Progress in clinical neurosciences: Status epilepticus: a critical review of management options

Neurologic complications in critically ill pregnant patients

Neurologic complications in a critically ill pregnant woman are uncommon but some of the complications (such as eclampsia) are unique to pregnancy and the puerperal period. Other neurologic complications (such as seizures in the setting of epilepsy) may worsen during pregnancy. Clinical signs and symptoms such as seizure, headache, weakness, focal neurologic deficits, and decreased level of consciousness require careful consideration of potential causes to ensure prompt treatment measures are instituted to prevent ongoing neurologic injury. Clinicians should be familiar with syndromes such as pre-eclampsia, eclampsia, stroke, posterior reversible encephalopathy syndrome, and reversible cerebral vasoconstriction syndrome. Necessary imaging studies can usually be performed safely in pregnancy. Scoring systems for predicting maternal mortality are inadequate, as are recommendations for neurorehabilitation. Tensions can arise when there is conflict between the interests of the mother and the interests of the fetus, but in general maternal health is prioritized. The complexity of care requires a multidisciplinary and multiprofessional approach to achieve best outcome in an often unexpected situation.

Third-line antiepileptic therapy and outcome in status epilepticus: the impact of vasopressor use and prolonged mechanical ventilation

OBJECTIVES

To characterize associations between antiepileptic drugs with sedating or anesthetic effects (third-line antiepileptic drugs) vs. other antiepileptic agents, and short-term outcomes, in status epilepticus. Furthermore, to evaluate the role of adverse hemodynamic and respiratory effects of these agents in status epilepticus treatment.

DESIGN

Retrospective comparative analysis.

SETTING

Tertiary academic medical center with two emergency departments and two neurologic intensive care units.

PATIENTS

Adults admitted with a diagnosis of status epilepticus defined as seizures lasting continuously >5 mins, or for discrete periods in succession.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Of 126 patients with 144 separate status epilepticus admissions, 57 were female (45%) with mean age 54.7 ± 15.7 yrs. Status epilepticus was convulsive in 132 cases (92%). Status epilepticus etiologies included subtherapeutic antiepileptic drugs (43%), alcohol or other nonantiepileptic drug (13%), and acute central nervous system disease (12%). Third-line antiepileptic drugs were administered in 47 cases (33%). Seventy-eight status epilepticus episodes (54%) had good outcomes (Glasgow Outcome Score = 1, 2) at the time of hospital discharge. On univariate analysis, poor outcome (Glasgow Outcome Score > 2) was associated with older age (mean 59.8 ± 15.5 vs. 50.5 ± 13.8 yrs, p < .001), acute central nervous system disease (21% vs. 4%, p = .001), mechanical ventilation (76% vs. 53%, p = .004), longer duration of ventilation (median 10 days [range 1-56] vs. 2 days [range 1-10], p < .001), treatment with vasopressors (35% vs. 5%, p < .001), and treatment with third-line antiepileptic drugs (51% vs. 17%, p < .001). Death was associated with acute central nervous system disease, prolonged ventilation, treatment with vasopressors, and treatment with third-line antiepileptic drugs. Predictors of poor outcome among all status epilepticus episodes were older age (odds ratio 1.06; 95% confidence interval 1.03-1.09; p < .001), treatment with third-line antiepileptic therapy (odds ratio 5.64; 95% confidence interval 2.31-13.75; p < .001), and first episode of status epilepticus (odds ratio 3.73; 95% confidence interval 1.38-10.10; p = .010). Among status epilepticus episodes treated by third-line antiepileptic drugs, predictors of poor outcome were older age (odds ratio, 1.09; 95% confidence interval 1.01-1.18; p = .038) and longer ventilation (odds ratio, 1.47; 95% confidence interval 1.08-2.00; p = .015). Predictors of mortality among all status epilepticus episodes were treatment with third-line antiepileptic drugs (odds ratio, 12.08; 95% confidence interval 2.30-63.39; p = .003) and older age (odds ratio, 1.06; 95% confidence interval 1.00-1.12; p = .045).

CONCLUSIONS

Third-line antiepileptic drug therapies with sedating or anesthetic effects predicted poor outcome and death in status epilepticus. Hypotension requiring vasopressor therapy and duration of mechanical ventilation induced by these agents may be contributing factors, especially when pentobarbital is used. These findings may inform decision making on drug therapy in status epilepticus and help develop safer and more effective treatment strategies to improve outcome.

Intracerebral hemorrhage specific intensity of care quality metrics

BACKGROUND

Intracerebral hemorrhage (ICH) care can vary among centers and previous studies have demonstrated differences in ICH outcome based on variations in patient care in various settings. The purpose of this paper is to present the design of an evidence-based dataset of elements of a new ICH specific intensity of care quality metrics.

METHODS

The articles were identified based on personal knowledge of the subject supplemented by data derived from multi-center randomized trials, and selected non-randomized or observational clinical studies. The information was identified with multiple searches on MEDLINE from 1986 through 2009. The current guidelines from American Heart Association (AHA)/American Stroke Association (ASA) Stroke Council and The European Stroke Initiative (EUSI) Writing Committee for management of ICH were reviewed extensively for identifying quality indicators and available scientific evidence. For certain elements where stroke-specific data was not available, data derived from other disease process with direct relevance was used.

RESULTS

A total of 26 quality indicators related to 18 facets of care with thresholds for quality response were identified. A pilot study was performed to asses and score 1300 (26 indicator per patientX25 patientsX2 raters) quality indicators. The minimum proportion of patients meeting quality parameter ranged from 44% to 100% depending upon the variable. The lowest performance scores were observed in the early intubation and mechanical ventilation, treatment of significant intracranial mass effect or transtentorial herniation, and timely acquisition of neuroimaging. The highest performance scores were seen in treatment of any seizure within 2 weeks of admission, status epilepticus, and prevention of gastric ulcer.

CONCLUSIONS

The next step in development of a new ICH specific intensity of care quality metrics is validation and refinement of the quality indicators and thresholds presented in the current report. Future activities may include selection and validation based on consensus of experts and application of the system to a large series of patients with ICH and assessment of relationship of components in isolation and as a group to outcome after severity adjustment.

Protective effects of S+ ketamine and atropine against lethality and brain damage during soman-induced status epilepticus in guinea-pigs

Soman poisoning is known to induce full-blown tonic-clonic seizures, status epilepticus (SE), seizure-related brain damage (SRBD) and lethality. Previous studies in guinea-pigs have shown that racemic ketamine (KET), with atropine sulfate (AS), is very effective in preventing death, stopping seizures and protecting sensitive brain areas when given up to 1h after a supra-lethal challenge of soman. The active ketamine isomer, S(+) ketamine (S-KET), is more potent than the racemic mixture and it also induces less side-effects. To confirm the efficacy of KET and to evaluate the potential of S-KET for delayed medical treatment of soman-induced SE, we studied different S-KET dose regimens using the same paradigm used with KET. Guinea-pigs received pyridostigmine (26 microg/kg, IM) 30min before soman (62 microg/kg, 2 LD(50), IM), followed by therapy consisting of atropine methyl nitrate (AMN) (4 mg/kg, IM) 1min following soman exposure. S-KET, with AS (10mg/kg), was then administered IM at different times after the onset of seizures, starting at 1h post-soman exposure. The protective efficacy of S-KET proved to be comparable to KET against lethality and SRBD, but at doses two to three times lower. As with KET, delaying treatment by 2h post-poisoning greatly reduced efficacy. Conditions that may have led to an increased S-KET brain concentration (increased doses or number of injections, adjunct treatment with the oxime HI-6) did not prove to be beneficial. In summary, these observations confirm that ketamine, either racemic or S-KET, in association with AS and possibly other drugs, could be highly effective in the delayed treatment of severe soman intoxication.

Incidence of infections in patients with status epilepticus requiring intensive care and effect on resource utilization

Data from a six-year period were retrospectively retrieved from medical records and an intensive care unit data management system to study the impact of infections on patients with status epilepticus. Out of 161 admitted patients, 33 had a community-acquired infection and 35 acquired an infection during their hospital stay, 10 while in a ward before admission to the intensive care unit and 25 while in an intensive care unit, giving an infection rate of 42% of all admissions (68 patients). The patients with intensive care unit-acquired infection had three times longer stays in the intensive care unit than those without any infection (P<0.001), and they utilized almost four times more nursing resources than those without infections (P<0.001). Furthermore, they were more often sedated with thiopentone infusion, either alone or in combination with other drugs, than the non-infectious patients (80% vs 20%, P <0.001). Both community- and hospital-acquired infections were related to longer intensive care unit stays (P<0.001). The hospital stay of patients with hospital-acquired infection was threefold compared to that of patients without infection (P<0.001), and these patients utilized almost three times more nursing resources than those without any infection (P<0.001). Patients with infections consumed 65.5% of the intensive care unit nursing resources of status epilepticus patients. In conclusion, the infection rate of status epilepticus patients was high and nosocomial infections were associated with more severe illness, treatment escalation, prolonged hospital stay and enhanced resource utilization.

Prolonged coma from refractory status epilepticus

OBJECTIVE

Status epilepticus is a life-threatening medical condition. In its most severe form, refractory status epilepticus (RSE) seizures may not respond to first and second-line anti-epileptic drugs. RSE is associated with a high mortality and significant medical complications in survivors with prolonged hospitalizations.

METHODS

We describe the clinical course of RSE in the setting of new onset lupus in a 31-year-old male who required prolonged barbiturate coma.

RESULTS

Seizure stopped on day 64 of treatment. Prior to the resolution of seizures, discussion around withdrawal of care took place between the physicians and patient's family. Medical care was continued because of the patient's age, normal serial MRI studies, and the patient's reversible medical condition.

CONCLUSION

Few evidence-based data exist to guide management of RSE. Our case emphasizes the need for continuous aggressive therapy when neuroimaging remains normal.

The interpretation of the EEG in stupor and coma

This review discusses a variety of causes of stupor and coma and associated electroencephalographic (EEG) findings. These include metabolic disturbances such as hepatic or renal dysfunction, which are often characterized by slowing of background rhythms and triphasic waves. Hypoxia and drug intoxications can produce a number of abnormal EEG patterns such as burst suppression, alpha coma, and spindle coma. Structural lesions, either supra- or infratentorial, are reviewed. EEGs in the former may show focal disturbances such as delta and theta activity, epileptiform abnormalities, and attenuation of faster frequencies. In infratentorial lesions, the EEG may appear normal, particularly with a pontine lesion. Some patients may be encephalopathic because of ongoing epileptic activity with minimal or no motor movements. This entity, nonconvulsive status epilepticus (NCSE), is difficult to diagnose in obtunded/comatose patients, and an EEG is required to verify the diagnosis and to monitor treatment. Several EEG patterns and their interpretation in suspected cases of NCSE such as periodic lateralized epileptiform discharges (PLEDs), bilateral independent periodic lateralized epileptiform discharges (BIPLEDs), generalized periodic epileptiform discharges (GPEDs), and triphasic waves are reviewed. Other entities discussed include the locked-in syndrome, neocortical death, persistent vegetative state, brainstem death, and brain death.

Efficacy of the ketamine-atropine combination in the delayed treatment of soman-induced status epilepticus

Nerve agent poisoning is known to induce full-blown seizures, seizure-related brain damage (SRBD), and lethality. Effective and quick management of these seizures is critical. In conditions of delayed treatment, presently available measures are inadequate calling for optimization of therapeutic approaches. The effects of ketamine/atropine sulfate (KET/AS) combinations were thus assessed as potential valuable delayed therapy in soman-poisoned male guinea pigs. Animals received pyridostigmine (26 microg/kg, i.m.) 30 min before soman (62 microg/kg, i.m.) followed by therapy consisting of atropine methyl nitrate (4 mg/kg) 1 min later. KET was then administered i.m. at different times after the onset of seizures, starting at 30 min post-poisoning. KET was always injected with atropine sulfate, itself given at a dose that was unable to modify seizures (2 to 10 mg/kg). Different treatment schemes (dose and time of injection) were evaluated. Sub-anesthetic doses of KET (10 mg/kg) could prevent lethality and stop ongoing seizures only when administered 30 min after challenge. An extended delay before treatment (up to 2 h) called for an increase in KET dose (up to 60 mg/kg three times), thus reaching anesthetic levels but without the need of any ventilation support. KET proved effective in stopping seizures, highly reducing SRBD and allowing survival with a progressive loss of efficacy when treatment was delayed beyond 1 h post-challenge. Preliminary results suggest that association with the benzodiazepine midazolam (1 mg/kg) might be interesting when treatment is initiated 2 h after poisoning, i.e., when KET efficacy is dramatically reduced. All in all, these observations suggest that KET, in association with atropine sulfate and possibly other drugs, may be highly effective in the delayed treatment of severe soman intoxication.

Treatment of Refractory Status Epilepticus with Hemispherectomy

A 7-year-old boy with left hemiparesis secondary to right hemispheric cortical dysplasia was admitted to the hospital with increasing numbers of seizures. Magnetic resonance imaging showed a small dysplastic right hemisphere with abnormally thickened gyri and an apparently normal left hemisphere. Previous video-electroencephalogram (EEG) monitoring showed bilateral independent spikes and generalized slow spike-and-wave episodes on EEG and [18F]fluorodeoxyglucose (FDG) positron emission tomography scan demonstrated scattered areas of regional hypometabolism bilaterally; therefore hemispherectomy was not undertaken at that time. During this hospital stay, nonconvulsive status epilepticus developed and was refractory to multiple medical therapies including pentobarbital (PTB) coma. Burst-suppression pattern during PTB coma appeared to be generalized spike and wave, but when EEG was reviewed with increased time resolution spikes suggested a right hemisphere origin. The patient underwent bilateral intracarotid amobarbital spike-suppression test that showed only minimal suppression of epileptiform discharges with injection of the left carotid, but complete suppression of spike activity after right-sided carotid injection. A right hemispherectomy was performed with complete cessation of status epilepticus. Postoperative EEG showed no epileptiform discharges. Patient follow-up was limited to 12 months after surgery. The patient had regained the ability to walk unaided and was seizure free with a single antiepileptic medication. This case illustrates a potentially life-saving procedure for refractory status epilepticus and several techniques including a spike-suppression test to aid in prediction of cessation of seizures after hemispherectomy.