Status epilepticus

Status Epilepticus in Older Adults: Diagnostic and Treatment Considerations

Status epilepticus (SE) is one of the leading life-threatening neurological emergencies in the elderly population, with significant morbidity and mortality. SE presents unique diagnostic and therapeutic challenges in the older population given overlap with other causes of encephalopathy, complicating diagnosis, and the common occurrence of multiple comorbid diseases complicates treatment. First-line therapy involves the use of rescue benzodiazepine in the form of intravenous lorazepam or diazepam, intramuscular or intranasal midazolam and rectal diazepam. Second-line therapies include parenteral levetiracetam, fosphenytoin, valproate and lacosamide, and underlying comorbidities guide the choice of appropriate medication, while third-line therapies may be influenced by the patient's code status as well as the cause and type of SE. The standard of care for convulsive SE is treatment with an intravenous anesthetic, including midazolam, propofol, ketamine and pentobarbital. There is currently limited evidence guiding appropriate therapy in patients failing third-line therapies. Adjunctive strategies may include immunomodulatory treatments, non-pharmacological strategies such as ketogenic diet, neuromodulation therapies and surgery in select cases. Surrogate decision makers should be updated early and often in refractory episodes of SE and informed of the high morbidity and mortality associated with the disease as well as the high probability of subsequent epilepsy among survivors.

Rates and Trends of Endotracheal Intubation in Patients With Status Epilepticus

OBJECTIVE

Among patients with status epilepticus, we sought to determine the rate of endotracheal intubation, identify the physician specialties responsible for endotracheal intubation, and characterize the trend in use of endotracheal intubation over the last 20 years.

METHODS

We performed a cross-sectional study using data from 2 sources. First, we used inpatient claims between 2009 and 2015 from a nationally representative 5% sample of Medicare beneficiaries. Patients with status epilepticus were identified using International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) codes, and those who underwent endotracheal intubation were identified based on Current Procedural Terminology codes. Medical specialties of providers performing intubation were identified based on Healthcare Provider Taxonomy Codes. Second, we used claims data from the National Inpatient Sample (NIS) to estimate the annual rates and trends of endotracheal intubation and tracheostomy among patients with status epilepticus from 1995 to 2014.

RESULTS

Among 1971 Medicare beneficiaries with status epilepticus, 566 (29%) patients underwent endotracheal intubation. 375 (66%) patients were intubated on admission. The most common medical providers performing intubation in patients with status epilepticus were emergency medicine physicians (50.4%), anesthesiologists (16.4%), and pulmonary medicine physicians (10.1%). Neurologists accounted for 1.7% of all intubations. Among individuals with status epilepticus identified in the NIS, 248 681 (41.7%) were intubated. The proportion of patients intubated increased from 29.5% (95% confidence interval [CI]: 27.8%-31.3%, P = .018) in 1995 to 50.8% (95% CI: 49.6%-52%, P = .012) in 2014. The proportion of patients with status epilepticus who underwent tracheostomy increased from 2.2% (95% CI: 1.7%-2.7%, P = .005) in 1995 to 3.4% (95% CI: 3%-3.9%, P = .004) in 2014.

SIGNIFICANCE

Approximately 1 in 3 patients with status epilepticus undergo endotracheal intubation. Over the last 20 years, the proportion of patients with status epilepticus undergoing endotracheal intubation has almost doubled. Neurologists perform a small percentage of these intubations.

Long-Term Effects of Early Life Seizures on Endogenous Local Network Activity of the Mouse Neocortex

Understanding the long term impact of early life seizures (ELS) is of vital importance both for researchers and clinicians. Most experimental studies of how seizures affect the developing brain have drawn their conclusions based on changes detected at the cellular or behavioral level, rather than on intermediate levels of analysis, such as the physiology of neuronal networks. Neurons work as part of networks and network dynamics integrate the function of molecules, cells and synapses in the emergent properties of brain circuits that reflect the balance of excitation and inhibition in the brain. Therefore, studying network dynamics could help bridge the cell-to-behavior gap in our understanding of the neurobiological effects of seizures. To this end we investigated the long-term effects of ELS on local network dynamics in mouse neocortex. By using the pentylenetetrazole (PTZ)-induced animal model of generalized seizures, single or multiple seizures were induced at two different developmental stages (P9-15 or P19-23) in order to examine how seizure severity and brain maturational status interact to affect the brain's vulnerability to ELS. Cortical physiology was assessed by comparing spontaneous network activity (in the form of recurring Up states) in brain slices of adult (>5 mo) mice. In these experiments we examined two distinct cortical regions, the primary motor (M1) and somatosensory (S1) cortex in order to investigate regional differences in vulnerability to ELS. We find that the effects of ELSs vary depending on (i) the severity of the seizures (e.g., single intermittent ELS at P19-23 had no effect on Up state activity, but multiple seizures induced during the same period caused a significant change in the spectral content of spontaneous Up states), (ii) the cortical area examined, and (iii) the developmental stage at which the seizures are administered. These results reveal that even moderate experiences of ELS can have long lasting age- and region-specific effects in local cortical network dynamics.

Endotracheal Intubation in Patients Treated for Prehospital Status Epilepticus

INTRODUCTION

Limited data describe the frequency, timing, or indications for endotracheal intubation (ETI) in patients with status epilepticus. A better understanding of the characteristics of patients with status epilepticus requiring airway interventions could inform clinical care. We sought to characterize ETI use in patients with prehospital status epilepticus.

METHODS

This study was a secondary analysis of the Rapid Anticonvulsant Medication Prior to Arrival Trial, a multi-center, randomized trial comparing intravenous lorazepam to intramuscular midazolam for prehospital status epilepticus treatment. Subjects received ETI in the prehospital, Emergency Department (ED), or inpatient setting at the discretion of caregivers.

RESULTS

Of 1023 enrollments, 218 (21 %) received ETI. 204 (93.6 %) of the ETIs were performed in the hospital and 14 (6.4 %) in the prehospital setting. Intubated patients were older (52 vs 41 years, p < 0.001), and men underwent ETI more than women (26 vs 21 %, p = 0.047). Patients with ongoing seizures on ED arrival had a higher rate of ETI (32 vs 16 %, p < 0.001), as did those who received rescue anti-seizure medication (29 vs 20 %, p = 0.004). Mortality was higher for intubated patients (7 vs 0.4 %, p < 0.001). Most ETI (n = 133, 62 %) occurred early (prior to or within 30 min after ED arrival), and late ETI was associated with higher mortality (14 vs 3 %, p = 0.002) than early ETI.

CONCLUSIONS

ETI is common in patients with status epilepticus, particularly among the elderly or those with refractory seizures. Any ETI and late ETI are both associated with higher mortality.

Status epilepticus: an update

Status epilepticus (SE) still results in significant mortality and morbidity. Whereas mortality depends mainly on the age of the patient as well as the cause, morbidity is often due to the 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 has recently changed to incorporate four stages and must be initiated at the earliest possible time.

Management of status epilepticus in neurological versus medical intensive care unit: does it matter?

BACKGROUND

Admission of patients with status epilepticus (SE) to the neurosciences intensive care unit (NICU) may improve management and outcomes compared to general ICUs.

METHODS

We reviewed all patients with SE admitted to the NICU versus the Medical ICU in our institution between 2005 and 2008. We included only patients with definite or probable SE based on pre-defined criteria. We collected demographic and clinical data, including severity of admission scores and adjusted short-term outcomes for admission and management in the two ICUs.

RESULTS

There were 168 visits in 151 patients for definite or probable SE, 46 (27 %) of which were in the NICU and 122 (73 %) in the MICU. APACHE II scores were significant higher in the MICU group (17.5 vs 13.4, p = 0.003) and age in the NICU (58.3 vs 51.5 years, p = 0.041). More continuous EEGs were ordered in the NICU (85 vs 30 %, p < 0.001), where fewer patients were intubated, but more eventually tracheostomized. The NICU had a higher rate of complex partial SE and more alert or somnolent patients, whereas the MICU had a higher rate of generalized SE and more stuporous or comatose patients. Admission diagnoses also differed, with the NICU having higher rate of strokes and the MICU higher rate of toxometabolic etiologies (39 vs 12 % and 11 vs 21 %, p = 0.002). After adjustment, no difference was found in mortality, the ICU or hospital length of stay and modified Rankin score at discharge.

CONCLUSION

SE treatment revealed increased use of continuous EEG in NICU-admitted patients, but without concomitant reduction in LOS or discharge outcomes compared to the MICU.

Status epilepticus in the elderly: epidemiology, clinical aspects and treatment

The aim of the study was to review the epidemiology, clinical profile and discuss the etiology, prognosis and treatment options in patients aged 60 years or older presenting with status epilepticus. We performed a systematic review involving studies published from 1996 to 2010, in Medline/PubMed, Scientific Electronic Library on line (Scielo), Latin-American and Caribbean Center of Health Sciences Information (Lilacs) databases and textbooks. Related articles published before 1996, when relevant for discussing epilepsy in older people, were also included. Several population studies had shown an increased incidence of status epilepticus after the age of 60 years. Status epilepticus is a medical and neurological emergency that is associated with high morbidity and mortality, and is a major concern in the elderly compared to the general population. Prompt diagnosis and effective treatment of convulsive status epilepticus are crucial to avoid brain injury and reduce the fatality rate in this age group.

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.

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.