Degassing system for dialysis

Patent metadata

Field	Value
Publication number	US-2016166751-A1
Application number	US-201414566686-A
Country	US
Kind code	A1
Filing date	Dec 10, 2014
Priority date	Dec 10, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

The degassing system can include a degassing vessel and can utilize a vacuum pump and a fluid pump located downstream of the degassing vessel to control the pressure within the degassing vessel in order to control the concentration of gases in fluid exiting the degassing system. The degassing system can further comprise sensors in communication with the pumps to control the rate of flow and pressure through the degassing system. The degassing system may be placed in a dialysate flow path to remove dissolved gases including carbon dioxide from the dialysate.

First claim

We claim:

1 . A degassing vessel; comprising:
a fluid inlet in the degassing vessel fluidly connected to a flow restriction; a fluid outlet in the degassing vessel for fluid connection to a fluid pump downstream of the degassing vessel; and a gas outlet for fluid connection to a vacuum pump.

2 . The degassing vessel of claim 1 , further comprising a carbon dioxide sensor positioned to detect carbon dioxide at the outlet of the degassing vessel.

3 . The degassing vessel of claim 1 , further comprising one or more selected from the group consisting of a degas sprayer, a nucleation chamber, and combinations thereof;
wherein fluid entering the degassing vessel through the fluid inlet passes through any one of the degas sprayer, the nucleation chamber, or the combinations thereof.

4 . The degassing vessel of claim 1 , wherein the flow restriction is selected from the group consisting of orifices, venturis, spray nozzles, a narrowing, pinch valves, gate valves, variable orifice valves, a pressure regulator, and combinations thereof.

5 . The degassing vessel of claim 1 , further comprising a pressure sensor configured to determine a fluid pressure in the degassing vessel.

6 . The degassing vessel of claim 1 , further comprising one or more sensors in the degassing vessel wherein the one or more sensors are configured to determine the fluid level in the degassing vessel.

7 . The degassing vessel of claim 6 , wherein the one or more sensors comprise an upper level sensor and a lower level sensor in the degassing vessel; wherein the upper level sensor detects whether the fluid level in the degassing vessel is above a first pre-set point; and
wherein the lower level sensor detects whether the fluid level in the degassing vessel is below a second pre-set point.

8 . The degassing vessel of claim 1 , further comprising:
an overflow float in the degassing vessel, the overflow float being of a lower density than water; and a mechanical vent valve placed on the degassing vessel at the gas outlet such that if the fluid level in the degassing vessel is above a pre-set point, the overflow float will cover the mechanical vent valve and block fluid from passing through the mechanical vent valve.

9 . A degassing system for use in dialysis, comprising:
a degassing vessel having a fluid inlet, and a fluid outlet; a degas flow restrictor fluidly connected to the inlet of the degassing vessel; a fluid pump fluidly connected to the degassing vessel and located downstream of the degassing vessel, for pulling fluid into the degassing vessel through the fluid inlet and out of the degassing vessel through the fluid outlet; and a vacuum pump attached to the degassing vessel for removing gas from the degassing vessel.

10 . The degassing system of claim 9 , further comprising one or more selected from the group consisting of a degas sprayer located inside the degassing vessel at the fluid inlet of the degassing vessel such that fluid entering the degassing vessel through the fluid inlet passes through the degas sprayer; a nucleation chamber located either between the degas flow restrictor and the degassing vessel or inside the degassing vessel; and combinations thereof.

11 . The degassing system of claim 10 , wherein the selected nucleation chamber comprises one or more of glass beads, fiber mesh and a filter.

12 . The degassing system of claim 9 , further comprising a carbon dioxide sensor located downstream of the degassing vessel.

13 . The degassing system of claim 9 further comprising a pressure sensor located between the degas flow restrictor and the fluid pump.

14 . The degassing system of claim 9 , wherein the degassing restrictor further comprises a pressure regulator.

15 . The degassing system of claim 12 , further comprising a control unit in electronic communication with the carbon dioxide sensor, the vacuum pump and the fluid pump.

16 . The degassing system of claim 15 , wherein the control unit can automatically adjust the pump rates of the fluid pump or the vacuum pump in response to the information received from the carbon dioxide sensor.

17 . The degassing system of claim 13 , further comprising a control unit in electronic communication with the pressure sensor and at least one of the fluid pump, vacuum pump or flow restrictor.

18 . The degassing system of claim 17 , wherein the control unit can automatically adjust the pump rates of the fluid pump or the vacuum pump in response to the information received from the pressure sensor.

19 . The degassing system of claim 17 , wherein the control unit can automatically adjust the amount of flow restriction caused by the flow restrictor.

20 . The degassing system of claim 9 , further comprising a vent valve positioned on a connector, wherein the connector is attached to the degassing vessel, and wherein gas can flow into or out of the degassing vessel through the vent valve.

21 . The degassing system of claim 9 , wherein the degasser is positioned in a degassing flow loop and wherein the degassing flow loop is fluidly connected to a dialysate flow loop and is parallel to the dialysate flow loop; and wherein the flow rate of the fluid in the degassing flow loop can be operated independently of the flow rate of the fluid in the dialysate flow loop.

22 . The degassing system of claim 20 , wherein air can be drawn into the degassing vessel through the vent valve and out through a fluid port of the degassing vessel.

23 . The degassing system of claim 9 , wherein the fluid pump and vacuum pump are any one of a gear pump, a peristaltic pump, a diaphragm pump or an impeller pump, or combinations thereof.

24 . The degassing system of claim 9 , further comprising one or more sensors in the degassing vessel; wherein the one or more sensors detect the fluid level in the degassing vessel;
wherein if the one or more sensors detect that the fluid level in the degassing vessel is above a first pre-set point, either the pump rate of the fluid pump is increased, the pump rate of the vacuum pump is decreased, or a combination thereof; and wherein if the one or more sensors detect that the fluid level in the degassing vessel is below a second pre-set point, either the pump rate of the fluid pump is decreased, the pump rate of the vacuum pump is increased, or a combination thereof.

25 . The degassing system of claim 9 ,wherein the fluid pump and vacuum pump are capable of creating an absolute pressure in the degassing vessel of between any of 60 mmHg and 200 mmHg, 60 mmHg and 100 mmHg, 80 mmHg and 150 mmHg, and 100 mmHg and 200 mmHg.

26 . The degassing system of claim 16 , wherein in response to a signal from the carbon dioxide sensor showing that the carbon dioxide concentration is above a pre-set point, the control unit is configured to automatically do one or more of:
a. increase the pump rate of the fluid pump; b. increase the pump rate of the vacuum pump; or c. combinations thereof.

27 . The degassing system of claim 16 wherein in response to a signal from the carbon dioxide sensor showing that the carbon dioxide concentration is below a pre-set point, the control unit is configured to automatically do one or more of:
a. shut off the fluid pump;
b. shut off the vacuum pump;
c. decrease the pump rate of the fluid pump;
d. decrease the pump rate of the vacuum pump; or
e. combinations there

Assignees

• Medtronic Inc

Inventors

• Meyer Thomas E
• Hajko William P
• Bloomberg Daniel Jordan

Classifications

• B01D19/0047

  Atomizing, spraying, trickling · CPC title

• A61M2202/0225

  Carbon oxides, e.g. Carbon dioxide · CPC title

• A61M2205/3386

  Low level detectors · CPC title

• A61M2205/3382

  Upper level detectors · CPC title

• A61M1/1696

  with dialysate regeneration · CPC title