A Study On The Evoked Potential For Coma Depth Assessment

At present,coma is a very common clinical manifestation of patients in critical patients.The assessment of the degree of patients’ consciousness disorder will help doctors to master the patients’ condition,which is of great significance to the auxiliary treatment.At the present stage,the coma scale is generally used to evaluate coma.However,the score of the scale depends on the subjective feelings of doctors and patients,and the results often deviate because the objectivity and accuracy cannot meet the needs of clinical treatment.This will lead to improper treatment,so that patients miss the best time for treatment.Therefore,the purpose of this study is to obtain objective and accurate coma assessment methods.With the development of brain imaging technology,Evoked Potentials(EPs)has an important application in the assessment of coma.EPs is a kind of electrical activity recorded in a specific part of the brain after the stimulation of a sensory organ by the outside world.Doctors can objectively observe the pathological changes of patients’ cerebral cortex,brain stem and peripheral nerve structure with EPs,which is convenient,noninvasive and real-time.Combined with the physiological characteristics of comatose patients,auditory evoked potential was used in this study.The experimental paradigm of this project is divided into four parts,each part is a different paradigm,a total of four.The healthy subjects were students from Huaqiao University and comatose patients from The General Hospital of the People’s Liberation Army.The Electroencephalogram(EEG)data of 31 healthy subjects and 11 comatose patients were collected.This experimental study focus on P300 and Mismatch Negativity(MMN).Through a series of processing and analysis of the collected data,it is found that there is a significant difference in P300 and MMN waveform induced by healthy subjects and comatose patients.The distribution of P300 and MMN in comatose patients was smaller than that in healthy subjects,and the peak values of P300 and the average amplitude of MMN in comatose patients were significantly smaller.The peak values of P300 and the average amplitude of MMN can be used as the assessment indicators of coma.The latency of P300 and the latency of MMN also can be used as the assessment indicators of coma.it provides a new basis and method for the assessment of coma.In addition,we observed the asymmetry of Event Related Potentials(ERPs)waveform in healthy subjects,which provided a new way to explore the mechanism of ERPs.