Nebulizing catheter system and methods of use and manufacture

• US 20040084050A1
• Filed: 06/25/2003
• Published: 05/06/2004
• Est. Priority Date: 06/17/1994
• Status: Active Grant

• Current Assignee: Trudell Medical Limited
• Original Assignee: Trudell Medical Limited
• Inventors: Baran, George
• Granted Patent: US 7,469,700 B2
• Time in Patent Office: Days
• US Class Current: 128/207.14
• CPC Class Codes: A61B 90/70 Cleaning devices specially adapted for surgical instruments
• CPC Class Codes: A61M 11/001 Particle size control
• CPC Class Codes: A61M 11/005 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• CPC Class Codes: A61M 11/06 of the injector type
• CPC Class Codes: A61M 15/00 Inhalators drug delivery in endotracheal tubes A61M16/04
• CPC Class Codes: A61M 15/025 Bubble jet droplet ejection devices
• CPC Class Codes: A61M 16/0404 with means for selective or partial lung respiration
• CPC Class Codes: A61M 16/042 with separate conduits for in-and expiration gas, e.g. for limited dead volume
• CPC Class Codes: A61M 16/0463 combined with suction tubes, catheters or the like; Outside connections
• CPC Class Codes: A61M 16/0484 at the distal end
• CPC Class Codes: A61M 16/0486 Multi-lumen tracheal tubes
• CPC Class Codes: A61M 2025/0035 characterized by a variable lumen cross-section by means of a resilient flexible septum or outer wall
• CPC Class Codes: A61M 2025/0036 with more than four lumina
• CPC Class Codes: A61M 2025/0037 characterized by lumina being arranged side-by-side
• CPC Class Codes: A61M 2025/0039 characterized by lumina being arranged coaxially
• CPC Class Codes: A61M 2025/004 characterized by lumina being arranged circumferentially
• CPC Class Codes: A61M 2025/0073 Tip designed for influencing the flow or the flow velocity of the fluid, e.g. inserts for twisted or vortex flow
• CPC Class Codes: A61M 2205/0266 Shape memory materials
• CPC Class Codes: A61M 2209/10 Equipment for cleaning
• CPC Class Codes: A61M 25/0009 Making of catheters or other medical or surgical tubes
• CPC Class Codes: A61M 25/003 : characterized by features relating to least one lumen located at the distal part of the catheter, e.g. filters, plugs or valves catheter tips A61M25/0067
• CPC Class Codes: A61M 25/0068 : Static characteristics of the catheter tip, e.g. shape, atraumatic tip, curved tip or tip structure
• CPC Class Codes: A61M 25/0071 : Multiple separate lumens multiple separate lumens throughout the catheter A61M25/0026
• CPC Class Codes: B67D 7/06 : Details or accessories

Abstract

A method and apparatus for delivering a medicine to a patient via the patient'"'"'s respiratory system with control and efficiency. A nebulization catheter is positioned in the patient'"'"'s respiratory system so that a distal end of the nebulization catheter is in the respiratory system and a proximal end is outside the body. In a first aspect, the nebulization catheter may be used in conjunction with an endotracheal tube and preferably is removable from the endotracheal tube. The nebulization catheter conveys medicine in liquid form to the distal end at which location the medicine is nebulized by a pressurized gas or other nebulizing mechanism. The nebulized medicine is conveyed to the patient'"'"'s lungs by the patient'"'"'s respiration which may be assisted by a ventilator. By producing the aerosol of the liquid medicine at a location inside the patient'"'"'s respiratory system, the nebulizing catheter provides for increased efficiency and control of the dosage of medicine being delivered. In further aspects of the nebulizing catheter apparatus and method, alternative tip constructions, flow pulsation patterns, centering devices, sensing devices, and aspiration features afford greater efficiency and control of aerosolized medicine dosage delivery.

Claims

1. A method for delivering a medicine to a patient'"'"'s respiratory system, comprising:

positioning an endotracheal tube in the patient'"'"'s respiratory system;

positioning a nebulization catheter in the patient'"'"'s respiratory system; and

operating the nebulization catheter to produce an aerosol of the medicine at a distal end of the nebulization catheter while the endotracheal tube is positioned in the patient'"'"'s respiratory system.

2. The method of claim 1 in which the step of operating the nebulization catheter further comprises:

delivering a liquid medicine to a first orifice located at the distal end of the nebulization catheter; and

delivering a pressurized gas to a second orifice located at the distal end of the nebulization catheter in proximity to the first orifice to aerosolize the liquid medicine at the first orifice.

3. The method of claim 1 in which the step of operating the nebulization catheter further comprises:

connecting a pressurized canister containing a mixture of a medicine and a liquid propellant to a proximal end of the nebulization catheter;

delivering the mixture of medicine and liquid propellant through a first lumen of the nebulization catheter to a first distal orifice located at the distal end of the nebulization catheter; and

delivering a pressurized gas through a second lumen of the nebulization catheter to a second orifice located at the distal end of the nebulization catheter in proximity to the first orifice to enhance the aerosolization of the medicine emitted from the first orifice.

4. The method of claim 3 in which the pressurized gas from the second orifice is directed against the medicine and propellant delivered from the first distal orifice.

5. The method of claim 1 further comprising:

centering the nebulization catheter in the endotracheal tube.

6. The method of claim 1 in which the step of positioning a nebulization catheter further comprises:

positioning a nebulization catheter through an auxiliary lumen of the endotracheal tube.

7. The method of claim 1 further comprising:

removing the nebulization catheter while leaving the endotracheal tube in position in the patient'"'"'s respiratory system.

8. The method of claim 2 further comprising the step of:

imparting pulsation to the liquid being delivered.

9. The method of claim 8 in which the pulsation is imparted at a frequency greater than 100 hertz.

10. The method of claim 8 in which the pulsation is applied to a proximal reservoir from which the liquid medicine is supplied.

11. The method of claim 8 in which the pulsation is associated with the delivery of less than approximately 10 microliters of liquid medicine.

12. The method of claim 1 in which the step of operating a nebulization catheter further comprises the step of:

applying an electric signal to the distal end of the nebulization catheter to produce the aerosol from said distal end.

13. The method of claim 1 further comprising:

providing a coaxial airflow to said distal end of said nebulization catheter to constrain aerosol therefrom.

14. The method of claim 1 further comprising:

providing humidification to the patient'"'"'s respiratory system.

15. The method of claim 1 further comprising the step of:

balancing airflow at the distal end of the nebulization catheter by withdrawing air through a vacuum lumen extending through the nebulization catheter.

16. The method of claim 1 in which the step of positioning the nebulization catheter further comprises:

receiving an indication of the position of the nebulization catheter relative to the endotracheal tube.

17. The method of claim 16 in which the indication is a tactile indication.

18. The method of claim 16 in which the step of receiving an indication further comprises:

receiving a indication of a pressure variation at a distal end of the endotracheal tube as the distal end of the nebulization catheter is moved past.

19. A method for delivering a medicine to one or both lungs of a patient who is not intubated, comprising:

positioning a nebulization catheter in the patient'"'"'s respiratory system; and

operating the nebulization catheter to produce an aerosol of the medicine at a distal end of the nebulization catheter.

20. A method of delivering an aerosol of medication to a patient'"'"'s lungs, comprising:

nebulizing the medication at a distal end of a catheter located in the patient'"'"'s respiratory tract, said distal end of said catheter directed in a first direction; and

directing a flow of gas at said nebulized medication in a direction opposite to said first direction.

21. The method of claim 20 in which said first direction in said nebulizing step is a distal direction.

22. The method of claim 20 in which said first direction in said nebulizing step is a proximal direction.

23. The method of claim 20 in which said directing step is further characterized by:

directing a flow of gas from a distal end of an endotracheal tube.

24. The method of claim 20 in which said flow of gas is an inhalation of the patient through an endotracheal tube.

25. A method of delivering a medicine selectively to a bifurcated region of a patient'"'"'s respiratory system, comprising:

positioning a catheter into a branch of the patient'"'"'s respiratory system that leads to a region other than the region to which the medicine is to be delivered;

delivering an airflow through the catheter; and

nebulizing the medicine in the respiratory system proximal of where the airflow is delivered whereby a plume of the nebulized medicine is delivered to the region without the catheter.

26. A catheter for delivering an aerosol of medicine to a patient'"'"'s lungs comprising:

a catheter shaft having a proximal end and a distal end;

a lumen through the catheter shaft and communicating at the proximal end with a port for receiving a medicine in a liquid form and communicating at the distal end with a distal orifice from which the medicine can be discharged;

means for nebulizing the medicine discharged at the distal orifice into an aerosol plume of particles of the medicine; and

means for modifying the aerosol plume of particles of medicine.

27. The catheter of claim 26 wherein the modifying means comprises:

a vacuum orifice located close to the distal orifice from which the medicine is discharged for scavenging air from the nebulized aerosol.

28. The catheter of claim 26 wherein the modifying means comprises:

means for decreasing the velocity of the particles.

29. The catheter of claim 26 wherein the modifying means comprises:

means for increasing the width of the aerosol plume.

30. A catheter system for delivering an aerosol of medicine to a patient'"'"'s lungs comprising:

a catheter shaft having a proximal end and a distal end;

a lumen through the catheter shaft and communicating at the proximal end with a port for receiving a medicine in a liquid form and communicating at the distal end with a distal orifice from which the medicine can be discharged;

means for nebulizing the medicine discharged at the distal orifice;

a flow control apparatus connected to the port, said flow control apparatus comprising;

a flow line communicating with the port, said flow line occupied by the medicine; and

a valve associated with the flow line to cause pulsed delivery of medicine through the flow line.

31. The catheter system of claim 30 in which said flow control apparatus further comprises:

a draw back area associated with the flow line, said draw back area adapted to cause a reversal of flow of medicine through the flow line controller synchronized with the pulsed delivery.

32. A catheter for delivering an aerosol to a patient'"'"'s lungs comprising:

a shaft comprised of;

an outer tubular member defining a first lumen and terminating at a distal end in a first distal orifice;

an inner tubular member defining a second lumen, said inner tubular member located in the first lumen and terminating at a distal end in a second distal orifice;

a manifold connected to a proximal portion of said shaft, said manifold having;

a first port communicating with the first lumen for conveyance of a pressurized gas in an annular region between the inner and outer tubular members; and

a second port communicating with the second lumen for conveyance of a medicine;

said second distal orifice aligned with said first distal orifice to nebulize the medicine from a distal tip of the catheter.

33. The catheter of claim 32 further comprising:

a retractable pin located in said second lumen.

34. A catheter for delivering an aerosol of medicine to a patient'"'"'s lungs comprising:

a catheter shaft having;

a first lumen centrally located in said shaft and adapted for conveying a medicine in liquid form;

a plurality of lumens peripherally located around said first lumen and adapted for conveying a gas;

a distal liquid orifice communicating with said first lumen; and

a plurality of distal gas orifices communicating with said plurality of lumens, said plurality of distal gas orifices aligned with respect to said distal liquid orifice so as to nebulize a liquid medicine discharged from the liquid orifice.

35. A catheter system for delivering an aerosol therapy to a patient'"'"'s lungs comprising:

a stand-alone nebulization catheter having a distal end for insertion into the respiratory system of a patient and a proximal end, said nebulization catheter having;

a catheter shaft;

a gas pressurization lumen extending through said catheter shaft;

a distal gas exit orifice communicating with said gas pressurization lumen, said distal gas exit orifice located at the distal end of said nebulization catheter;

a drug delivery lumen extending along at least a portion of said catheter shaft; and

a distal drug delivery orifice communicating with said drug delivery channel, said distal drug delivery orifice located in proximity to the distal gas exit orifice so that gas exiting from said distal gas exit orifice nebulizes a drug delivered from said distal drug delivery orifice.

36. The catheter system of claim 35 further comprising:

an endotracheal tube having a ventilation lumen in which said nebulization catheter extends.

37. The catheter system of claim 35 further comprising:

an endotracheal tube having a ventilation lumen and an auxiliary lumen located adjacent to said ventilation lumen, said auxiliary lumen having a distal aperture into said ventilation lumen such that a distal end of said auxiliary lumen exits into the ventilation lumen close to a distal end thereof, and further in which said nebulization catheter extends through said auxiliary lumen.

38. The catheter system of claim 35 further comprising:

a centering apparatus located on said catheter shaft close to the distal end.

39. The catheter system of claim 35 in which the centering apparatus has an expanded size and a reduced size and the centering device assumes the expanded size when deployed in an airway passage.

40. The catheter system of claim 35 in which the centering apparatus includes more than one expanded size.

41. The catheter system of claim 35 in which the centering apparatus has an expanded size that can be adjusted after deployment.

42. The catheter system of claim 35 in which said centering apparatus comprises gas centering jets.

43. The catheter system of claim 35 in which the nebulization catheter includes a valve located in at least one of the lumens.

44. The catheter system of claim 43 in which the valve is located in at least one of the distal orifices.

45. The catheter system of claim 43 in which the valve is controlled from the proximal end of the nebulization catheter.

46. The catheter system of claim 43 in which the valve is actuated from the distal end of the catheter.

47. The catheter system of claim 43 in which the valve is formed by an elastically closed tip.

48. The catheter system of claim 35 further comprising a safety stop on a proximal portion of the catheter shaft.

49. The catheter system of claim 35 further comprising:

graduated markings on said catheter shaft.

50. The catheter system of claim 35 further comprising:

luer lock connectors on proximal ports communicating with said gas pressurization lumen and said drug delivery lumen.

51. The catheter system of claim 35 further comprising:

self-sealing proximal ports communicating with said gas pressurization lumen and said drug delivery lumen.

52. The catheter system of claim 35 further comprising:

means for clearing flow blockages at the distal end of the catheter.

53. The catheter system of claim 35 further comprising:

a retractable pin located in at least one of said lumens.

54. The catheter system of claim 35 further comprising:

a stripe on said catheter shaft.

55. The catheter system of claim 35 further comprising:

a baffle located at the distal end of the nebulization catheter in front of the orifices.

56. The catheter system of claim 35 in which said catheter shaft includes a third lumen extending therethrough;

and

a fiber optic scope extending through said third lumen.

57. The catheter system of claim 35 wherein at least a portion of said shaft surrounding said drug delivery lumen is formed of a low compliance material so that flow control at said distal drug delivery orifice of a fluid delivered through said drug delivery lumen is more responsive to flow control at a location proximal thereto.

58. The catheter system of claim 35 further comprising:

a vibrating material located close to said distal orifices.

59. The catheter system of claim 58 in which said vibrating material is a piezoelectric material and further in which said piezoelectric material is connected to at least one electrical conductor that extends through said catheter shaft.

60. A suction catheter for use with an endotracheal tube, said suction catheter sized to be received in a ventilation lumen of the endotracheal tube, said suction catheter having an aspiration lumen for removing mucous from the respiratory tract of an intubated patient, said suction catheter further including:

a gas pressurization lumen extending through a wall of said suction catheter adjacent to said aspiration lumen;

a distal gas exit orifice communicating with said gas pressurization lumen, said distal gas exit orifice located at the distal end of said suction catheter;

a drug delivery lumen extending through the wall of said suction catheter adjacent to said aspiration lumen;

a distal drug delivery orifice communicating with said drug delivery channel, said distal drug delivery orifice located in proximity to the distal gas exit orifice so that gas exiting from said distal gas exit orifice nebulizes a drug delivered from said distal drug delivery orifice.

61. The suction catheter of claim 60 in which said distal gas exit orifice and distal drug delivery orifice are oriented proximally toward a distal suction opening communicating with said aspiration lumen.

62. The suction catheter of claim 60 in which said distal gas exit orifice and distal drug delivery orifice are oriented radially relative to an axis of said suction catheter.

63. A method of forming a catheter for nebulizing a liquid with a gas, the catheter having closely spaced distal orifices sized and spaced apart with low tolerances, comprising the steps of:

providing a relatively large size multilumen extruded polymer tubing;

heating a portion of the tubing to a transition temperature of said tubing;

drawing down said portion of tubing to form a tapered section with a draw down ratio in the range between 2 to 1 and 20 to 1 such that the lumens are increasingly closely spaced in said tapered region; and

forming a plurality of orifices at a distal end of said tapered section, said plurality of orifices being sized to nebulize a liquid delivered through one of said lumens to form an aerosol with a gas delivered through another of said lumens.

64. The method of claim 63 the which the step of forming a plurality of orifices further comprises:

cutting a distal end of the tapered section.

65. The method of claim 63 further comprising:

cutting the tubing to size to form a shaft portion of the nebulization catheter.

66. The method of claim 63 further comprising:

exposing a portion of said tubing to high energy radiation.

67. The method of claim 63 in which said catheter is for use in the respiratory system.

68. The method of claim 63 in which the step of heating further comprises:

heating the tubing to a temperature between a melt state and a glass state of said tubing.