Etiology of a short-term mortality in the group of 750 patients with 920 episodes of status epilepticus within a period of 10 years (1988–1997)

Status epilepticus without impairment of consciousness: Long-term outcomes according to duration

OBJECTIVE

The point after which non-convulsive status epilepticus (NCSE) can cause permanent damage remains to be elucidated. The aim of this study was to analyze the association between time to resolution and long-term outcomes in NCSE.

METHODS

We performed a retrospective study of all patients with focal NCSE without consciousness impairment at two tertiary care hospitals in Spain. All the data were registered prospectively and the study period was December 2014-May 2018. We collected information on demographics, SE etiology, time to administration of different lines of treatment, time to NCSE resolution, and outcomes at discharge, 1 year, and 4 years. Clinical outcome was prospectively categorized as good (return to baseline function) or poor (new disability and death).

RESULTS

Seventy-four patients with a mean (±SD) age of 63.4 ± 17.5 years and a mean follow-up time of 2.4 ± 2.2 years were studied. A poor outcome at discharge was associated with a potentially fatal etiology (p < 0.001), EMSE score (Epidemiology-based Mortality Score in Status Epilepticus) (p = 0.012), lateral periodic discharges on EEG (p = 0.034), and occurrence of major complications during hospitalization (p = 0.007). An SE duration of >100 h was clearly associated with a worse outcome (p < 0.001). In the multiple regression analysis, the only independent predictors of a poor outcome at discharge were an SE duration of >+100 hours (p = 0.001), a potentially fatal etiology (p = 0.001), and complications during hospitalization (p = 0.010). An SE duration of >100 hours retained its value as the optimal cutoff point for predicting poor outcomes at both 1 year (p = 0.037) and 4 years (p = 0.05). Other predictors of poor long-term outcomes were a potentially fatal etiology (p < 0.001) and EMSE score (p = 0.034) at 1 year, and progressive symptomatic etiology at 4 years (p = 0.025).

SIGNIFICANCE

In patients with focal NCSE without consciousness impairment, a potentially fatal etiology and an SE duration of >100 h were associated with poor short-term and long-term outcomes.

Treatment of Refractory and Super-refractory Status Epilepticus

Refractory and super-refractory status epilepticus (SE) are serious illnesses with a high risk of morbidity and even fatality. In the setting of refractory generalized convulsive SE (GCSE), there is ample justification to use continuous infusions of highly sedating medications-usually midazolam, pentobarbital, or propofol. Each of these medications has advantages and disadvantages, and the particulars of their use remain controversial. Continuous EEG monitoring is crucial in guiding the management of these critically ill patients: in diagnosis, in detecting relapse, and in adjusting medications. Forms of SE other than GCSE (and its continuation in a "subtle" or nonconvulsive form) should usually be treated far less aggressively, often with nonsedating anti-seizure drugs (ASDs). Management of "non-classic" NCSE in ICUs is very complicated and controversial, and some cases may require aggressive treatment. One of the largest problems in refractory SE (RSE) treatment is withdrawing coma-inducing drugs, as the prolonged ICU courses they prompt often lead to additional complications. In drug withdrawal after control of convulsive SE, nonsedating ASDs can assist; medical management is crucial; and some brief seizures may have to be tolerated. For the most refractory of cases, immunotherapy, ketamine, ketogenic diet, and focal surgery are among several newer or less standard treatments that can be considered. The morbidity and mortality of RSE is substantial, but many patients survive and even return to normal function, so RSE should be treated promptly and as aggressively as the individual patient and type of SE indicate.

Outcomes of patients with altered level of consciousness and abnormal electroencephalogram: A retrospective cohort study

INTRODUCTION

Nonconvulsive seizures (NCS) are frequent in hospitalized patients and may further aggravate injury in the already damaged brain, potentially worsening outcomes in encephalopathic patients. Therefore, both early seizure recognition and treatment have been advocated to prevent further neurological damage.

OBJECTIVE

Evaluate the main EEG patterns seen in patients with impaired consciousness and address the effect of treatment with antiepileptic drugs (AEDs), continuous intravenous anesthetic drugs (IVADs), or the combination of both, on outcomes.

METHODS

This was a single center retrospective cohort study conducted in a private, tertiary care hospital. Consecutive adult patients with altered consciousness submitted to a routine EEG between January 2008 and February 2011 were included in this study. Based on EEG pattern, patients were assigned to one of three groups: Group Interictal Patterns (IP; EEG showing only interictal epileptiform discharges or triphasic waves), Group Rhythmic and Periodic Patterns (RPP; at least one EEG with rhythmic or periodic patterns), and Group Ictal (Ictal; at least one EEG showing ictal pattern). Groups were compared in terms of administered antiepileptic treatment and frequency of unfavorable outcomes (modified Rankin scale ≥3 and in-hospital mortality).

RESULTS

Two hundred and six patients (475 EEGs) were included in this analysis. Interictal pattern was observed in 35.4% (73/206) of patients, RPP in 53.4% (110/206) and ictal in 11.2% (23/206) of patients. Treatment with AEDs, IVADs or a combination of both was administered in half of the patients. While all Ictal group patients received treatment (AEDs or IVADs), only 24/73 (32.9%) IP group patients and 55/108 (50.9%) RPP group patients were treated (p<0.001). Hospital length of stay (LOS) and frequency of unfavorable outcomes did not differ among the groups. In-hospital mortality was higher in IVADs treated RPP patients compared to AEDs treated RPP patients [11/19 (57.9%) vs. 11/36 (30.6%) patients, respectively, p = 0.049]. Hospital LOS, in-hospital mortality and frequency of unfavorable outcomes did not differ between Ictal patients treated exclusively with AEDs or IVADs.

CONCLUSION

In patients with acute altered consciousness and abnormal routine EEG, antiepileptic treatment did not improve outcomes regardless of the presence of periodic, rhythmic or ictal EEG patterns.

Predictive value of the Status Epilepticus Severity Score (STESS) and its components for long-term survival

Background

The “Status Epilepticus Severity Score” (STESS) is the most important clinical score to predict in-hospital mortality of patients with status epilepticus (SE), but its prognostic relevance for long-term survival is unknown. This study therefore examined if STESS and its components retain their prognostic relevance beyond acute treatment.

Methods

One hundred twenty-five non-anoxic patients with SE were retrospectively identified in two hospitals between 2008 and 2014 (39.2 % refractory SE). Patients’ treatment, demographic data, date of death, aetiology of SE, and the components of the STESS (age, history of seizures, level of consciousness and worst seizure type) were determined based on the patients’ records.

Results

In 94.4 % of patients, SE was treated successfully; in-hospital mortality rate was 12 %. The overall mortality was 42 % after median follow-up of 28.1 months. The survival plateaued after about 3 years, all patients with progressive brain diseases (n = 4) died within one year. In-hospital mortality correlated highly significantly with STESS, the optimal cut-off was 4. With respect to long-term outcome, STESS correlated significantly with overall mortality though with lower odds ratios. When looking only at patients that survived the acute phase of treatment, only the STESS components “level of consciousness” (at admission), “coma” as worst seizure type, and “age” reached a statistical significant association with mortality. In these patients, STESS with a cut-off of 4 was not significantly associated with survival/mortality. Aetiology of SE was insufficient to explain the weak association and the high mortality after discharge alone.

Conclusion

STESS at onset of SE reliably assessed in-hospital mortality, and was indicative for overall survival. However, STESS did not allow correct estimation of mortality after discharge. The high mortality after discharge and high overall mortality of patients diagnosed with SE was not explained by progressive brain disorders alone. Further research is needed to understand the causes for high overall mortality after SE and putative prognostic factors.

Electronic supplementary material

The online version of this article (doi:10.1186/s12883-016-0730-0) contains supplementary material, which is available to authorized users.

Therapeutic coma for status epilepticus: Differing practices in a prospective multicenter study

OBJECTIVE

Our aim was to analyze and compare the use of therapeutic coma (TC) for refractory status epilepticus (SE) across different centers and its effect on outcome.

METHODS

Clinical data for all consecutive adults (>16 years) with SE of all etiologies (except postanoxic) admitted to 4 tertiary care centers belonging to Harvard Affiliated Hospitals (HAH) and the Centre Hospitalier Universitaire Vaudois (CHUV) were prospectively collected and analyzed for TC details, mortality, and duration of hospitalization.

RESULTS

Two hundred thirty-six SE episodes in the CHUV and 126 in the HAH were identified. Both groups were homogeneous in demographics, comorbidities, SE characteristics, and Status Epilepticus Severity Score (STESS); TC was used in 25.4% of cases in HAH vs 9.75% in CHUV. After adjustment, TC use was associated with younger age, lower Charlson Comorbidity Index, increasing SE severity, refractory SE, and center (odds ratio 11.3 for HAH vs CHUV, 95% confidence interval 2.47-51.7). Mortality was associated with increasing Charlson Comorbidity Index and STESS, etiology, and refractory SE. Length of stay correlated with STESS, etiology, refractory SE, and use of TC (incidence rate ratio 1.6, 95% confidence interval 1.22-2.11).

CONCLUSIONS

Use of TC for SE treatment seems markedly different between centers from the United States and Europe, and did not affect mortality considering the whole cohort. However, TC may increase length of hospital stay and related costs.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that for patients with SE, TC does not significantly affect mortality. The study lacked the precision to exclude an important effect of TC on mortality.

Pharmacotherapy for Status Epilepticus

Status epilepticus (SE) represents the most severe form of epilepsy. It is one of the most common neurologic emergencies, with an incidence of up to 61 per 100,000 per year and an estimated mortality of 20 %. Clinically, tonic-clonic convulsive SE is divided into four subsequent stages: early, established, refractory, and super-refractory. Pharmacotherapy of status epilepticus, especially of its later stages, represents an "evidence-free zone," due to a lack of high-quality, controlled trials to inform clinical decisions. This comprehensive narrative review focuses on the pharmacotherapy of SE, presented according to the four-staged approach outlined above, and providing pharmacological properties and efficacy/safety data for each antiepileptic drug according to the strength of scientific evidence from the available literature. Data sources included MEDLINE and back-tracking of references in pertinent studies. Intravenous lorazepam or intramuscular midazolam effectively control early SE in approximately 63-73 % of patients. Despite a suboptimal safety profile, intravenous phenytoin or phenobarbital are widely used treatments for established SE; alternatives include valproate, levetiracetam, and lacosamide. Anesthetics are widely used in refractory and super-refractory SE, despite the current lack of trials in this field. Data on alternative treatments in the later stages are limited. Valproate and levetiracetam represent safe and effective alternatives to phenobarbital and phenytoin for treatment of established SE persisting despite first-line treatment with benzodiazepines. To date there are no class I data to support recommendations for most antiepileptic drugs for established, refractory, and super-refractory SE. Limiting the methodologic heterogeneity across studies is required and high-class randomized, controlled trials to inform clinicians about the best treatment in established and refractory status are needed.

Anesthetic drugs in status epilepticus: risk or rescue? A 6-year cohort study

OBJECTIVE

To evaluate the risks of continuously administered IV anesthetic drugs (IVADs) on the outcome of adult patients with status epilepticus (SE).

METHODS

All intensive care unit patients with SE from 2005 to 2011 at a tertiary academic medical care center were included. Relative risks were calculated for the primary outcome measures of seizure control, Glasgow Outcome Scale score at discharge, and death. Poisson regression models were used to control for possible confounders and to assess effect modification.

RESULTS

Of 171 patients, 37% were treated with IVADs. Mortality was 18%. Patients with anesthetic drugs had more infections during SE (43% vs 11%; p < 0.0001) and a 2.9-fold relative risk for death (2.88; 95% confidence interval 1.45-5.73), independent of possible confounders (i.e., duration and severity of SE, nonanesthetic third-line antiepileptic drugs, and critical medical conditions) and without significant effect modification by different grades of SE severity and etiologies. As IVADs were used after first- and second-line drugs failed, there was a correlation between treatment-refractory SE and the use of IVADs, leading to insignificant results regarding the risk of IVADs and outcome after additional adjustment for refractory SE.

CONCLUSION

Our findings heighten awareness regarding adverse effects of IVADs. Randomized controlled trials are needed to further clarify the association of IVADs with outcome in patients with SE.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that patients with SE receiving IVADs have a higher proportion of infection and an increased risk of death as compared to patients not receiving IVADs.

Problems and controversies in status epilepticus: a review and recommendations

Status epilepticus (SE) is a neurologic emergency that require immediate vigorous treatment in order to prevent serious morbidity or even death. Several investigators have suggested that the underlying etiology is the primary determinant of outcome. We believe that this may be true in aggressively treated SE, but not when the treatment is less than optimal. In this article, we will discuss the factors that have been implicated in affecting SE outcomes, and argue, on the basis of both human and experimental animal data, that aggressive treatment is necessary and appropriate for all presentations of SE in order to maximize the probability of a successful outcome even when the etiology suggests a poor prognosis.

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.