[The cerebral function monitoring in severe cerebral vascular disease]

To evaluate the value of combined evoked potential, continuous EEG with transcranial Doppler to monitor the cases of severe cerebral vascular disease.

32 cases of severe cerebral vascular disease were admitted to the hospital and divided into severe or moderate groups based on the GCS (< or = or > 8) when the patients were admitted. BAEP and SEP were used to for monitoring of brain and brainstem functions. The BAEP and SEP results were divided into grade I, grade II and grade III according to Cant's classification. Continuous EEG monitored all patients by bedside. The EEG findings were divided into 6 grades based on Young's criteria. TCD monitoring by using bilateral 2 MHz Probes with probe holder were lasted at least 30 minutes per day through temporal windows and eye windows to explore the velocity of cerebral artery. The patients were classified into three groups according to the velocities, i.e. (1) the group with elevated velocity, (2) the group with reduced velocity, and (3) the group with normal velocity. The association among the brain and brain stem function, cortex function and cerebral flow velocity was analyzed with patient outcome in the two groups.

(1) The mortality of the patients in the severe group was 42.86%, significantly higher than that in the group of moderate symptom (22.22%). The survivors with good outcome accounted for 33.33% in the moderate group, and those with independent disability accounted for 44.44% in the moderate group, much better than those in the severe group. (2) The numbers of the patients with III grade SEP and BAEP results in the severe group were higher than those in the moderate group. The mortality of the patients with III grade SEP and BAEP results was high and the most of survivors were found with obvious disability in outcome. The patients with grade I SEP and BAEP results showed a better outcome. (3) 32 patients of cerebral vascular disease were monitored with continuous EEG monitoring by bedside. The results revealed that the mortality of the patients with grade II EEG results was much higher than that of the patients with grade I EEG results. (4) The association of the brain blood flow velocity, either increased or decreased or within normal range was uncertain (all P > 0.05).

The cerebral function of patients of severe cerebral vascular disease may be estimated precisely and objectively by using continuous monitoring of SEP, BAEP and EEG at bedside, which will provide valuable information about patient's prognosis and treatment.