US 12,029,580 B2
Providing a parameter which indicates a loss of consciousness of a patient under anesthesia
Susanne Koch, Berlin (DE); and Claudia Spies, Berlin (DE)
Assigned to COVIDIEN LP, Mansfield, MA (US)
Appl. No. 17/049,479
Filed by Covidien LP, Mansfield, MA (US)
PCT Filed Apr. 26, 2019, PCT No. PCT/EP2019/060788
§ 371(c)(1), (2) Date Oct. 21, 2020,
PCT Pub. No. WO2019/207130, PCT Pub. Date Oct. 31, 2019.
Claims priority of application No. 102018110275.5 (DE), filed on Apr. 27, 2018.
Prior Publication US 2021/0244353 A1, Aug. 12, 2021
Int. Cl. A61B 5/00 (2006.01); A61B 5/291 (2021.01); A61B 5/372 (2021.01); A61B 5/384 (2021.01)
CPC A61B 5/4821 (2013.01) [A61B 5/291 (2021.01); A61B 5/372 (2021.01); A61B 5/384 (2021.01); A61B 5/7225 (2013.01)] 21 Claims
OG exemplary drawing
 
1. A method for providing a parameter that indicates a loss of consciousness in a patient under anesthetic, wherein the method comprises:
recording a plurality of electroencephalography (EEG) signals from a head of the patient, wherein the plurality of EEG signals are recorded during a period of time that begins before an anesthesia-inducing medicine is administered to the patient and ends after the loss of consciousness in the patient under anesthetic;
determining a plurality of spectral cutoff frequencies in the period of time based on the plurality of EEG signals, wherein each of the plurality of spectral cutoff frequencies indicates a frequency within a range of frequencies associated with an EEG signal of the plurality of EEG signals at which a portion of the range of frequencies below the frequency comprises 95% of an overall power of a frequency spectrum associated with the range of frequencies is found;
determining an absolute minimum associated with the plurality of spectral cutoff frequencies in the period of time, wherein the absolute minimum comprises a lowest spectral cutoff frequency of the plurality of spectral cutoff frequencies in the period of time; and
providing the parameter that indicates the loss of consciousness in the patient based on the absolute minimum, wherein the parameter is associated with a point in time within the period of time at which the absolute minimum occurs.