Second-line status epilepticus treatment: comparison of phenytoin, valproate, and levetiracetam

Levetiracetam use in the critical care setting

Intravenous (IV) levetiracetam (LEV) is currently approved as an alternative or replacement therapy for patients unable to take the oral form of this antiepileptic drug (AED). The oral form has Food and Drug Administration (FDA) indications for adjunctive therapy in the treatment of partial onset epilepsy ages 1 month or more, myoclonic seizures associated with juvenile myoclonic epilepsy starting with the age of 12 and primary generalized tonic-clonic seizures in people 6 years and older. Since the initial introduction, oral and IV LEV has been evaluated in various studies conducted in the critical care setting for the treatment of status epilepticus, stroke-related seizures, seizures following subarachnoid or intracerebral hemorrhage, post-traumatic seizures, tumor-related seizures, and seizures in critically ill patients. Additionally, studies evaluating rapid infusion of IV LEV and therapeutic monitoring of serum LEV levels in different patient populations have been performed. In this review we present the current state of knowledge on LEV use in the critical care setting focusing on the IV uses and discuss future research needs.

Status epilepticus

PURPOSE OF REVIEW

This review presents the state of the art in the diagnosis and management of status epilepticus.

RECENT FINDINGS

In addition to general background, this article presents the most recent findings regarding the diagnosis and treatment of status epilepticus, including the results of the Rapid Anticonvulsant Medication Prior to Arrival Trial (RAMPART) and the available data on the use of newer antiepileptic and anesthetic drugs in the treatment of refractory status epilepticus. It also presents available guidelines such as those from the Neurocritical Care Society.

SUMMARY

Despite recent advances, the management of status epilepticus remains a challenge. Rapid treatment, a written treatment protocol, early consideration of nonconvulsive seizures, and avoiding overtreatment and medical complications are the keys to successful management. This article summarizes the current evidence and guidelines.

Seizures and the neurosurgical intensive care unit

The cause of seizures in the neurosurgical intensive care unit (NICU) can be categorized as emanating from either a primary brain pathology or from physiologic derangements of critical care illness. Patients are typically treated with parenteral antiepileptic drugs. For early onset ICU seizures that are easily controlled, data support limited treatment. Late seizures have a more ominous risk for subsequent epilepsy and should be treated for extended periods of time or indefinitely. This review ends by examining the treatment algorithms for simple seizures and status epilepticus and the role newer antiepileptic use can play in the NICU.

Guidelines for the evaluation and management of status epilepticus

Status epilepticus (SE) treatment strategies vary substantially from one institution to another due to the lack of data to support one treatment over another. To provide guidance for the acute treatment of SE in critically ill patients, the Neurocritical Care Society organized a writing committee to evaluate the literature and develop an evidence-based and expert consensus practice guideline. Literature searches were conducted using PubMed and studies meeting the criteria established by the writing committee were evaluated. Recommendations were developed based on the literature using standardized assessment methods from the American Heart Association and Grading of Recommendations Assessment, Development, and Evaluation systems, as well as expert opinion when sufficient data were lacking.

Efficacy of intravenous lacosamide as an add-on treatment in refractory status epilepticus: a multicentric prospective study

OBJECTIVE

Treatment of status epilepticus (SE) has not changed in the last few decades, benzodiazepines plus phenytoin or valproate being the most common treatment. Once this first and second line treatment has failed SE is considered refractory (RSE). This study aimed to assess the efficacy and tolerability of intravenous (iv) lacosamide (LCM) in RSE.

METHOD

Patients with RSE who were treated with ivLCM in six Spanish centers were prospectively included. Efficacy was defined as cessation of seizures after starting ivLCM, with no need for any further antiepileptic drug. All patients had been unsuccessfully treated following the standard protocol (benzodiazepines plus phenytoin or valproate) before ivLCM was added.

RESULTS

Thirty-four patients were included, 52.9% men, with mean age of 60.15 years. In 58.9% of patients the etiology was symptomatic, and the most common type of SE was focal convulsive (82.4%). Mean initial bolus dose of LCM was 323.53mg. ivLCM was effective in more than half of patients (64.7%), with termination of SE before 12h in 50% of them. ivLCM was used as a fourth or later option in 76.5% of patients. No serious adverse events attributable to LCM were reported.

CONCLUSIONS

LCM might be a fast, effective and safe add-on treatment in RSE.

Status epilepticus and the use of continuous EEG monitoring in the intensive care unit

PURPOSE OF REVIEW

Status epilepticus (SE) is one of the major neurologic emergencies. Newer data about the genesis and treatment of this condition are available to help improve our understanding and management.

RECENT FINDINGS

Approximately 150,000 cases of generalized convulsive SE occur in the United States each year. Clinically apparent seizures complicate about 8% of intensive care unit admissions, and another 10% of ICU patients suffer electrographic seizures in the course of another critical illness. Some of these cases result from previously under-recognized epileptogenic effects of commonly used drugs, such as cefepime. Continuous EEG (cEEG) recording is necessary for both diagnosis and management in these patients, especially since anticonvulsant drugs may abolish motor activity without stopping seizures. Recent studies have underscored the utility of benzodiazepines as the first-line agents for SE termination. The recently published Rapid Anticonvulsant Medication Prior to Arrival Trial (RAMPART) demonstrates that the more rapidly treatment is administered, the more effective it will be. When SE fails to respond to usual doses of benzodiazepines, it should be considered refractory to conventional anticonvulsants, and a general anesthetic approach is likely to be necessary.

SUMMARY

While definitions have varied, patients should be managed for SE after 5 minutes of seizure activity. Management of a patient with SE involves three phases: termination of SE, prevention of recurrence, and treatment of complications. The typical anticonvulsants have limited ability to terminate SE; lorazepam is the most useful, controlling SE in 65% of patients experiencing generalized convulsive SE. If the first conventional anticonvulsant fails, others are unlikely to be useful, and one of the newer anticonvulsants or a general anesthetic agent should be considered. EEG is crucial in the diagnosis and classification of potential seizures. cEEG monitoring helps to guide anticonvulsant therapy in patients with SE and those with frequent seizures. In addition, cEEG has the potential for presymptomatic diagnosis of delayed neurologic deterioration in patients with subarachnoid hemorrhage and for the differential diagnosis of stroke subtypes, especially when cEEG is subjected to signal processing.

[Status epilepticus]

Status epilepticus (SE) is a medical emergency. For diagnostic purposes EEG is mandatory when motor phenomena are absent or when a single seizure evolves into SE with impaired consciousness. The EEG may show focal or generalized status patterns, which must be distinguished from encephalopathies. Initially benzodiazepines are recommended; lorazepam is the drug of choice. When the SE persists, phenytoin, valproate, levetiracetam, lacosamide, and phenobarbital are administered. The choice depends on the underlying comorbidities. In this phase, only phenytoin is licensed. A generalized tonic-clonic status which is refractory is then treated with anesthetics including midazolam, disoprivan, or thiopental. The goal is to achieve burst suppression in the EEG and coadministration of antiepileptic drugs.

Newer antiepileptic drugs in the treatment of status epilepticus: impact on prognosis

Newer antiepileptic drugs (AEDs) are increasingly prescribed and seem to have a comparable efficacy as the classical AEDs; however, their impact on status epilepticus (SE) prognosis has received little attention. In our prospective SE database (2006-2010), we assessed the use of older versus newer AEDs (levetiracetam, pregabalin, topiramate, lacosamide) over time and its relationship to outcome (return to clinical baseline conditions, new handicap, or death). Newer AEDs were used more often toward the end of the study period (42% of episodes versus 30%). After adjustment for SE etiology, SE severity score, and number of compounds needed to terminate SE, newer AEDs were independently related to a reduced likelihood of return to baseline (p<0.001) but not to increased mortality. These findings seem in line with recent findings on refractory epilepsy. Also, in view of the higher price of the newer AEDs, well-designed, prospective assessments analyzing the impact of newer AEDs on efficacy and tolerability in patients with SE appear mandatory.

Assessment of risk factors for early seizures following surgery for meningiomas using logistic regression analysis

This study analysed the influence of clinical factors on early postoperative seizures in patients with meningiomas and constructed a logistic regression equation for assessing risk factors. Clinical data from 222 patients with meningiomas were collected. The odds ratios (ORs) for independent variables were determined: the ORs for preoperative seizure history and movement disorder were > 1, whereas the OR for prophylactic therapy was < 1. A logistic regression analysis was then performed to select potential risk factors for early postoperative seizures. Five variables (preoperative seizure history, movement disorder, tumour location, primary location of initial tumour and prophylactic therapy) were introduced into the regression model. A logistic regression equation was then constructed that had a positive predictive value of 66.65% and a negative predictive value of 84.95%. This suggested that the five variables introduced in the equation were closely associated with early postoperative seizures, with preoperative seizure history and movement disorder as potential risk factors and prophylactic therapy as a protective factor.

Anaesthesia and epilepsy

Epilepsy is the most common serious neurological disorder, with a prevalence of 0.5-1% of the population. While the traditional antiepileptic drugs (AEDs) still play a significant role in treatment of seizures, there has been an influx of newer agents over the last 20 yr, which are now in common usage. Anaesthetists are frequently faced with patients with epilepsy undergoing emergency or elective surgery and patients suffering seizures and status epilepticus in the intensive care unit (ICU). This review examines perioperative epilepsy management, the mode of action of AEDs and their interaction with anaesthetic agents, potential adverse effects of anaesthetic agents, and the acute management of seizures and refractory status epilepticus on the ICU. Relevant literature was identified by a Pubmed search of epilepsy and status epilepticus in conjunction with individual anaesthetic agents.

Treatment of status epilepticus in a large community hospital

BACKGROUND

Status epilepticus (SE) is a neurological emergency usually requiring immediate medical treatment. Due to the lack of adequate studies, treatment guidelines and their application vary between countries and institutions. We intended to analyze current treatment of SE in a German community hospital.

METHODS

We retrospectively identified patients from a large community hospital in northern Germany who had been diagnosed with SE between August 2008 and December 2010. Their charts were reviewed regarding sociodemographic variables, treatment and outcome.

RESULTS

We studied the first SE episode in 172 patients with a median age of 69 years (range 18-90 years). The etiology was acute symptomatic in 30 patients, progressive symptomatic in 22 patients and remote symptomatic in 120 patients. Presentation was generalized convulsive in 60 patients, non-convulsive in 72 patients and simple motor/aura in 40 patients. Median latency from onset to treatment start was 0.75 h (range 0.2-336 h). Initial treatment had a success rate (SR) of 40%. Second line treatment had a success rate of 54%. In patients whose seizures were refractory to the first two drugs, success rates were between 31% and 55%, with only a minority of the patients receiving established drugs such as phenytoin or barbiturates. Multivariate analysis revealed non-convulsive semiology as the only factor significantly associated with refractoriness. SE could be terminated in 95% of the patients and in-hospital mortality was 10%. Benzodiazepines and phenytoin had the most severe side effects.

CONCLUSIONS

Status epilepticus can be terminated successfully and with low in-hospital mortality in the vast majority of the patients treated in a large community hospital. The success rate of each treatment step is between 30% and 55% regardless of the substances used.

A systematic review of randomized controlled trials on the theraputic effect of intravenous sodium valproate in status epilepticus

We performed this systematic review to determine whether intravenous sodium valproate was more effective or safer than other drugs in patients with status epilepticus (SE). A literature search was performed using Medline, Embase, and the Cochrane Central Register of Controlled Trials (CENTRAL). From 544 articles screened, 5 were identified as randomized controlled trials and were included for data extraction. The main outcomes were SE controlled and risk of seizure continuation. The meta-analysis was performed with the Random-effect model. The quality of the included studies was evaluated by GRADE (Grading of Recommendations Assessment, Development, and Evaluation). There was no significant statistics in SE controlled between intravenous sodium valproate and phenytoin. Compared with diazepam, sodium valproate had a statistically significant lower risk of time interval for control of refractory SE (RSE) after having drugs; however, there was no statistically significant difference in SE controlled within 30 min between the two groups. There was no statistically significant difference in cessation from status between intravenous sodium valproate and levetiracetam. Intravenous sodium valprate was as effective as intravenous phenytoin for SE controlled and risk of seizure continuation.

Management of refractory status epilepticus in adults: still more questions than answers

Refractory status epilepticus (RSE) is defined as status epilepticus that continues despite treatment with benzodiazepines and one antiepileptic drug. RSE should be treated promptly to prevent morbidity and mortality; however, scarce evidence is available to support the choice of specific treatments. Major independent outcome predictors are age (not modifiable) and cause (which should be actively targeted). Recent recommendations for adults suggest that the aggressiveness of treatment for RSE should be tailored to the clinical situation. To minimise intensive care unit-related complications, focal RSE without impairment of consciousness might initially be approached conservatively; conversely, early induction of pharmacological coma is advisable in generalised convulsive forms of the disorder. At this stage, midazolam, propofol, or barbiturates are the most commonly used drugs. Several other treatments, such as additional anaesthetics, other antiepileptic or immunomodulatory compounds, or non-pharmacological approaches (eg, electroconvulsive treatment or hypothermia), have been used in protracted RSE. Treatment lasting weeks or months can sometimes result in a good outcome, as in selected patients after encephalitis or autoimmune disorders. Well designed prospective studies of RSE are urgently needed.