Self-normed brain state monitoring

Claim 1

A machine-implemented method for monitoring the occurrence and ascribed medical significance of changes in a patient undergoing a medical procedure relative to a prior state of the patient at a time selected for medical relevance to the planned procedure after administration of anesthesia, comprising: electrically measuring brain functions of the patient which are selected for medical relevance to a medical procedure which the patient is to undergo, at said time at which the patient is in a state selected for medical relevance to the procedure, said selected state being after administration of anesthesia; processing the measurements to produce a self-norm comprising, for each brain function, a respective statistically and medically significant mean measurement and a respective statistically and medically significant standard deviation or variance measurement; electrically measuring the same brain functions of the same patient during the said procedure, at each of a sequence of time intervals selected for medical relevance to the procedure; testing each new set of measurements for statistically and medically significant change from the self-norm; converting each significant change to a dimensionless probability of significant deviation and combining at least two of the said probabilities through vector addition into a single vector-form indication of said medically significant change; and producing a tangible indication of the vector-form indication of the significant change, said tangible indication conveying information both as to the occurrence of a change and as to the ascribed medical significance of the change itself and the persistence of the change.

Claim 3

A method of monitoring the occurrence and ascribed medical significance of changes in a patient undergoing a medical procedure relative to a prior state of the patient at a time selected for medical relevance to the planned procedure, comprising the steps of: selecting a patient state at a time after administration of anesthesia selected for medical relevance to a future medical procedure and electrically measuring brain functions of the patient which are also selected for medical relevance to the procedure; processing the measurements to produce a self-norm comprising, for each brain function, a respective statistically significant mean measurement and a respective statistically significant standard deviation or variance measurement; electrically measuring the same brain functions at each of a sequence of time interevals selected for medical relevance to the procedure, and testing each new set of measurements with respect to the self-norm to obtain significant changes; converting each significant change to a dimensionless probability of significant deviation and combining at least two of the said probabilities through vector addition into a single vector-form indication of said medically significant change; and in case said vector-form indicates the occurrence of a change which is statistically significant and has an ascribed medical significance, producing a tangible indication of the change and, if the test based on the measurements taken in the subsequent time interval indicates that a significant change persists, escalating the nature and ascribed medical significance of the change tangible indication, with each consecutive test which indicates persistence of the change, up to a selected escalated level, but if a new test indicates the absence of a significant change, de-escalating the tangible indication to the one level per test, to a lower level tangible indication of change or to a tangible indication of no change, as the case may be.

Claim 4

A method of monitoring the occurrence and ascribed medical significance of changes in a patient undergoing a medical procedure relative to a prior state of the patient at a time selected for medical relevance to the planned procedure, comprising the steps of: selecting a patient state at a time after administration of anesthesia selected for medical relevance to a future medical procedure and electrically measuring brain functions of the patient which are also selected for medical relevance to the procedure; processing the measurements to produce a self-norm comprising, for each brain function, a respective statistically significant mean measurement and a respective statistically significant standard deviation or variance measurement; electrically measuring the same brain functions at each of a sequence of time interevals selected for medical relevance to the procedure, and testing each new set of measurements with respect to the self-norm to obtain significant changes; converting each significant change to a dimensionless probability of significant deviation and combining at least two of the said probabilities through vector addition into a single vector-form indication of said medically significant change; and in case said vector-form indicates the occurrence of a change which is statistically significant and has an ascribed medical significance, producing a tangible indication of the change and, if the test based on the measurements taken in the subsequent time interval indicates that a significant change persists, escalating the nature and ascribed medical significance of the change tangible indication, with each consecutive test which indicates persistence of the change, up to a selected escalated level, but if a new test indicates the absence of a significant change, de-escalating the tangible indication to the one level per test, to a lower level tangible indication of change or to a tangible indication of no change, as the case may be.