Electroencephalogram (EEG) is a monitoring technology that reflects the change of brain function. It has the advantage of being easy to operate at bedside, and it can provide reliable information for the treatment and prognosis of cerebrovascular disease. EEG monitoring has important clinical significance for the evaluation of brain function in patients with severe cerebrovascular disease. In the ICU environment, Long range EEG monitoring for patients with severe cerebrovascular disease. Observing and analyzing the change rule of EEG in the evolution process of severe cerebrovascular disease is very significant for detecting and judging the evaluation of brain function in patients with severe cerebrovascular disease.
Pathological examination:especially epileptic attack and cerebral ischemia
Epileptic attack: It is difficult to find and diagnose the subclinical seizures in the coma ICU patients, because the patients are often relative or absolutely lack of clinical symptoms. Compared with routine electroencephalogram monitoring (EEG), continuous electroencephalogram monitoring (cEEG) significantly increased the probability of non spasmodic seizures (NCS) and non convulsive status epilepticus (NCSE) in patients with suspected seizures. In patients with continuous EEG monitoring, the seizure rate was 8-48%. The huge range may be due to the different design of different studies (selection bias, etc.), the different ICU patients and the lack of a clear definition of NCS guided by EEG.
Ischemic attack: EEG is a very sensitive method to detect cerebral ischemia. In theory, it can show the change of nerve function and prompt in the reversible stage of cerebral ischemia. Therefore,cEEG can prompt cerebral ischemia changes before obvious clinical symptoms, so as to make early clinical intervention to try to reduce the probability of irreversible cerebral ischemia.
Description of other pathological features except seizures and cerebral ischemia
It can be used to diagnose or eliminate other causes of abnormal mental state, such as delirium and various encephalopathy, outside the seizure. The important difference between delirium and NCS is the progressive awareness and cognitive impairment in the progress of the course of the disease.
EEG can also be used to monitor patients' response to treatment (such as sedation or antiepileptic drugs), and in more than half of EEG patients, monitoring data directly affect the next treatment plan. Although it is not sure how much EEG affects the treatment program, it can still provide the basis for the adjustment of the patient's condition.
Prompt of prognosis
It is difficult to accurately reflect the prognosis of patients with severe neurologic disorders in ICU, so there are a lot of other forecasting methods, including EEG. Most experiments focused on the survival rate after hypoxic and cardiac arrest. Data showed that low voltage in EEG indicates poor prognosis, but most of these data lack external tests.