Application Of Multiple Electrophysiological Techniques In The Prognostic Evaluation Of Coma

Objective 1.To explore the predictive efficacy and characteristic changes of combined multiple electrophysiological techniques for prognosis assessment of comatose patients with structural and non-structural etiology.2.To explore the value of combined multiple predictors on the predictive prognosis of comatose patients.Methods The study enrolled 175 comatose patients,116 cases due to structural brain damage and 59 to non-structural diseases.The collected data covered serological and clinical information,and multiple electrophysiological examinations(SLSEP,BAEP,EEG)during 1 to 7 days after the onset.Observation variables were GCS,FOUR,bilateral pupillary light reflex,GM/WM and midline shift of the head CT,bilateral SLSEP N20 wave presence,bilateral V wave presence,III-V/I-III interpeak latency ratio of BAEP,EEG reactivity,EEG grading standard of Synek and neuron-specific-enolase(NSE).Outcomes after 3 months were estimated using the Glasgow Outcome Scale(GOS).A score of 3 to 5 was considered as good outcome,and 1 to 2 as poor.To compare the values and differences of multiple electrophysiological examinations,NSE and clinical assessments in predicting the prognosis of coma of structural and non--structural etiology.Results Poor prognosis was reported in 77 patients with structural coma and 48 patients with non-structural coma.1.Statistical results showed that GCS score,FOUR,bilateral pupillary light reflex,bilateral SLSEP N20 wave presence,III-V/I-III interpeak latency ratio,EEG reactivity and EEG grading were prognostic predictors for structural coma group.FOUR,N20 wave,V wave,EEG reactivity and Synek grading,NSE,and GM/WM were prognostic predictors for non-structural coma.2.The prediction accuracy of structural coma group was higher in bilateral pupillary light reflex(AUC=0.705)in clinical predictors and bilateral SLSEP N20 wave presence in electrophysiological predictors(AUC=0.654),while in non-structural coma group,with higher accuracy in FOUR(AUC=0.785)and Synek grading(AUC=0.738).3.Prognostic accuracy of the predictors showed that structural coma group has a better sensitivity in EEG reactivity(82.9%,95% CI: 72.1%-90.2%)and bilateral SLSEP N20 wave presence(74.7%,95% CI: 63.1%-83.7%),and a better specificity(84.6%,95% CI: 68.8%-93.6%)and high positive predictive value(87.5%,95% CI: 74.1%-94.8%)in pupillary light reflex.In non-structural coma group,with higher sensitivity in EEG reactivity(97.9%,95% CI: 87.3%-99.9%)and EEG Synek grading(87.2%,95% CI: 73.6%-94.7%),and a better specificityin NSE(90.0%,95% CI: 54.1%-99.5%).4.Compared with single predictor,the accuracy of predictive prognosis of combined electrophysiological predictors were improved,in structural coma group,a combination of multiple electrophysiology methods reported an area under the ROC curve(AUC)of 0.771(95%CI 0.683-0.860),a combination of clinical predictors and multiple electrophysiology methods reported an area under the ROC curve(AUC)of 0.805(95%CI 0.725-0.885),in non-structural coma group,a combination of multiple electrophysiology methods reported AUC of 0.920(95%CI 0.844-0.996),a combination of clinical predictors and multiple electrophysiology methods reported AUC of 0.968(95%CI 0.928-1.000).Conclusions Multiple electrophysiological examinations have different predictive efficacy in comas of different etiologies.The N20 wave of SLSEP was a better prognostic indicators for comas of structural etiology,while EEG reactivity and grading are more reliable for prognostic prediction of comas by metabolic diseases.It can improve the accuracy of prognosis prediction of coma patients by employing electrophysiology methods combined with clinical factors.