A comparison of phenytoin-loading techniques in the emergency department

Levetiracetam vs. Fosphenytoin for Second-Line Treatment of Status Epilepticus: Propensity Score Matching Analysis Using a Nationwide Inpatient Database

Objective: Status epilepticus is a major emergency condition. The choice of antiepileptic drugs for second-line treatment after benzodiazepine remains controversial, including levetiracetam vs. fosphenytoin. We compare the safety of intravenous levetiracetam and fosphenytoin as a second-line treatment in patients with status epilepticus using a nationwide database.

Methods: An observational study conducted with the Japanese Diagnosis Procedure Combination inpatient database identified adult patients who had been admitted for status epilepticus and who had received intravenous diazepam on the day of admission from March 1, 2011 to March 31, 2018. Patients who received intravenous levetiracetam on the day of admission were defined as the levetiracetam group and those who received intravenous fosphenytoin on the day of admission were defined as the fosphenytoin group. Propensity score matching was performed to compare outcomes obtained for the levetiracetam and fosphenytoin groups.

Results: The analysis examined data of 5,667 patients. Overall, 1,403 (25%) patients received levetiracetam; 4,264 (75%) received fosphenytoin. One-to-one propensity score matching created 1,363 matched pairs. No significant difference was found in in-hospital mortality (5.2 vs. 5.1%; odds ratio, 1.03; 95% confidence interval, 0.73–1.46). The proportion of vasopressor use on the day of admission was significantly lower for the levetiracetam group than for the fosphenytoin group (3.2 vs. 4.9%; odds ratio, 0.63; 95% confidence interval, 0.43–0.92). No significant difference was found in other secondary outcomes including total hospitalization cost.

Conclusion: Levetiracetam was related to significantly reduced vasopressor use on the day of admission than that found for fosphenytoin, in adult status epilepticus.

Changes in Real-world Practice Patterns of Antiepileptic Drugs for Status Epilepticus: A Nationwide Observational Study in Japan

Intravenous (i.v.) phenytoin/fosphenytoin is recommended as the second-line therapy of antiepileptic drugs in patients with status epilepticus (SE). i.v. Levetiracetam is regarded as an effective and safe equivalent with i.v. phenytoin/fosphenytoin. However, i.v. levetiracetam is not covered by public health insurance for SE in most countries. For this study, we performed the real-world practice pattern survey of antiepileptic drugs for status epilepticus using the nationwide inpatient database. We used the Japanese Diagnosis Procedure Combination inpatient database in Japan and identified all cases of emergency admission attributable to status epilepticus from March 2011 through March 2018. We described the patient characteristics and practice pattern of antiepileptic drugs. The analysis conducted for this study examined 31,472 cases. As the second-line therapy, the use of i.v. levetiracetam increased rapidly from 2016; 35% of cases received i.v. levetiracetam in 2017. By contrast, the use of i.v. phenytoin/fosphenytoin decreased from 2016. In-hospital mortality decreased year-by-year. No year-by-year change was observed for deaths within 24 h, length of hospital stay, drug-induced hepatitis, or drug-induced eruption. Although the use of levetiracetam for treatment of SE is not compensated by public health insurance in Japan, i.v. levetiracetam use is increasing dramatically as the second-line SE therapy. We propose that health insurance coverage be extended to include i.v. levetiracetam treatment for SE.

Efficacy of levetiracetam versus fosphenytoin for the recurrence of seizures after status epilepticus

Benzodiazepines are used as first-line treatments for status epilepticus. Fosphenytoin (FPHT) is recommended for second-line therapy; however, intravenous injection of levetiracetam (LEV) may also be effective against status epilepticus. Herein, we compared the efficacy and safety of LEV as a second-line treatment for status epilepticus with FPHT in Japanese patients.Patients with status epilepticus were selected from the database of the Emergency and Critical Care Center of Hitachi General Hospital. The subjects were patients whose status epilepticus was successfully stopped by diazepam, and in whom FPHT or LEV was administered after diazepam. As LEV injections recently became clinically available in Japan, the choice of drug was determined by the treatment period. Thus, 21 patients who were intravenously injected with LEV as a second-line therapy and 42 matched patients (historical controls) who were treated with FPHT (1:2) were selected.The subjects had a mean age of 64.0 ± 2.2 years, and included 48 males and 15 females. The status epilepticus control rates of the FPHT and LEV groups did not differ significantly (81.0% [34/42] vs 85.1% [18/21], respectively; P  =  .69). As for serious adverse events, a reduction in blood pressure was observed in the FPHT group, but not in the LEV group. The oral anticonvulsant switching rates of the 2 groups were similar, but the same-drug switching rates of the FPHT and LEV groups were 8.1% and 77.8%, respectively.The efficacy of intravenous LEV injections after status epilepticus was equivalent to that of FPHT, and the incidence of adverse events was lower in the LEV group. LEV is effective and safe at preventing recurrent seizures after status epilepticus following benzodiazepine treatment.

Status Epilepticus and Beyond: A Clinical Review of Status Epilepticus and an Update on Current Management Strategies in Super-refractory Status Epilepticus

Status epilepticus and refractory status epilepticus represent some of the most complex conditions encountered in the neurological intensive care unit. Challenges in management are common as treatment options become limited and prolonged hospital courses are accompanied by complications and worsening patient outcomes. Antiepileptic drug treatments have become increasingly complex. Rational polytherapy should consider the pharmacodynamics and kinetics of medications. When seizures cannot be controlled with medical therapy, alternative treatments, including early surgical evaluation can be considered; however, evidence is limited. This review provides a brief overview of status epilepticus, and a recent update on the management of refractory status epilepticus based on evidence from the literature, evidence-based guidelines, and experiences at our institution.

Predictors of Outcome in Children with Status Epilepticus during Resuscitation in Pediatric Emergency Department: A Retrospective Observational Study

Objectives:

To study the clinical profile and predictors of outcome in children with status epilepticus (SE) during resuscitation in pediatric emergency department.

Materials and Methods:

This retrospective study was carried out in a tertiary care teaching hospital. Admission and resuscitation data of children, aged between 1 month and 12 years, treated for SE, between September 2013 and August 2014, were extracted using a standard data collection form. Our SE management protocol had employed a modified pediatric assessment triangle to recognize and treat acute respiratory failure, cardiovascular dysfunction (CD), and subtle SE until all parameters resolved. Continuous positive airway pressure, fluid boluses based on shock etiology, inotropes, and cardiac safe anticonvulsants were the other modifications. Risk factors predicting mortality during resuscitation were analyzed using univariate and penalized logistic regression.

Results:

Among 610 who were enrolled, 582 (95.4%) survived and 28 (4.6%) succumbed. Grunt odds ratio (OR): 3.747 (95% confidence interval [CI]: 1.035−13.560), retractions OR: 2.429 (95% CI: 1.036−5.698), rales OR: 10.145 (95% CI: 4.027−25.560), prolonged capillary refill time OR: 3.352 (95% CI: 1.339−8.388), and shock requiring >60 mL/kg fluids OR: 2.439 (95% CI 1.040−5.721) were associated with 2−3 times rise in mortality. Inappropriate prehospital treatment and CD were the significant predictors of mortality OR: 7.82 (95% CI 2.10−29.06) and 738.71 (95% CI: 97.11−999), respectively. Resolution of CD was associated with improved survival OR: 0.02 (95% CI: 0.003−0.17).

Conclusion:

Appropriate prehospital management and treatment protocol targeting resolution of CD during resuscitation could reduce mortality in children with SE.

IV fosphenytoin in obese patients: Dosing strategies, safety, and efficacy

Background

Previous studies evaluated the disposition of IV phenytoin loading doses and found that obese patients had increased drug distribution into excess body weight, larger volumes of distribution, and longer half-lives when compared to their nonobese counterparts. We assess the safety and efficacy of fosphenytoin loading doses in patients with different body mass indices (BMIs).

Methods

A retrospective chart review was conducted in 410 patients who received fosphenytoin. Patients were divided into 2 groups: BMI <30 (nonobese) and BMI ≥30 (obese). Patient demographics, fosphenytoin dose administered in mg/kg body weight, renal and liver function tests, fosphenytoin drug levels, and pre- and post-fosphenytoin administration vital signs were collected to assess for adverse events. Necessity of additional antiepileptic loading doses was used as a surrogate for clinical efficacy.

Results

The median dose of fosphenytoin administered was 19 mg/kg (interquartile range 15-20). The most frequently encountered adverse event was hypotension, which occurred in 39% of the cohort. Using a Bonferroni adjustment for multiple comparisons, there were no differences in adverse events between the 2 groups. The need for additional antiepileptic loading doses was not different between the 2 groups (p = 0.07).

Conclusions

The incidence of adverse events and the need for repeat loading antiepileptic medications was similar between the 2 groups. From our findings, the patients in our study did not receive empiric loading dose adjustments and the current method of loading fosphenytoin achieves similar outcomes, regardless of the patient's BMI.

Pharmacotherapy Overview of Seizure Management in the Adult Emergency Department

Seizures are a common cause of emergency department visits, and approximately 28% of epilepsy patients present to an emergency department annually for treatment. This article will provide an overview of the pharmacotherapeutic management of seizures and anticonvulsant therapy for patients who present to the adult emergency department, including practical information for pharmacists covering or cross-covering this practice area. The benzodiazepines are reviewed as a class, including dosing strategies, pharmacodynamic considerations, and advantages and disadvantages of lorazepam, diazepam, and midazolam. Indications for the use of phenytoin and fosphenytoin will be reviewed, as well as dosing, adverse effects, and cost-effectiveness data. In addition, dosing, administration, pharmacokinetics, and adverse effects of phenobarbital, carbamazepine, and valproate will be discussed. Clinical indications for serum anticonvulsant concentration monitoring and subsequent calculation of loading doses from serum concentrations are reviewed. Since status epilepticus is a life-threatening emergency, its therapeutic management is reviewed, including the use of continuous infusion midazolam, pentobarbital, and propofol. There are many opportunities for clinical pharmacists to collaborate with other members of the health care team to optimize efficacy and minimize adverse effects of anticonvulsant agents in the emergency department setting.

Cardiovascular adverse effects of phenytoin

Phenytoin is an established drug in the treatment of acute repetitive seizures and status epilepticus. One of its main advantages over benzodiazepines is the less sedative effect. However, the possibility of cardiovascular adverse effects with the intravenous use of phenytoin cause a reluctance to its usage, and this has lead to a search for safer anticonvulsant drugs. In this study, we aimed to review the studies which evaluated the safety of phenytoin with respect to cardiovascular adverse effects. The original clinical trials and case reports listed in PUBMED in English language between the years of 1946-2014 were evaluated. As the key words, "phenytoin, diphenylhydantoin, epilepsy, seizure, cardiac toxicity, asystole, arrhythmia, respiratory arrest, hypotension, death" were used. Thirty-two clinical trials and ten case reports were identified. In the case reports, a rapid infusion rate (>50 mg/min) of phenytoin appeared as the major cause of increased mortality. In contrast, no serious cardiovascular adverse effects leading to death were met in the clinical trials which applied the recommended infusion rate and dosages. An infusion rate of 50 mg/min was reported to be safe for young patients. For old patients and patients with a cardiovascular co-morbidity, a slower infusion rate was recommended with a careful follow-up of heart rhythm and blood pressure. No cardiovascular adverse effect was reported in oral phenytoin overdoses except one case with a very high serum phenytoin level and hypoalbuminemia. Phenytoin is an effective and well tolerated drug in the treatment of epilepsy. Intravenous phenytoin is safe when given at recommended infusion rates and doses.

Clinical policy: critical issues in the evaluation and management of adult patients presenting to the emergency department with seizures

This clinical policy from the American College of Emergency Physicians is the revision of a 2004 policy on critical issues in the evaluation and management of adult patients with seizures in the emergency department. A writing subcommittee reviewed the literature to derive evidence-based recommendations to help clinicians answer the following critical questions: (1) In patients with a first generalized convulsive seizure who have returned to their baseline clinical status, should antiepileptic therapy be initiated in the emergency department to prevent additional seizures? (2) In patients with a first unprovoked seizure who have returned to their baseline clinical status in the emergency department, should the patient be admitted to the hospital to prevent adverse events? (3) In patients with a known seizure disorder in which resuming their antiepileptic medication in the emergency department is deemed appropriate, does the route of administration impact recurrence of seizures? (4) In emergency department patients with generalized convulsive status epilepticus who continue to have seizures despite receiving optimal dosing of a benzodiazepine, which agent or agents should be administered next to terminate seizures? A literature search was performed, the evidence was graded, and recommendations were given based on the strength of the available data in the medical literature.

Requirement for cardiac telemetry during intravenous phenytoin infusion: guideline fact or guideline fiction?

Guidelines recommend the use of cardiac telemetry when phenytoin is administered intravenously. Clinical areas where telemetry is available may not always be the most suitable place to monitor and treat these sick patients. We sought to clarify the evidence regarding the need for cardiac telemetry during intravenous infusion of phenytoin.

Emergency medicine pharmacy practice

Emergency medicine (EM) pharmacy practice has existed for over 30 years. In recent years, however, the specialty has grown significantly. A large number of health care systems have either a dedicated EM pharmacist or other clinical pharmacist presence in the Emergency department (ED). Over the past decade, the role of the EM pharmacist as a critical member of the health care team has expanded significantly and many innovative practices have evolved throughout the country. There is also some heterogeneity between different EM pharmacy practice sites. This article reviews the history and general concepts of EM pharmacy practice as well as illustrate some of the established benefits of an EM pharmacist.

Evaluation of intramuscular fosphenytoin vs intravenous phenytoin loading in the ED

OBJECTIVE

A comparison of length of stay in an emergency department (ED) after loading patients at risk for seizures with either intravenous (IV) phenytoin or intramuscular (IM) fosphenytoin was studied.

METHODS

This was a retrospective observational cohort study that was conducted over a 24-month period in an academic teaching hospital (693 beds). Patients included were 18 years or older, discharged from the ED without hospital admission, and loaded with either IV phenytoin or IM fosphenytoin. The primary end point was the comparison of length of stay in the ED until discharge after loading. Characterization of seizure etiology, cardiac risk factors, and adverse drug events were also observed.

RESULTS

A total of 51 patients were evaluated who received IV phenytoin compared with 59 for IM fosphenytoin. The median time-to-discharge difference between IV phenytoin vs IM fosphenytoin was 1:49 hours (95% confidence interval, 1:24-2:24 hours; P < .001). There was no statistical difference in cardiac risk factors and occurrence of adverse drug events between groups.

CONCLUSIONS

This study found that patients were discharged from the ED earlier with the loading of IM fosphenytoin compared to IV phenytoin.

Cost-effectiveness analysis of intravenous levetiracetam versus intravenous phenytoin for early onset seizure prophylaxis after neurosurgery and traumatic brain injury

Objective:

There has been growing interest in newer anti-epileptic drugs (AEDs) for seizure prophylaxis in the intensive care setting because of safety and monitoring issues associated with conventional AEDs like phenytoin. This analysis assessed the cost-effectiveness of levetiracetam versus phenytoin for early onset seizure prophylaxis after neurosurgery and traumatic brain injury (TBI).

Methods:

A cost-effectiveness analysis was conducted from the US hospital perspective using a decision analysis model. Probabilities of the model were taken from three studies comparing levetiracetam and phenytoin in post neurosurgery or TBI patients. The outcome measure was successful seizure prophylaxis regimen (SSPR) within 7 days, which was defined as patients who did not seize or require discontinuation of the AED due to adverse drug reactions (ADRs). One-way sensitivity analyses and probabilistic sensitivity analysis were conducted to test robustness of the base-case results.

Results:

The total direct costs for seizure prophylaxis were $8,784.63 and $8,743.78 for levetiracetam and phenytoin, respectively. The cost-effectiveness ratio of levetiracetam was $10,044.91 per SSPR compared to $11,525.63 per SSPR with phenytoin. The effectiveness probability (patients with no seizures and no ADR requiring change in therapy) was higher in the levetiracetam group (87.5%) versus the phenytoin group (75.9%). The incremental cost effectiveness ratio for levetiracetam versus phenytoin was $360.82 per additional SSPR gained.

Conclusions:

Levetiracetam has the potential to be more cost-effective than phenytoin for early onset seizure prophylaxis after neurosurgery if the payer’s willingness-to-pay is greater than $360.82 per additional SSPR gained.

Oral valproic acid for epilepsy--long-term experience in therapy and side effects

Valproic acid (VPA) is considered to be a drug of first choice and one of the most frequently-prescribed antiepileptic drugs worldwide for the therapy of generalized and focal epilepsies, including special epileptic. It is a broad-spectrum antiepileptic drug and is usually well tolerated. Rarely, serious complications may occur in some patients, including hemorrhagic pancreatitis, coagulopathies, bone marrow suppression, VPA-induced hepatotoxicity and encephalopathy, but there is still a lack of knowledge about the incidence and occurrence of these special side effects. Additionally, the consequences for VPA therapy and indication are more or less unclear. By literature review and own data this review addresses some of the challenges of VPA therapy and its side effects, which are not unique to epilepsy in childhood.

Contraindications to phenytoin in emergency department patients with seizures

The objective of this study was to determine what contraindications to phenytoin exist in Emergency Department (ED) patients with a medical history of seizures. We conducted a retrospective chart review using ED medical records from 2005 at two network health care EDs. We identified potential patients through ICD-9 (International Classification of Diseases, Ninth Revision) codes, selected only adult patients with a prior documented history of seizures, and reviewed these charts. From 201 charts reviewed, the three most common antiepileptic drugs taken by patients were: phenytoin (38%), levetiracetam (17%), and valproic acid (15%). For absolute contraindications to phenytoin, 4.5% of seizure patients had a known hypersensitivity to phenytoin and 1.5% were pregnant; however, no pregnant patients were taking phenytoin and only 1 person with hypersensitivity to phenytoin was taking phenytoin. For relative contraindications, 6% of seizure patients had liver disease, 8% had kidney disease, 9% had alcohol use/dependence, and 16% had diabetes. However, 55% of those with liver disease, 44% with kidney disease, 77% with alcohol use/dependence, and 53% with diabetes were currently taking phenytoin. Very few seizure patients in the ED have absolute contraindications to the use of phenytoin, and most with absolute contraindications are taking other antiepileptic drugs. Conversely, a greater proportion of seizure patients have relative contraindications and many are continuing to use phenytoin.

Generalised convulsive status epilepticus: an overview

Generalised convulsive status epilepticus is one of the most common emergencies encountered in clinical practice. This review discusses the recent understanding of this life-threatening condition with reference to the definition, pathophysiology, evaluation, complications, refractory status and prognosis. Besides epilepsy, other neurological and medical illnesses could be associated with status epilepticus. The goals of management and pharmacological approach are outlined, considering the available evidence. Prompt recognition and timely intervention, including pre-hospital treatment, are therapeutically beneficial. Refractory status should be managed in intensive care units under close monitoring. More evidence is needed for evolving the optimal treatment. A suitable treatment protocol would guide in avoiding the pitfalls at various points along the management pathway.

Oral rapid loading of valproic acid—An alternative to the usual saturation scheme?

Valproic acid (VPA) is considered to be a drug of first choice for the therapy of generalized and focal epilepsies. Due to its broad field of application and its good compatibility, VPA is one of the most frequently prescribed antiepileptic drugs (AED) worldwide. Previous studies have examined the safety and tolerability of rapid intravenous-loaded VPA in the treatment of epilepsy and status epilepticus, but rapid oral loading has not been evaluated in paediatrics systematically in the past. The standard titration scheme takes 10-14 days, some physicians prefer a slower titration of up to 4 weeks. At many institutes, especially children are treated as inpatients until the desired dosage is reached. This causes high costs to the health system and is very inconvenient for the families affected. We have developed a new loading scheme to achieve a therapeutic serum level on the third day of treatment, in order to minimize the time between the beginning of the therapy and reaching the therapeutic serum level. This is the first attempt at doing this with VPA for children with epilepsy.

Association studies of aggregated aqueous lutein diphosphate with human serum albumin and α1-acid glycoprotein in vitro: Evidence from circular dichroism and electronic absorption spectroscopy

Water-dispersible C40 carotenoid derivatives, with increased utility in mammalian therapeutic applications, include natural stereoisomer-based (3R,3'R,6'R)-lutein (beta,epsilon-carotene-3,3'-diol) derivatives. Esterification with inorganic phosphate and conversion to the sodium salt produced compounds (lutein diphosphate sodium salt; 'LdP') capable of forming red-orange aqueous suspensions after addition to USP-purified water. The aqueous dispersibility of this diphosphate salt reached 29 mg/mL without the addition of heat, detergents, co-solvents, or other additives, and was a potent direct scavenger of superoxide anion (by EPR spectroscopy) in an isolated human neutrophil assay. In the current study, preliminary evidence of the aqueous aggregation of this compound in EPR studies was confirmed using circular dichroism (CD) and electronic absorption (UV-vis) spectroscopy. Evidence for H-type ('card-pack') and J-type ('head-to-tail') self-assemblies was obtained. In vitro analysis of the potential binding interaction between LdP and human serum albumin (HSA) and alpha1-acid glycoprotein (AGP) revealed only non-specific binding with HSA (and none with AGP), contrasting with previous reports of direct interaction between astaxanthin-based soft drugs and the major plasma protein albumin. The rapid in vivo cleavage of this phosphodiester by promiscuous mammalian phosphatases may overcome the aqueous aggregation of the formulated compound. This difference in potential plasma protein interaction with prior reports reflects the subtle structural differences inherent in either the parent carotenoid scaffolds and/or the esterifying moieties.

Cost-effectiveness of oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin in the emergency department

STUDY OBJECTIVE

Oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin are all commonly used for loading phenytoin in the emergency department (ED). The cost-effectiveness of each was compared for patients presenting with seizures and subtherapeutic phenytoin concentrations.

METHODS

A simple decision tree was developed to determine the treatment costs associated with each of 3 loading techniques. We determined effectiveness by comparing adverse event rates and by calculating the time to safe ED discharge. Time to safe ED discharge was defined as the time at which therapeutic concentrations of phenytoin (>or=10 mg/L) were achieved with an absence of any adverse events that precluded discharge. The comparative cost-effectiveness of alternatives to oral phenytoin was determined by combining net costs and number of adverse events, expressed as cost per adverse events avoided. Cost-effectiveness was also determined by comparing the net costs of each loading technique required to achieve the time to safe ED discharge, expressed as cost per hour of ED time saved. The outcomes and costs were primarily derived from a prospective, randomized controlled trial, augmented by time-motion studies and alternate-cost sources. Costs included the cost of drugs, supplies, and personnel. Analyses were also performed in scenarios incorporating labor costs and savings from using a lower-urgency area of the ED.

RESULTS

The mean number of adverse events per patient for oral phenytoin, intravenous phenytoin, and intravenous fosphenytoin was 1.06, 1.93, and 2.13, respectively. Mean time to safe ED discharge in the 3 groups was 6.4 hours, 1.7 hours, and 1.3 hours. Cost per patient was 2.83 dollars, 21.16 dollars, and 175.19 dollars, respectively, and did not differ substantially in the Labor and Triage (lower-urgency area of ED) scenarios. When the measure of effectiveness was adverse events, oral phenytoin dominated intravenous phenytoin and intravenous fosphenytoin, with a lower cost and number of adverse events. With time to safe ED discharge as the outcome measure, the incremental cost-effectiveness ratios were 3.90 dollars and 387.27 dollars per hour of ED time saved for oral phenytoin versus intravenous phenytoin and for intravenous fosphenytoin versus intravenous phenytoin, respectively.

CONCLUSION

Oral phenytoin is the most cost-effective loading method in most settings. Intravenous phenytoin is preferred if one is willing to pay an additional 20.65 dollars to 44.25 dollars per patient and willing to have more adverse events for a quicker average time to safe ED discharge. It is unlikely that intravenous fosphenytoin is justifiable in any setting.