Status epilepticus. Causes, clinical features and consequences in 98 patients

Midazolam versus diazepam for the treatment of status epilepticus in children and young adults: a meta-analysis

BACKGROUND

Rapid treatment of status epilepticus (SE) is associated with better outcomes. Diazepam and midazolam are commonly used, but the optimal agent and administration route is unclear.

OBJECTIVES

The objective was to determine by systematic review if nonintravenous (non-IV) midazolam is as effective as diazepam, by any route, in terminating SE seizures in children and adults. Time to seizure cessation and respiratory complications was examined.

METHODS

We performed a search of PubMed, Web of Knowledge, Embase, Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, American College of Physicians Journal Club, Cochrane Central Register of Controlled Trials, the Cumulative Index to Nursing and Allied Health Literature, and International Pharmaceutical Abstracts for studies published January 1, 1950, through July 4, 2009. English language quasi-experimental or randomized controlled trials comparing midazolam and diazepam as first-line treatment for SE, and meeting the Consolidated Standards of Reporting Trials (CONSORT)-based quality measures, were eligible. Two reviewers independently screened studies for inclusion and extracted outcomes data. Administration routes were stratified as non-IV (buccal, intranasal, intramuscular, rectal) or IV. Fixed-effects models generated pooled statistics.

RESULTS

Six studies with 774 subjects were included. For seizure cessation, midazolam, by any route, was superior to diazepam, by any route (relative risk [RR] = 1.52; 95% confidence interval [CI] = 1.27 to 1.82). Non-IV midazolam is as effective as IV diazepam (RR = 0.79; 95% CI = 0.19 to 3.36), and buccal midazolam is superior to rectal diazepam in achieving seizure control (RR = 1.54; 95% CI = 1.29 to 1.85). Midazolam was administered faster than diazepam (mean difference = 2.46 minutes; 95% CI = 1.52 to 3.39 minutes) and had similar times between drug administration and seizure cessation. Respiratory complications requiring intervention were similar, regardless of administration route (RR = 1.49; 95% CI = 0.25 to 8.72).

CONCLUSIONS

Non-IV midazolam, compared to non-IV or IV diazepam, is safe and effective in treating SE. Comparison to lorazepam, evaluation in adults, and prospective confirmation of safety and efficacy is needed.

A clinical, radiological and outcome study of status epilepticus from India

The objective of this study is to evaluate the clinical and radiological characteristics and the outcome of status epilepticus (SE). 117 consecutive patients with SE were evaluated including their demographics, history of epilepsy, antiepileptic drug (AED) default, comorbidities, SE type and duration. The study included 22 children, 77 adults and 18 elderly patients with SE. Blood counts, serum chemistry, ECG, cranial MRI, cerebrospinal fluid and EEG were done. Patients were treated with IV phenytoin, valproate, lorazepam or diazepam as per a fixed protocol and responses to first and second drugs were noted. Death during hospital was recorded. The etiology of SE was infection in 53.8%, drug default in 7.9%, metabolic in 14.5%, stroke in 12.8% and miscellaneous in 11% of patients. 92.3% of patients had convulsive and 7.7% nonconvulsive SE. Cranial MRI was abnormal in 62%. Infection as an etiology was more common in children, drug default and metabolic causes in adults and stroke in adults and elderly. Following first AED, SE was controlled in 50%. 30% of patients remained refractory to second AED which was related to duration of SE and mortality. 29% patients died and death was higher in elderly (44%) compared to children (14%). Acute symptomatic SE is more common in developing countries. Refractory SE is associated with SE duration and mortality.

Status epilepticus

Status epilepticus (SE) still results in significant mortality and morbidity. Whereas mortality depends mainly on the age of the patient as well as etiology, morbidity often results from a myriad of complications that occur during prolonged admission to an intensive care environment. Although SE is a clinical diagnosis in most cases (convulsant), its treatment requires support by continuous electroencephalographic recording to ensure cessation of potential nonconvulsive elements of SE. Treatment must be initiated as early as possible and consists of benzodiazepine administration and supportive measures for the airway and circulation. These initial interventions are followed by effective intravenous antiepileptic drugs. If the SE becomes refractory, more complex intensive care interventions, such as induction of barbiturate coma, need to be pursued. Data regarding the role of more recently available antiepileptic drugs in treating SE also are discussed in this review.

Free phenytoin concentration measurement in brain extracellular fluid: a pilot study

This article investigates the relationship between brain extracellular fluid free phenytoin concentration and plasma free phenytoin concentration in adults with acute brain injury. Daily cerebral microdialysate free phenytoin concentration was measured in eight adults with acute brain injury and compared with simultaneous measurement of plasma free phenytoin concentration. The group data revealed no significant correlation between microdialysate and plasma free phenytoin concentration (r = 0.34, p = 0.41). However, in two patients, with a sufficient number of samples for intra-individual analysis, there was a significant correlation between microdialysate and plasma free phenytoin concentration (r = 0.92, p < 0.001 and r = 0.88, p < 0.01). In vitro microdialysis relative recovery for phenytoin was 2.1%. In the context of acute brain injury, measurement of free plasma phenytoin concentration may not provide an accurate reflection of regional brain extracellular fluid free phenytoin concentration and may have limitations with respect to achieving reproducible brain extracellular fluid free phenytoin concentrations. This has implications for dosing regimens relying on plasma phenytoin levels.

Long-term survival in patients with status epilepticus: a tertiary referral center study

PURPOSE

To determine long-term survival in patients with status epilepticus (SE).

METHODS

We prospectively followed patients admitted for the first (69.6%) or recursive episode of SE between January 1, 1989 and December 31, 1997 at the Institute of Neurology, Belgrade, Serbia, until death or study termination (December 31, 2006). Data were obtained for cause of death; etiology of SE-acute symptomatic (AS), progressive symptomatic (PS), remote symptomatic (RS), and idiopathic/cryptogenic (I/C); presence of epilepsy; and reoccurrence of SE. Standardized mortality rate (SMR), survival, and regression analysis were used.

RESULTS

A total of 120 of 750 patients with an episode of SE (15.9%) died in the 30-day period following SE. Data for 207 of 630 (32.8%) surviving patients (35.7% with initial SE) were available at the end of follow-up [median 12 years; 95% confidence interval (CI) 11.1-12.8]. SMR was significantly increased (SMR = 1.81; 95% CI 1.32-2.41). There were 46 deaths (22.2%): 15 of 65 in the AS, 20 of 29 in the PS, 6 of 29 in the RS, and 5 of 75 in the I/C groups. Five-year survival rate was lowest in the PS (45%) compared to AS (91%), RS (87%), and I/C (99%) groups. The following characteristics increased long-term risk for mortality: older age [Exp(B) 1.05, 95% CI 1.029-1.072], PS and AS etiology [Exp(B) 15.6, 95% CI 5.8-41.6; 3.3, 95% CI 1.2-9.1], presence of epilepsy [Exp(B) 2.3, 95% CI 1.2-4.3], and initial SE [Exp(B) 2.4, 95% CI 1.4-4.4].

DISCUSSION

Approximately one of five patients die within 12 years after an episode of SE. Symptomatic SE (PS and AS), initial SE, age, and presence of epilepsy are associated with long-term increased risk of death.

Intravenous levetiracetam as treatment for status epilepticus

There are established drugs for the treatment of status epilepticus (SE) but their potentially hazardous side-effects are well known. Levetiracetam (LEV) is a novel anticonvulsant available for intravenous (i.v.) application. It could be an alternative when standard drugs fail or should be avoided. We retrospectively identified patients from two German teaching hospitals who were treated with LEV i.v. for SE. Their charts were reviewed regarding sociodemographic data, type, etiology, onset and duration of SE, dose of LEV, concurrent antiepileptic drugs (AED) treatment, tolerability, and outcome. Thirty-two patients (15 female) were found who were treated with i.v. LEV for SE (median age 71 years). Two patients were exclusively treated with LEV. Eight received a low and further 20 patients a high dose of benzodiazepines before LEV. Two patients were treated with LEV to enable discontinuation of narcosis. SE was generalized convulsive in five, nonconvulsive in 20, and simple focal in seven patients. Etiology was acute 13 times and remote symptomatic 16 times; three SE were of unknown etiology. Therapy was initiated within a median time of 3 h and LEV i.v. was applied within a median time of 6 h. Median LEV bolus was 2,000 mg; median total dose on day 1 was 3,500 mg. Benzodiazepines plus i.v. LEV terminated SE in 23 patients without application of additional anticonvulsants, 10 within 30 min. LEV could not terminate SE in seven patients. We documented nausea and emesis in one and elevation of liver enzymes in another patient that were likely to be attributed to LEV. LEV i.v. seems to be safe with relevant efficiency for the treatment of SE in elderly and multimorbid patients when comorbidity and respiratory insufficiency precludes high doses of benzodiazepines or phenytoin.

Comparisons of the mortality and clinical presentations of status epilepticus in private practice community and university hospital settings in Richmond, Virginia

We prospectively compared the clinical course of 119 patients treated for status epilepticus (SE) in private practice community hospitals and 344 SE patients treated in the VCU university hospitals in Richmond, Virginia USA over a 2-year period to test the hypothesis that SE presents with the same mortality and clinical patterns in both clinical settings. Of the patients reviewed, the major etiologies for SE were cerebrovascular disease, decreased anti-epileptic drug levels in epileptic patients, anoxia-hypoxia, and remote symptomatic. The other etiologies included were alcohol related, trauma, central nervous system infections, tumors, systemic infection, metabolic disorders, idiopathic, and hemorrhage. These observations provide the first direct prospective comparison of SE present in university and private practice community hospital settings in the same geographic area. Mortality was the highest in the elderly population while the pediatric population had low mortality in both clinical settings. Etiology risk factors for outcome were similar for both the populations. The data also suggest that the higher degree of illness severity in university hospitals may be associated with a higher incidence of SE, but not with mortality or a different clinical presentation of the condition. The results of this study demonstrate that SE has the same mortality and is present in an essentially identical manner in university and private practice community hospitals and underscores the fact that mortality in SE is not just associated with tertiary care hospitals and the importance of recognizing the severity of SE in the private practice setting.

Duration of refractory status epilepticus and outcome: loss of prognostic utility after several hours

PURPOSE

Outcome for patients with status epilepticus (SE) depends strongly on etiology. Duration of SE is also predictive, at least in the first 2 h, but beyond this it is unclear that duration of SE influences outcome significantly. We sought to determine the influence of duration of SE on outcome in patients with prolonged SE, and to compare this influence with that of other factors.

METHODS

We reviewed the clinical course and outcome of 119 patients with SE, diagnosed by both clinical manifestations and electroencephalography (EEG) evidence. Using univariate and multivariate analyses, we sought predictors of outcome (survival vs. death or vegetative state) among age, etiology (epilepsy, anoxia or severe hypoxia, or other), presence of earlier epilepsy, multiple medical problems, presentation in coma, and type of SE (focal or generalized).

RESULTS

Median duration of SE was 48 h. Survival was greater with a shorter duration, especially when <10 h (69% vs. 31% for longer duration; p < 0.05). Epilepsy as the etiology, and an earlier diagnosis of epilepsy offered a favorable prognosis (p < 0.01), but only the former on multivariate analysis. Coma and SE caused by anoxia/hypoxia were unfavorable factors. Once corrected for etiology, presentation in coma, and type of SE (focal or generalized), duration of SE did not have a significant effect on outcome. Overall mortality was high, 65%, but 10 patients survived SE lasting over 3.5 days.

CONCLUSIONS

A duration of <10 h was associated with better outcome in SE, but this was not significant once etiology, presentation in coma, and type of SE were accounted for. Etiology of SE is still the primary determinant of outcome. Unless it follows anoxia, prolonged SE should not be considered a hopeless condition.

Status epilepticus in central nervous system infections: an experience from a developing country

OBJECTIVE

There is a paucity of comprehensive study in status epilepticus in central nervous system infections. This observational study evaluated the response to antiepileptic drugs in patients with status epilepticus and central nervous system infection.

METHODS

The study took place at a tertiary care teaching hospital in India. A total of 37 of 93 adult patients (39.8%) with status epilepticus had central nervous system infection, and they underwent clinical evaluation, including status type and duration. Magnetic resonance imaging and cerebrospinal fluid analyses were performed. Patients were categorized into encephalitis, meningitis, and granuloma groups. The response to antiepileptic drugs was noted, and the status was considered refractory if seizures continued after the second antiepileptic drug. Refractory status epilepticus and mortality were correlated with the type of infection and various clinical and magnetic resonance imaging findings.

RESULTS

The median age of the patients was 37 years (16-78 years), and 17 patients were female; 35 patients had convulsive status epilepticus, and 2 patients had nonconvulsive status epilepticus. Twenty patients had encephalitis (Japanese 4, herpes simplex 3, nonspecific 12), including 1 patient with malaria, 9 patients with meningitis (tubercular 5, pyogenic 3, fungal 1), and 7 patients with granuloma (tubercular 5, neurocysticercosis 2). The mean duration of status epilepticus was 19.6 hours (0.25-72 hours). Magnetic resonance imaging results were abnormal in 66.7% of patients. In 67.6% of patients, status epilepticus was controlled after the first antiepileptic drug. Some 24.3% of patients were refractory to the second antiepileptic drug, and 10.8% of patients did not respond to the third antiepileptic drug. Patients with encephalitis had an insignificantly poor response. Eleven patients (29.7%) died, and mortality was higher in patients with refractory status epilepticus.

CONCLUSION

Of patients with status epilepticus and central nervous system infection, 24.3% had a refractory status that was associated with a high mortality. Their response to an antiepileptic drug in encephalitis was insignificantly poorer.

[Clinical characteristics of status epilepticus in an emergency hospital: importance of nonconvulsive status epilepticus]

Although nonconvulsive status epilepticus (NCSE) is a major neurological emergency, its frequency and clinical course are not well clarified. We investigated the clinical characteristics of status epilepticus focusing on the significance of NCSE. One thousand seven hundred twenty-three patients were admitted as neurological emergency cases in our hospital between October 2003 and September 2006. Of these cases, 94 (5.5%) were diagnosed as status epilepticus of which, 24 (25.5%) were diagnosed with NCSE on admission. Moreover, 8 patients who presented with convulsive status epilepticus on admission had episodes of NCSE during hospitalization. Thus, 32 patients (34.0%) suffered from NCSE during their clinical course. We analyzed the prognostic factors of status epilepticus using the Glasgow Outcome Scale. Poor outcome was significantly correlated with NCSE (p = 0.003) and acute cerebrovascular disease (p = 0.010), independent of age, sex, history of epilepsy, and other etiologies. Our study revealed that NCSE is not a rare condition and results in a poor outcome. Careful EEG evaluation of patients with consciousness disturbance might increase the diagnostic accuracy of NCSE, and aggressive treatment of patients with NCSE should be necessary to improve the prognosis of NCSE.

Cognitive outcome of status epilepticus in adults

There is no doubt that structural morphological brain lesions and malformations in epilepsy represent major etiological factors for the cognitive impairments seen in this disease. The role of epileptic activity and seizures for cognition and cognitive development, however, is less easily determined. Epileptic dysfunction ranges from interictal and periictal activity over self-terminating seizures to non-convulsive and convulsive status epilepticus, which appear the most severe conditions along this continuum. The decisive question in this regard is as to whether cognitive impairments observed in the acute epileptic condition are reversible or not. Impairments from interictal or postictal epileptic dysfunction are reversible and may interfere at most with brain maturation and cognitive development in the young patient. Seizures and ictal dysfunction in contrast, even when reversible, can leave a permanent trace which extends the phase of postictal recovery. As for status epilepticus and subsequent cognitive decline it often remains open whether the epileptic condition itself or the underlying clinical condition is causative for the aftermath. While there is evidence for both possibilities, group data from neuropsychological cross sectional and longitudinal studies indicate that more severe mental impairments, which in turn indicate more severe clinical conditions, appear to be a risk factor for sustaining status epilepticus, rather than that status epilepticus causes the cognitive decline. Reviewing the literature the cognitive condition in patients with status epilepticus varies with the type of epilepsy, the etiology of epilepsy, severity of the status, and the age of the patient.

Treatment of acute seizures and status epilepticus

Overt status epilepticus and persistent obtundation after a witnessed clinical seizure are neurologic emergencies. Early recognition and intervention in the electroclinical syndrome of status epilepticus reduces morbidity, although treatment of the underlying etiology is also critical. This review outlines key concepts related to status epilepticus, delineates an approach to the early management of status epilepticus, and highlights novel but practical approaches in the evaluation and treatment of refractory status epilepticus, emphasizing the use of a treatment algorithm. This review is written from the perspective of the intensive care unit clinician, and the approach and opinions expressed stem from clinical experience and review of the current literature. Particular attention is given to an overall approach to the management of convulsive status epilepticus in adults and older children as well as exploring novel approaches and diagnostic tools that may prove useful in difficult-to-control status epilepticus.

Functional and morphological changes in the dentate gyrus after experimental status epilepticus

Status epilepticus may cause long-term functional and structural consequences possibly resulting in brain dysfunctions such as chronic epilepsy. In epileptogenesis, the dentate gyrus plays a key role in regulating the excitability of highly vulnerable and potentially epileptogenic downstream structures in the hippocampus proper. One, four and eight weeks after electrically induced status epilepticus, excitability and neuronal degeneration in the rat dentate gyrus were examined with intracerebral electrodes and Fluoro Jade (FJ) staining, respectively. Half of the animals had developed chronic epilepsy by 8 weeks after status epilepticus. Sham-operated controls did not exhibit seizures, and the excitatory parameters remained unchanged. Compared to controls, 8 weeks after status epilepticus the population spike latency in the dentate gyrus was significantly reduced (p<0.05) and substantial neuronal degeneration was seen (p<0.05). In summary, status epilepticus results in functional and morphological alterations in the dentate gyrus likely contributing to epileptogenesis.

Convulsive status epilepticus: clinical profile in a developing country

PURPOSE

In developing countries optimal care of status epilepticus (SE) is associated with major barriers, particularly transportation.

METHODS

A prospective study of SE was performed between 1994 and 1996 to determine the clinical profile, response to treatment and outcome, Glasgow Outcome Scale (GOS).

RESULTS

Of the 85 patients admitted, the mean age was 33 years (8-75 years), 16% <16 years of age. The mean duration of SE before admission was 18.02 h (1-72 h). Only 23 (28%) patients, all locals, presented within <3 h of onset. Etiology included acute symptomatic (54%), remote symptomatic (7%), cryptogenic (19%), and established epilepsy (20%). Central nervous system infections accounted for 24 (28%) of the etiologies. Seventy-five (88%) patients responded to first-line drugs and 10 (12%) required second-line drugs. The mean duration of SE was significantly long in nonresponders (Mean +/- SD: 32.6 +/- 20.11 vs. 15.2 +/- 18.32, p < 0.006). Duration (p < 0.01; OR 1.04, 95% CI 1.01-1.07) and acute symptomatic etiology (p < 0.038; OR 10.38, 95% CI 1.13-95.09) were the independent predictors of no-response to first-line drugs. Of the nine deaths (10.5%), eight were in acute symptomatic group. Predictors of mortality included female sex (p < 0.017, OR 13.41, 95% CI 1.59-115.38) and lack of response to first-line drugs (p < 0.0001, OR 230.27, 95% CI 8.78-6037.19). Longer duration was associated with poor GOS 1-4 (p = 0.001). Of the 37 patients with <6 h, 81% had GOC5 outcome.

CONCLUSION

This study suggests that longer duration of SE and acute symptomatic etiology are independent predictors of lack of response to first-line drugs. Failure to respond to first-line drugs and duration predict the outcome.

The anaesthetic and intensive care of status epilepticus

PURPOSE OF REVIEW

Status epilepticus refractory to first and second-line anticonvulsants represents an outstanding challenge to the medical team. This review covers new insights into the anaesthetic and intensive care of status epilepticus.

RECENT FINDINGS

In the anaesthetic treatment of status epilepticus, barbiturates, midazolam, or propofol are the drugs of choice, but the lack of controlled prospective data as yet does not allow the recommendation of a preference for one of the substances, unequivocally. Recent observational studies reported on inhalational anaesthetics and supplementary nonanaesthetics such as levetiracetam or topiramate that may be administered if status epilepticus is not controlled by intravenous anaesthetics. Nonpharmacological approaches including resective surgery, brain stimulation, and hypothermia may be applied in selected patients, only. Psychogenic nonepileptic status epilepticus commonly mimics refractory generalized convulsive status epilepticus, and clinical features discerning the two conditions are presented. The underlying cause is the major contributor for a difficult-to-treat 'malignant' course of status epilepticus and together with age determines mortality and functional outcome.

SUMMARY

The common substances administered for the anaesthetic treatment of status epilepticus require assessment in a prospective randomized controlled trial. Alternative pharmacological or nonpharmacological approaches need further studies as well before they can be recommended as part of the therapeutic regime.

The management of refractory status epilepticus: an update

Refractory status epilepticus (RSE) is an important and serious clinical problem that typically requires prolonged and high-level intensive care, and is often associated with poor outcome. This review addresses some of the current issues concerning the management of RSE, including recent definitions used for clinical studies, epidemiology, clinical course, and outcome. Current approaches to treatment, including the now relatively standard use of intravenous anesthetic agents, as well as emerging therapies utilizing drugs such as valproate and topiramate, are discussed as well.

Advances in the management of seizures and status epilepticus in critically ill patients

Seizures and status epilepticus are common in critically ill patients. They can be difficult to recognize because most are non-convulsive and require electroencephalogram monitoring to detect; hence, they are currently underdiagnosed. Early recognition and treatment are essential to obtain maximal response to first-line treatment and to prevent neurologic and systemic sequelae. Anti-seizure medication should be combined with management of the underlying cause and reversal of factors that can lower the seizure threshold, including many medications, fever, hypoxia, and metabolic imbalances. This article discusses specific treatments and specific situations, such as hepatic and renal failure patients and organ transplant patients.

Status epilepticus after stroke is associated with increased long-term case fatality

PURPOSE

The aim of this study was to determine the long-term case fatality of patients with a first episode of status epilepticus (SE group) of cerebrovascular etiology, as compared with that in acute stroke patients without SE (AS group).

METHODS

Patients with SE who had been prospectively admitted to an epidemiologic study were retrospectively compared with a cohort of patients from the local stroke registry. The main outcome end point was overall survival. Survival curves were generated according to the Kaplan-Meier method and compared by using the log-rank test. An extended Cox model was used to examine the impact of patient group on the risk of death. Covariates considered potential confounders included age at diagnosis, sex, type of stroke, affected hemisphere, and localization of lesions.

RESULTS

Of 166 patients who entered the study, 93 patients were in the SE group, and 73 patients were in the AS group; 53 SE patients and 35 AS patients died during the study. Patient group (SE vs. AS) showed no significant impact on survival (p=0.0832) in univariate analysis. In contrast, the results from a multivariable analysis suggest that after 6 months, patients with SE were at about twice the risk of death as were patients with AS [hazard ratio of 2.12 with 95% confidence interval, 1.04-4.32, p=0.0392].

CONCLUSIONS

The occurrence of SE in patients with cerebrovascular disease indicates a high risk of death within 3 years. In contrast, the case fatality risk attributable to recurrent status or seizures is lower.

Temperature regulation is compromised in experimental limbic status epilepticus

Temperature dysregulation is well known in generalized convulsive status epilepticus but so far has not been reported in non-convulsive forms. In order to detect possible subtle alterations, we have analyzed the capability to compensate for external cooling in an animal model of limbic status epilepticus. Rats with electrically induced self-sustaining status epilepticus (SSSE) (n=6) as well as rats without electrical stimulation (n=6) were cooled for 3 h and then rewarmed for another hour. The time course of changes in epidural temperature in animals of both groups that underwent cooling and in control rats that were not cooled and not stimulated (n=6) was compared. In animals with limbic SSSE, temperature fell continuously and was significantly lower at all time points under cooling as compared with each of the two other groups. In animals that were not stimulated, temperature under cooling fell by 1 to 2 degrees C only and was not significantly different at any time point as compared with controls. The effect of cooling was reversible in both groups. The current data indicate that temperature homeostasis in limbic status epilepticus is markedly disturbed. This finding may suggest ictal involvement of primary thermoregulatory neurons in the anterior hypothalamus probably by spread of epileptic activity from temporo-mesial structures.

Transient peripheral leukocytosis in children with afebrile seizures

The purpose of this study was (1) to demonstrate whether peripheral blood leukocytosis accompanies first afebrile seizures without bacterial infection, (2) to investigate the duration of leukocytosis, and (3) to assess the relationship between peripheral blood leukocytosis and seizure characteristics. Complete blood count was routinely obtained from all the patients. Blood and urine cultures were obtained from patients with leukocytosis. On the 24th hour of admission, a second complete blood count was obtained from patients with initial leukocytosis. Sixty-two children aged 4.0 +/- 3.6 years (range, 6 months-13 years)-31 boys (50%) and 31 girls (50%)--enrolled in the study. The findings showed that peripheral blood leukocytosis was found in 8% of afebrile children without status epilepticus and 41.6% of afebrile children with status epilepticus. An interesting finding of the study was that peripheral blood leukocytosis accompanied by afebrile seizures subsided in 24 hours. Transient leukocytosis could be found in children with afebrile seizures without bacterial infection.

[Refractory status epilepticus: diagnosis, therapy, course, and prognosis]

Status epilepticus (SE) is a frequent neurological emergency with an annual incidence of 10-20/100,000 individuals. The overall mortality is about 10-20%. Patients present with long-lasting fits or series of epileptic seizures or extended stupor and coma. Furthermore, patients with SE can suffer from a number of systemic complications possibly also due to side effects of the medical treatment. In the beginning, standardized treatment algorithms can successfully stop most SE. A minority of SE cases prove however to be refractory against the initial treatment and require intensified pharmacologic intervention with nonsedating anticonvulsive drugs or anesthetics. In some partial SE, nonpharmacological approaches (e.g., epilepsy surgery) have been used successfully. This paper reviews scientific evidence of the diagnostic approach, therapeutic options, and course of refractory SE, including nonpharmacological treatment.

Medical management of patients with brain tumors

The most common medical problems in brain tumor patients include the management of seizures, peritumoral edema, medication side effects, venous thromboembolism (VTE), fatigue and cognitive dysfunction. Despite their importance, there are relatively few studies specifically addressing these issues. There is increasing evidence that brain tumor patients who have not had a seizure do not benefit from prophylactic antiepileptic medications. Patients on corticosteroids are at greater risk of Pneumocystis jerovecii pneumonia and may benefit from prophylactic therapy. There is also growing evidence suggesting that anticoagulation may be more effective than inferior vena cava IVC) filtration devices for treating VTE in brain tumor patients and the risk of hemorrhage with anticoagulation is relatively small. Low-molecular weight heparin may be more effective than coumadin. Medications such as modafinil and methylphenidate have assumed an increasing role in the treatment of fatigue, while donepezil and memantine may be helpful with memory loss.

Status epilepticus: pathophysiology and management in adults

As in Clark and Prout's classic work, we identify three phases of generalised convulsive status epilepticus, which we call impending, established, and subtle. We review physiological and subcellular changes that might play a part in the transition from single seizures to status epilepticus and in the development of time-dependent pharmacoresistance. We review the principles underlying the treatment of status epilepticus and suggest that prehospital treatment is beneficial, that therapeutic drugs should be used in rapid sequence according to a defined protocol, and that refractory status epilepticus should be treated with general anaesthesia. We comment on our preference for drugs with a short elimination half-life and discuss some therapeutic choices.

Mortality after a First Episode of Status Epilepticus in the United States and Europe

OBJECTIVE

In the last decade several studies have been published on incidence, etiology, and prognosis of status epilepticus (SE) with population-based data from the United States and Europe. The aim of this review is to summarize the available information on the epidemiology of SE and to outline the sources of the variability in reported mortality after SE.

METHODS

Comparison of mortality studies in SE from the United States and Europe.

RESULTS

The incidence of SE is lower in Europe (9.9-15.8/10,000) than in the United States (18.3-41/100,000). The overall mortality after SE is similar in the two U.S. studies: the case fatality is 21% in Rochester, and 22% in Richmond. All European studies excluded SE after anoxic encephalopathy following cardiac arrest. This exclusion may partly explain the lower case fatality (around 10%) found in two of the European studies. The study from Bologna showed the highest case fatality (33%) even after exclusion of anoxic encephalopathy. The mortality in acute symptomatic SE was higher than for other forms of SE across all studies.

CONCLUSIONS

Short-term mortality after SE occurs mainly in the acute symptomatic group. Based on published data, it is not clear if differences in early management and medical treatment have any impact on prognosis or whether the differences can be attributed only to differences in distribution of the underlying causes in acute symptomatic SE. Future studies should address this issue.

Spatial learning deficits and emotional impairments in pentylenetetrazole-kindled rats

Pentylenetetrazole (PTZ) is a chemical kindling agent used to examine the efficacy of potential anticonvulsants in rats. However, the extent to which PTZ mimics postseizure symptoms of epilepsy has not been thoroughly examined. This study assessed whether PTZ-induced seizures produce cognitive and emotional deficits that mimic those observed in many epileptic patients. Rats were given 30mg/kg PTZ or vehicle (intraperitoneally) every other day for 28 days. Those rats exhibiting consistent seizure activity were tested for learning ability and emotional reactivity, beginning 1 week following a single challenge dose of PTZ. Rats given PTZ made more reference memory errors in a radial arm water maze task, and exhibited emotional abnormalities in the forced swim test, the systematic handling test, and the open-field exploratory maze. Histological analysis revealed neuronal loss in the CA1 area and increased mossy fiber sprouting in the dentate gyrus, similar to what is observed in human epilepsy. These results indicate that PTZ kindling provides a useful model of postseizure dysfunction, which can serve as a screen for potential treatments for those cognitive, emotional, and neuropathological deficits that resemble those symptoms observed in human epilepsy.

Simple partial status epilepticus in Chinese adults

Simple partial status epilepticus (SPSE) is uncommon compared with generalized tonic-clonic status epilepticus. We evaluated the clinical profile and predictors of poor outcome in a group of Chinese patients with this condition. We identified 32 patients above the age of 14 years with SPSE from a large urban hospital over an eleven-year period. Factors for poor outcome, defined as death or morbidity, were analyzed. The most common underlying causes were due to cerebrovascular disease (46.9%), CNS infection (15.6%), metabolic derangement (12.5%) and tumor (12.5%). At 30 days from the onset of seizures, 13(40.5%) patients had recovered fully and seven (21.9%) had died. Poor outcome was associated with the presence of an acute symptomatic injury.

Prolonged refractory status epilepticus following acute traumatic brain injury: a case report of excellent neurological recovery

Introduction

Refractory status epilepticus (RSE) secondary to traumatic brain injury (TBI) may be under-recognized and is associated with significant morbidity and mortality.

Methods

This case report describes a 20 year old previously healthy woman who suffered a severe TBI as a result of a motor vehicle collision and subsequently developed RSE. Pharmacological coma, physiological support and continuous electroencephalography (cEEG) were undertaken.

Results

Following 25 days of pharmacological coma, electrographic and clinical seizures subsided and the patient has made an excellent cognitive recovery.

Conclusion

With early identification, aggressive physiological support, appropriate monitoring, including cEEG, and an adequate length of treatment, young trauma patients with no previous seizure history and limited structural damage to the brain can have excellent neurological recovery from prolonged RSE.

Intellectual Prognosis of Status Epilepticus in Adult Epilepsy Patients: Analysis with Wechsler Adult Intelligence Scale-Revised

PURPOSE

Status epilepticus (SE) appears to cause cognitive dysfunction as well as other serious neurologic sequelae. To confirm whether SE produces a subsequent intellectual decline, we evaluated intellectual function prospectively in adult epilepsy patients with and without SE.

METHODS

Of 1,685 patients with epilepsy who underwent comprehensive neuropsychological testing in two national hospitals in Japan, 15 patients experienced an episode of SE afterward and underwent the second neuropsychological examination after the SE episode. Forty clinically matched patients with epilepsy, but without an episode of SE since their initial neuropsychological examination, were also reevaluated. We compared IQs and subscores from the Wechsler Adult Intelligence Scale-Revised between the two groups by repeated measures analysis of variance. In the patients who experienced an SE episode, SE-related variables (i.e., age at the SE episode and type and duration of SE) and epilepsy-related variables such as epilepsy type, lateralization of EEG abnormalities, the presence of mesial temporal sclerosis, and previous history of SE, were evaluated in relation to intellectual outcome.

RESULTS

Patients with SE, in comparison to those without SE, failed to show any significant post-SE intellectual decline. Furthermore, neither the SE-related variables nor the clinical characteristics were correlated with intellectual outcome.

CONCLUSIONS

Our findings suggest that SE does not lead to a significant intellectual decline in adult patients receiving treatment for epilepsy.

Predictors and prognosis of refractory status epilepticus treated in a neurological intensive care unit

OBJECTIVE

To assess risk factors and prognosis in patients with refractory status epilepticus (RSE).

METHODS

We retrospectively analysed all episodes of status epilepticus (SE) treated between 1993 and 2002 on the neurological intensive care unit (NICU) of the Charite-Universitatsmedizin Berlin. The predictive and prognostic features of RSE were compared with non-RSE (NRSE). All patients with "de novo" SE were followed up to identify the possible development of post-SE symptomatic epilepsy.

RESULTS

A total of 83 episodes fulfilled our criteria of SE. Of these 43% were refractory to first line anticonvulsants. The mean age of patients with SE was 53.3 (SD 19) years, with only two patients younger than 18 years. Encephalitis was significantly more often the primary cause in RSE (p<0.05), whereas low levels of antiepileptic drugs were significantly more often associated with NRSE (p<0.001). Hyponatraemia within the first 24 hours after onset of status activity was significantly more often associated with RSE (p<0.05). In RSE, compared with NRSE, significantly longer duration of seizure activity (p<0.001), more frequent recurrence of epileptic activity within the first 24 hours after the end of seizure activity (p<0.001), longer stay in the NICU and in hospital (p<0.001 and p<0.01, respectively), and more frequent development of symptomatic epilepsy (p<0.05) were seen.

CONCLUSIONS

SE treated in the NICU is frequently refractory to first line anticonvulsant drugs. Encephalitis is a predictor for RSE, which is associated with markedly poor outcome, in particular, the development of post-SE symptomatic epilepsy. Thus prevention of this most severe form of SE should be the primary target of treatment of SE.

A systematic review of the epidemiology of status epilepticus

Population-based data on the incidence, aetiology, and mortality associated with status epilepticus (SE) are required to develop preventative strategies for SE. Through a systematic review, we aimed to assess the methodological quality as well as similarities, and differences between available population based studies in order to arrive at conclusions on the epidemiology of SE. All population-based studies where primary outcome was incidence, aetiology or mortality of SE were identified through a systematic search and synthesized. Methodological quality of studies were independently rated by two examiners using a unique scoring system. Seven population-based projects on SE yielding nine published reports and five abstracts were reviewed. Quality scores were in the range of 19-34 with a possible maximum of 40 (kappa scores 0.67-1.0). The incidence of SE has a bimodal distribution with peaks in children aged less than a year and the elderly. Most SE were acute symptomatic. Short-term mortality was 7.6-22% and long-term mortality was 43%. Age and aetiology were the major determinants of mortality. There are few population-based studies on SE but most are of good quality. Most studies are primarily or exclusively based on adult populations. There is limited information on the association of ethnicity and socio-economic status and SE.

Severe refractory status epilepticus owing to presumed encephalitis

The severe refractory type of status epilepticus is very rare in the pediatric population. Eight children with the severe refractory type of status epilepticus owing to presumed encephalitis are described. The age at the onset of status epilepticus of the eight study children ranged between 2.5 and 15 years. Seven of the eight children presented with fever several days prior to the onset of seizures. A comprehensive clinical and laboratory investigation failed to delineate a cause for their seizures. Burst suppression coma was induced by pentothal, midazolam, propofol, or ketamine in all of the children. The mean duration of anesthesia was 28 days (range 4-62 days), but the seizures persisted in spite of repeated burst suppression cycles in all of them. Two children died. Four of the surviving children continued to suffer from seizures, and cognitive sequelae were present throughout follow-up in four children. In summary, the severe refractory type of status epilepticus of the acute symptomatic type owing to relatively mild encephalitis carries a high mortality rate and poor morbidity in terms of seizures and cognition at follow-up.

Prognostic factors of status epilepticus in children

We retrospectively reviewed the medical records of 189 children who were admitted to the Pediatric Neurology Department at Yonsei University College of Medicine with status epilepticus (SE) between April, 1994 and April, 2003. The children were followed up for a mean duration of 17 months. We analyzed the clinical findings and the relationships between neurologic sequelae, recurrence, age of onset, presumptive causes, types of seizure, seizure duration and the presence of fever. Mean age at SE onset was 37 months. Incidences by seizure type classification were generalized convulsive SE in 73.5%, and non-convulsive SE in 26.5%. The incidences of presumptive causes of SE were idiopathic 40.7%, epilepsy 29.1%, remote 16.4% and acute symptomatic in 13.3%. Among all the patients, febrile episodes occurred in 35.4%, especially in patients under 3 year old, and 38.4% of these were associated with febrile illness regardless of presumptive cause. Neurologic sequelae occurred in 33% and the mortality rate was 3%. Neurologic sequelae were lower in patients that presented with an idiopathic etiology and higher in generalized convulsive SE patients. The recurrence of SE was higher in patients with a remote symptomatic epileptic etiology, and generalized convulsive SE showed higher rates of recurrence. Based on this retrospective study, the neurologic outcomes and recurrence of SE were found to be strongly associated with etiology and seizure type. Age, seizure duration and the presence of febrile illness were found to have no effect on outcome.

Limbic Self-sustaining Status Epilepticus in Rats Is Not Associated with Hyperthermia

PURPOSE

To evaluate the impact of limbic status epilepticus on temperature.

METHODS

The perforant path in freely moving rats was stimulated electrically for 120 min to induce self-sustaining status epilepticus (SSSE). For 150 min after the end of stimulation, epidural temperature and electrographic and clinical seizure activity were assessed in animals with limbic and motor SSSE, as well as in animals without development of SE.

RESULTS

Temperature in all animals with SSSE was elevated by 1.5+/-0.8 degrees C after the end of stimulation compared with baseline values (p<0.01). In animals with pure limbic SE, temperature decreased continuously to baseline values over the 150-min period of observation. In contrast, in animals with motor SSSE, temperature remained elevated during continuing epileptic activity and was still significantly higher 150 min after the end of stimulation compared with baseline (p<0.01). In animals that did not develop SSSE, temperature was not changed after the end of electrical stimulation and in the 150 min thereafter compared with baseline values.

CONCLUSIONS

The results indicate that hyperthermia as seen in SE is the consequence of motor convulsions and not of epileptic activity itself, as seen in limbic SSSE.