Infusion device for medical fluids

• US 20050234382A1
• Filed: 04/13/2005
• Published: 10/20/2005
• Est. Priority Date: 04/20/2004
• Status: Active Grant

• Current Assignee: Gambro Lundia AB (Baxter International Inc.)
• Original Assignee: Gambro Lundia AB (Baxter International Inc.)
• Inventors: Tonelli, Claudio, Cestari, Silvano, Ligabue, Andrea
• Granted Patent: US 7,517,332 B2
• Time in Patent Office: Days
• US Class Current: 604/4.10
• CPC Class Codes: A61M 1/3672 Means preventing coagulation
• CPC Class Codes: A61M 2202/0478 Heparin
• CPC Class Codes: A61M 2205/18 with alarm
• CPC Class Codes: A61M 2205/332 Force measuring means
• CPC Class Codes: A61M 2205/50 with microprocessors or computers
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 5/1456 with a replaceable reservoir comprising a piston rod to be moved into the reservoir, e.g. the piston rod is part of the removable reservoir
• CPC Class Codes: A61M 5/16854 by monitoring line pressure

Abstract

An infusion device comprises a pusher for a plunger of a syringe containing a liquid to be infused. A load cell measures the push force. An encoder associated to a motor commanding the pusher measures the displacement of the pusher. A controller signals an alarm when the ratio between the variation of the push force and the displacement exceeds a predetermined threshold. The device, which serves for infusing an anticoagulant into an extracorporeal blood circuit in a dialysis apparatus, is able to signal an onset of an anomalous situation of lack of infusion in good time.

Claims

1. A device for infusion of a liquid, comprising:

an actuator for exerting an infusion force on the liquid to be infused;

a first sensor for measuring at least a first parameter indicative of the infusion force;

a second sensor for measuring a second parameter which is variable in accordance with the first parameter;

a controller programmed to perform following operations;

determining at least two values of the first parameter and corresponding values of the second parameter;

verifying whether the values are in a predetermined relation with a reference value;

emitting a signal in consequence of the verification.

2. The device of claim 1, wherein the determining stage comprises determining at least one variation of the first parameter and at least one variation of the second parameter.

3. The device of claim 1, wherein the second parameter is function of a position of a mobile part of the actuator.

4. The device of claim 1, wherein the verifying operation comprises verifying whether a ratio between the variation of the first parameter and the variation of the second parameter exceeds a threshold value.

5. The device of claim 4, wherein the controller is programmed to emit an alarm signal if the ratio exceeds the threshold value.

10. The device of claim 1, wherein the first sensor comprises a force transducer.

11. The device of claim 1, wherein the actuator is a linear actuator.

12. The device of claim 1, wherein the actuator comprises a syringe pump.

13. A machine for extracorporeal blood treatment, comprising an infusion device according to claim 1.

14. A machine for extracorporeal blood treatment, comprising an infusion device of an anticoagulant into an extracorporeal blood circuit, the device being realised according to claim 1.

15. The machine of claim 13, predisposed to perform one or more of following treatments:

hemodialysis, pure ultrafiltration, hemofiltration, hemodiafiltration, plasmapheresis, hemoperfusion, therapeutic plasma exchange.

16. A software program comprising instructions for enabling a controller to perform the operations of claim 1.

17. The program of claim 16, memorised on at least one of a magnetic and/or optical recording support, a computer memory, an electric or electromagnetic support, and a read-only memory.

6. A device for infusion of a liquid comprising:

an actuator for exerting an infusion force on the liquid to be infused;

a first sensor for measuring at least a first parameter indicative of or function of the infusion force;

a controller programmed to perform following operations;

verifying if the first measured parameter is in a predetermined relation with a reference value;

emitting a signal in consequence of the verification.

7. The device of claim 6, wherein the reference value is determined on a basis of at least one value detected in a stabilisation condition of the first parameter.

8. The device of claim 7, wherein the stabilisation condition is defined on a basis of a verification of a relation between a variation in the first parameter according to a time and a predetermined value.

9. The device of claim 7, wherein the controller is programmed to verify whether the first parameter satisfies two predetermined relations with two reference values, one greater and one smaller than the stabilisation value.

18. A control procedure for an infusion device, the infusion device exerting an infusion force on a liquid to be infused, the infusion force being a function of at least one other parameter, the procedure comprising a stage of determining at least one value indicative of or function of a derivative of the infusion force as a function of the parameter.

19. The procedure of claim 18, comprising a stage of signalling an anomalous situation when said value exceeds a maximum threshold.

20. The procedure of claim 18, wherein the one other parameter is indicative of or function of a position of a mobile part of the infusion device.

21. A control procedure for an infusion device, comprising stages of:

determining at least one variation of a first parameter indicative of or function of an infusion force exerted by the infusion device, and at least one corresponding variation of a second parameter which is indicative of an operating situation of the infusion device;

verifying whether the variations are in a predetermined relation with a reference value;

emitting a signal in consequence of the verification.

22. The procedure of claim 21, wherein an alarm signal is emitted if a ratio between the variations exceeds a threshold value.

25. The procedure of claim 21, wherein the second parameter is correlated to a position of a mobile part of the infusion device.

23. A control procedure of an infusion device comprising stages of:

determining at least two values of a first parameter indicative of or function of an infusion force exerted by the infusion device, and at least two corresponding values of a second parameter indicating an operating situation of the infusion device;

verifying whether the values are in a predetermined relation with a reference value;

emitting a signal in consequence of the verification.

24. The procedure of claim 23, wherein an alarm signal is emitted if a ratio between a variation in the first parameter and a variation in the second parameter exceeds a threshold value.