Treatment Of Nonconvulsive Status Epilepticus Research Articles

34.: Non-convulsive status epilepticus in the elderly: A review

Altered mental state (AMS) is a common presentation in the elderly to the emergency department. It has been determined that about 16% of patients aged 60 or older with confusion of unknown origin had non-convulsive status epilepticus (NCSE). The diagnosis of NCSE is difficult in the elderly because possible etiologies of confusion could present with the same clinical picture. NCSE in the elderly carries major morbidity and mortality, attributable primarily to the etiology. Treatment of NCSE in the elderly is complex, involving treatment of the etiology and concomitant medical illnesses, whilst balancing the side effects and drug interactions of antiepileptic drugs. A review of the recent literature had been undertaken to look at the studies done on elderly patients with confusion of unknown origin or altered mental states that used an electroencephalogram (EEG) in the workup of these patients, and considered the differential diagnosis of NCSE. At this point, there are many unanswered questions. There needs to be a prospective study to determine the prevalence of NCSE specifically in the elderly patients who present with AMS consecutively. There probably is a need to look at the prevalence of NCSE due to specific etiologies in the elderly. There is a need to identify clinical features in these elderly patients which would predict NCSE with adequate sensitivity and specificity. There is also a need to develop management guidelines on timing, duration and cost effectiveness of emergency EEG in the context of investigating these elderly patients who present with AMS. In an ideal scenario, elderly patients with AMS could have an array of investigations done routinely in the emergency department without delay. NCSE could be picked up on the initial emergent EEG, and together with other neuro-imaging and biochemistry investigations, work out the etiology of the NCSE, and then decide on the appropriate treatment. The treatment plan could be analyzed for risk and benefits with the aid of a decision analysis tool.

Non-convulsive Status Epilepticus and Non-convulsive Seizures in Neurological ICU Patients

Non-convulsive seizures (NCS) or non-convulsive status epilepticus (NCSE) has been reported in 8-20 % of critically ill patient populations, and delayed diagnosis and treatment of NCSE may lead to increased mortality. This study seeks to better understand the risk factors, characteristics, and outcome of NCS/NCSE in the neurological ICU. This is a prospective observational study, recruiting consecutive patients admitted to the adult neurological ICU with altered mental status. Patients with anoxic brain injury were excluded from the study. Data were collected and analyzed for prevalence of NCSE/NCS, EEG patterns, associated risk factors, treatment response, and final outcome. NCSE/NCS was detected in 21 % of 170 subjects. Clinical seizures preceded EEG diagnosis of NCSE/NCS in 25 % of cases. Significant risk factors for NCSE/NCS were a past medical history of intracranial tumor, epilepsy, or meningitis/encephalitis, or MRI evidence of encephalomalacia. Subtle clinical findings such as twitching of oral or ocular muscles and eye deviations were found on exam in 50 % of the NCSE/NCS group. Mortality was increased in NCSE cases as 31 % of NCSE/NCS patients died compared to 14 % in non-NCSE/NCS group. Specific clinical features along with history and imaging findings may be used to identify patients at high risk of NCSE/NCS in the neurological ICU.

Use of continuous electroencephalography for diagnosis and monitoring of treatment of nonconvulsive status epilepticus in a cat

A 10-year-old domestic shorthair cat was evaluated because of presumed seizures. The cat had intermittent mydriasis, hyperthermia, and facial twitching. Findings of MRI and CSF sample analysis were unremarkable, and results of infectious disease testing were negative. Treatment was initiated with phenobarbital, zonisamide, and levetiracetam; however, the presumed seizure activity continued. Results of analysis of continuous electroencephalographic recording indicated the cat had nonconvulsive status epilepticus. The cat was treated with phenobarbital IV (6 mg/kg [2.7 mg/lb] q 30 min during a 9-hour period; total dose, 108 mg/kg [49.1 mg/lb]); treatment was stopped when a burst-suppression electroencephalographic pattern was detected. During this high-dose phenobarbital treatment period, an endotracheal tube was placed and the cat was monitored and received fluids, hetastarch, and dopamine IV. Continuous mechanical ventilation was not required. After treatment, the cat developed unclassified cardiomyopathy, azotemia, anemia, and pneumonia. These problems resolved during a 9-month period. Findings for the cat of this report indicated electroencephalographic evidence of nonconvulsive status epilepticus. Administration of a high total dose of phenobarbital and monitoring of treatment by use of electroencephalography were successful for resolution of the problem, and treatment sequelae resolved.

The Clinical Features and Prognosis of Patients With Nonconvulsive Status Epilepticus in the Neurological Intensive Care Unit of a Tertiary Referral Center in Turkey

The availability of video electroencephalography monitoring (VEEGM) in neurological intensive care units has allowed the recognition and treatment of nonconvulsive status epilepticus (NCSE). However, little is known about characteristics, management, and outcomes in patients with NCSE in developing countries. We retrospectively reviewed the video-EEG reports of 120 patients who were monitored from November 2009 to March 2013. Indications for video-EEG were mostly unexplained alterations of consciousness or witnessed convulsive seizures. We identified the clinical characteristics, treatment regimes, and outcomes of patients with NCSE and tried to determine which parameters were associated with prognosis. NCSE was detected in 12/120 (10%) patients (3 females, 9 males; age 24-86 years). Admission diagnoses were: stroke (3), epilepsy (3), autoimmune limbic encephalitis (3), herpes encephalitis (1), presumed encephalitis-cardiac arrest (1), and malignancy (1). Eight patients had witnessed convulsive seizures before video-EEG. Interictal periodic epileptiform discharges were detected in 9 patients. In one-third of patients, ≥2 EEG recordings were required to capture seizures. In addition to anticonvulsants, 3 patients received immunosuppressive therapy, while intravenous anesthetics were given to 7 patients. Four patients (33.3%; 1 female, 3 males; age 51-67 years; etiology: stroke, autoimmune encephalitis, encephalitis-cardiac arrest, and malignancy; Glasgow coma scale (GCS) score <8 in 3 patients; all had periodic discharges; intravenous anesthetics were used) died in the intensive care unit. NCSE is not an infrequent finding in neurological intensive care units, thus necessitating prolonged video-EEG monitoring in patients at risk. Witnessed convulsions may indicate the presence of nonconvulsive seizures in patients with altered consciousness. Repeated recordings may increase the detection of ictal events. Periodic epileptiform discharges are commonly observed and may predict poor prognosis. Mortality seems to be influenced mostly by the underlying etiology.

Calculating the risk benefit equation for aggressive treatment of non-convulsive status epilepticus.

To address the question: does non-convulsive status epilepticus warrant the same aggressive treatment as convulsive status epilepticus? We used a decision model to evaluate the risks and benefits of treating non-convulsive status epilepticus with intravenous anesthetics and ICU-level aggressive care. We investigated how the decision to use aggressive versus non-aggressive management for non-convulsive status epilepticus impacts expected patient outcome for four etiologies: absence epilepsy, discontinued antiepileptic drugs, intraparenchymal hemorrhage, and hypoxic ischemic encephalopathy. Each etiology was defined by distinct values for five key parameters: baseline mortality rate of the inciting etiology; efficacy of non-aggressive treatment in gaining control of seizures; the relative contribution of seizures to overall mortality; the degree of excess disability expected in the case of delayed seizure control; and the mortality risk of aggressive treatment. Non-aggressive treatment was favored for etiologies with low morbidity and mortality such as absence epilepsy and discontinued antiepileptic drugs. The risk of aggressive treatment was only warranted in etiologies where there was significant risk of seizure-induced neurologic damage. In the case of post-anoxic status epilepticus, expected outcomes were poor regardless of the treatment chosen. The favored strategy in each case was determined by strong interactions of all five model parameters. Determination of the optimal management approach to non-convulsive status epilepticus is complex and is ultimately determined by the inciting etiology.

Efficacy and safety of intravenous lacosamide in refractory nonconvulsive status epilepticus

Lacosamide (LCM) is a novel antiepileptic drug (AED) recently approved as an adjunctive therapy in the treatment of partial seizures in adults. LCM is available in oral and intravenous formulations, has linear pharmacokinetics and a unique mechanism of action. To evaluate the safety and efficacy of intravenous LCM in the treatment of nonconvulsive status epilepticus (NCSE) after failure of conventional therapy. We retrospectively reviewed all patients with NCSE treated with LCM. We reviewed the clinical and electrographic changes before and after LCM administration. We also noted any reported side effects including electrocardiographic changes. We report four cases of NCSE that were refractory to conventional treatment, but readily responsive to LCM. No side effects attributable to LCM were identified. Intravenous LCM may be safe and efficacious as an add-on AED for the treatment of NCSE when standard therapy fails.

Modified Atkins Diet for the Treatment of Nonconvulsive Status Epilepticus in Children

The authors describe the use of a modified Atkins diet for the treatment of 2 children with nonconvulsive status epilepticus. Patient 1 was a 4-year-and-11-month-old girl diagnosed with frontal lobe epilepsy. Since the age of 3 years and 10 months, she had daily nonconvulsive status epilepticus resistant to antiepileptic agents. Patient 2 was a 5-year-and-5-month-old girl with subcortical band heterotopia. She had nonconvulsive status epilepticus daily since the age of 5 years. They were treated with the modified Atkins diet, in which carbohydrate intake was restricted to 10 g/d without restriction on protein, caloric, or fluid intake. The nonconvulsive status epilepticus disappeared 5 and 10 days after the initiation of the diet treatment, respectively. They have been on the diet treatment and free from nonconvulsive status epilepticus for 19 and 4 months, respectively. The modified Atkins diet appears to be very effective for the treatment of nonconvulsive status epilepticus.

Intravenous lacosamide as successful treatment for nonconvulsive status epilepticus after failure of first-line therapy

Treatment of status epilepticus usually requires intravenous anticonvulsant therapy. Lacosamide is a novel anticonvulsant drug that is available as infusion solution. We describe a patient with nonconvulsive status epilepticus who was successfully treated with intravenous lacosamide.

Termination of absence status epilepticus by low‐dose intravenous levetiracetam

To the Editors: There is increasing data to support the efficacy and safety of levetiracetam (LEV) in the treatment of idiopathic generalized epilepsies (IGE) (Grünewald, 2005; Berkovic et al., 2007). However, the successful use of oral or intravenous (i.v.) LEV in patients with IGE presenting with absence status epilepticus (ASE) has not been reported to date. In a 37-year-old male, history and video-EEG disclosed IGE with the first manifestation of a generalized tonic-clonic seizure at the age of 27 years and frequent ASE with cognitive impairment of mild to moderate severity lasting up to several days. Previous antiepileptic medication included valproic acid, lamotrigine, topiramate, and zonisamide, but not LEV. After withdrawal of antiepileptic drugs during video-EEG monitoring, a habitual ASE occurred which was characterized by subtle but consistent attentional and executive disturbances as well as a cognitive slowing of fluctuating albeit gradually augmenting intensity. The patient was still responsive and showed good recollection of ictal events. The EEG displayed discontinuous generalized 3–5 Hz sharp-slow-wave-complexes. The number and the duration of these epileptiform potentials substantially increased in the course of the ASE. About 19 h after the clinical onset of ASE, neuropsychological examination by the Trail Making Test A and B (Reitan, 1992) revealed a marked reduction of cognitive speed and mental flexibility. Generalized epileptic activity was present in up to 60% of the time on surface EEG. The patient eventually stated that the subjective strain was no longer tolerable. We therefore administered 500 mg i.v. LEV within 5 min. After 20 min, additional 500 mg LEV was infused over 15 min. After the administration of the first 250 mg i.v. LEV, the patient reported a substantial relief; and after infusion of 500 mg LEV, he felt that he was back to his normal self. Repeated neuropsychological examination after i.v. administration of 500 and 1,000 mg LEV revealed a dose-dependent improvement in cognitive performance, which finally reached a normal level after application of 1,000 mg i.v. LEV (Fig. 1A and 1B). Accordingly, a ddose-dependent reduction down to baseline values of both the number of the generalized epileptiform potentials and the total of their duration was observed (Fig. 1C and 1D). The clinical and electrophysiological effects of i.v. LEV were sustained without any relapse during the following 6 h of observation. There were no adverse reactions. Dose-dependent and sustained effects of i.v. levetiracetam (LEV) on neuropsychological performance (A and B) and EEG (C and D). Onset, initiation of administration of i.v. LEV during absence status epilepticus; TMT, Trail Making Test, indicator of cognitive speed (TMT-A) and flexibility (TMT-B); ETP, generalized epileptiform potentials (mean values based on measurements of 5 min, besides 1 min measurement after administration of 250 mg i.v. LEV). ASE is a prolonged nonconvulsive state of ongoing or intermittent epileptic activity with cognitive or behavioral changes. Established therapeutic options include the i.v. administration of a benzodiazepine or valproic acid (Kaplan, 2005; Shorvon & Walker, 2005). However, sedation or respiratory depression is not uncommon after administration of benzodiazepines. In our patient with IGE, low-dose i.v. LEV led to an immediate and sustained interruption of a prolonged ASE without any undesired side effects. As reported in complex focal status epilepticus in focal epilepsies (Knake et al., 2008; Schulze-Bonhage et al., 2007), also in IGE the administration of i.v. LEV may be an effective and well-tolerated alternative to benzodiazepines in the treatment of nonconvulsive status epilepticus. Conflict of interest: We confirm that we have read the Journal's position on issues involved in ethical publication and affirm that this report is consistent with those guidelines. None of the authors has any conflict of interest to disclose.

How urgent is the treatment of nonconvulsive status epilepticus?

Status epilepticus may be classified for practical purposes into convulsive status epilepticus, which must be rapidly stopped to prevent death or neurologic sequelae, and nonconvulsive status epilepticus (NCSE), which is usually characterized by some degree of clouding of consciousness. This latter condition constitutes a diagnosis challenge, because it often goes unrecognized or is mistaken for behavioral or psychiatric disturbances. Emergency EEG is the key feature for diagnosis. NCSE are classically divided on the basis of the ictal EEG into absence status (AS), with predominantly symmetrical synchronous ictal discharges and complex partial status epilepticus (CPSE), with continuous or rapidly recurring complex partial seizures that may involve temporal and/or extratemporal regions (Shorvon, 1994). NCSE should obviously be rapidly treated because of the acute neurologic impairment of the patients, because of the attendant morbidity including physical injury, and because it may evolve on to generalized convulsions. There is reasonable concern about possible long-term effects, but longterm permanent neurologic damage from NCSE occurring in ambulatory patients has not yet been firmly documented as a mandate for aggressive treatment (Drislane, 1999). Despite its high recurrence rate, typical AS occurring in idiopathic generalized epilepsies almost always present a rapid and spectacular response to intravenous benzodiazepines. Anecdotal case reports in which AS lasted as long as weeks or even months recovered without any sequelae. Despite the lack of long-term follow-up studies, there is no scientific evidence that typical AS has any effect either on cognitive functions, or on the natural history of the underlying epileptic syndrome (Drislane, 1999). The influence of atypical AS on the cognitive prognosis in cryptogenic or symptomatic generalized epilepsies is not as clear. In most instances, AS does not appear to have any significant effect. This is, however, a subject of debate.

Levetiracetam in Nonconvulsive Status Epilepticus in Childhood: A Case Report

The authors report the case of a child with cerebral palsy and refractory epilepsy who developed nonconvulsive status epilepticus without acute medical cause treated successfully with levetiracetam. In accordance with other studies whose authors hypothesized that aggressive treatment may worsen the prognosis in elderly patients with nonconvulsive status epilepticus, the present authors successfully used a more conservative approach to the treatment of nonconvulsive status epilepticus in their patient. This case suggests that levetiracetam is a useful option for the treatment of nonconvulsive status epilepticus in childhood, in accordance with some authors who have described the anticonvulsant effects of levetiracetam in experimental status epilepticus and in status epilepticus in adults and in children with continuous spike waves during slow sleep.

Levetiracetam as a treatment option in non-convulsive status epilepticus

Non-convulsive status epilepticus (NCSE) is characterized by continuous or recurrent, generalized or focal epileptiform activity on the electroencephalogram and diverse clinical symptoms with alterations of mental state and vigilance. NCSE is not rare but certainly under diagnosed. There is some debate about how aggressive NCSE should be treated, as high dose anticonvulsants maybe partially responsible for the morbidity and mortality of patients with NCSE. We hypothesized that levetiracetam (LEV) as a well tolerated, highly effective new anticonvulsant, may be a safe treatment option. We retrospectively analyzed all (8) patients with NCSE who received levetiracetam from our database, compared with 11 patients with NCSE treated with conventional intravenous status medication as controls. These eight patients showed a marked clinical improvement with final cessation of ictal EEG-activity and clinical symptoms of NCSE after initiation of LEV within 3 days (mean 1.5 days). The response to conventional treatment was similarly effective but there were severe side effects whereas no relevant side effects in the LEV-treated group were noticed. A long-term follow up (6-36 months from discharge) revealed six patients with a persisting reduction in seizure frequency on medication with LEV. One patient changed the anticonvulsive medication because of inefficacy and one died from other causes than epilepsy 2 months after discharge from hospital. We found no significant differences in hospitalisation time, time in intensive care unit and outcome between the LEV group and the control group. This retrospectively acquired data suggests that LEV may be a well tolerated, effective treatment option in NCSE. This highlights the need for a prospective controlled study to further elucidate the utility of LEV in the treatment of NCSE, particularly as an intravenous formulation is now available.

Role of valproate across the ages. Treatment of epilepsy in children

In June 2005 a team of experts participated in a workshop with the objective of reaching agreement on the place of valproate use in the treatment of paediatric epilepsy patients. A general "consensus of the meeting" was that the initiation of antiepileptic drug (AED) treatment should be based on a seizure-syndromic approach in children. Participants of the meeting also agreed that valproate is currently the AED with the broadest spectrum across all types of seizures and syndromes. Its superiority has been shown over almost 40 years of clinical experience. The best results are seen in idiopathic generalized epilepsy with or without photosensitivity, idiopathic focal and symptomatic generalized tonic-clonic seizures (GTCS). Evidence supports the use of valproate, ethosuximide and lamotrigine in absence epilepsies and the use of carbamazepine, lamotrigine, oxcarbazepine, phenytoin, topiramate, valproate and phenobarbital for primary GTCS. For new AEDs trials have been undertaken to define their therapeutic role but studies comparing their role to 'old' broad-spectrum drugs in specific syndromes are missing. Experts concluded that intravenous (i.v.) valproate is a useful agent in the treatment of non-convulsive status epilepticus (SE). There is an easy transition to oral treatment following i.v. valproate use. The discussion also concluded that, despite the lack of studies, valproate is an interesting, underutilized alternative in convulsive SE but more controlled studies are needed. The side effects of valproate use are well documented. Its effect on cognition and behaviour is more favourable than many of the other AEDs which is an important consideration in children. Overall, the clinical consensus of the meeting was that valproate's well established therapeutic properties far outweigh the negative side effects. Contraindication or withdrawal should be assessed individually.

Ellen R. Grass Lecture: Rapid EEG Analysis for Intensive Care Decisions in Status Epilepticus

ABSTRACT.Nonconvulsive status epilepticus in intensive care units (ICUs) is common and increases the risk of death. Nonconvulsive status epilepticus treatment delays are associated with poor patient outcomes. Continuous EEG or EEG-video monitoring is used in ICU settings to diagnose subtle seizures and nonconvulsive status epilepticus among at-risk populations including patients with closed head injuries and altered consciousness, stroke, subarachnoid hemorrhage, neonates at-risk for sepsis or hypoxic-ischemic encephalopathy, and children who have undergone surgery for congenital heart disease. However expert EEG interpretation, currently required for accurate diagnosis, often lags behind the real-time recordings by hours or even longer. At most hospitals the numbers of at-risk patients in intensive care units far exceeds the capacity of the available EEG equipment and personnel to perform and interpret EEGs. Seizure-detection software, compressed EEG spectral arrays, and near real-time remote EEG interpretation have brought us closer to the goal of real-time analysis of EEG for intensive care decisions, but even at major tertiary referral centers the vast majority of at-risk ICU patients do not undergo EEG monitoring. Additional technological advances, innovative use of EEG technologists and ICU personnel, and clinical trials of new EEG monitoring technology and associated clinical outcomes are needed to achieve the goal of optimal use of EEG data for intensive care decisions.

Nonconvulsive status epilepticus: Epilepsy Research Foundation Workshop Reports

In April 2004, a group of physicians with an interest in nonconvulsive status epilepticus representing a spectrum of opinion met in Oxford, sponsored by the Epilepsy Research Foundation (a charitable organization), to discuss and debate the definition, diagnosis and treatment of nonconvulsive status epilepticus. We felt that such a meeting would be useful, as nonconvulsive status epilepticus is a subject that provokes strong reactions, perhaps largely due to the relative lack of evidence and the surfeit of opinion. The meeting was arranged such that there were formal talks followed by a discussion led by one of the attendees. We present here the extended abstracts of the main talks with the points raised by the discussants. Despite disagreements on certain issues there was much in the way of consensus. First, it was agreed that nonconvulsive status epilepticus is a term that covers a range of disparate conditions with varying prognoses and treatments. The agreed definition was thus suitably vague, «Nonconvulsive status epilepticus is a term used to denote a range of conditions in which electrographic seizure activity is prolonged and results in nonconvulsive clinical symptoms». Secondly, it was agreed that even within a specific condition ( e.g. complex partial status epilepticus), the prognosis and treatment depends upon the context in which the condition occurs ( e.g. in the critically ill, in coma, in the «walking wounded» and in people with prior epilepsy). Perhaps, most importantly it was agreed that we lacked good clinical data, and the challenge was to design good studies for a condition that is underrecognised and often difficult to diagnose.

Diagnosis and Treatment of Nonconvulsive Status Epilepticus in an Intensive Care Unit Setting.

Nonconvulsive status epilepticus (NCSE) in adults is a heterogeneous epileptic emergency and includes absence status (AS), complex-partial status epilepticus (CPSE), and the status epilepticus of epileptic encephalopathy (SEEE). The latter seems to be strikingly frequent among patients in intensive care units (ICU). Diagnosis of NCSE is difficult, but has to be made quickly. It relies on clinical signs and a confirmation electroencephalography (EEG). According to the different etiologies and outcomes of AS, CPSE, and SEEE, treatment has to be individually adapted, but needs to follow some basic principles--treatment should take place in the ICU and be monitored by continuous EEG. With a few exceptions, the first drug is an intravenous benzodiazepine, mainly lorazepam. Intravenous fosphenytoin or phenytoin or valproate may follow next. If some forms of NCSE are resistant to first- and second-line treatments, single or combinations of anesthetics and enteral antiepileptic drugs (AEDs) may be added. This opinion is not evidence-based, and randomized controlled prospective trials to evaluate optimal treatment of NCSE are of first priority.

Nonconvulsive status epilepticus with frontal features: quantitating severity of subclinical epileptiform discharges provides a marker for treatment efficacy, recurrence and outcome

Nonconvulsive status epilepticus (NCSE) is difficult to diagnose but is an important cause of cognitive impairment. Electroencephalogram (EEG) monitoring is required for diagnosis and treatment. Little is known regarding the stability of subclinical epileptiform discharges (SEDs) preceding NCSE nor what strategies may optimize patient outcomes. We report extended follow-up of patients with recurrent frontal SEDs, integrating EEG and cognitive findings before and following treatment of NCSE, and show that quantitating SED severity provides an objective marker of treatment efficacy and recurrence.

Diagnosis and treatment of nonconvulsive status epilepticus.

Nonconvulsive status epilepticus (SE) is not uncommon and comprises at least one-third of all cases of SE. However, nonconvulsive SE consists of very different syndromes, a common feature being the difficulty in making the diagnosis. In this review, nonconvulsive SE is divided into typical absence SE, complex partial SE, nonconvulsive SE in patients with learning difficulties (including electrical SE during sleep, atypical absence SE and tonic SE), and nonconvulsive SE in coma. These conditions have different prognoses and treatments. The diagnosis of these conditions is critically dependent on EEG. When the EEG demonstrates typical ictal patterns, the diagnosis is usually straightforward. However, in many circumstances the EEG has to be differentiated from encephalopathic patterns, and this differentiation can prove troublesome, although the clinical and electrographic response to treatment can prove helpful. Nonconvulsive SE in patients with learning difficulties possibly provides the greatest diagnostic difficulty; the clinical presentation can be subtle resulting in the diagnosis being frequently missed. Whether the neuronal damage that occurs in convulsive SE and in animal models of limbic SE also occurs in nonconvulsive SE in humans is still a matter of debate. There are critical differences between the animal models and the human condition. Indeed, the prognosis of nonconvulsive SE is usually dependent on the underlying aetiology rather than the persistence of electrographic discharges. Because of these doubts, a more conservative approach to the treatment of particular types of nonconvulsive SE (those with a better prognosis) has been taken in this article. Thus, in most instances, oral benzodiazepines for the treatment of typical absence SE and complex partial SE are recommended. In some circumstances intravenous medication is necessary, but in neither condition is anaesthetic coma recommended. This contrasts with nonconvulsive SE in coma in which a more aggressive approach is suggested. Until there are more relevant animal models, and controlled trials of conservative versus more aggressive treatment, treatment regimens for nonconvulsive SE will remain largely speculative.

Epidemiology and evidence for morbidity of nonconvulsive status epilepticus.

Convulsive status epilepticus (SE) is convincingly related to serious morbidity and mortality and well recognized as a medical emergency, but prompt diagnosis and treatment of patients with nonconvulsive status epilepticus (NCSE) is often not emphasized because its consequences are thought to be benign. Nonconvulsive status epilepticus has been considered a relatively benign entity because it does not produce the adverse systemic consequences of convulsive status epilepticus, such as hyperthermia, acidosis, hyperkalemia, pulmonary compromise, or cardiovascular collapse. However, recent reports indicate that NCSE is not so benign. There are two major forms of NCSE, absence status epilepticus and complex partial status epilepticus. Typical absence status epilepticus does not appear to have very serious consequences and may be a type of "inhibitory" seizure, but complex partial status epilepticus has been associated with serious morbidity and mortality. Despite not causing the systemic physiologic or metabolic derangements seen with convulsive SE, complex partial status epilepticus is still associated with the two other major factors correlated with poor outcomes in convulsive SE: 1) neuronal damage from abnormal electrical activity and 2) the interaction of acute neurologic disorders, such as stroke, that may precipitate SE. Other similar epileptiform encephalopathies such as "subclinical," "electroencephalographic," "nontonic-clonic," and "subtle" SE have not been as well studied as NCSE but pose similar issues. Early diagnosis and aggressive intervention have proven the best means of averting adverse outcomes in patients with convulsive SE. The diagnosis and treatment of NCSE, particularly complex partial status epilepticus, merit similar emphasis and attention.

Quantitative EEG-measurements in chronic alcoholics — spectral parameters of the topographic EEG in the course of withdrawal therapy

Non-convulsive status epilepticus (NCSE) is characterized by continuous or recurrent, generalized or focal epileptiform activity on the electroencephalogram and diverse clinical symptoms with alterations of mental state and vigilance. NCSE is not rare but certainly under diagnosed. There is some debate about how aggressive NCSE should be treated, as high dose anticonvulsants maybe partially responsible for the morbidity and mortality of patients with NCSE. We hypothesized that levetiracetam (LEV) as a well tolerated, highly effective new anticonvulsant, may be a safe treatment option. We retrospectively analyzed all (8) patients with NCSE who received levetiracetam from our database, compared with 11 patients with NCSE treated with conventional intravenous status medication as controls. These eight patients showed a marked clinical improvement with final cessation of ictal EEG-activity and clinical symptoms of NCSE after initiation of LEV within 3 days (mean 1.5 days). The response to conventional treatment was similarly effective but there were severe side effects whereas no relevant side effects in the LEV-treated group were noticed. A long-term follow up (6–36 months from discharge) revealed six patients with a persisting reduction in seizure frequency on medication with LEV. One patient changed the anticonvulsive medication because of inefficacy and one died from other causes than epilepsy 2 months after discharge from hospital. We found no significant differences in hospitalisation time, time in intensive care unit and outcome between the LEV group and the control group. This retrospectively acquired data suggests that LEV may be a well tolerated, effective treatment option in NCSE. This highlights the need for a prospective controlled study to further elucidate the utility of LEV in the treatment of NCSE, particularly as an intravenous formulation is now available.