K
2
2
⁢
(
R
K
2
2
⁢
ln
⁡
(
R
O
R
K
)
+
R
K
2
-
R
O
2
4
)
-
R
O
2
8
⁢
(
R
K
2
-
R
O
2
)
,
R
O
=
d
B
2
+
δ
M
R
K
=
R
O
+
δ
ε
wherein dB refers to the internal diameter of the hollow fiber membranes present in the h capillary hemodialyzer, δM refers to the wall thickness of the hollow fiber membranes present in the capillary hemodialyzer, δc refers to the thickness of the diffusion layer around the hollow fiber membranes present in the capillary hemodialyzer.

307 more elements

Facts

Application

19/560,778Filed 9 Mar 2026

Priority

EP 19202905.614 Oct 2019

Published

16 Jul 2026

Term ends

Not estimatedThe source records don’t support an estimate.

Classification8 codes

A61M 1/1605
Regulation parameters: physical characteristics of the dialysate fluid
A61M 1/1613
Control or regulation: profiling or modelling of patient or predicted treatment evolution or outcome
A61M 1/1627
Disposition or location of membranes relative to fluids: dialyser of the inside perfusion type, i.e. blood flow inside hollow membrane fibres or tubes
A61M 1/1647
Constructional aspects thereof: with flow rate measurement of the dialysis fluid, upstream and downstream of the dialyser