Apparatus for delivering drugs to the lungs

• US 5,666,946 A
• Filed: 04/16/1996
• Issued: 09/16/1997
• Est. Priority Date: 07/13/1994
• Status: Expired due to Fees

• Current Assignee: Respirogenics Corporation
• Original Assignee: Respirogenics Corporation
• Inventors: Langenback, Edward G.
• Primary Examiner(s): Millin, Vincent
• Assistant Examiner(s): Deane, Jr., William J.
• Application Number:
  US08/632,964
• Time in Patent Office: 518 Days
• Field of Search: 128/200.14, 128/200.16, 128/203.12, 128/203.24, 128/204.14, 128/200.18, 128/200.21, 128/209.18, 128/204.24, 128/204.25 , 128/204.26, 128/204.27, 128/205.24
• US Class Current: 128/200.16
• CPC Class Codes: A61M 15/0015 located upstream of the dispenser, i.e. not traversed by the product
• CPC Class Codes: A61M 15/0018 with exhalation check valves
• CPC Class Codes: A61M 15/0085 using ultrasonics spraying or atomising liquids using ultrasonic vibrations in general B05B17/06
• CPC Class Codes: A61M 16/14 by mixing different fluids, one of them being in a liquid phase
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2240/00 Specially adapted for neonatal use

Abstract

Apparatus for delivering drugs to the lungs from an ultrasonic nebulizer by inspiration using a ventilator includes a flow system in which the nebulizer is connected in parallel with the series conduit between the ventilator delivery outlet and the ventilator discharge valve and exhaust outlet. One-way valves in parallel flow conduits to the nebulizer provide for bypassing the nebulizer except when the ventilator is in the inspiration phase of its operation, thereby eliminating an important cause of loss of drugs to the ventilator outlet during the expiration phase. The nebulizer, which can also be used for administration of drugs by inhalation (without a ventilator) has a flow regulator which provides for delivery of the drug from the nebulizer only during part of inspiration (or inhalation in a mouth breathing use) and for delivery of gas (air or oxygen) during the remaining part of inspiration (inhalation). A cone in the cap above the vibrating crystal of an ultrasonic nebulizer and improved inlet and outlet porting in the cap improve the conditions in the aerosol chamber of the nebulizer cap to enhance efficiency of drug delivery and reduce drug losses.

Claims

1. Apparatus for delivering drugs to the lungs of a patient comprising

a ventilator having a gas delivery outlet and a gas return inlet, a series conduit leading from the ventilator outlet to the gas return inlet, a return gas outlet valve at the gas return inlet, and a pressure transducer in the ventilator that is adapted to operate the ventilator return gas outlet valve in response to a pressure;

a nebulizer having means for forming an aerosol from a solution of a drug in a liquid and having an inlet and an outlet;

a first conduit connected between the series conduit and the nebulizer inlet and having a one-way valve permitting gas to flow only from the series conduit to the nebulizer inlet;

a second conduit connected between the nebulizer outlet and the series conduit at a location downstream, with respect to the direction of gas flow through the series conduit from the ventilator delivery outlet, from the connection between the first conduit and the series conduit, the second conduit having a one-way valve permitting gas to flow only from the nebulizer to the series conduit;

a pressure sensor conduit connected between the second conduit at a location upstream from the one-way valve in the second conduit, with respect of the direction of gas flow to the series conduit, and the pressure transducer so as to communicate the pressure at said location to the pressure transducer; and

an endotracheal tube connected to the nebulizer outlet and communicating with the second conduit upstream from the one-way valve in the second conduit, with respect of the direction of gas flow to the series conduit.

2. Apparatus according to claim 1 and further comprising flow regulator means interposed in the first conduit to receive gas from the ventilator for regulating the flow of gas from the ventilator outlet to the nebulizer inlet.

3. Apparatus according to claim 2 wherein the regulator means supplies gas from the ventilator outlet to the nebulizer inlet during only a portion of each inspiration of the patient.

4. Apparatus according to claim 3 wherein the regulator means supplies gas to the nebulizer during an initial portion of each inspiration of the patient.

5. Apparatus according to claim 4 and further comprising a bypass conduit connected between the regulator means and the endotracheal tube and wherein the regulator means supplies gas from the ventilator to the bypass conduit during the portion of each inspiration of the patient when the gas from the ventilator is not being supplied to the nebulizer inlet.

6. Apparatus according to claim 5 and further comprising a bypass conduit connected between the regulator means and the endotracheal tube and wherein the regulator means supplies gas from the ventilator to the bypass conduit during the portion of each inspiration of the patient immediately after termination of the supply of gas from the ventilator to the nebulizer inlet.

7. Apparatus according to claim 1 wherein the nebulizer is an ultrasonic nebulizer having a vibrating crystal and a cap, the cap having a wall member presenting a downwardly facing conical surface having its apex centered above the vibrating crystal of the nebulizer.

8. Apparatus according to claim 7 wherein the nebulizer inlet includes a first inlet port in the conical surface of the wall member in spaced apart relation from the apex and the outlet from the cap includes an outlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap inlet.

9. Apparatus according to claim 8 wherein the cap inlet further includes a second inlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap outlet port.

10. Apparatus for delivering drugs to the lungs of a patient comprising

a ventilator having a gas delivery outlet and a gas return inlet, a series conduit leading from the ventilator outlet to the gas return inlet, a return gas outlet valve at the gas return inlet, and a pressure transducer in the ventilator that is adapted to operate the ventilator outlet valve in response to a pressure;

an ultrasonic nebulizer having means including a vibrating crystal for forming an aerosol from a solution of a drug in a liquid and a cap defining a chamber for the aerosol and having an inlet and an outlet;

a first conduit having an inlet end connected to the series conduit;

a one-way valve in the first conduit permitting gas to flow only from the series conduit;

a second conduit having an outlet end connected to the series conduit at a location downstream, with respect to the direction of gas flow through the series conduit from the ventilator delivery outlet, from the connection between the first conduit and the series conduit;

a one-way valve in the second conduit permitting gas to flow only to the series conduit;

a pressure sensor conduit connected between the second conduit at a location upstream from the one-way valve in the second conduit, with respect of the direction of gas flow to the series conduit, and the pressure sensor and communicating the pressure at said location to the pressure transducer;

an endotracheal tube connected to the cap outlet and communicating with the second conduit upstream from the one-way valve in the second conduit, with respect of the direction of gas flow to the series conduit;

and flow regulator means having an inlet connected to the first conduit to receive gas from the ventilator, a first outlet connected to a third conduit, and a second outlet connected to a fourth conduit, one of the third and forth conduits being connected to the cap inlet and the other of the third and fourth conduits being connected to the endotracheal tube, and valve means for conducting gas from the inlet to the first outlet for an initial portion of each inspiration of the patient and for conducting gas to the second outlet during a final portion of each inspiration of the patient.

11. Apparatus according to claim 10 wherein the valve means of the flow regulator means is responsive to gas flow from the ventilator during each inspiration of the patient.

12. Apparatus according to claim 11 wherein the valve means of the flow regulator means includes a movable piston propelled by gas flow from the ventilator and a valve member for changing the flow between the first outlet and the second outlet of the regulator means.

13. Apparatus according to claim 10 wherein the nebulizer cap has a wall member presenting a downwardly facing conical surface having its apex centered above the vibrating crystal of the nebulizer.

14. Apparatus according to claim 13 wherein the cap inlet includes a first inlet port in the conical surface of the wall member in spaced apart relation from the apex and the outlet from the cap includes an outlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap inlet.

15. Apparatus according to claim 14 wherein the cap inlet further includes a second inlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap outlet port.

16. Apparatus for delivering drugs to the lungs of a patient comprising

a ventilator having a gas delivery outlet and a gas return inlet, a series conduit leading from the ventilator outlet to the gas return inlet, a return gas outlet valve at the gas return inlet, and a pressure transducer in the ventilator that is adapted to operate the ventilator return gas outlet valve in response to a pressure;

an ultrasonic nebulizer having means including a vibrating crystal for forming an aerosol from a solution of a drug in a liquid and a cap defining a chamber for the aerosol and having an inlet and an outlet;

an endotracheal tube connected to the cap outlet and adapted to be inserted into the trachea of a patient;

a bypass conduit connected to the endotracheal tube downstream from the cap outlet; and

flow regulating means for regulating gas flows to and from the endotracheal tube including means for establishing a first flow path for a first predetermined time period for conducting a gas from the ventilator outlet through the nebulizer cap to the endotracheal tube, means for establishing a second flow path for a second predetermined time period for conducting a gas from the ventilator outlet through the bypass conduit to the endotracheal tube, and means for establishing a third flow path for a third predetermined time period for conducting a gas from the endotracheal tube to the ventilator gas return inlet.

17. Apparatus according to claim 16 wherein the means for establishing the first flow path includes a first conduit connected to the series conduit, a second conduit connected to the nebulizer cap inlet, a one-way valve in the first conduit permitting gas to flow through the first conduit only from the series conduit, and controllable valve means for connecting the first and second conduits.

18. Apparatus according to claim 16 wherein the controllable valve means includes is a sleeve valve.

19. Apparatus according to claim 18 wherein the controllable valve means further includes a piston driven by gas flow from the ventilator through the first flow path for changing the position of the sleeve valve.

20. Apparatus according to claim 16 wherein the means for establishing the second flow path includes a first conduit connected to the series conduit, a one-way valve in the first conduit permitting gas to flow through the first conduit only from the series conduit, the bypass conduit and a controllable valve connecting the first conduit and the bypass conduit.

21. Apparatus according to claim 20 wherein the controllable valve is a sleeve valve.

22. Apparatus according to claim 21 wherein the controllable valve means further includes a piston driven by gas flow from the ventilator through the second flow path for changing the position of the sleeve valve.

23. Apparatus according to claim 16 wherein the means for establishing the third flow path includes an exhalation conduit connected between the endotracheal tube and the series conduit, and a one-way valve in the exhalation conduit permitting gas to flow only from the endotracheal tube to the series conduit.

24. Apparatus according to claim 16 wherein the nebulizer cap has a wall member presenting a downwardly facing conical surface having its apex centered above a vibrating crystal of the nebulizer.

25. Apparatus according to claim 16 wherein the cap inlet includes a first inlet port in the conical surface of the wall member in spaced apart relation from the apex and the outlet from the cap includes an outlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap inlet.

26. Apparatus according to claim 25 wherein the cap inlet further includes a second inlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap outlet port.

27. In an ultrasonic nebulizer having means including a vibrating crystal for forming an aerosol from a solution of a drug in a liquid, a cap defining a chamber for the aerosol and having an inlet for receiving ambient air and an outlet for discharging a mixture of air and the aerosol, and a mouthpiece connected to the cap outlet, the improvement comprising a first conduit having an outlet connected to the mouthpiece, a second conduit having an outlet connected to the cap inlet, flow regulator means having an inlet for ambient air, a one-way valve in the inlet for permitting ambient air to flow only to the inlet, first and second outlets connected respectively to inlets to the first and second conduits for controlling the flow of air to the first and second conduits such that air flows to one of the first and second conduits during an initial portion of each inhalation by a patient using the nebulizer and air flows to the other of the first and second conduits during the remaining portion of each inhalation by the patient, and an exhalation port connected to the mouthpiece and having a one-way valve for permitting gas to flow only from the mouthpiece upon each exhalation by the patient.

28. The improvement according to claim 27 wherein the nebulizer cap has a wall member presenting a downwardly facing conical surface having its apex centered above a vibrating crystal of the nebulizer.

29. Apparatus according to claim 28 wherein the cap inlet includes a first inlet port in the conical surface of the wall member in spaced apart relation from the apex and the outlet from the cap includes an outlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap inlet.

30. Apparatus according to claim 29 wherein the cap inlet further includes a second inlet port located proximate to the base of the conical surface and generally diametrically opposite from the cap outlet port.

31. Apparatus according to claim 30 wherein the first conduit includes a portion of the cap outlet.

32. Apparatus according to claim 31 wherein the first conduit includes a passage in the cap having a port communicating with the cap outlet port.