Injector auto purge

• US 7,771,389 B2
• Filed: 03/07/2005
• Issued: 08/10/2010
• Est. Priority Date: 02/17/2004
• Status: Expired due to Fees

• Current Assignee: Liebel-Flarsheim Company (Mallinckrodt plc)
• Original Assignee: Mallinckrodt Incorporated (Mallinckrodt plc)
• Inventors: Fago, Frank M., Grispo, Keith M.
• Primary Examiner(s): Sirmons; Kevin C
• Assistant Examiner(s): Gilbert; Andrew M
• Application Number:
  US11/073,892
• Publication Number:
  US 20050182323A1
• Time in Patent Office: 1,982 Days
• Field of Search: 604/67, 604123-127, 604151-155, 604/191, 604/284, 600/432
• US Class Current: 604/123
• CPC Class Codes: A61B 6/548 Remote control of the apparatus or devices
• CPC Class Codes: A61M 2005/1402 Priming
• CPC Class Codes: A61M 2005/1403 Flushing or purging
• CPC Class Codes: A61M 2005/14208 with a programmable infusion control system, characterised by the infusion program
• CPC Class Codes: A61M 2005/14553 comprising a pressure jacket
• CPC Class Codes: A61M 2205/14 Detection of the presence or absence of a tube, a connector or a container in an apparatus
• CPC Class Codes: A61M 2205/17 with redundant control systems
• CPC Class Codes: A61M 2205/215 Tilt detection, e.g. for warning or shut-off
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/52 with memories providing a history of measured variating parameters of apparatus or patient
• CPC Class Codes: A61M 2205/6018 providing set-up signals for the apparatus configuration
• CPC Class Codes: A61M 5/007 for contrast media
• CPC Class Codes: A61M 5/14546 Front-loading type injectors
• CPC Class Codes: A61M 5/14566 with a replaceable reservoir for receiving a piston rod of the pump
• CPC Class Codes: A61M 5/16827 controlling delivery of multiple fluids, e.g. sequencing, mixing or via separate flow-paths infusion of multiple fluids without using a controller A61M5/1407
• CPC Class Codes: A61M 5/36 with means for eliminating or preventing injection or infusion of air into body dialysis systems, blood oxygenators A61M1/14; haemofiltration equipment A61M1/34; automatic tube cut-off A61M39/281
• CPC Class Codes: A61M 5/365 Air detectors A61M5/1684 takes precedence; in extracorporeal blood circuits A61M1/3626
• CPC Class Codes: A61M 5/445 the media being heated in the reservoir, e.g. warming bloodbags
• CPC Class Codes: G16H 40/63 for local operation
• CPC Class Codes: G16H 50/50 for simulation or modelling of medical disorders

Abstract

An auto purge for an intravenous contrast injector of the type having a motor which advances a plunger drive ram and configured for use with a pre-filled or user-filled syringe containing an approximate known amount of air including a processor which causes the motor to move and a memory storing a predetermined purge stop point representative of the approximate known amount of air in the syringe, the injector configured to automatically advance the plunger drive ram an amount substantially equal to the predetermined purge stop point representative of the approximate known amount of air contained in the syringe.

Claims

1. A medical fluid injector comprising:

a syringe having;

a barrel that includes a discharge tip; and

a plunger disposed within and movable relative to the barrel;

a motorized plunger drive ram configured to move the plunger of the syringe within and relative to the barrel of the syringe both toward and away from the discharge tip of the syringe;

a processor which controls movement of the plunger drive ram, the processor configured with a purge sequence designed to force air and/or gas from the syringe via the discharge tip prior to fluidly connecting the syringe with a patient, the processor being further configured with an injection protocol designed to inject medical fluid into a patient when the syringe is fluidly connected with a patient; and

a tilt sensor, wherein an output from the tilt sensor allows for execution of the purge sequence only when the discharge tip of the syringe is pointed upward, wherein an output from the tilt sensor allows for execution of the injection protocol when the discharge tip of the syringe is pointed downward, and wherein the purge sequence includes;

the plunger drive ram moving the plunger within the barrel of the syringe and toward the discharge tip of the syringe an amount substantially equal to a predetermined stop point; and

a low flow rate that is enabled upon the plunger drive ram reaching the predetermined stop point, wherein the low flow rate is a flow rate at which medical fluid is expelled from the discharge tip of the syringe due to the plunger drive ram moving the plunger within the barrel of the syringe, and wherein the low flow rate is no more than about 1 ml/sec.

2. The injector of claim 1, wherein the low flow rate is no more than about 0.5 ml/sec.

3. The injector of claim 1, wherein the medical fluid comprises contrast media.

4. The injector of claim 1, wherein the syringe is designed to allow medical fluid to enter the barrel thereof via the discharge tip.

5. The injector of claim 4, wherein the low flow rate is no more than about 0.5 ml/sec.

6. The injector of claim 4, wherein the syringe is designed to allow medical fluid from within the barrel thereof to be discharged from the syringe via the discharge tip.

7. The injector of claim 1, wherein the syringe is designed to allow medical fluid from within the barrel thereof to be discharged from the syringe via the discharge tip.

8. The injector of claim 5, wherein the low flow rate is no more than about 0.5 ml/sec.

9. The injector of claim 1, wherein the predetermined stop point is based on at least one parameter of the syringe.

10. The injector of claim 9, wherein the low flow rate is no more than about 0.5 ml/sec.

11. The injector of claim 1, wherein the predetermined stop point is user adjusted.

12. The injector of claim 11, wherein the low flow rate is no more than about 0.5 ml/sec.

13. The injector of claim 1, wherein the predetermined stop point is calibrated.

14. The injector of claim 13, wherein the low flow rate is no more than about 0.5 ml/sec.

15. The injector of claim 1, wherein the predetermined stop point is based on historical information.

16. The injector of claim 15, wherein the low flow rate is no more than about 0.5 ml/sec.

17. The injector of claim 1, wherein the low flow rate is applicable to a manual movement control of the injector.

18. The injector of claim 17, wherein the low flow rate is no more than about 0.5 ml/sec.

19. The injector of claim 1, wherein the low flow rate is applicable to an automatic purge of medical fluid from the syringe until the automatic purge is stopped by operator input.

20. The injector of claim 19, wherein the low flow rate is no more than about 0.5 ml/sec.

21. The injector of claim 1, wherein the processor is configured to advance the plunger drive ram to provide an initial flow rate until reaching the predetermined stop point, wherein the initial flow rate is a flow rate at which medical fluid is expelled from the discharge tip of the syringe due to the plunger drive ram moving the plunger within the barrel of the syringe, and wherein the initial flow rate is greater than the low flow rate.

22. A medical fluid injector comprising:

a syringe comprising a barrel and a plunger, the barrel comprising a discharge tip, and the plunger being disposed within and movable relative to the barrel;

a motorized plunger drive ram configured to move the plunger of the syringe within and relative to the barrel of the syringe both toward and away from the discharge tip of the syringe;

a processor which controls movement of the plunger drive ram, the processor being configured with a purge sequence designed to force air and/or gas from the syringe via the discharge tip prior to fluidly connecting the syringe with a patient, the processor being further configured with an injection protocol designed to inject medical fluid into a patient when the syringe is fluidly connected with a patient; and

a tilt sensor, wherein an output from the tilt sensor allows for execution of the purge sequence only when the discharge tip of the syringe is pointed upward, wherein an output from the tilt sensor allows for execution of the injection protocol when the discharge tip of the syringe is pointed downward, and wherein the purge sequence comprises;

a first purge portion comprising a programmed advancement of the plunger drive ram at a first purge flow rate and in a direction that moves the plunger within the barrel of the syringe and toward the discharge tip of the syringe; and

a second purge portion comprising advancement of the plunger drive ram at a second purge flow rate and in a direction that moves the plunger within the barrel of the syringe and toward the discharge tip of the syringe, the second purge portion being available only after completion of the first purge sequence segment, and the second purge flow rate being less than the first purge flow rate.

23. The injector of claim 22, wherein the second purge flow rate is no more than about 1 ml/sec.

24. The injector of claim 22, wherein the first purge portion further comprises terminating advancement of the plunger drive ram, and wherein user input is required to initiate the second purge portion.

25. The injector of claim 24, wherein the first purge portion is terminated upon reaching a predetermined stop point.

26. The injector of claim 22, wherein the second purge portion comprises using a hand-operated movement control associated with the plunger drive ram.

27. The injector of claim 22, wherein the second purge portion comprises a programmed advancement of the plunger drive ram.