Dialysis system having non-invasive fluid velocity sensing
First Claim
Patent Images
1. A dialysis system comprising:
- a dialyzer;
a blood pump coupled operably to the dialyzer;
a dialysate inlet pump coupled operably to a dialysate inlet of the dialyzer;
a dialysate outlet pump coupled operably to a dialysate outlet of the dialyzer;
a first non-invasive fluid velocity sensor positioned to sense an inlet velocity of dialysate pumped to the dialyzer inlet by the dialysate inlet pump;
a second non-invasive fluid velocity sensor positioned to sense an outlet velocity of dialysate pumped from the dialyzer outlet by the dialysate outlet pump; and
a logic implementor programmed to;
(i) set a speed of the dialysate inlet pump and a speed of the dialysate outlet pump so that an ultrafiltration rate is achieved, (ii) multiply a cross-sectional area of the dialyzer inlet by the sensed fluid inlet velocity and by a sample time to determine a sample time inlet volume, (iii) multiply a cross-sectional area of the dialyzer outlet by the sensed fluid outlet velocity and by the sample time to determine a sample time outlet volume, (iv) integrate the determined sample time inlet and outlet volumes over a treatment period to determine a total amount of dialysate delivered to and from the dialyzer during the treatment, and (v) use the determined total amount of dialysate delivered to and from the dialyzer to adjust the ultrafiltration rate as treatment proceeds.
2 Assignments
0 Petitions
Accused Products
Abstract
A dialysis system includes a dialyzer; a blood pump coupled operably to a dialyzer; a dialysate inlet pump couple operably to a dialysate inlet of the dialyzer; a dialysate outlet pump coupled operably to a dialysate outlet of the dialyzer; a first non-invasive fluid velocity sensor positioned to sensor of inlet flowrate of dialysate pumped to the dialysate inlet by the dialysate inlet pump; and a second non-invasive fluid velocity sensor positioned to sense an outlet flowrate of dialysate pumped from the dialysate outlet by the dialysate outlet pump.
187 Citations
27 Claims
-
1. A dialysis system comprising:
-
a dialyzer; a blood pump coupled operably to the dialyzer; a dialysate inlet pump coupled operably to a dialysate inlet of the dialyzer; a dialysate outlet pump coupled operably to a dialysate outlet of the dialyzer; a first non-invasive fluid velocity sensor positioned to sense an inlet velocity of dialysate pumped to the dialyzer inlet by the dialysate inlet pump; a second non-invasive fluid velocity sensor positioned to sense an outlet velocity of dialysate pumped from the dialyzer outlet by the dialysate outlet pump; and a logic implementor programmed to;
(i) set a speed of the dialysate inlet pump and a speed of the dialysate outlet pump so that an ultrafiltration rate is achieved, (ii) multiply a cross-sectional area of the dialyzer inlet by the sensed fluid inlet velocity and by a sample time to determine a sample time inlet volume, (iii) multiply a cross-sectional area of the dialyzer outlet by the sensed fluid outlet velocity and by the sample time to determine a sample time outlet volume, (iv) integrate the determined sample time inlet and outlet volumes over a treatment period to determine a total amount of dialysate delivered to and from the dialyzer during the treatment, and (v) use the determined total amount of dialysate delivered to and from the dialyzer to adjust the ultrafiltration rate as treatment proceeds. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
-
10. A dialysis system comprising:
-
a dialysate inlet pump configured to pump dialysate to a dialyzer; a dialysate outlet pump configured to pump dialysate from the dialyzer; a dialysis instrument configured to actuate the dialysate inlet and outlet pumps, the instrument including a first non-invasive fluid velocity sensor and a second non-invasive fluid velocity sensor; a disposable dialysate carrying unit operable with the dialysis instrument, the disposable unit including a to-dialyzer channel pathway, at least a portion of which having a known cross-sectional area defined by walls extending from a rigid base plate of the disposable unit, the to-dialyzer portion when placed in the dialysis instrument positioned to operate with the first non-invasive fluid velocity sensor, the disposable unit further including a from-dialyzer channel pathway, at least a portion of which having a known cross-sectional area defined by walls extending from a rigid base plate of the disposable unit, the from-dialyzer portion when placed in the dialysis instrument positioned to operate with the second non-invasive fluid velocity sensor; and a logic implementor programmed to (i) integrate a signal from the first non-invasive fluid velocity sensor to determine an amount of dialysate delivered to the dialyzer during a treatment, (ii) integrate a signal from the second non-invasive fluid velocity sensor to determine an amount of dialysate delivered from the dialyzer during the treatment, and (iii) use the determined amount of dialysate delivered to and from the dialyzer to determine an ultrafiltration rate as the treatment proceeds. - View Dependent Claims (11, 12, 13, 14, 15, 16, 17)
-
-
18. A dialysis system comprising:
-
a dialysate inlet pump configured to pump dialysate to a dialyzer; a dialysate outlet pump configured to pump dialysate from the dialyzer; a dialysis instrument configured to actuate the dialysate inlet and outlet pumps, the instrument including a first non-invasive fluid velocity sensor and a second non-invasive fluid velocity sensor; a disposable dialysate carrying unit operable with the dialysis instrument, the disposable unit including a to-dialyzer pathway, at least a portion of the to-dialyzer pathway having a sensor area operable with the first non-invasive fluid velocity sensor when the unit is placed in the dialysis instrument, the to-dialyzer sensing area having an entrance length long enough to allow dialysate flow to be at least substantially laminar prior to reaching the first non-invasive fluid velocity sensor, the disposable unit further including a from-dialyzer pathway, at least a portion of the from-dialyzer pathway having a sensor area operable with the second non-invasive fluid velocity sensor when the unit is placed in the dialysis instrument, the from-dialyzer sensing area having an entrance length long enough to allow dialysate flow to be at least substantially laminar prior to reaching the second non-invasive fluid velocity sensor; and a logic implementor programmed to (i) integrate a signal from the first non-invasive fluid velocity sensor to determine an amount of dialysate delivered to the dialyzer during a treatment, (ii) integrate a signal from the second non-invasive fluid velocity sensor to determine an amount of dialysate delivered from the dialyzer during the treatment, and (iii) use the determined total amount of dialysate delivered to and from the dialyzer to determine an ultrafiltration rate as the treatment proceeds. - View Dependent Claims (19, 20)
-
-
21. A dialysis system comprising:
-
a dialyzer; a blood pump coupled operably to the dialyzer; a dialysate inlet pump coupled operably to a dialysate inlet of the dialyzer; a dialysate outlet pump coupled operably to a dialysate outlet of the dialyzer; a first non-invasive fluid velocity sensor positioned to sense an inlet velocity of dialysate pumped to the dialyzer inlet by the dialysate inlet pump; a second non-invasive fluid velocity sensor positioned to sense an outlet velocity of dialysate pumped from the dialyzer outlet by the dialysate outlet pump; and a logic implementor programmed to;
(i) subtract a sensed inlet velocity signal from a sensed outlet velocity signal to determine an instantaneous ultrafiltration velocity, (ii) multiply the determined instantaneous ultrafiltration velocity by a cross-sectional area of the dialyzer inlet to determine an instantaneous ultrafiltration rate, (iii) multiply the determined instantaneous ultrafiltration rate by a sample volume to determine an instantaneous ultrafiltration volume, and (iv) integrate the determined instantaneous volume to determine a total amount of ultrafiltration.
-
-
22. A dialysis system comprising:
-
a dialysis instrument including a blood pump, a dialysate inlet pump, a dialysate outlet pump, and a fluid velocity sensor including an emitter and a receiver; a dialyzer arranged (i) to receive blood pumped by the blood pump, (ii) to receive fresh dialysate pumped by the dialysate inlet pump and (iii) such that used dialysate is pumped from the dialyzer by the dialysate outlet pump; a disposable cassette including a to-dialyzer dialysate pathway carrying dialysate pumped by the dialysate inlet pump and a from-dialyzer dialysate pathway carrying used dialysate pumped by the dialysate outlet pump, one of the to-dialyzer dialysate pathway and the from-dialyzer dialysate pathway including a sensing area so positioned and arranged such that when the disposable cassette is mounted to the instrument, the sensing area is coupled operably to both the emitter and the receiver of the fluid velocity sensor; and a logic implementor programmed to;
(i) receive a sensed velocity signal from the fluid velocity sensor, (ii) multiply the sensed velocity by a cross-sectional area of the sensing area to determine an instantaneous ultrafiltration rate, (iii) multiply the determined instantaneous ultrafiltration rate by a sample volume to determine an instantaneous ultrafiltration volume, and (iv) integrate the determined instantaneous volume to determine a total amount of ultrafiltration. - View Dependent Claims (23, 24, 25, 26, 27)
-
Specification