METHOD AND SYSTEM FOR MONITORING RESPIRATORY GASES DURING ANESTHESIA

• US 20130211207A1
• Filed: 08/16/2012
• Published: 08/15/2013
• Est. Priority Date: 09/09/2011
• Status: Abandoned Application

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: Joseph, Yvonne, Raible, Isabelle, Nelles, Gabriele, Sarpasan, Mustafa, Krasteva, Nadejda
• Application Number:
  US13/587,339
• Publication Number:
  US 20130211207A1
• Time in Patent Office: Days
• US Class Current: 600/301
• CPC Class Codes: A61B 2560/0252 using ambient temperature
• CPC Class Codes: A61B 5/082 Evaluation by breath analysis, e.g. determination of the chemical composition of exhaled breath A61B5/083, A61B5/091 take precedence
• CPC Class Codes: A61B 5/097 Devices for facilitating collection of breath or for directing breath into or through measuring devices
• CPC Class Codes: A61M 16/01 specially adapted for anaesthetising A61M16/104, A61M16/18 take precedence
• CPC Class Codes: A61M 16/021 operated by electrical means A61M16/202 – A61M16/205 take precedence
• CPC Class Codes: A61M 16/085 Gas sampling
• CPC Class Codes: A61M 16/104 specially adapted for anaesthetics A61M16/18 takes precedence
• CPC Class Codes: A61M 16/161 with means for measuring the humidity
• CPC Class Codes: A61M 2016/1025 the O2 concentration
• CPC Class Codes: A61M 2016/1035 the anaesthetic agent concentration
• CPC Class Codes: A61M 2205/0244 Micromachined materials, e.g. made from silicon wafers, microelectromechanical systems [MEMS] or comprising nanotechnology
• CPC Class Codes: A61M 2205/3368 Temperature
• CPC Class Codes: A61M 2230/432 partial CO2 pressure (P-CO2)
• CPC Class Codes: A61M 2230/435 partial O2 pressure (P-O2)
• CPC Class Codes: A61M 2230/437 the anaesthetic agent concentration
• CPC Class Codes: G01N 2033/4975 other than oxygen, carbon dioxide or alcohol, e.g. organic vapours

Abstract

An e-nose device employing chemiresistive sensors with a thin nanoparticle film allows to perform a fast and accurate analysis of respiratory gases during anesthesia in real-time over the entire breathing cycle. A combinatorial selection of nanoparticles and organic linker molecules in the nanoparticle film allows to achieve a high selectivity, which is particularly suitable for detecting a change of anesthetics or analgesics over time.

Claims

1. A system (10) adapted for monitoring respiratory gases during anesthesia, comprising:

a sensor means comprising a sensor array (30) with a plurality of chemiresistive sensors; and

a conduct means adapted for supplying, to said chemiresistive sensors, an inhaled gas of a subject (14) and/or an exhaled gas of said subject (14);

wherein said sensor means are adapted to monitor said inhaled gas of said subject (14) and/or said exhaled gas of said subject (14) by analyzing a gas sample supplied via said conduct means to said chemiresistive sensors;

wherein said chemiresistive sensors comprise a nanoparticle film with a nanoparticle network (32), said nanoparticle network (32) formed of nanoparticles (34) interlinked through linker molecules (36); and

wherein a thickness of said nanoparticle film is no greater than 100 nm, preferably no greater than 50 nm.

2. The system (10) according to claim 1, wherein said nanoparticle network (32) in at least one of said chemiresistive sensors does not comprise a polymer.

3. The system (10) according to claim 1, wherein said linker molecules (36) in at least one of said chemiresistive sensors comprise non-linear polymer molecules or oligomer molecules, in particular dendrimer molecules.

4. The system (10) according to claim 1, wherein said nanoparticles (34) in said nanoparticle network (32) are arranged in a plurality of layers, wherein nanoparticles (34) of adjacent layers are connected by said linker molecules (36).

5. The system (10) according to claim 1, wherein said nanoparticles are metallic nanoparticles (34), and in particular comprise a metal selected from the group consisting of Au, Pt, Ag, Pd, Cu, Ni, Cr, Mo, Zr, Nb, Fe, or any combination of these metals.

6. The system (10) according to claim 1, wherein said sensor array (30) comprises a first group of chemiresistive sensors comprising hydrophilic linker molecules, and/or a second group of chemiresistive sensors comprising hydrophobic linker molecules, and/or a third group of chemiresistive sensors comprising amphiphilic linker molecules.

7. The system (10) according to claim 1, wherein said conduct means are adapted for sidestream connection to an inlet conduct (16), said inlet conduct (16) for supplying an anesthetic gas to said subject (14), and/or for sidestream connection to an outlet conduct (18), said outlet conduct (18) for removing exhaled breath from said subject (14).

8. The system (10) according to claim 1, wherein said conduct means further comprise a reference inlet (26) in fluid communication with said sensor array (30), said reference inlet (26) adapted for supplying a reference gas sample to said chemiresistive sensors.

9. The system (10) according to claim 1, wherein said sensor means comprise a humidity sensor (38) and/or a temperature sensor.

10. The system (10) according to claim 1, wherein said sensor means comprise analyzation means adapted to identify an anesthetic and/or analgesic in said inhaled gas and/or in said exhaled gas, and/or adapted to determine a concentration of an anesthetic and/or analgesic in said inhaled gas and/or said exhaled gas by determining a ratio of a signal provided by a first chemiresistive sensor to a signal provided by a second chemiresistive sensor, said second chemiresistive sensor different from said first chemiresistive sensor.

15. A storage means adapted for storing computer-readable instructions, such that said instructions, when read on a computer connected to a system (10) for monitoring respiratory gases according to claim 1, implement on said system (10) a method according to claim 11.

11. A method for monitoring respiratory gases during anesthesia, comprising the steps of:

providing a sensor means comprising a sensor array (30) with a plurality of chemiresistive sensors;

exposing said chemiresistive sensors to an inhaled gas of a subject (14) and/or to an exhaled gas of said subject (14); and

analyzing said inhaled gas and/or said exhaled gas;

wherein said chemiresistive sensors comprise a nanoparticle film with a nanoparticle network (32), said nanoparticle network (32) formed of nanoparticles (34) interlinked through linker molecules (36);

wherein a thickness of said nanoparticle film is no greater than 100 nm, preferably no greater than 50 nm.

12. The method according to claim 11, further comprising the steps of exposing said chemiresistive sensors to a reference gas sample, and comparing said inhaled gas and/or said exhaled gas to said reference gas sample.

13. The method according to claim 12, wherein said chemiresistive sensors are exposed to said reference gas sample after a predetermined number n of breathing cycles, each said breathing cycle comprising the steps of consecutively exposing said chemiresistive sensors to said inhaled gas of said subject (14) and to said exhaled gas of said subject (14).

14. The method according to claim 11, further comprising a step of identifying an anesthetic and/or analgesic in said inhaled gas and/or said exhaled gas, and/or a step of determining a concentration of an anesthetic and/or analgesic in said inhaled gas and/or said exhaled gas by determining a ratio of a signal provided by a first chemiresistive sensor to a signal provided by a second chemiresistive sensor, said second chemiresistive sensor being different from said first chemiresistive sensor.