SYSTEM FOR ELECTROENCEPHALOGRAPHIC DETECTION OF AN INADEQUACY BETWEEN THE STATE OF A PATIENT PLACED UNDER VENTILATORY SUPPORT AND THE SETTING OF THE MACHINE USED FOR THIS SUPPORT, AND USE OF THIS DETECTION TO ADJUST THE SETTING

• US 20130204150A1
• Filed: 07/06/2011
• Published: 08/08/2013
• Est. Priority Date: 07/07/2010
• Status: Active Grant

• Current Assignee: Assistance Publique - Hopitaux De Paris, Centre Hospitalier Régional Universitaire de Lille, Universite Lille 2 Droit et Sante, University Pierre et Marie Curie
• Original Assignee: Assistance Publique - Hopitaux De Paris, Centre Hospitalier Régional Universitaire de Lille, Universite Lille 2 Droit et Sante, University Pierre et Marie Curie
• Inventors: Similowski, Thomas, Raux, Mathieu, Tyvaert, Louise
• Granted Patent: US 9,808,169 B2
• Time in Patent Office: Days
• US Class Current: 600/529
• CPC Class Codes: A61B 5/08 Detecting, measuring or recording devices for evaluating the respiratory organs A61B5/0205 takes precedence
• CPC Class Codes: A61B 5/374 Detecting the frequency distribution of signals, e.g. detecting delta, theta, alpha, beta or gamma waves
• CPC Class Codes: A61B 5/726 using Wavelet transforms
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/0057 Pumps therefor
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 2205/502 User interfaces, e.g. screens or keyboards
• CPC Class Codes: A61M 2230/005 Parameter used as control input for the apparatus
• CPC Class Codes: A61M 2230/10 Electroencephalographic signals
• CPC Class Codes: G06F 2218/12 Classification; Matching

Abstract

The invention relates to a system for electroencephalographic detection of an improper adjustment of a ventilator used on a mammal. The system includes an electroencephalograph, capable of measuring, as a function of time, an electroencephalographic signal representative of a breathing process; and an input for receiving a respiratory initiation signal, different from the electroencephalographic signal, capable of indicating a respiratory initiation time. The detection system further includes means for specifying a beta frequency band comprised between 15 and 30 Hz and with a width comprising between 5 and 10 Hz; means for processing the measured electroencephalographic signal, configured for processing the measured electroencephalographic signal as it is being acquired, in the sole specified beta frequency band; and means for identifying, for each breathing cycle, an improper adjustment of the ventilator from the electroencephalographic signals processed in the sole beta frequency band.

Claims

1. A system for electroencephalographic detection of an improper adjustment of a ventilator used on a mammal, comprising:

an electroencephalograph, capable of measuring, as a function of time, an electroencephalographic signal representative of a breathing process; and

an input receiving a respiratory initiation signal, different from the electroencephalographic signal, capable of indicating a respiratory initiation time;

wherein the detection system further comprises;

a beta band device specifying a beta frequency band comprised between 15 and 30 Hz and with a width comprised between 5 and 10 Hz;

a processor processing the measured electroencephalographic signal, configured for processing the measured electroencephalographic signal as it is being acquired, in the sole specified beta frequency band; and

an identifier identifying, for each breathing cycle, an improper adjustment of the ventilator from the electroencephalographic signals processed in the sole beta frequency band.

2. The electroencephalographic detection system according to claim 1, wherein the identifier identifying the improper adjustment is configured to identify, for each breathing cycle, a possible desynchronization of the electroencephalographic signal in the specified beta frequency band, said desynchronization preceding the respiratory initiation time.

3. The electroencephalographic detection system according to claim 1, wherein the processor is further calculating the instantaneous power of the electroencephalographic signal in the sole beta frequency band, and

the system further comprises storing the calculated instantaneous power.

4. The electroencephalographic detection system according to claim 3, wherein the processor calculates, for each breathing cycle, from the instantaneous power, an average power of the electroencephalographic signal in the sole beta frequency band over a first interval,

wherein the identifier comprises a comparator comparing the instantaneous power calculated in a second interval extending in advance of the respiratory initiation time with the average power calculated over the first interval, the first interval extending in advance of the second interval, and in that the identification means further comprise detection means, capable of detecting, for each breathing cycle, a deviation between the average power calculated in the first interval and the instantaneous power calculated in the second interval.

5. The electroencephalographic detection system according to claim 4, wherein the identifier comprises a trigger capable of triggering an indicator if a deviation is detected for a predetermined number of successive breathing cycles.

6. The electroencephalographic detection system according to claim 1, further comprising, at an input of the beta band device, a beta band determiner determining the beta frequency band, wherein said beta band determiner is also configured to establish a time-frequency map of the electroencephalographic signal measured by the electroencephalograph,

wherein said time-frequency map is capable of indicating the change in the power spectral density of the electroencephalographic signal as a function of time and of the frequency of said signal, and

a frequency detector detecting a frequency band in which the power spectral density of the electroencephalographic signal varies by a value greater than a predetermined threshold, this frequency band corresponding to the beta frequency band specified by the beta band device.

7. The electroencephalographic detection system according to claim 6, wherein the beta band device further comprises a back-averaging device back-averaging point by point the electroencephalographic signal over several identical time intervals, being each set on successive respiratory initiation times, each interval partly extending in advance of the respiratory initiation time, and in that the time-frequency map is obtained from the averaged electroencephalographic signal.

8. A ventilatory support installation, comprises:

a ventilatory support machine, and

a system configured for electroencephalographic detection of an improper adjustment according to claim 1.

9. The ventilatory support installation according to claim 8, further comprising a feedback control loop capable of modifying the adjustment of the ventilator according to the measurements carried out by the system for electroencephalographic detection of an improper adjustment.

10. A method for detecting an improper adjustment of a ventilator used on a mammal, comprising the steps:

receiving, from an electroencephalograph, a measurement of an electroencephalographic signal as a function of time;

determining, for each breathing cycle, a respiratory initiation time;

specifying, using a beta band device, a beta frequency band comprised between 15 and 30 Hz and with a width comprised between 5 and 10 Hz;

processing, with a processor, the measured electroencephalographic signal, as it is being acquired, in the sole beta frequency band; and

identifying, for each breathing cycle, an improper adjustment of the ventilator from the electroencephalographic signal processed in the sole beta frequency band.

11. A computer program product including instructions which, when applied on a computer associated with an electroencephalograph carries out the method according to claim 10.