Home > Browse Emergency Issues
<< Seizures and Status Epilepticus: Diagnosis and Management in the Emergency Department
Controversies And Cutting Edge
Neuroimaging In Patients With Alcohol Related Seizures
The term alcohol related seizure refers to either seizure due to alcohol intoxication or its withdrawal. The diagnosis should be made only after work up for other causes of the seizure have been exhausted as this group of patients is more prone to traumatic abnormalities. A 1988 Denver study reported head CT results in 259 patients with a first alcohol-related convulsion. A “clinically significant” lesion was found in 16 (6.2%) patients, seven of whom were alert and had non-focal neurological exams and no history of trauma. Nearly 4% of patients had CT findings that changed clinical management (e.g., subdural hematoma, aneurysm, subarachnoid hemorrhage, and neurocysticercosis). In these patients, the history and physical examination did not predict the CT abnormality. This study emphasizes the importance of avoiding labeling an alcoholic with a first time seizure as having an alcohol withdrawal seizure; it also emphasizes that alcohol is a co-morbidity that drives the need for ED neuroimaging.212
Neuroimaging In Patients With Cocaine Related Seizures
There is one study that suggests that patients who experience a new onset cocaine-related generalized seizure do not require neuroimaging, as long as they do not have a severe headache, recover promptly, and have a normal postictal examination.213 This study only included 35 patients who had both a cocaine related seizure and a head CT and was not part of the formal derivation of a decision rule. In general, cocaine users are at a significantly increased risk of intracranial hemorrhage, as well as trauma and other risk factors; therefore, care must be applied when applying this evidence to clinical practice.
EEG In The ED
An EEG is used to help stratify patients regarding risk of seizure recurrence; thus, it is an important test in deciding who needs to be started on an AED. Inaddition, as discussed above, the EEG helps to identify those patients who are in nonconvulsive status epilepticus. The controversy is when and where an EEG needs to be done; the corollary is, what is the impact of delay in making an EEG based diagnosis? A survey of medical directors in accredited North American EEG laboratories revealed that a majority of facilities required neurologic consultation or other specialized consultation before emergent EEG could be obtained. Furthermore, though many labs claimed to provide “emergent” EEG, there was an average response time of approximately three hours from the time the test was requested, with a range up to 24 hours.214 A multicenter survey revealed that EEG was rarely performed in EDs.7
EEG interpretation is also a specialized field within the specialty of neurology, so it is reasonable to get an EEG only when there is someone available to interpretit. This, along with the generally limited availability of EEG in the ED, makes it reasonable to obtain a neurological consultation prior to considering obtaining an EEG. As of yet, there is no clear recommendation for ordering an EEG in the ED, and its use will be heavily dependent on local practice patterns and technical availability of personnel and equipment. The ACEP Clinical Policy only states that the EEG be “considered” for suspected NCSE and subtle SE, as well as in those patients who have received a long-acting paralytic or are in pharmacological coma.
New Anti-epileptic Drugs
A number of new AEDs have been added to the armamentarium available for managing seizures. In the majority of cases, the decision to use these medications should be made in conjunction with the physician who will assume care for the patient. The advantage of these drugs are that, in general, they have a better safety profile than the traditional AEDs, phenytoin, carbamazepine, Phenobarbital, ethosuximide, and valproic acid. The disadvantage is that they tend to be significantly more expensive. Table 7 lists some of the new AEDs; note that some are not protein bound and are renally excreted, making them preferred agents in patients who have liver disease and/or are on other drugs that are protein bound. Of the new AEDs, only levotiracetam has an intravenous formulation (not yet FDA approved) which may have benefit when rapid loading is required; however, there are no studies at this time supporting its use in status epilepticus.
The term alcohol related seizure refers to either seizure due to alcohol intoxication or its withdrawal. The diagnosis should be made only after work up for other causes of the seizure have been exhausted as this group of patients is more prone to traumatic abnormalities. A 1988 Denver study reported head CT results in 259 patients with a first alcohol-related convulsion. A “clinically significant” lesion was found in 16 (6.2%) patients, seven of whom were alert and had non-focal neurological exams and no history of trauma. Nearly 4% of patients had CT findings that changed clinical management (e.g., subdural hematoma, aneurysm, subarachnoid hemorrhage, and neurocysticercosis). In these patients, the history and physical examination did not predict the CT abnormality. This study emphasizes the importance of avoiding labeling an alcoholic with a first time seizure as having an alcohol withdrawal seizure; it also emphasizes that alcohol is a co-morbidity that drives the need for ED neuroimaging.212
Neuroimaging In Patients With Cocaine Related Seizures
There is one study that suggests that patients who experience a new onset cocaine-related generalized seizure do not require neuroimaging, as long as they do not have a severe headache, recover promptly, and have a normal postictal examination.213 This study only included 35 patients who had both a cocaine related seizure and a head CT and was not part of the formal derivation of a decision rule. In general, cocaine users are at a significantly increased risk of intracranial hemorrhage, as well as trauma and other risk factors; therefore, care must be applied when applying this evidence to clinical practice.
EEG In The ED
An EEG is used to help stratify patients regarding risk of seizure recurrence; thus, it is an important test in deciding who needs to be started on an AED. Inaddition, as discussed above, the EEG helps to identify those patients who are in nonconvulsive status epilepticus. The controversy is when and where an EEG needs to be done; the corollary is, what is the impact of delay in making an EEG based diagnosis? A survey of medical directors in accredited North American EEG laboratories revealed that a majority of facilities required neurologic consultation or other specialized consultation before emergent EEG could be obtained. Furthermore, though many labs claimed to provide “emergent” EEG, there was an average response time of approximately three hours from the time the test was requested, with a range up to 24 hours.214 A multicenter survey revealed that EEG was rarely performed in EDs.7
EEG interpretation is also a specialized field within the specialty of neurology, so it is reasonable to get an EEG only when there is someone available to interpretit. This, along with the generally limited availability of EEG in the ED, makes it reasonable to obtain a neurological consultation prior to considering obtaining an EEG. As of yet, there is no clear recommendation for ordering an EEG in the ED, and its use will be heavily dependent on local practice patterns and technical availability of personnel and equipment. The ACEP Clinical Policy only states that the EEG be “considered” for suspected NCSE and subtle SE, as well as in those patients who have received a long-acting paralytic or are in pharmacological coma.
New Anti-epileptic Drugs
A number of new AEDs have been added to the armamentarium available for managing seizures. In the majority of cases, the decision to use these medications should be made in conjunction with the physician who will assume care for the patient. The advantage of these drugs are that, in general, they have a better safety profile than the traditional AEDs, phenytoin, carbamazepine, Phenobarbital, ethosuximide, and valproic acid. The disadvantage is that they tend to be significantly more expensive. Table 7 lists some of the new AEDs; note that some are not protein bound and are renally excreted, making them preferred agents in patients who have liver disease and/or are on other drugs that are protein bound. Of the new AEDs, only levotiracetam has an intravenous formulation (not yet FDA approved) which may have benefit when rapid loading is required; however, there are no studies at this time supporting its use in status epilepticus.
Sign up for free access