The Assessment of Routine Electroencephalography in Patients with Altered Mental Status

다국어 초록 (Multilingual Abstract)

Purpose: Changes in electroencephalography (EEG) patterns may offer a clue to the cause of altered mental status and suggest the prognoses of patients with such mental status. We aimed to identify the EEG patterns in patients with altered mental status and to correlate EEG findings with clinical prognoses. Materials and Methods: We included 105 patients with altered mental status who underwent EEG. EEG and clinical chart reviews with ongoing patient follow-ups were performed to determine the clinical prognosis of the patients. Clinical data were sorted using the Glasgow Coma Scale (GCS) and Glasgow Outcome Scale (GOS). EEG findings were classified according to a method suggested by Scollo-Lavizzari.
The EEGs were analyzed to find out whether any correlation existed with the prognoses of patients. Results: Nonconvulsive status epilepticus (NCSE) was detected in only three patients (2.9%). Specific EEG patterns were observed in 28 patients. Twenty-nine (27.6%) patients expired, and 45 (42.9%) patients were in a vegetative state. EEG grade and GCS significantly correlated with GOS. EEG grade alone had a correlation with GCS. Patients with a severe EEG finding had a poor prognosis. Conclusion: EEG findings reflect the mental status of patients, and EEG grades are correlated with the clinical prognosis of patients. Although EEG is not frequently performed on patients with altered mental state, it can play a supplemental role in establishing a prognosis. Thus, the use of EEG should be emphasized in clinical setting.

참고문헌 (Reference)

• 1 Synek VM, "Value of a revised EEG coma scale for prognosis after cerebral anoxia and diffuse head injury" 21 : 25-30, 1990
• 2 Young GB, "The EEG in coma" 17 : 473-485, 2000
• 3 Bedell SE, "Survival after cardiopulmonary resuscitation in the hospital" 309 : 569-576, 1983
• 4 Scollo-Lavizzari G, "Prognostic value of EEG in post-anoxic coma after cardiac arrest" 26 : 161-170, 1987
• 5 Towne AR, "Prevalence of nonconvulsive status epilepticus in comatose patients" 54 : 340-345, 2000
• 6 Mullie A, "Predictive value of Glasgow coma score for awakening after out-of-hospital cardiac arrest. Cerebral Resuscitation Study Group of the Belgian Society for Intensive Care" 1 : 137-140, 1988
• 7 Edgren E, "Prediction of outcome after cardiac arrest" 15 : 820-825, 1987
• 8 Sacco RL, "Nontraumatic coma. Glasgow coma score and coma etiology as predictors of 2-week outcome" 47 : 1181-1184, 1990
• 9 Litt B, "Nonconvulsive status epilepticus in the critically ill elderly" 39 : 1194-1202, 1998
• 10 Jirsch J, "Nonconvulsive seizures: developing a rational approach to the diagnosis and management in the critically ill population" 118 : 1660-1670, 2007
• 11 Longstreth WT Jr, "Neurologic recovery after out-of-hospital cardiac arrest" 98 : 588-592, 1983
• 12 Cant BR, "Monitoring by compressed spectral array in prolonged coma" 34 : 35-39, 1984
• 13 Uldry PA, "Modifications in and prognostic value of the EEG in anoxic encephalopathy: 75 cases" 121 : 1453-1459, 1991
• 14 Levy DE, "Knill-Jones RP, Lapinski RH, et al. Prognosis in nontraumatic coma" 94 : 293-301, 1981
• 15 Esteban A, "How is mechanical ventilation employed in the intensive care unit? An international utilization review" 161 : 1450-1458, 2000
• 16 Chiappa KH, "Evaluation and prognostication in coma" 106 : 149-155, 1998
• 17 Kaplan PW, "Electrophysiological prognostication and brain injury from cardiac arrest" 26 : 403-412, 2006
• 18 O’Keefe KP, "Elderly patients with altered mental status" 16 : 701-715, 1998
• 19 Karnaze DS, "EEG monitoring of clinical coma: the compressed spectral array" 32 : 289-292, 1982
• 20 Privitera M, "EEG detection of nontonic-clonic status epilepticus in patients with altered consciousness" 18 : 155-166, 1994
• 21 Pandian JD, "Digital video-electroencephalographic monitoring in the neurological-neurosurgical intensive care unit: clinical features and outcome" 61 : 1090-1094, 2004
• 22 Claassen J, "Detection of electrographic seizures with continuous EEG monitoring in critically ill patients" 62 : 1743-1748, 2004
• 23 McNicoll L, "Delirium in the intensive care unit: occurrence and clinical course in older patients" 51 : 591-598, 2003
• 24 Ely EW, "Delirium as a predictor of mortality in mechanically ventilated patients in the intensive care unit" 291 : 1753-1762, 2004
• 25 Hirsch LJ, "Continuous EEG monitoring in the intensive care unit: an overview" 21 : 332-340, 2004
• 26 Jordan KG, "Continuous EEG and evoked potential monitoring in the neuroscience intensive care unit" 10 : 445-475, 1993
• 27 Feske SK, "Coma and confusional states: emergency diagnosis and management" 16 : 237-256, 1998
• 28 Niskanen M, "Acute physiology and chronic health evaluation (APACHE II) and Glasgow coma scores as predictors of outcome from intensive care after cardiac arrest" 19 : 1465-1473, 1991