Management of Seizures in the Critically Ill

Differential association of subtypes of epileptiform activity with outcome after cardiac arrest

BACKGROUND

Epileptiform activity is common after cardiac arrest, although intensity of electroencephalographic (EEG) monitoring may affect detection rates. Prior work has grouped these patterns together as "malignant," without considering discrete subtypes. We describe the incidence of distinct patterns in the ictal-interictal spectrum at two centers and their association with outcomes.

METHODS

We analyzed a retrospective cohort of comatose post-arrest patients admitted at two academic centers from January 2011 to October 2014. One center uses routine continuous EEG, the other acquires "spot" EEG at the treating physicians' discretion. We reviewed all available EEG data and classified epileptiform patterns. We abstracted antiepileptic drugs (AEDs) administrations from the electronic medical record. We compared apparent incidence of each pattern between centers, and compared outcomes (awakening from coma, survival to discharge, discharge modified Rankin Scale (mRS) 0-2) across EEG patterns and number of AEDs administered.

RESULTS

We included 818 patients. Routine continuous EEG was associated with a higher apparent incidence of polyspike burst-suppression (25% vs 13% P < 0.001). Frequency of other epileptiform findings did not differ. Among patients with any epileptiform pattern, only 2/258 (1%, 95%CI 0-3%) were discharged with mRS 0-2, although 24/258 (9%, 95%CI 6-14%) awakened and 36/258 (14%, 95%CI 10-19%) survived. The proportions that awakened and survived decreased in a stepwise manner with progressively worse EEG patterns (range 38% to 2% and 32% to 7%, respectively). Among patients receiving ≥3 AEDs, only 5/80 (6%, 95%CI 2-14%) awakened and 1/80 (1%, 95%CI 0-7%) had a mRS 0-2.

CONCLUSION

We found high rates of epileptiform EEG findings, regardless of intensity of EEG monitoring. The association of distinct ictal-interictal EEG findings with outcome was variable.

Intravenous levetiracetam in critically ill children

Background:

To report the effectiveness and safety of intravenous (IV) levetiracetam (LEV) in the treatment of critically ill children with acute repetitive seizures and status epilepticus (SE) in a children's hospital.

Materials and Methods:

We retrospectively analyzed data from children treated with IV LEV.

Results:

The mean age of the 108 children was 69.39 ± 46.14 months (1-192 months). There were 58 (53.1%) males and 50 (46.8%) females. LEV load dose was 28.33 ± 4.60 mg/kg/dose (10-40 mg/kg). Out of these 108 patients, LEV terminated seizures in 79 (73.1%). No serious adverse effects were observed but agitation and aggression were developed in two patients, and mild erythematous rash and urticaria developed in one patient.

Conclusion:

Antiepileptic treatment of critically ill children with IV LEV seems to be effective and safe. Further study is needed to elucidate the role of IV LEV in critically ill children.

Seizures and anticonvulsants after aneurysmal subarachnoid hemorrhage

Seizures and seizure-like activity may occur in patients experiencing aneurysmal subarachnoid hemorrhage. Treatment of these events with prophylactic antiepileptic drugs remains controversial. An electronic literature search was conducted for English language articles describing the incidence and treatment of seizures after aneurysmal subarachnoid hemorrhage from 1980 to October 2010. A total of 56 articles were included in this review. Seizures often occur at the time of initial presentation or aneurysmal rebleeding before aneurysm treatment. Seizures occur in about 2% of patients after invasive aneurysm treatment, with a higher incidence after surgical clipping compared with endovascular repair. Non-convulsive seizures should be considered in patients with poor neurological status or deterioration. Seizure prophylaxis with antiepileptic drugs is controversial, with limited data available for developing recommendations. While antiepileptic drug use has been linked to worse prognosis, studies have evaluated treatment with almost exclusively phenytoin. When prophylaxis is used, 3-day treatment seems to provide similar seizure prevention with better outcome compared with longer-term treatment.

Levetiracetam compared to valproic acid: plasma concentration levels, adverse effects and interactions in aneurysmal subarachnoid hemorrhage

OBJECTIVE

Both valproic acid and levetiracetam are anti-epileptic drugs, often used either alone or in combination. The present study compares valproate (VPA) with levetiracetam (LEV) as an intravenous (i.v.) anticonvulsant treatment in intensive care patients suffering from aneurysmal subarachnoid hemorrhage (aSAH) with a high risk of seizures.

PATIENTS AND METHODS

A prospective, single-center patient registry of 35 intensive care unit (ICU) patients with onset seizure and/or high risk of seizures underwent an anticonvulsive, first-line single treatment regimen either with VPA or LEV. Plasma concentrations (pc), interactions between drugs in the ICU context, adverse effects and seizure occurrences were observed and recorded.

RESULTS

A significant decrease in the pc in patients treated with LEV was observed after changing from intravenous (160±51μmol/l) to enteral liquid application (113±58μmol/l), corresponding to a 70.3% bioavailability for enteral liquid applications. The pc in VPA patients decreased significantly, from (491±138μmol/l) to (141±50μmol/l), after adding meropenem to the therapy (p<0.05). Three epileptic seizures occurred during anticonvulsive therapy in the LEV group, and two in the VPA group, including one non-convulsive status epilepticus (NCSE).

CONCLUSION

Though this finding needs further verification, the enteral liquid application of levetiracetam seems to be associated with lower bioavailability than the common oral application of levetiracetam. The use of the antibiotic drug meropenem together with valproic acid leads to lower pc levels in patients treated with of valproic acid. For clinical practice, this indicates the need to monitor the levels of valproic acid in combination with meropenem.

Genetic predisposition to adverse drug reactions in the intensive care unit

Adverse drug reactions are a significant public health problem that leads to mortality, hospital admissions, an increased length of stay, increasing healthcare costs, and withdrawal of drugs from market. Intensive care unit patients are particularly vulnerable and are at an elevated risk. Critical care practitioners, regulatory agencies, and the pharmaceutical industry aggressively seek biomarkers to mitigate patient risk. The rapidly expanding field of pharmacogenomics focuses on the genetic contributions to the variability in drug response. Polymorphisms may explain why some groups of patients have the expected response to pharmacotherapy whereas others experience adverse drug reactions. Historically, genetic association studies have focused on characterizing the effects of variation in drug metabolizing enzymes on pharmacokinetics. Recent work has investigated drug transporters and the variants of genes encoding drug targets, both intended and unintended, that comprise pharmacodynamics. This has led to an appreciation of the role that genetics plays in adverse drug reactions that are either predictable extensions of a drug's known therapeutic effect or idiosyncratic.This review presents the evidence for a genetic predisposition to adverse drug reactions, focusing on gene variants producing alterations in drug pharmacokinetics and pharmacodynamics in intensive care unit patients. Genetic biomarkers with the strongest associations to adverse drug reaction risk in the intensive care unit are presented along with the medications involved. Variant genotypes and phenotypes, allelic frequencies in different populations, and clinical studies are discussed. The article also presents the current recommendations for pharmacogenetic testing in clinical practice and explores the drug, patient, research study design, regulatory, and practical issues that presently limit more widespread implementation.

How I treat status epilepticus in the Neuro-ICU

Status epilepticus still remains a formidable adversary to neurointensivists. Although the majority of cases admitted to the Neuro-ICU are easily controlled with one or two antiepileptic drug defense lines, several cases become refractory and end up receiving general anesthetics for days or weeks with significant morbidity. Treatment algorithms have been published and should be followed, but in many cases they are inadequate because, especially in the distal branches of the treatment tree, are based on anecdotal data or small series of patients. In addition, a double-blind, randomized-controlled study in status has not been done for many years and solid data are lacking for the newer antiepileptics. Therefore, in the moderately to severely refractory cases, status treatment is based on personal previous experience and becomes an art more than a science. In this review of a difficult case, we discuss some fine details of the treatment provided and emphasize the multidisciplinary approach that should be followed including involvement of neurointensivists, epileptologists, electroencephalographers, and neurosurgeons.

Intravenous levetiracetam: treatment experience with the first 50 critically ill patients

Levetiracetam (LEV) is a broad-spectrum antiepileptic drug with no known interactions and a favorable profile of adverse events. These properties make it a good candidate for use in critically ill patients. An intravenous formulation of LEV was recently approved. The present study retrospectively assesses the safety and efficacy of LEV in the first 50 critically ill patients treated with intravenous LEV. Indications for use were seizure prophylaxis, acute symptomatic seizures, and all forms of status epilepticus. There were no major adverse effects, although less prominent changes may have been masked by the already severely compromised condition of these patients. Two patients (4%) had transiently lowered platelet counts (55,000 and 82,000, respectively). Efficacy, defined as cessation of seizure activity or prevention of its recurrence, was observed in 41 of 50 patients (82%). Antiepileptic treatment of critically ill patients with LEV seems to be effective and safe according to the data for this small cohort, but this observation warrants further prospective investigation in a larger number of patients.

Seizures and status epilepticus in the critically ill

Seizures represent stereotypic electroencephalographic (EEG) and behavioral paroxysms as a consequence of electrical neurologic derangement. Seizures are usually described as focal or generalized motor convulsions; however, nonconvulsive seizures that occur in the absence of motor activity may escape clinical detection. Because of the admission diagnoses and dramatic physiologic and metabolic derangements common to critically ill patients, the entire spectrum of seizure disorders may be encountered in the ICU. Seizures in the ICU are attributable to primary neurologic pathology or secondary to critical illness and clinical management. For optimal treatment, early diagnosis of the seizure type and its cause is important to ensure appropriate therapy. Convulsive status epilepticus requires emergent treatment before irreversible brain injury and severe metabolic disturbances occur.

Anesthetic considerations for intraoperative management of cerebrovascular disease in neurovascular surgical procedures

Despite new surgical methods and interventions a considerable number of patients who undergo neurovascular procedures emergently or electively have substantial mortality, morbidity, and disability. Sound knowledge of pathophysiology of cerebral hypoperfusion, reliable and timely information from monitoring devices, and appropriate choice of therapeutic intervention is essential for successful anesthetic management of these patients. The management of perioperative vasospasm and temporary ischemia during aneurysm clipping require an understanding of cerebral vascular pathophysiology and neuroprotective measures.