Levetiracetam for Seizure Prophylaxis in Neurocritical Care: A Systematic Review and Meta-analysis

Effectiveness of Fosphenytoin and Levetiracetam to Prevent Posttraumatic Seizures in Young Children with Accidental or Abusive Traumatic Brain Injury

BACKGROUND

Seizures occur frequently in pediatric patients with traumatic brain injury (TBI), particularly abusive head trauma (AHT). There are limited data on the effectiveness of fosphenytoin and levetiracetam to prevent posttraumatic seizures.

METHODS

We performed a retrospective single center cohort study of children < 3 years old admitted with mild [Glasgow Coma Scale (GCS) score 13-15], moderate (GCS 9-12), and severe (GCS 3-8) TBI at a level I trauma center from 2011 to 2021. Antiseizure medications were used at the discretion of the treating physicians. Nonparametric tests were used to compare antiseizure medication prophylaxis and TBI etiology.

RESULTS

A total of 717 patients (263 with AHT, 454 with accidental TBI) were included, of whom 135 (19%) received fosphenytoin, 152 (21%) received levetiracetam, and 430 (60%) did not receive any seizure prophylaxis. Over the study period, the use of fosphenytoin prophylaxis decreased (R2 = 0.67, p = 0.004), whereas the use of levetiracetam increased (R2 = 0.51, p = 0.008). Additionally, the occurrence of early posttraumatic seizures decreased (R2 = 0.58, p = 0.006). Children with AHT were more likely to receive any seizure prophylaxis than those with accidental TBI (52% vs. 27%; p < 0.001) and were more likely to have ≥ 1 seizure during hospitalization (22% vs. 4%; p < 0.001). Among children who received seizure prophylaxis, those who received fosphenytoin had a higher occurrence of seizures than those who received levetiracetam (33% vs.18%; p = 0.004). After controlling for age, admission year, TBI mechanism, and severity of injury, we observed no differences in seizure occurrence between groups.

CONCLUSIONS

In children < 3 years old with TBI, no differences were observed in occurrence of seizures between patients who received fosphenytoin and patients who received levetiracetam prophylaxis after controlling for patient factors including severity of injury. Levetiracetam may be an equally effective alternative to fosphenytoin for seizure prophylaxis for early posttraumatic seizure prevention in this age group.

An update on the novel methods for the discovery of antiseizure and antiepileptogenic medications: where are we in 2024?

INTRODUCTION

Despite the availability of around 30 antiseizure medications, 1/3 of patients with epilepsy fail to become seizure-free upon pharmacological treatment. Available medications provide adequate symptomatic control in two-thirds of patients, but disease-modifying drugs are still scarce. Recently, though, new paradigms have been explored.

AREAS COVERED

Three areas are reviewed in which a high degree of innovation in the search for novel antiseizure and antiepileptogenic medications has been implemented: development of novel screening approaches, search for novel therapeutic targets, and adoption of new drug discovery paradigms aligned with a systems pharmacology perspective.

EXPERT OPINION

In the past, worldwide leaders in epilepsy have reiteratively stated that the lack of progress in the field may be explained by the recurrent use of the same molecular targets and screening procedures to identify novel medications. This landscape has changed recently, as reflected by the new Epilepsy Therapy Screening Program and the introduction of many in vitro and in vivo models that could possibly improve our chances of identifying first-in-class medications that may control drug-resistant epilepsy or modify the course of disease. Other milestones include the study of new molecular targets for disease-modifying drugs and exploration of a systems pharmacology perspective to design new drugs.

Pharmacokinetics of Levetiracetam Seizure Prophylaxis in Severe Traumatic Brain Injury

BACKGROUND

Drug pharmacokinetics (PK) are altered in neurocritically ill patients, and optimal levetiracetam dosing for seizure prophylaxis is unknown.

OBJECTIVE

This study evaluates levetiracetam PK in critically ill patients with severe traumatic brain injury (sTBI) receiving intravenous levetiracetam 1000 mg every 8 (LEV8) to 12 (LEV12) hours for seizure prophylaxis.

METHODS

This prospective, open-label study was conducted at a level 1 trauma, academic, quaternary care center. Patients with sTBI receiving seizure prophylaxis with LEV8 or LEV12 were eligible for enrollment. Five sequential, steady-state, postdose serum levetiracetam concentrations were obtained. Non-compartmental analysis (NCA) and compartmental approaches were employed for estimating pharmacokinetic parameters and projecting steady-state trough concentrations. Pharmacokinetic parameters were compared between LEV8 and LEV12 patients. Monte Carlo simulations (MCS) were performed to determine probability of target trough attainment (PTA) of 6 to 20 mg/L. A secondary analysis evaluated PTA for weight-tiered levetiracetam dosing.

RESULTS

Ten male patients (5 LEV8; 5 LEV12) were included. The NCA-based systemic clearance and elimination half-life were 5.3 ± 1.2 L/h and 4.8 ± 0.64 hours. A one-compartment model provided a higher steady-state trough concentration for the LEV8 group compared with the LEV12 group (13.7 ± 4.3 mg/L vs 6.3 ± 1.7 mg/L; P = 0.008). Monte Carlo simulations predicted regimens of 500 mg every 6 hours, 1000 mg every 8 hours, and 2000 mg every 12 hours achieved therapeutic target attainment. Weight-tiered dosing regimens achieved therapeutic target attainment using a 75 kg breakpoint.

CONCLUSION AND RELEVANCE

Neurocritically ill patients exhibit rapid levetiracetam clearance resulting in a short elimination half-life. Findings of this study suggest regimens of levetiracetam 500 mg every 6 hours, 1000 mg every 8 hours, or 2000 mg every 12 hours may be required for optimal therapeutic target attainment. Patient weight of 75 kg may serve as a breakpoint for weight-guided dosing to optimize levetiracetam therapeutic target attainment for seizure prophylaxis.

Guidelines for Seizure Prophylaxis in Adults Hospitalized with Moderate-Severe Traumatic Brain Injury: A Clinical Practice Guideline for Health Care Professionals from the Neurocritical Care Society

BACKGROUND

There is practice heterogeneity in the use, type, and duration of prophylactic antiseizure medications (ASMs) in patients with moderate-severe traumatic brain injury (TBI).

METHODS

We conducted a systematic review and meta-analysis of articles assessing ASM prophylaxis in adults with moderate-severe TBI (acute radiographic findings and requiring hospitalization). The population, intervention, comparator, and outcome (PICO) questions were as follows: (1) Should ASM versus no ASM be used in patients with moderate-severe TBI and no history of clinical or electrographic seizures? (2) If an ASM is used, should levetiracetam (LEV) or phenytoin/fosphenytoin (PHT/fPHT) be preferentially used? (3) If an ASM is used, should a long versus short (> 7 vs. ≤ 7 days) duration of prophylaxis be used? The main outcomes were early seizure, late seizure, adverse events, mortality, and functional outcomes. We used Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology to generate recommendations.

RESULTS

The initial literature search yielded 1998 articles, of which 33 formed the basis of the recommendations: PICO 1: We did not detect any significant positive or negative effect of ASM compared to no ASM on the outcomes of early seizure, late seizure, adverse events, or mortality. PICO 2: We did not detect any significant positive or negative effect of PHT/fPHT compared to LEV for early seizures or mortality, though point estimates suggest fewer late seizures and fewer adverse events with LEV. PICO 3: There were no significant differences in early or late seizures with longer versus shorter ASM use, though cognitive outcomes and adverse events appear worse with protracted use.

CONCLUSIONS

Based on GRADE criteria, we suggest that ASM or no ASM may be used in patients hospitalized with moderate-severe TBI (weak recommendation, low quality of evidence). If used, we suggest LEV over PHT/fPHT (weak recommendation, very low quality of evidence) for a short duration (≤ 7 days, weak recommendation, low quality of evidence).

Development of SV2A Ligands for Epilepsy Treatment: A Review of Levetiracetam, Brivaracetam, and Padsevonil

Epilepsy is a common neurological disorder that is primarily treated with antiseizure medications (ASMs). Although dozens of ASMs are available in the clinic, approximately 30% of epileptic patients have medically refractory seizures; other limitations in most traditional ASMs include poor tolerability and drug-drug interactions. Therefore, there is an urgent need to develop alternative ASMs. Levetiracetam (LEV) is a first-line ASM that is well tolerated, has promising efficacy, and has little drug-drug interaction. Although it is widely accepted that LEV acts through a unique therapeutic target synaptic vesicle protein (SV) 2A, the molecular basis of its action remains unknown. Even so, the next-generation SV2A ligands against epilepsy based on the structure of LEV have achieved clinical success. This review highlights the research and development (R&D) process of LEV and its analogs, brivaracetam and padsevonil, to provide ideas and experience for the R&D of novel ASMs.

Perioperative management of adults with traumatic brain injury

Despite advances in management strategy, traumatic brain injury remains strongly associated with neurological impairment and mortality. Management of traumatic brain injury requires careful and targeted management of the physiological consequences which extend beyond the scope of the primary impact to the cranium. Here, we present a review of the principles of its acute management in adults. We outline the procedure which patients are assessed and the critical physiological variables which must be monitored to prevent further neurological damage. We describe current interventional strategies from the context of the underlying physiological mechanisms and recent clinical data and identify persisting challenges in traumatic brain injury management and potential avenues of future progress.

Trends of anti-seizure medication prescribing pattern in traumatic brain injury patients for the prevention of posttraumatic seizure in Taiwan

Traumatic brain injury (TBI) patients are recommended to receive anti-seizure medication (ASM) as posttraumatic seizure (PTS) prophylaxis. However, the utilization of ASM, including the prescription patterns and associated clinical characteristics, is limited in Taiwan. Thus, this study aimed to investigate the ASM trends and clinical characteristics. This retrospective cohort study enrolled TBI patients who received levetiracetam, phenytoin, and valproic acid during hospitalization using the National Health Insurance Research Database between 2012 and 2019. The primary outcome was the trend of the ASMs based on the index year. The duration of levetiracetam prescription was categorized as short-term (seven days or less) or long-term (more than seven days). Logistic regression identified the factors associated with long-term usage. A total of 64,461 TBI patients were included. Levetiracetam usage increased yearly, while phenytoin declined. Among the levetiracetam users, 5681 (30.38%) were short-term users, and 13,016 (69.62%) were long-term users. Diagnoses of contusions, intracranial hemorrhage, other intracranial injuries, receiving operations, and a history of cerebrovascular disease were significantly associated with longer duration. Conclusions This study revealed the rising trend of levetiracetam usage, indicating its potential as an alternative to phenytoin. TBI patients with more severe conditions were more likely to receive longer prescriptions.

Optimal Dosing of Levetiracetam for Seizure Prophylaxis in Critically Ill Patients: A Prospective Observational Study

OBJECTIVES

Critically ill patients eliminate levetiracetam (LEV) more rapidly than healthy controls, yet low doses are commonly used for seizure prophylaxis in the ICU setting. We compared the rates of achievement of target serum levels and new onset seizure (clinical and/or electrographic) among patients who received low (500 mg bid) versus high (750-1,000 mg bid) dose LEV.

DESIGN

Prospective, observational study.

SETTING

Tertiary care, academic center.

PATIENTS

We included patients who received prophylactic LEV following traumatic brain injury, intracerebral hemorrhage, spontaneous subarachnoid hemorrhage, or supratentorial neurosurgery between 2019 and 2021. Patients with a history of seizure, antiseizure medication use, or renal failure requiring dialysis were excluded.

INTERVENTIONS

None.

MEASUREMENTS

LEV levels were obtained at steady state. The impact of low-dose versus high-dose LEV on the primary outcome of target LEV levels (12-46 μg/mL), and the secondary outcome of clinical and/or electrographic seizure, were assessed using multivariable logistic regression analyses adjusting for age, LEV loading dose, BMI, primary diagnosis and creatinine clearance (CrCl).

MAIN RESULTS

Of the 205 subjects included in analyses, n = 106 (52%) received LEV 500 mg bid (median 13 mg/kg/d), and n = 99 (48%) received LEV 750-1,000 mg bid (median 25 mg/kg/d). Overall, 111 of 205 patients (54%) achieved target levels: 48 (45%) from the low-dose group versus 63 (64%) from the high-dose group (odds ratio [OR] 2.1; 95% CI, 1.1-3.7; p = 0.009). In multivariable analyses, high-dose LEV predicted target levels (adjusted OR [aOR] 2.23; 95% CI, 1.16-4.27; p = 0.016), and was associated with lower seizure odds (aOR 0.32; 95% CI, 0.13-0.82; p = 0.018) after adjusting for age, loading dose, BMI, diagnosis, and CrCl.

CONCLUSIONS

Underdosing of LEV was common, with only 54% of patients achieving target serum levels. Higher doses (750-1,000 mg bid) were more than twice as likely to lead to optimal drug levels and reduced the odds of seizure by 68% compared with low-dose regimens (500 mg bid).

Seizure Prophylaxis in Young Patients Following Traumatic Brain Injury

Introduction

Phenytoin is one of the commonly used anti.seizure medications in nontraumatic seizures. However, its utility and safety in young patients with traumatic brain injury (TBI) for the prevention of early-onset seizures (EOS) are debatable. We sought to explore the use of phenytoin as a seizure prophylaxis following TBI. We hypothesized that administering phenytoin is not effective in preventing EOS after TBI.

Methods

This was a retrospective observational study conducted on adult TBI patients. EOS was defined as a witnessed seizure within a week postinjury. Data were compared as phenytoin versus no-phenytoin use, EOS versus no-EOS, and among TBI severity groups.

Results

During 1 year, 639 TBI patients were included with a mean age of 32 years; of them, 183 received phenytoin as seizure prophylaxis, and 453 received no prophylaxis medication. EOS was documented in 13 (2.0%) patients who received phenytoin, and none had EOS among the nonphenytoin group. The phenytoin group was more likely to have a higher Marshall Score (P = 0.001), lower Glasgow Coma Scale (GCS) (P = 0.001), EOS (P = 0.001), and higher mortality (P = 0.001). Phenytoin was administrated for 15.2%, 43.2%, and 64.5% of mild, moderate, and severe TBI patients, respectively. EOS and no-EOS groups were comparable for age, gender, mechanism of injury, GCS, Marshall Score, serum phenytoin levels, liver function levels, hospital stay, and mortality. Multivariable logistic regression analysis showed that low serum albumin (odds ratio [OR] 0.81; 95% confidence interval [CI] 0.676.0.962) and toxic phenytoin level (OR 43; 95% CI 2.420.780.7) were independent predictors of EOS.

Conclusions

In this study, the prophylactic use of phenytoin in TBI was ineffective in preventing EOS. Large-scale matched studies and well-defined hospital protocols are needed for the proper utility of phenytoin post-TBI.

Modified CAVE score for predicting late seizures after intracerebral hemorrhage

BACKGROUND AND PURPOSE

Seizures commonly occur in patients with intracerebral hemorrhage (ICH). Anticonvulsants are commonly used for preventing seizures in patients with ICH. Thus, patients with ICH at high risk of seizures must be identified. The study aims to elucidate whether double the score of cortex involvement in ICH patients can increase accuracy of CAVE score for predicting late seizures.

METHOD

This retrospective analysis of the medical records of surviving patients admitted between June 1, 2013, and December 31, 2019. Validated the CAVE score and modified it (CAVE2). The main outcome of patients with ICH was seizures. The first seizures occurring within 7 days after a stroke were defined as early seizures. Seizures occurring after 1 week of stroke onset, including patients who had experienced early seizures or patients who had not, were defined as late seizures. CAVE and CAVE2 scores were validated using the cohort. The accuracy and discrimination of those two scores were accessed by the area under the operating characteristic curve. Akaike information criterion, integrated discrimination improvement, and continuous net reclassification improvement were used to assess the performance of the CAVE and CAVE2 scores.

RESULTS

In the cohort showed that late seizures occurred in 12.7% (52/408) of patients with ICH. Male sex, age > 65 years, cortex involvement, and early seizures were associated with the occurrence of late seizures, with odds ratios of 2.09, 2.04, 4.12, and 3.78, respectively. The risk rate of late seizures was 6.66% (17/255), 14.8% (17/115), and 47.4% (18/38) for CAVE scores ≤ 1, 2, and ≥ 3, and 4.6% (12/258), 18.3% (13/71), and 54.4 (20/37) for CAVE2 scores ≤ 1, 2, and ≥ 3 respectively. The C-statistics for the CAVE and CAVE2 scores were 0.73 and 0.74 respectively.

CONCLUSION

The CAVE score can identify patients with ICH and high risk for late seizures. The CAVE can be modified by changing the score of cortex involvement to 2 points to improve accuracy in predicting late seizures in patients with ICH.

Personalized antiseizure medication therapy in critically ill adult patients

Precision medicine has the potential to have a significant impact on both drug development and patient care. It is crucial to not only provide prompt effective antiseizure treatment for critically ill patients after seizures start but also have a proactive mindset and concentrate on epileptogenesis and the underlying cause of the seizures or seizure disorders. Critical illness presents different treatment issues compared with the ambulatory population, which makes it challenging to choose the best antiseizure medications and to administer them at the right time and at the right dose. Since there is a paucity of information available on antiseizure medication dosing in critically ill patients, therapeutic drug monitoring is a useful tool for defining each patient's personal therapeutic range and assisting clinicians in decision-making. Use of pharmacogenomic information relating to pharmacokinetics, hepatic metabolism, and seizure etiology may improve safety and efficacy by individualizing therapy. Studies evaluating the clinical implementation of pharmacogenomic information at the point-of-care and identification of biomarkers are also needed. These studies may make it possible to avoid adverse drug reactions, maximize drug efficacy, reduce drug-drug interactions, and optimize medications for each individual patient. This review will discuss the available literature and provide future insights on precision medicine use with antiseizure therapy in critically ill adult patients.

Levetiracetam dosing for seizure prophylaxis in neurocritical care patients

BACKGROUND/OBJECTIVE

Levetiracetam is used for seizure prophylaxis in patients presenting with subarachnoid hemorrhage (SAH) or traumatic brain injury (TBI). We aim to characterize the optimal levetiracetam dosage for seizure prophylaxis.

METHODS

This retrospective cohort study included adult patients at an academic tertiary hospital presenting with SAH or TBI who received levetiracetam at a total daily dose (TDD) equivalent to or greater than 1000 mg. The primary outcome was combined seizure incidence, including clinical and subclinical seizures.

RESULTS

We identified 139 patients (49.6% male, mean age 53 years) for inclusion. For patients receiving a 1000-mg TDD, the administration was 500 mg twice daily. For patients receiving >1000-mg TDD, 77/78 patients received 1000 mg twice daily and one patient received 750 mg twice daily. Patients receiving 1000-mg TDD had a higher seizure incidence than those receiving >1000-mg TDD (p = 0.01), despite no difference in examined confounders, including history of alcoholism (p = 0.49), benzodiazepine use (p = 0.28), or propofol use (p = 0.17). No difference in adverse effects was observed (anemia, p = 0.44; leukopenia, p = 0.60; thrombocytopenia, p = 0.86).

CONCLUSIONS

Patients may experience a reduced incidence of clinical and electroencephalographic seizures with levetiracetam dosing >1000-mg TDD.

Levetiracetam, from broad-spectrum use to precision prescription: A narrative review and expert opinion

Levetiracetam (LEV) is an antiseizure medication (ASM) whose mechanism of action involves the modulation of neurotransmitters release through binding to the synaptic vesicle glycoprotein 2A. It is a broad-spectrum ASM displaying favorable pharmacokinetic and tolerability profiles. Since its introduction in 1999, it has been widely prescribed, becoming the first-line treatment for numerous epilepsy syndromes and clinical scenarios. However, this might have resulted in overuse. Increasing evidence, including the recently published SANAD II trials, suggests that other ASMs are reasonable therapeutic options for generalized and focal epilepsies. Not infrequently, these ASMs show better safety and effectiveness profiles compared to LEV (partially due to the latter's well-known cognitive and behavioral adverse effects, present in up to 20% of patients). Moreover, it has been shown that the underlying etiology of epilepsy is significantly linked to ASMs response in particular scenarios, highlighting the importance of an etiology-based ASM choice. In the case of LEV, it has demonstrated an optimal effectiveness in Alzheimer's disease, Down syndrome, and PCDH19-related epilepsies whereas, in other etiologies such as malformations of cortical development, it may show negligible effects. This narrative review analyzes the current evidence related to the use of LEV for the treatment of seizures. Illustrative clinical scenarios and practical decision-making approaches are also addressed, therefore aiming to define a rational use of this ASM.

Management of traumatic brain injury in the non-neurosurgical intensive care unit: a narrative review of current evidence

Each year, approximately 70 million people suffer traumatic brain injury, which has a significant physical, psychosocial and economic impact for patients and their families. It is recommended in the UK that all patients with traumatic brain injury and a Glasgow coma scale ≤ 8 should be transferred to a neurosurgical centre. However, many patients, especially those in whom neurosurgery is not required, are not treated in, nor transferred to, a neurosurgical centre. This review aims to provide clinicians who work in non-neurosurgical centres with a summary of contemporary studies relevant to the critical care management of patients with traumatic brain injury. A targeted literature review was undertaken that included guidelines, systematic reviews, meta-analyses, clinical trials and randomised controlled trials (published in English between 1 January 2017 and 1 July 2022). Studies involving key clinical management strategies published before this time, but which have not been updated or repeated, were also eligible for inclusion. Analysis of the topics identified during the review was then summarised. These included: fundamental critical care management approaches (including ventilation strategies, fluid management, seizure control and osmotherapy); use of processed electroencephalogram monitoring; non-invasive assessment of intracranial pressure; prognostication; and rehabilitation techniques. Through this process, we have formulated practical recommendations to guide clinical practice in non-specialist centres.

Predictive factors for post operative seizures following meningioma resection in patients without preoperative seizures: a multicenter retrospective analysis

PURPOSE

Meningiomas are the most common primary brain tumor and represent 35% of all intracranial neoplasms. However, in the early post-operative period approximate 3-5% of patients experience an acute symptomatic seizure. Establishing risk factors for postoperative seizures will identify those patients without preoperative seizures at greatest risk of postoperative seizures and may guide antiseizure medications (ASMs) management.

METHODS

Adult seizure naïve patients who underwent primary resection of a World Health Organization (WHO) Grade 1-3 meningioma at the three Mayo Clinic Campuses between 2012-2022 were retrospectively reviewed. Multivariate regression analyses were used to identify radiological, surgical, and management features with the development of new-onset seizures in patients undergoing meningioma resection.

RESULTS

Of 113 seizure naïve patients undergoing meningioma resection 11 (9.7%) experienced a new-onset post-operative seizure. Tumor volume ≥ 25 cm³ (Odds Ratio (OR) 5.223, 95% Confidence Interval (CI) 1.546 - 17.650, p = 0.008) and cerebral convexity meningiomas (OR 4.742, 95% CI 1.255 - 14.336, p = 0.016) were most associated with new onset postoperative seizures in multivariate analysis. ASMs and corticosteroid therapies did not display a significant difference among those with and without a new onset postoperative seizure.

CONCLUSION

In the current study, a larger tumor volume (≥ 25 cm³) and/or convexity meningiomas predicted the development of new onset post-operative seizures. Those who present with these factors should be counseled for their increased risk of new onset post-operative seizures and may benefit from prophylactic ASMs therapy.

Impact of seizures and their prophylaxis with antiepileptic drugs on rehabilitation course of patients with traumatic or hemorrhagic brain injury

Objective

To determine whether, in patients undergoing rehabilitation after traumatic or hemorrhagic brain injury, seizures and the use of antiepileptic drugs (AEDs) negatively impact on functional outcome, and, in turn, whether prophylactic AED therapy can prevent the development of seizures.

Design

Observational retrospective study.

Setting

Highly specialized inpatient neurorehabilitation clinic.

Participants

Patients with traumatic brain injury (TBI), or hemorrhagic stroke (HS) consecutively admitted to our neurorehabilitation unit between January 1, 2009, and December 31, 2018.

Main measures and variables

Patients' demographic data, neurological status (Glasgow Coma Scale), and rehabilitation outcome (Functional Independence Measure scale), both assessed on admission and on discharge, associated neurosurgical procedures (craniectomy, or cranioplasty), AED use, early or late seizures occurrence, and death during hospitalization.

Results

Of 740 patients, 162 (21.9%) had seizures, and prophylactic AEDs were started in 192 (25.9%). Multivariate logistic regression identified severity of brain injury as a risk factor for acute symptomatic seizures (ASS) in HS (OR = 1.800, 95%CI = 1.133–1.859, p = 0.013), and for unprovoked seizures (US) in TBI (OR = 1.679, 95%CI = 1.062–2.655, p = 0.027). Prophylaxis with AEDs reduced ASS frequency, but, if protracted for months, was associated with US occurrence (HS, p &lt; 0.0001; TBI, p = 0.0002; vs. untreated patients). Presence of US (β = −0.12; p &lt; 0.0001) and prophylaxis with AEDs (β = −0.09; p = 0.002), were associated with poor functional outcome, regardless of age, severity of brain insult, and HS vs. TBI subtype.

Conclusions

Severity of brain injury and occurrence of seizures during neurorehabilitation are the main driver of poor outcome in both HS and TBI. The possible detrimental role on the epileptogenic and functional outcome played by seizures prophylaxis with AEDs, nonetheless useful to prevent ASS if administered over the first week after the brain injury, warrants further investigation.

Initial neurocritical care of severe traumatic brain injury: New paradigms and old challenges

Background:

Early neurocritical care aims to ameliorate secondary traumatic brain injury (TBI) and improve neural salvage. Increased engagement of neurosurgeons in neurocritical care is warranted as daily briefings between the intensivist and the neurosurgeon are considered a quality indicator for TBI care. Hence, neurosurgeons should be aware of the latest evidence in the neurocritical care of severe TBI (sTBI).

Methods:

We conducted a narrative literature review of bibliographic databases (PubMed and Scopus) to examine recent research of sTBI.

Results:

This review has several take-away messages. The concept of critical neuroworsening and its possible causes is discussed. Static thresholds of intracranial pressure (ICP) and cerebral perfusion pressure may not be optimal for all patients. The use of dynamic cerebrovascular reactivity indices such as the pressure reactivity index can facilitate individualized treatment decisions. The use of ICP monitoring to tailor treatment of intracranial hypertension (IHT) is not routinely feasible. Different guidelines have been formulated for different scenarios. Accordingly, we propose an integrated algorithm for ICP management in sTBI patients in different resource settings. Although hyperosmolar therapy and decompressive craniectomy are standard treatments for IHT, there is a lack high-quality evidence on how to use them. A discussion of the advantages and disadvantages of invasive ICP monitoring is included in the study. Addition of beta-blocker, anti-seizure, and anticoagulant medications to standardized management protocols (SMPs) should be considered with careful patient selection.

Conclusion:

Despite consolidated research efforts in the refinement of SMPs, there are still many unanswered questions and novel research opportunities for sTBI care.

Pharmacokinetic considerations surrounding the use of levetiracetam for seizure prophylaxis in neurocritical care - an overview

INTRODUCTION

Levetiracetam (LEV) is one of the most widely used anti-seizure medications (ASMs) in clinical practice. This is due both to a different mechanism of action when compared to other ASMs and its easy handling. Indeed, because of its interesting pharmacokinetic properties, it is often used outside of the labelled indications, notably in the neurocritical setting as prophylaxis of epileptic seizures.

AREAS COVERED

A literature search was conducted and the most relevant studies on the pharmacokinetic properties of LEV were selected by two independent investigators. Current evidence on the use of ASM prophylaxis in the neurocritical setting was also reviewed, highlighting and discussing the strengths and limits of LEV as drug of choice for anti-epileptic prophylaxis in this scenario.

EXPERT OPINION

LEV has a "near-ideal" pharmacokinetic profile, which makes it an attractive drug for ASM prophylaxis in neurocritical care. However, current recommendations restrict ASMs prophylaxis to very selected circumstances and the role of LEV is marginal. Moreover, studies are generally designed to compare LEV versus phenytoin, whereas studies comparing LEV versus placebo are lacking. Further randomized trials will be needed to better elucidate LEV utility and its neuroprotective role in the neurocritical setting.

Optimization of levetiracetam dosing regimen in critically ill patients with augmented renal clearance: a Monte Carlo simulation study

Background

Levetiracetam pharmacokinetics is extensively altered in critically ill patients with augmented renal clearance (ARC). Consequently, the dosage regimens commonly used in clinical practice may not be sufficient to achieve target plasma concentrations. The aim of this study is to propose alternative dosage regimens able to achieve target concentrations in this population. Furthermore, the feasibility of the proposed dosing regimens will be discussed from a clinical point of view.

Methods

Different dosage regimens for levetiracetam were evaluated in critically ill patients with ARC. Monte Carlo simulations were conducted with extended or continuous infusions and/or high drug doses using a previously developed population pharmacokinetic model. To assess the clinical feasibility of the proposed dosages, we carried out a literature search to evaluate the information on toxicity and efficacy of continuous administration or high doses, as well as the post-dilution stability of levetiracetam.

Results

According to the simulations, target concentrations in patients with CrCl of 160 or 200 mL/min can be achieved with the 3000 mg daily dose by prolonging the infusion time of levetiracetam. For patients with CrCl of 240 mL/min, it would be necessary to administer doses higher than the maximum recommended. Available evidence suggests that levetiracetam administration in continuous infusion or at higher doses than those approved seems to be safe. It would be desirable to re-examinate the current recommendations about drug stability and to achieve a consensus in this issue.

Conclusions

Conventional dosage regimens of levetiracetam (500–1500 mg twice daily in a short infusion) do not allow obtaining drug plasma concentrations among the defined target in critically ill patients with ARC. Therefore, new dosing guidelines with specific recommendations for patients in this subpopulation are needed. This study proposes new dosages for levetiracetam, including extended (4 or 6 h) infusions, continuous infusions or the administration of doses higher than the recommended in the summary of product characteristics (> 3000 mg). These new dosage recommendations take into account biopharmaceutical and pharmacokinetic aspects and meet feasibility criteria, which allow them to be transferred to the clinical environment with safety and efficacy. Nevertheless, further clinical studies are needed to confirm these results.

Levetiracetam Mechanisms of Action: From Molecules to Systems

Epilepsy is a chronic disease that affects millions of people worldwide. Antiepileptic drugs (AEDs) are used to control seizures. Even though parts of their mechanisms of action are known, there are still components that need to be studied. Therefore, the search for novel drugs, new molecular targets, and a better understanding of the mechanisms of action of existing drugs is still crucial. Levetiracetam (LEV) is an AED that has been shown to be effective in seizure control and is well-tolerable, with a novel mechanism of action through an interaction with the synaptic vesicle protein 2A (SV2A). Moreover, LEV has other molecular targets that involve calcium homeostasis, the GABAergic system, and AMPA receptors among others, that might be integrated into a single mechanism of action that could explain the antiepileptogenic, anti-inflammatory, neuroprotective, and antioxidant properties of LEV. This puts it as a possible multitarget drug with clinical applications other than for epilepsy. According to the above, the objective of this work was to carry out a comprehensive and integrative review of LEV in relation to its clinical uses, structural properties, therapeutical targets, and different molecular, genetic, and systemic action mechanisms in order to consider LEV as a candidate for drug repurposing.