Absence of electroencephalographic seizure activity in patients treated for head injury with an intracranial pressure–targeted therapy

Abstract

Object. The authors prospectively studied the occurrence of clinical and nonclinical electroencephalographically verified seizures during treatment with an intracranial pressure (ICP)-targeted protocol in patients with traumatic brain injury (TBI).Methods. All patients treated for TBI at the Department of Neurosurgery, University Hospital Umeå, Sweden, were eligible for the study. The inclusion was consecutive and based on the availability of the electroencephalographic (EEG) monitoring equipment. Patients were included irrespective of pupil size, pupil reaction, or level of consciousness as long as their first measured cerebral perfusion pressure was > 10 mm Hg. The patients were treated in a protocol-guided manner with an ICP-targeted treatment based on the Lund concept. The patients were continuously sedated with midazolam, fentanyl, propofol, or thiopental, or combinations thereof. Five-lead continuous EEG monitoring was performed with the electrodes at F3, F4, P3, P4, and a midline reference. Sensitivity was set at 100 μV per cm and filter settings 0.5-70 Hz. Amplitude-integrated EEG recording and relative band power trends were displayed. The trends were analyzed offline by trained clinical neurophysiologists.Results. Forty-seven patients (mean age 40 years) were studied. Their median Glasgow Coma Scale score at the time of sedation and intubation was 6 (range 3-15). In 8.5% of the patients clinical seizures were observed before sedation and intubation. Continuous EEG monitoring was performed for a total of 7334 hours. During this time neither EEG nor clinical seizures were observed.Conclusions. Our protocol-guided ICP targeted treatment seems to protect patients with severe TBI from clinical and subclinical seizures and thus reduces the risk of secondary brain injury. (DOI: 10.3171/2008.4.17538) Key WOrDs • continuous EEG • head injury • seizureAbbreviations used in this paper: AED = antiepileptic drug; BP = blood pressure; cEEG = continuous electroencephalographic; GCS = Glasgow Coma Scale; ICP = intracranial pressure; ICU = intensive care unit; SE = status epilepticus; TBI = traumatic brain injury.

Frequency of Non-convulsive Seizures and Non-convulsive Status Epilepticus in Subarachnoid Hemorrhage Patients in Need of Controlled Ventilation and Sedation

“…We studied the occurrence of subclinical electroencephalographic seizures in patients with severe traumatic brain injury and found, in contrast with other publications, no EEG seizures [6,27,28].…”

The Utility of EEG, SSEP, and Other Neurophysiologic Tools to Guide Neurocritical Care

“…Post-traumatic seizures commonly result in long-term hippocampal atrophy ipsilateral to the seizure focus [27], with hippocampal neuronal loss as the pathologic phenotype [28]. Although investigators have reported a negligible seizure frequency when using the Lund concept method of preventing elevations in intracranial pressure, the success may be attributable to midazolam use as part of a bias to use sedation to prevent intracranial hypertension rather than the intracranial pressure control itself [29]. As a result, the literature supports the routine use of continuous monitoring for seizure detection in patients with TBI, despite the small amount of prevention afforded by 7 days of prophylactic phenytoin [30].…”

S-100B and neuron specific enolase are poor outcome predictors in severe traumatic brain injury treated by an intracranial pressure targeted therapy

“…Severe traumatic brain injury (sTBI) has been treated in our department since the early 1990s with an intracranial pressure (ICP) guided protocol 20 21 22. These guidelines are based on the principles for treatment of sTBI published by Asgeirsson et al in 1994 23…”