Pathological state detection using dynamically determined body index range values

Abstract

We report method of detecting a pathological body state of a patient, comprising receiving a body signal of the patient; determining a body index from said body signal; determining an activity level of said patient; determining a value range for said body index for said patient, based at least in part on said activity level; comparing said body index to said value range; and detecting a pathological state when said body index is outside said value range. We also report a medical device system configured to implement the method. We also report a non-transitory computer readable program storage unit encoded with instructions that, when executed by a computer, perform the method.

What is claimed: 
     
         1 . A method for detecting a pathological body state of a patient, comprising:
 receiving a first body signal of the patient;   determining a first body index from the first body signal;   determining an activity level of the patient;   determining a non-pathological range for the first body index, based at least in part on the activity level;   comparing the first body index to the non-pathological range for the first body index; detecting a pathological body state when the first body index is outside the non-pathological range.   
     
     
         2 . The method of  claim 1 , further comprising
 determining at least a second body index;   determining a non-pathological range for the second body index, based at least in part on the activity level;   comparing the second body index to the non-pathological range for the second body index; and   wherein detecting the pathological state comprises detecting the pathological state when the first body index is outside the non-pathological range for the first body index and the second body index is outside the non-pathological range for the second body index.   
     
     
         3 . The method of  claim 1 , further comprising:
 in response to detecting the pathological state, performing at least one further action selected from issuing a notice of the detecting, delivering a therapy, issuing a warning, logging a time of occurrence of the detecting, logging a response to a therapy, and logging a severity of the pathological state.   
     
     
         4 . The method of  claim 1 , wherein the first body index is selected from heart rate, heart rate rhythm, heart rate variability, blood pressure, respiratory rate, respiratory rhythm, tidal CO 2 , kinetic activity, cognitive activity, dermal activity, arterial pH, cortisol level, catecholamine level, or blood oxygen saturation. 
     
     
         5 . The method of  claim 1 , wherein determining the activity level comprises analyzing a body signal of the patient, wherein the analyzing is performed on sensed data from one or more of an accelerometer, an inclinometer, an electromyography (EMG) sensor, a muscle temperature sensor, an oxygen consumption sensor, a lactic acid accumulation sensor, a sweat sensor, a neurogram sensor, a force transducer, or an ergometer. 
     
     
         6 . The method of  claim 1 , wherein determining the non-pathological body index range is further based at least in part on one or more of a time of day, an environmental condition, a patient's body weight and height, a patient's body mass index, a patient's gender, a patient's age, an indicator of the patient's overall health, or an indicator of the patient's overall fitness. 
     
     
         7 . The method of  claim 1 , wherein the activity level is an activity level for a time window. 
     
     
         8 . The method of  claim 1 , wherein determining the activity level occurs in real time. 
     
     
         9 . The method of  claim 1 , wherein the pathological state is an epileptic event. 
     
     
         10 . The method of  claim 1 , further comprising repeating the steps of determining an activity level of the patient and determining a non-pathological range for the first body index at a time interval ranging from about 100 times per second to about once every four hours. 
     
     
         11 . The method of  claim 1 , wherein determining a non-pathological range for the first body index comprises determining the non-pathological range for the first body index for a first time point based on the patient's activity in a first time window prior to the first time point. 
     
     
         12 . The non-transitory computer readable program storage unit of  claim 12 , wherein the duration of the first time window is from 1 second to 2 hours. 
     
     
         13 . The method of  claim 1  wherein determining a first body index from the first body signal comprises determining a change in the first body index, and wherein detecting the pathological body state when the first body index is outside the non-pathological range comprises determining if the change in the first body index is commensurate with the determined activity level. 
     
     
         14 . A method of determining a pathological state in a patient, comprising:
 receiving data relating to an activity level of the patient;   determining an activity level of the patient based on the data relating to an activity level;   receiving at least one body signal of the patient;   determining at least a first body index based on the at least one body signal;   dynamically determining a reference value range for the at least a first body index based on the activity level;   determining that the patient is in one of a non-pathological state and a pathological state, wherein the patient is determined to be in a non-pathological state if the at least a first body index is within the reference value range for the activity level, and the patient is determined to be in a pathological state if the at least a first body index is outside the reference value range; and   taking at least one further action based on determining that the patient is in a pathological state, wherein the further action is selected from treating the pathological state, issuing a warning to the patient or a caregiver regarding the pathological state, logging the occurrence of the pathological state, logging the response to a therapy, or logging a severity of the pathological state.   
     
     
         15 . The method of  claim 14 , wherein the reference value range comprises one of a non-pathological range and a pathological range. 
     
     
         16 . The method of  claim 14 , wherein the pathological state is an epileptic seizure. 
     
     
         17 . The method of  claim 14 , wherein the at least one body signal is selected from a cardiac signal, a respiratory signal, a blood signal, a dermal signal and an endocrine signal. 
     
     
         18 . The method of  claim 14 , wherein the first body index is selected from:
 a cardiac index based on the cardiac signal, wherein the cardiac index is selected from a heart rate, heart rhythm, a heart rate variability, and a blood pressure;   a respiratory index based on the respiratory signal, wherein the respiratory index is selected from a respiratory rate, respiratory rhythm, blood oxygen saturation, and an end tidal CO 2  concentration;   a dermal index based on the dermal signal, wherein the dermal index is selected from a skin resistivity and a skin conductivity;   a blood index based on the blood signal, wherein the blood index is selected from an arterial pH and a lactic acid concentration; and   an endocrine index based on the endocrine signal, wherein the endocrine signal is selected from a cortisol level and a catecholamine level.   
     
     
         19 . A medical device system, comprising:
 at least one kinetic sensor, each the sensor configured to collect at least one kinetic signal from a patient;   an activity level module configured to determine an activity level of the patient, based at least in part on the at least one kinetic signal;   at least one sensor configured to sense a body signal;   a body index determination module configured to determine at least a first body index based on the sensed body signal;   a body index range module, configured to determine a non-pathological body index range for the at least a first body index, based at least in part on the activity level; and   a pathological state determination module, configured to determine that the patient is in one of a non-pathological state and a pathological state, wherein the patient is determined to be in a non-pathological state if the at least a first body index is within the non-pathological body index range for the at least a first body index, and the patient is determined to be in a pathological state if the at least a first body index is outside the non-pathological body index range for the at least a first body index.   
     
     
         20 . The medical device system of  claim 19 , wherein the body signal is selected from heart rate, heart rhythm heart rate variability, blood pressure, respiratory rate, respiratory rhythm, end tidal CO 2 , dermal activity, arterial pH, cortisol level, catecholamine level, or blood oxygen saturation.