Contrast media injector

• US 5,249,579 A
• Filed: 12/20/1990
• Issued: 10/05/1993
• Est. Priority Date: 03/09/1990
• Status: Expired due to Term

• Current Assignee: AngioDynamics, Inc., EZM Incorporated
• Original Assignee: E-Z-EM Incorporated (Bracco SPA)
• Inventors: Hawkins, Irvin F., Goodman, John, Hobbs, Eamonn, Zimmet, Arthur L.
• Primary Examiner(s): Pellegrino, Stephen C.
• Assistant Examiner(s): Rafa, Michael
• Application Number:
  US07/629,180
• Time in Patent Office: 1,020 Days
• Field of Search: 128/655, 128/662.02, 128/747, 601/23, 601/26-28, 601/49, 601/67, 601/30-34
• US Class Current: 600/458
• CPC Class Codes: A61B 18/245 for removing obstructions in blood vessels or calculi
• CPC Class Codes: A61B 5/0215 by means inserted into the body catheters A61M25/00
• CPC Class Codes: A61B 5/411 Detecting or monitoring allergy or intolerance reactions to an allergenic agent or substance
• CPC Class Codes: A61B 6/481 involving the use of contrast agents
• CPC Class Codes: A61B 6/504 for diagnosis of blood vessels, e.g. by angiography
• CPC Class Codes: A61B 6/541 involving acquisition triggered by a physiological signal
• CPC Class Codes: A61M 2202/0007 introduced into the body
• CPC Class Codes: A61M 2202/0225 Carbon oxides, e.g. Carbon dioxide
• CPC Class Codes: A61M 2210/12 Blood circulatory system
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/04 Heartbeat characteristics, e.g. ECG, blood pressure modulation
• CPC Class Codes: A61M 5/007 for contrast media

Abstract

An apparatus is provided to deliver carbon dioxide to an animal in a manner which allows the carbon dioxide to totally displace blood in an area of interest and to thus serve as a contrast media for angiographic procedures, or blood displacement media for angioscopic or laser procedures. The apparatus enables the carbon dioxide to flow at varied flow rates, the varied flow rates correlated to the varied flow rate of blood in the animal'"'"'s vascular system. The flow rate of the carbon dioxide is variable during the course of a single injection.

Claims

1. Apparatus for delivering gas into an animal'"'"'s cardio-vascular system to enable the gas to function as an angiographic contrast medium comprising:

a source of the desired gas,

a catheter adapted to be coupled into the animal'"'"'s cardio-vascular system,

injection control means responsive to the cardiac cycle to provide a first control signal during systole and a second control signal during diastole,

valve means connecting said source to said catheter,

said valve means being responsive to said control signals to provide said gas at a first rate during systole and a second rate during diastole.

2. The apparatus of claim 1 wherein said rate during diastole is a predetermined percentage of said rate during systole.

3. The apparatus of claim 1 further comprising:

volume measuring means to provide a signal to indicate the cumulative volume of gas being injected during an injection procedure, and

shut off means responsive to said volume indicator signal to shut said valve when said volume has reached a predetermined value.

4. An apparatus for injecting gas into an animal in a manner which allows the gas to totally displace blood in an area of interest, the apparatus comprising:

an injector comprising means for connecting to a source of gas;

a catheter comprising mans for connecting to aid injector and through which the gas enters into the animal;

said injector comprising means for varying the flow rate of gas through the injector and the catheter at a first flow rate during systole and a second flow rate during diastole so that a pulsatile flow of gas synchronous to the flow of blood in the animal'"'"'s vascular system is achieved.

5. The apparatus of claim 4 and further comprising means to regulate the pressure of the gas in the apparatus.

6. The apparatus of claim 4 and further comprising means to vent gas from the apparatus.

7. The apparatus of claim 4 and further comprising a plurality of pressure transducers to sense the pressure of the gas at various points in the apparatus to monitor proper functioning of the apparatus for patient safety.

8. The apparatus of claim 4 and further comprising a mass flow sensor to provide the microprocessor with information to determine if the flow rate of gas and amount of gas being delivered is within the input parameters so that the microprocessor can terminate injection where flow rate or volume are not within input parameters.

9. The apparatus of claim 4 wherein said gas is carbon dioxide.

10. The apparatus of claim 9 and further comprising a sterile segment including means for connecting to said injector and said catheter, said sterile segment, for transporting carbon dioxide or saline solution to the catheter, the saline solution preventing clotting of blood in the catheter.

11. The apparatus of claim 9 and further comprising means to sense the presence of contaminants within the apparatus.

12. The apparatus of claim 9 wherein said sensing means senses the presence of oxygen.

13. The apparatus of claim 4 wherein said means flow rate varying includes a valve having a variable orifice and a microprocessor for controlling the orifice size of the valve using selected input data.

14. The apparatus of claim 13 wherein said selected input data includes the length and diameter of the catheter, a first flow rate, the volume of carbon dioxide to be delivered, blood pressure information from the animal and information concerning the animal'"'"'s cardiac cycle.

15. The apparatus of claim 14 and further comprising a plurality of pressure transducers to sense the pressure of the carbon dioxide at various points in the apparatus to monitor proper functioning of the apparatus for patient safety.

16. The apparatus of claim 15 and further comprising a timer.

17. The apparatus of claim 16 wherein said microprocessor comprises means for calculating an expected injection time and comparing it to actual injection time to terminate injection when actual time exceeds expected time.

18. A method of delivering gas into an animal'"'"'s vascular system to enable the gas to function as an angiographic contrast medium, the method including the steps of:

(a) determining a desired flow rate of gas to be delivered during systole;

(b) determining a desired flow rate of gas to be delivered during diastole;

(c) determining the total volume of gas to be delivered;

(d) introducing the gas into the animal using a catheter;

(e) gathering, on an on-going basis, information relating to the animal'"'"'s cardiac cycle;

(f) gathering information relating to the animal'"'"'s blood pressure;

(g) providing a microprocessor with the information determined in steps (a), (b), (c), (e) and (f) and with the length and diameter of the catheter;

(h) providing an injecting apparatus and connecting said apparatus to both said catheter and to a source of gas, the injecting apparatus including means to vary the flow rate of gas through the apparatus, said means being controlled by said microprocessor such that the gas will flow at a first flow rate during systole and at a second flow rate during diastole to totally displace the blood in an area of interest to enable angiographic study.

19. The method of claim 18 wherein said gas is carbon dioxide.

20. The method of claim 19 and further including the step of providing a saline drip to enter the catheter when not injecting carbon dioxide to prevent the clotting of blood.

21. The method of claim 19 and further including the step of purging ambient air from the injecting apparatus.

22. The method of claim 19 and further including the step of establishing a continuous column of carbon dioxide between the injecting apparatus and the animal by injecting a predetermined volume of carbon dioxide through the apparatus.

23. A method of delivering gas into an animal'"'"'s cardiovascular system to enable the gas to function as an angiographic contrast medium comprising the steps of:

injecting the gas at a first predetermined flow rate during systole an a second predetermined flow rate during diastole which synchronizes with systolic and diastolic phases of the cardiac cycle to provide total displacement of blood by the gas in an area of interest.

24. The method of claim 23 wherein said rate during diastole is a predetermined percentage of said rate during systole.

25. The method of claim 24 wherein said predetermined percentage is about twenty percent.

26. The method of claim 23 wherein said step of injecting is undertaken over a plurality of cycles of systole and diastole.

27. The method of claim 23 wherein said step of injecting is undertaken over a plurality of cycles of systole and diastole.