The Value Of Mismatch Negativity In The Assessment Of Consciousness Level In Coma Patients

Objectives:Study on the value of MMN amplitude in the assessment of consciousness level in coma patients and the relationship between MMN amplitude and coma recovery scale-revised(CRS-R),also the relationship between MMN amplitude and the level of consciousness(LoCs)score.Methods:Patients of the First Affiliated Hospital of Kunming Medical University admitted in emergency intensive care unit(EICU)from August 2015 to January 2017 were adopted to carry out a clinical prospective study.I also choosed 17 healthy people whose age and gender were matched with the patient group as the normal group.Patients were repeatedly monitored MMN and assessed CRS-R and LOCs score every 5 days since they admitted in EICU after 72 hours until they awaked or discharged,90 days later I carried out the telephone follow-up.According to the level of consciousness,patients were divided into awaked group,vegetative state(VS)group and the minimum state of consciousness(MCS)group to explore the value of MMN amplitude in the assessment of consciousness level in coma patients and the relationship between MMN amplitude and CRS-R,also the relationship between MMN amplitude and LoCs score.Results:At the end of the study,a total of 15 patients were included in the study.Among them,3 patients were included in the awaked group,8 patients were included in the VS group,and 4 patients were included in the MCS group.Compared with the normal group,the MMN amplitudes of VS and MCS group were significantly different(P<0.001);when the patients gradually recoveried from MCS to awake,compared with the normal group,the MMN amplitude did not significantly differ from the normal group;Comparing MMN amplitude?LoC score and CRS-R total scores in the three greoups,the differences were statistically significant(P<0.001),further LSD-t comparison:the differences among the three groups were statistically significant(P<0.001);There was a correlation between MMN amplitude and LoCs score(r=0.978,P<0.001);Also a correlation between MMN amplitude and CRS-R total scores(r=0.926,P<0.001);further regression analysis can obtain the regression equation:Y=0.19 + 2.37x(X=MMN amplitude,Y=LoCs score);A ROC analysis for awaked group's MMN amplitude showed that area under ROC curve is 0.93,0.94 sensitivity and 0.95 specificity in predicting awaking when the optimal threshold is 3.22.A ROC analysis for MCS group's MMN amplitude showed that area under ROC curve is 0.96,0.98 sensitivity and 0.99 specificity in predicting MCS when the optimal threshold is 2.23.A ROC analysis for VS group's MMN amplitude showed that area under ROC curve is 0.94,0.96 sensitivity and 0.97 specificity in predicting VS when the optimal threshold is 1.21.Conclusions:1?With the gradual increase of the MMN amplitude,the consciousness level of coma patients gradually improved,too;2?The MMN amplitude was correlated with the LoCs score and the CRS-R toal scores in assessing the level of consciousness of patients with coma,which could be used as an objective index to evaluate the level of consciousness of patients with coma.