Predicting the prognosis for comatose patients: somatosensory evoked potentials combined with event-related potentials / 中华神经科杂志

ABSTRACT

Objective To explore the effectiveness of using somatosensory evoked potentials (SEPs) combined with event-related potentials (ERPs) to predict the prognosis of comatose patients in neurologic intensive care units (N-ICU).Methods A prospective cohort study was conducted in 53 comatose patients enrolled from the Department of Neurology,Xuanwu Hospital of Capital Medical University from January 2011 to June 2014.Short-latency somatosensory evoked potentials (SLSEP),middle-latency somatosensory evoked potentials (MLSEP),N100,and mismatch negative (MMN) were recorded in these comatose patients in N-ICU within one week after coma onset.All patients were evaluated with Glasgow Outcome Scale (GOS) in 3 months after onset.GOS grades 3 to 5 were considered the good outcome; while GOS grades 1 and 2 were considered poor.SLSEP,MLSEP,N100 and MMN were also recorded in 30 healthy controls.The consistency between SLSEP,MLSEP,N100,MMN,and prognosis,as well as the prognostic authenticity of SLSEP,MLSEP,N100 and MMN were analyzed.Results The amplitude was smaller and the latency became longer in comatose patients,compared with healthy controls.The latency of N20,N60,N100 and MMN in patients with good outcome was (21.73 ±2.91) ms,(68.67 ±7.60) ms,(114.81 ±21.60) ms and (194.10 ±55.31) ms,respectively.And the latency of N20,N60,N100 and MMN in patients with poor outcome was (20.74 ±2.05) ms,(64.20 ±5.29) ms,(109.74 ±21.30) ms and (181.00 ± 50.32) ms,respectively.The consistency between poor outcome and absence of evoked potentials for N20,N60,N100 and MMN was satisfactory (x2 =14.60,10.59,14.46,18.12 respectively,all P ＜ 0.05).When combined SEPs with ERPs,the sensitivity was 85.2％,specificity was 74.2％,and general correct rate was 86.8％,respectively,for good outcome; the sensitivity was 74.2％,specificity was 85.2％,and general correct rate was 86.8％,respectively,for poor outcome.Conclusions The bilateral absence of N20 has a good power for predicting the poor outcome in comatose patients,while the bilateral existence of N60,N100 and MMN has a good power for predicting the good outcome.The combined use of SEPs and ERPs in evaluating and predicting the outcomes in comatose patients is suggested.