Patient line check and occlusion detection for a dialysis machine using adjusted pump operating parameters

Patent metadata

Field	Value
Publication number	US-11654220-B2
Application number	US-201916447759-A
Country	US
Kind code	B2
Filing date	Jun 20, 2019
Priority date	Jun 20, 2019
Publication date	May 23, 2023
Grant date	May 23, 2023

Abstract

A dialysis machine (e.g., a peritoneal dialysis (PD) machine) can include a patient line that provides dialysate solution to a patient and removes effluent dialysate from the patient through a catheter. During a drain phase of a PD treatment, an occlusion can occur at different locations in the patient line and/or catheter. A pressure sensor can detect a change in pressure of the fluid at the proximal end of the patient line to infer a potential occlusion in the patient line. Prior to setting an alarm to alert the patient of the blockage in the patient line, operating parameters of the PD machine can be changed to attempt to correct the issue. In an embodiment, the pump mechanism can be cycled at a reduced speed or a reduced rate in order to confirm the occlusion or attempt to alleviate the low fluid flow condition before the alarm is set.

First claim

What is claimed is:

1. A peritoneal dialysis (PD) system, comprising:
at least one pump configured to provide or withdraw fluid from a line connected to a catheter inserted into a peritoneal cavity of a patient;
a cassette including at least one pump chamber and at least one pressure sensing chamber fluidly coupled to the at least one pump chamber, wherein the line is fluidly coupled to the at least one pump chamber; and
a processor configured to:
detect a low fluid flow condition during a phase of a PD cycle,
responsive to the low fluid flow condition, adjust operating parameters of the at least one pump to reduce a speed of the at least one pump from a first speed to a second speed that is less than the first speed; and
detect a low fluid volume condition while the at least one pump is operated at the second speed, wherein detecting the low fluid volume condition comprises detecting that a volume of fluid that enters the at least one pump chamber during a retraction stroke of any piston included in the at least one pump during each of a consecutive number of strokes at the second speed is less than a threshold volume of fluid, and wherein the consecutive number of strokes is at least two consecutive retraction strokes.

2. The PD system of claim 1 , wherein the processor is configured to, after detecting the low fluid volume condition, perform one or more of:
trigger an alarm; or
terminate the phase of the PD cycle.

3. The PD system of claim 1 , wherein detecting the low fluid flow condition comprises detecting that a fluid flow rate over a period of time is less than a threshold value.

4. The PD system of claim 3 , wherein the threshold value is less than or equal to 30 milliliters per minute and the period of time is at least 5 minutes.

5. The PD system of claim 1 , wherein the low fluid flow condition comprises determining that a total volume of fluid drained from the peritoneal cavity during a drain phase of the PD cycle is less than a threshold value after a period of time has elapsed, the period of time measured from the start of the drain phase of the PD cycle.

6. The PD system of claim 5 , wherein the threshold value is equal to 35 percent of an expected drain volume and the period of time is 50 percent of an expected drain time.

7. The PD system of claim 5 , wherein the threshold value is equal to 70 percent of an expected drain volume and the period of time is an expected drain time.

8. The PD system of claim 1 , wherein the consecutive number of strokes is equal to or greater than four consecutive retraction strokes of any piston included in the at least one pump and the threshold volume is less than or equal to 1.5 milliliters.

9. The PD system of claim 1 , wherein the processor is further configured to determine that a drain exit criteria is met.

10. The PD system of claim 1 , wherein the at least one pump comprises:
a first piston configured to move towards the cassette to decrease a volume of a first pump chamber of the at least one pump chamber and move away from the cassette to increase the volume of the first pump chamber of the at least one pump chamber; and
a second piston configured to move towards the cassette to decrease a volume of a second pump chamber of the at least one pump chamber and move away from the cassette to increase the volume of the second pump chamber of the at least one pump chamber,
wherein a first side of the cassette is disposed proximate a cassette interface of a PD machine and a second side of the cassette is disposed proximate a door that applies a force to at least one region of the second side of the cassette to hold the cassette against the cassette interface.

11. The PD system of claim 10 , the system further comprising:
a number of inflatable members configured to open a fluid path between the line and the at least one pump chamber.

12. A method of operating a peritoneal dialysis (PD) machine, the method comprising:
operating one or more pumps during a drain phase of a PD cycle to drain effluent dialysate from a peritoneal cavity of a patient fluidly coupled to the PD machine, wherein a distal end of a patient line is attached to a catheter inserted into the peritoneal cavity of the patient and a proximal end of the patient line is attached to a port of a cassette inserted into the PD machine, wherein the cassette includes at least one pump chamber and at least one sensing chamber fluidly coupled to the at least one pump chamber, and wherein the patient line is fluidly connected to the at least one pump chamber;
detecting a low fluid flow condition during the drain phase;
adjusting, responsive to the low fluid flow condition, operating parameters of the one or more pumps to reduce a speed of the at least one pump from a first speed to a second speed that is less than the first speed; and
detecting, after adjusting the operating parameters to reduce the speed of the at least one pump from the first speed to the second speed, a low fluid volume condition, wherein detecting the low fluid volume condition comprises detecting that a volume of fluid that enters the at least one pump chamber during a retraction stroke of any piston included in the one or more pumps during each of a consecutive number of strokes at the adjusted operating parameters is less than a threshold volume of fluid, and wherein the consecutive number of strokes is at least two consecutive retraction strokes.

13. The method of claim 12 , further comprising, after detecting the low fluid volume condition, performing one or more of:
triggering an alarm; or
terminating the drain phase of the PD cycle.

14. The method of claim 12 , wherein the low fluid flow condition comprises detecting that a fluid flow rate over a period of time is less than a threshold value.

15. The method of claim 12 , wherein the low fluid flow condition comprises determining that a total volume of fluid drained from the peritoneal cavity during the drain phase of the PD cycle is less than a threshold value after a period of time has elapsed, the period of time measured from the start of the drain phase of the PD cycle.

16. The method of claim 12 , wherein the consecutive number of strokes is equal to or greater than four retraction strokes of the one or more pumps.

17. The method of claim 12 , further comprising, prior to terminating the drain phase of the PD cycle, determining that a drain exit criteria is met.

Assignees

• Fresenius Medical Care Holdings Inc

Inventors

• Plahey Kulwinder S
• Zhu Jie

Classifications

• A61M2205/3396

  Reservoirs being alternately filled and emptied for measuring flow rate or delivered volume · CPC title

• A61M2205/128

  with incorporated valves · CPC title

• A61M2205/106

  reciprocating · CPC title

• A61M1/28

  Peritoneal dialysis {; Other peritoneal treatment, e.g. oxygenation} · CPC title

• A61M2205/18

  with alarm · CPC title