Fluid path impedance assessment for improving fluid delivery performance

Patent metadata

Field	Value
Publication number	US-11826553-B2
Application number	US-202117449122-A
Country	US
Kind code	B2
Filing date	Sep 28, 2021
Priority date	Aug 31, 2017
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

A fluid injector system for delivering a multi-phase fluid injection to a patient and methods of fluid delivery is disclosed. Methods of creating and using a multi-aspect fluid path impedance model of the injector system are used. Modeling and adjustment of factors that affect impedance and prevent or reduce backflow, reduce the likelihood of fluid flow rate spikes and provide more accurate flow rates and mixing ratios of fluids may be repeated or happen essentially continuously during an injection. The adjustments may be determined before the injection or determined and/or adjusted during the injection. The determination may include sensor feedback commonly used in injectors such as pressure and position feedback as well as other sensors. In all cases, the user can be notified of adjustments through on-screen notices and/or through the recordation of the injection data by a control device of the injector at the conclusion of the injection.

First claim

What is claimed is:

1. A method of delivering multiple fluids to a patient via a multiphase injection with a fluid injector, comprising:
injecting a first fluid during a first phase of the injection with a first pressure limit imposed by the fluid injector, wherein the first fluid has a first viscosity; and
injecting a second fluid during a second phase of the injection with a second pressure limit imposed by the fluid injector, wherein the second fluid has a second viscosity; and
varying a pressure limit of the fluid injector from the first pressure limit to the second pressure limit during a transition from the first phase to the second phase,
wherein the first viscosity is greater than the second viscosity,
wherein the second pressure limit is less than the first pressure limit to minimize a flow rate fluctuation in a fluid path at the transition from the first phase to the second phase, and
wherein the second pressure limit is derived from at least one of a table or an equation or a pressure measured during the second phase; and
deriving a third pressure limit from the at least one of the table or the equation or the pressure measured during the first phase that is different from the first pressure limit and the second pressure limit and then applying the second pressure limit while injecting an initial amount of the second fluid; and applying the third pressure limit while injecting a remaining amount of the second fluid.

2. The method of claim 1 , wherein the injecting the second fluid during the second phase of the injection with the second pressure limit comprises injecting the second fluid at the second pressure limit for a duration of the second phase.

3. The method of claim 1 , wherein the second pressure limit is based upon at least one parameter of the fluid delivery system, wherein the at least one parameter is selected from a group comprising fluid type, fluid viscosity, catheter size, desired flow rate, system capacitance, and system impedance.

4. The method of claim 1 wherein the second pressure limit is determined based on a position of a piston within a syringe containing the second fluid.

5. The method of claim 1 , further comprising:
determining a flow rate for the second fluid based on the second pressure limit.

6. The method of claim 1 , further comprising:
pre-pressurizing a second syringe containing the second fluid prior to injecting the second fluid.

7. The method of claim 1 , further comprising:
applying the second pressure limit while injecting an initial amount of the second fluid; and
applying the first pressure limit while injecting a remaining amount of the second fluid.

8. The method of claim 1 , wherein the third pressure limit is based upon at least one parameter of the fluid delivery system, wherein the at least one parameter is selected from a group comprising fluid type, fluid viscosity, catheter size, desired flow rate, system capacitance, and system impedance.

9. The method of claim 1 , further comprising:
gradually transitioning from the first pressure limit to the second pressure limit during the transition from the first phase to the second phase over a pre-determined transition time.

10. The method of claim 9 , wherein the transition comprises a decrease in a flow rate of the first fluid and an increase in a flow rate of the second fluid.

11. The method of claim 1 , wherein the first pressure limit is a safety pressure limit.

12. The method of claim 1 , wherein the equation is determined by a regression analysis of maximum pressure within the fluid injector at a plurality of different flow rates.

13. The method of claim 1 , further comprising:
displaying a change to at least one of the first pressure limit, the second pressure limit, a flow rate of the first fluid, and a second flow rate of the second fluid.

14. The method of claim 3 , wherein the at least one parameter is system capacitance, and
wherein the system capacitance is determined from a model of system capacitance as a function of:
pressure within a syringe containing the second fluid; and
position of a piston within the syringe.

15. The method of claim 1 , further comprising:
generating an impedance model after injecting the second fluid; and
determining an actual fluid delivery profile based at least partly on the impedance model.

16. The method of claim 15 , further comprising:
generating an image of the patient using at least one of CT, MR, nuclear, ultrasonic, and angiography imaging; and
determining the actual fluid delivery profile based at least partly on the image.

17. The method of claim 1 , further comprising:
applying a lower limit to a flow rate of the first fluid to prevent an injector motor speed from falling below a given percentage of a set speed for an injection procedure.

18. The method of claim 1 , wherein the first fluid is an imaging contrast agent and the second fluid is saline.

Assignees

• Bayer Healthcare Llc

Inventors

• Uber Iii Arthur
• Marsh Chelsea
• Barone William
• Mcdermott Michael
• Newing Timothy
• Spohn Michael
• Delbrugge Vince
• Schriver Ralph
• Cowan Kevin
• Griffiths David

Classifications

• A61M5/31535 Primary

  Means improving security or handling thereof, e.g. blocking means, means preventing insufficient dosing, means allowing correction of overset dose · CPC title

• A61M5/31596

  comprising means for injection of two or more media, e.g. by mixing · CPC title

• A61M5/3221

  Constructional features thereof, e.g. to improve manipulation or functioning · CPC title

• G16H20/17

  delivered via infusion or injection · CPC title

• A61M2205/3334

  Measuring or controlling the flow rate · CPC title