Inhaled anesthetic agent therapy and delivery system

• US 8,267,081 B2
• Filed: 02/20/2009
• Issued: 09/18/2012
• Est. Priority Date: 02/20/2009
• Status: Expired due to Fees

• Current Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Original Assignee: Baxter Healthcare SA (Baxter International Inc.), Baxter International Inc.
• Inventors: Hurst, William S., Wu, Haiming, Flanagan, Craig T., Sheu, Lien-Lung, Block, Thomas A.
• Primary Examiner(s): Anderson, Lynne
• Assistant Examiner(s): Hairell, Aundria
• Application Number:
  US12/389,802
• Publication Number:
  US 20100212668A1
• Time in Patent Office: 1,306 Days
• Field of Search: 128/200.24, 128/205.11, 128/205.27, 128/205.28, 128/203.16, 128/203.12, 128/204.18, 128/205.12
• US Class Current: 128/203.16
• CPC Class Codes: A61M 11/04 operated by the vapour pressure of the liquid to be sprayed or atomised air-humidification, e.g. "room humidifiers" F24F6/00
• CPC Class Codes: A61M 16/0093 by adsorption, absorption or filtration
• CPC Class Codes: A61M 16/04 Tracheal tubes catheters in general A61M25/00
• CPC Class Codes: A61M 16/0833 T- or Y-type connectors, e.g. Y-piece
• CPC Class Codes: A61M 16/104 specially adapted for anaesthetics A61M16/18 takes precedence
• CPC Class Codes: A61M 16/1045 Devices for humidifying or heating the inspired gas by using recovered moisture or heat from the expired gas
• CPC Class Codes: A61M 16/18 Vaporising devices for anaesthetic preparations
• CPC Class Codes: A61M 16/22 Carbon dioxide-absorbing devices ; Other means for removing carbon dioxidecartridges with absorbing substances for respiratory apparatus A62B19/00
• CPC Class Codes: A61M 2016/1035 the anaesthetic agent concentration
• CPC Class Codes: A61M 2202/0007 introduced into the body
• CPC Class Codes: A61M 2202/0208 Oxygen
• CPC Class Codes: A61M 2202/03 Gases in liquid phase, e.g. cryogenic liquids
• CPC Class Codes: A61M 2205/123 with incorporated reservoirs
• CPC Class Codes: A61M 2205/505 Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches
• CPC Class Codes: A61M 2230/437 the anaesthetic agent concentration

Abstract

A therapy utilizing inhaled anesthetic agents (such as desflurane, sevoflurane, isoflurane, or xenon) for the sedation of patients outside of the immediate perioperative space such as in the medical intensive care unit (MICU) and the surgical intensive care unit (SICU). The therapy includes controlled delivery of volatile anesthetic agents to patients undergoing ventilatory support on an ICU ventilator over extended periods of time. A system which provides for the delivery of anesthetic agents includes an anesthetic agent vaporizer element, an anesthetic agent reflector, and a plug-in cassette which contains both a cartridge housing liquid phase volatile anesthetic agent and an anesthetic vapor scrubbing medium.

Claims

1. An anesthetic delivery system for use with a ventilator in communication with a patient circuit WYE and an endotracheal tube, the anesthetic delivery system comprising:

a vaporizer having a cavity therein, the vaporizer including a vaporized anesthesia outlet;

a removable cassette received in the cavity of the vaporizer, the cassette having an interior including a supply of an anesthetic agent and a scrubbing material;

a tube having a first end in communication with the vaporized anesthesia outlet of the vaporizer and a second end configured to be placed in communication with the endotracheal tube, wherein the cassette includes an exhausted ventilator gas inlet through which expelled gas is delivered to the interior of the cassette.

2. The anesthetic delivery system of claim 1, wherein the cassette further includes a scrubbed gas outlet through which exhausted ventilator gas that is first filtered through the scrubbing material is vented to an exterior of the cassette.

3. The anesthetic delivery system of claim 2, wherein the vaporizer includes an inlet port in communication with the exhausted ventilator gas inlet of the cassette and a vent opening in communication with the scrubbed gas outlet.

10. The anesthetic delivery system of claim 1, further comprising a reflector disposed between the patient circuit WYE and the second end of the tube, the reflector including a housing and an adsorbent material disposed within the housing.

11. The anesthetic delivery system of claim 10, wherein the reflector further comprises at least one filter medium disposed between the adsorbent material and a port of the reflector in communication with the second end of the tube.

12. The anesthetic delivery system of claim 10, wherein the reflector further includes at least one heat and moisture exchanger medium.

13. The anesthetic delivery system of claim 1, wherein the vaporizer includes an anesthetic agent sensor in electronic communication with a closed loop controller for regulating a concentration of the anesthetic agent delivered from the vaporizer.

4. An anesthetic delivery system for use with a ventilator in communication with a patient circuit WYE and an endotracheal tube, the anesthetic delivery system comprising:

a vaporizer having a cavity therein, the vaporizer including a vaporized anesthesia outlet;

a removable cassette received in the cavity of the vaporizer, the cassette having an interior including a supply of an anesthetic agent and a scrubbing material;

a tube having a first end in communication with the vaporized anesthesia outlet of the vaporizer and a second end configured to be placed in communication with the endotracheal tube, wherein the removable cassette includes an upper level and a lower level, and the upper level supplies volatile anesthetic agent to the vaporizer and scrubs ventilator exhaust gas of residual volatile anesthetic agent before releasing exhaust gas into the environment.

5. An anesthetic delivery system for use with a ventilator in communication with a patient circuit WYE and an endotracheal tube, the anesthetic delivery system comprising:

a vaporizer having a cavity therein, the vaporizer including a vaporized anesthesia outlet;

a removable cassette received in the cavity of the vaporizer, the cassette having an interior including a supply of an anesthetic agent and a scrubbing material;

a tube having a first end in communication with the vaporized anesthesia outlet of the vaporizer and a second end configured to be placed in communication with the endotracheal tube, wherein the removable cassette includes an upper level and a lower level, and the lower level includes two adsorbent beds, which, when the removable cassette is connected to the vaporizer, allow for a switching of gas flow between the two adsorbent beds.

6. The anesthetic delivery system of claim 5, further including an inhale path that traverses one of the two adsorbent beds of the cassette, and an exhale path that traverses the other of the two adsorbent beds of the cassette.

7. The anesthetic delivery system of claim 6, wherein exhaled volatile anesthetic agent accumulates in the adsorbent bed of the exhale path until a breakthrough occurs in the exhale path.

8. The anesthetic delivery system of claim 7, wherein the vaporizer switches internal valve states when the breakthrough occurs, placing the two adsorbent beds in the other'"'"'s former pneumatic path, such that a saturated adsorbent bed of the exhale path is in the inhale path and available for release into the inhale path.

9. The anesthetic delivery system of claim 6, wherein the vaporizer repeatedly switches internal valve states each time one of the two adsorbent beds is saturated during delivery of anesthetic agent and a breakthrough occurs in one of the exhale path or the inhale path.