REHABILITATION OF PATIENTS WITH ENCEPHALOPATHY CAUSED BY ACUTE CHEMICAL AGENTS POISONING. P300 OF AUDITORY EVENT RELATED POTENTIALS AND ELECTROENCEPHALOGRAPHY

RELEVANCE. Patients with encephalopathy due to acute chemical agents poisoning have some brain functioning changes and a cognitive impairment during the rehabilitation program. These changes require correction of appropriate diagnostic protocol and treatment.

AIM. The aim of this study was to estimate changes of electroencephalography (EEG) and the P3 component of the event related potential (P300 ERP) that are observed in patients with encephalopathy due to acute chemical agents poisoning during stage of rehabilitation.

MATERIAL AND METHODS. The study was included 25 patients (age 37 (32; 51)) poisoned different kind of neurotoxic substances (drugs, ethanol) and complicated by toxic and hypoxic encephalopathy. They have got the treatment of encephalopathy by mexidol intravenously, mesodiencephalic modulation (MDM) and hyperbaric oxygen therapy (HBOT). All patients were recoded EEG (electroencephalograph of “MBN” company, Russia) and P300 ERP (“Neuron-Spectrum-5/EP” of “Neurosoft”, Russia) according to the international recommendations of clinical neurophysiologists. Neuropsychological testing was used for the assessment of cognitive functions.

RESULTS. There were some disturbances in primary electroencephalograms of all subjects. The follow-up EEG recording showed the main group of patients who had got the treatment (mexidol, MDM, HBOT) had more often (11 patients) the EEG improvements compared to the controls (1 patient). The main group had more rarely the EEG impairments compared to the control group. 6 patients of main group and 3 patients of controls did not have EEG changes during the follow-up EEG recordings. All controls and 17 patients of the main group patients had different cognitive disturbances. After the treatment 15 patients of the main group had improved on neuropsychological tests (MMSE, Munsterberg test, Schulte table, Number Connecting Test). They also had a decrease in the N200, P300 peak latency and an increase in the N200, P300 peak amplitude. Only 3 patients of controls had improved on neuropsychological tests.

CONCLUSION. The results of this study show that mexidol, MDM, HBOT using in the treatment of patients with acute chemical agents poisoning leads to the improvement of brain state and cognitive function compared to the controls. The findings of study have allowed making a preliminary conclusion that using in the treatment this kind of patients the combination HBOT+mexidol or MDM+HBOT+mexidol improves the results of neuropsychological examination. 

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