Peri-operative prophylaxis with phenytoin: dosage and therapeutic plasma levels

Evaluation of Goal Phenytoin Levels After an Initial Intravenous Loading Dose at an Academic Medical Center

BACKGROUND

Phenytoin intravenous loading doses are administered in status epilepticus to rapidly achieve therapeutic levels. Accurately assessing phenytoin levels after the initial load can be challenging because of its complex pharmacokinetic profile and nonstandardized weight-based loading doses.

OBJECTIVES

The objectives of this analysis were to determine the incidence of patients achieving goal phenytoin levels after the initial loading dose and characterize factors that contribute to achieving the goal level.

METHODS

This single-center, retrospective cohort analysis was approved by our institutional review board and included adult patients who received a phenytoin load from May 2016 to March 2021. Patients were excluded if no total phenytoin level was drawn within 24 hours of the load, if the maintenance dose was given before the first level was drawn, or if the patient was on phenytoin before the load. The major endpoint was the percentage of patients achieving a corrected goal phenytoin level of ≥10 mcg/mL after the initial load. Multivariate regression was used to determine predictors of achieving the goal phenytoin level.

RESULTS

Of the 152 patients included, 139 patients (91.4%) achieved a corrected goal level after the first load. Patients at goal received a significantly higher median weight-based loading dose (19.1 mg/kg [15.0-20.0] vs 12.6 mg/kg [10.1-15.0], P < 0.01). The multivariate analysis identified weight-based dosing as a statistically significant predictor of achieving the corrected goal level (odds ratio, 1.30; 95% CI, 1.12-1.53; P < 0.01).

CONCLUSION AND RELEVANCE

Most patients achieved a corrected goal phenytoin level after the initial load. A higher median weight-based loading dose was shown to be a predictor of achieving the goal level and should be encouraged for rapid seizure termination. Future studies are warranted to confirm patient-specific factors that affect rapid achievement of the goal phenytoin level.

Antiepileptic drugs as prophylaxis for postcraniotomy seizures

BACKGROUND

This is an updated version of the Cochrane Review previously published in 2018. The incidence of seizures following supratentorial craniotomy for non-traumatic pathology has been estimated to be between 15% to 20%; however, the risk of experiencing a seizure appears to vary from 3% to 92% over a five-year period. Postoperative seizures can precipitate the development of epilepsy; seizures are most likely to occur within the first month of cranial surgery. The use of antiepileptic drugs (AEDs) administered pre- or postoperatively to prevent seizures following cranial surgery has been investigated in a number of randomised controlled trials (RCTs).

OBJECTIVES

To determine the efficacy and safety of AEDs when used prophylactically in people undergoing craniotomy and to examine which AEDs are most effective.

SEARCH METHODS

For the latest update we searched the following databases on 29 September 2019: Cochrane Epilepsy Group Specialized Register, CENTRAL, MEDLINE, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP). We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs of people with no history of epilepsy who were undergoing craniotomy for either therapeutic or diagnostic reasons. We included trials with adequate randomisation methods and concealment; these could either be blinded or unblinded parallel trials. We did not stipulate a minimum treatment period, and we included trials using active drugs or placebo as a control group.

DATA COLLECTION AND ANALYSIS

Three review authors (JW, JG, YD) independently selected trials for inclusion, extracted data and assessed risk of bias. We resolved any disagreements through discussion. Outcomes investigated included the number of participants experiencing seizures (early (occurring within first week following craniotomy), and late (occurring after first week following craniotomy)), the number of deaths and the number of people experiencing disability and adverse effects. Due to the heterogeneous nature of the trials, we did not combine data from the included trials in a meta-analysis; we presented the findings of the review in narrative format. Visual comparisons of outcomes are presented in forest plots.

MAIN RESULTS

We included 10 RCTs (N = 1815), which were published between 1983 and 2015. Three trials compared a single AED (phenytoin) with placebo or no treatment. One, three-armed trial compared two AEDs (phenytoin, carbamazepine) with no treatment. A second three-armed trial compared phenytoin, phenobarbital with no treatment. Of these five trials comparing AEDs with placebo or no treatment, two trials reported a statistically significant advantage for AED treatment compared to controls for early seizure occurrence; all other comparisons showed no clear or statistically significant differences between AEDs and control treatment. None of the trials that were head-to-head comparisons of AEDs (phenytoin versus sodium valproate, phenytoin versus phenobarbital, levetiracetam versus phenytoin, zonisamide versus phenobarbital) reported any statistically significant differences between treatments for either early or late seizure occurrence. Only five trials reported incidences of death. One trial reported statistically significantly fewer deaths in the carbamazepine and no-treatment groups compared with the phenytoin group after 24 months of treatment, but not after six months of treatment. Incidences of adverse effects of treatment were poorly reported; however, three trials did show that significantly more adverse events occurred on phenytoin compared to valproate, placebo, or no treatment. No trials reported any results relating to functional outcomes such as disability. We considered the evidence to be of low certainty for all reported outcomes due to methodological issues and variability of comparisons made in the trials.

AUTHORS' CONCLUSIONS

There is limited, low-certainly evidence to suggest that AED treatment administered prophylactically is either effective or not effective in the prevention of postcraniotomy (early or late) seizures. The current evidence base is limited due to the different methodologies employed in the trials and inconsistencies in the reporting of outcomes including deaths and adverse events. Further evidence from good-quality, contemporary trials is required in order to assess the clinical effectiveness of prophylactic AED treatment compared to placebo or no treatment, or other AEDs in preventing postcraniotomy seizures in this select group of patients.

Antiepileptic drugs as prophylaxis for postcraniotomy seizures

BACKGROUND

This is an updated version of the Cochrane Review previously published in Issue 3, 2015.The incidence of seizures following supratentorial craniotomy for non-traumatic pathology has been estimated to be between 15% to 20%; however, the risk of experiencing a seizure appears to vary from 3% to 92% over a five-year period. Postoperative seizures can precipitate the development of epilepsy; seizures are most likely to occur within the first month of cranial surgery. The use of antiepileptic drugs (AEDs) administered pre- or postoperatively to prevent seizures following cranial surgery has been investigated in a number of randomised controlled trials (RCTs).

OBJECTIVES

To determine the efficacy and safety of AEDs when used prophylactically in people undergoing craniotomy and to examine which AEDs are most effective.

SEARCH METHODS

For the latest update we searched the following databases on 26 June 2017: Cochrane Epilepsy Group Specialized Register, the CENTRAL, MEDLINE, ClinicalTrials.gov, and the WHO International Clinical Trials Registry Platform (ICTRP). We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs of people with no history of epilepsy who were undergoing craniotomy for either therapeutic or diagnostic reasons. We included trials with adequate randomisation methods and concealment; these could either be blinded or unblinded parallel trials. We did not stipulate a minimum treatment period, and we included trials using active drugs or placebo as a control group.

DATA COLLECTION AND ANALYSIS

Three review authors (JW, JG, YD) independently selected trials for inclusion and performed data extraction and risk of bias assessments. We resolved any disagreements through discussion. Outcomes investigated included the number of participants experiencing seizures (early (occurring within first week following craniotomy), and late (occurring after first week following craniotomy)), the number of deaths and the number of people experiencing disability and adverse effects. Due to the heterogeneous nature of the trials, we did not combine data from the included trials in a meta-analysis; we presented the findings of the review in narrative format. Visual comparisons of outcomes are presented in forest plots.

MAIN RESULTS

We included 10 RCTs (N = 1815), which were published between 1983 and 2015. Three trials compared a single AED (phenytoin) with placebo or no treatment. One three-armed trial compared two AEDs (phenytoin, carbamazepine) with no treatment. A second three-armed trial compared phenytoin, phenobarbital with no treatment. Of these five trials comparing AEDs with placebo or no treatment, two trials reported a statistically significant advantage for AED treatment compared to controls for early seizure occurrence; all other comparisons showed no clear or statistically significant differences between AEDs and control treatment. None of the trials that were head-to-head comparisons of AEDs (phenytoin versus sodium valproate, phenytoin versus phenobarbital, levetiracetam versus phenytoin, zonisamide versus phenobarbital) reported any statistically significant differences between treatments for either early or late seizure occurrence.Incidences of death were reported in only five trials. One trial reported statistically significantly fewer deaths in the carbamazepine and no-treatment groups compared with the phenytoin group after 24 months of treatment, but not after six months of treatment. Incidences of adverse effects of treatment were poorly reported; however, three trials did show that significantly more adverse events occurred on phenytoin compared to valproate, placebo, or no treatment. No trials reported any results relating to functional outcomes such as disability.We considered the evidence to be of low quality for all reported outcomes due to methodological issues and variability of comparisons made in the trials.

AUTHORS' CONCLUSIONS

There is limited, low-quality evidence to suggest that AED treatment administered prophylactically is either effective or not effective in the prevention of postcraniotomy (early or late) seizures. The current evidence base is limited due to the different methodologies employed in the trials and inconsistencies in the reporting of outcomes including deaths and adverse events. Further evidence from good-quality, contemporary trials is required in order to assess the clinical effectiveness of prophylactic AED treatment compared to placebo or no treatment, or other AEDs in preventing postcraniotomy seizures in this select group of patients.

A systematic review of perioperative seizure prophylaxis during brain tumor resection: the case for a multicenter randomized clinical trial

OBJECTIVE

The majority of neurosurgeons administer antiepileptic drugs (AEDs) prophylactically for supratentorial tumor resection without clear evidence to support this practice. The putative benefit of perioperative seizure prophylaxis must be weighed against the risks of adverse effects and drug interactions in patients without a history of seizures. Consequently, the authors conducted a systematic review of prospective randomized controlled trials (RCTs) that have evaluated the efficacy of perioperative seizure prophylaxis among patients without a history of seizures.

METHODS

Five databases (PubMed/MEDLINE, Cochrane Central Register of Controlled Trials, CINAHL/Academic Search Complete, Web of Science, and ScienceDirect) were searched for RCTs published before May 2017 and investigating perioperative seizure prophylaxis in brain tumor resection. Of the 496 unique research articles identified, 4 were selected for inclusion in this review.

RESULTS

This systematic review revealed a weighted average seizure rate of 10.65% for the control groups. There was no significant difference in seizure rates among the groups that received seizure prophylaxis and those that did not. Further, this expected incidence of new-onset postoperative seizures would require a total of 1258 patients to enroll in a RCT, as determined by a Farrington-Manning noninferiority test performed at the 0.05 level using a noninferiority difference of 5%.

CONCLUSIONS

According to a systematic review of major RCTs, the administration of prophylactic AEDs after brain tumor resection shows no significant reduction in the incidence of seizures compared with that in controls. A large multicenter randomized clinical trial would be required to assess whether perioperative seizure prophylaxis provides benefit for patients undergoing brain tumor resection.

Antiepileptic drugs as prophylaxis for post-craniotomy seizures

BACKGROUND

The incidence of seizures following supratentorial craniotomy for non-traumatic pathology has been estimated to be between 15% to 20%; however, the risk of experiencing a seizure may vary from 3% to 92% over a five-year period. Postoperative seizures can precipitate the development of epilepsy; seizures are most likely to occur within the first month of cranial surgery. The use of antiepileptic drugs (AEDs) administered pre- or postoperatively to prevent seizures following cranial surgery has been investigated in a number of randomised controlled trials (RCTs).

OBJECTIVES

To determine the efficacy and safety of AEDs when used prophylactically in people undergoing craniotomy and to examine which AEDs are most effective.

SEARCH METHODS

Searches were run for the original review in January 2012. We performed subsequent searches in September 2012 and up to 04 August 2014. We searched the Cochrane Epilepsy Group's Specialized Register, the Cochrane Central Register of Controlled Trials (CENTRAL) and MEDLINE. We did not apply any language restrictions.

SELECTION CRITERIA

We included RCTs of people with no history of epilepsy who were undergoing craniotomy for either therapeutic or diagnostic reasons. Trials with adequate randomisation methods and concealment were included; these could either be blinded or unblinded parallel trials. We did not stipulate a minimum treatment period, and we included trials using active drugs or placebo as a control group.

DATA COLLECTION AND ANALYSIS

Two review authors (JP and JG) independently selected trials for inclusion and performed data extraction and risk of bias assessments. We resolved any disagreements through discussion. Outcomes investigated included the number of patients experiencing seizures (early - occurring within first week following craniotomy, and late - occurring after first week following craniotomy), the number of deaths and the number of people experiencing disability and adverse effects. Due to the heterogeneous nature of the trials, we did not combine data from the included trials in a meta-analysis; we presented the findings of the review in narrative format.

MAIN RESULTS

We included eight RCTs (N = 1602), which were published between 1983 and 2013. Three trials compared a single AED (phenytoin) with a placebo or no treatment. One three-arm trial compared two AEDs (carbamazepine, phenytoin) with no treatment. A second three-arm trial compared phenytoin, phenobarbital and no treatment. Three other trials were head-to-head trials of AEDs (phenytoin vs. valproate; zonisamide vs. phenobarbital) and levetiracetam vs. phenytoin. Of the five trials comparing AEDs with controls, only one trial reported a significant difference between AED treatment and controls for early seizure occurrence. All other comparisons were non-significant. Of the head-to-head trials, none reported statistically significant differences between treatments for either early or late seizures. One head-to-head trial showed an increase in the number of deaths following one AED treatment compared to another AED treatment. Incidences of adverse effects of treatment were poorly reported, and the most trials reported no significant differences between treatment groups. However data on adverse events were limited.

AUTHORS' CONCLUSIONS

There is little evidence to suggest that AED treatment administered prophylactically is effective or not effective in preventing post-craniotomy seizures. The current evidence base is limited due to the differing methodologies employed in the trials and inconsistencies in reporting of outcomes. Further evidence from good-quality, contemporary trials is required in order to assess the effectiveness of prophylactic AED treatment compared to control groups or other AEDs in preventing post-craniotomy seizures properly.

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.

Antiepileptic drugs as prophylaxis for post-craniotomy seizures

BACKGROUND

The incidence of seizures following supratentorial craniotomy for non-traumatic pathology has been estimated to be 15% to 20%; however, the risk of experiencing a seizure may vary from 3% to 92% over a five-year period. Postoperative seizures can precipitate the development of epilepsy; seizures are most likely to occur within the first month of cranial surgery. The use of antiepileptic drugs (AEDs) administered pre- or postoperatively to prevent seizures following cranial surgery has been investigated in a number of randomised controlled trials.

OBJECTIVES

To determine the efficacy and safety of AEDs when used prophylactically in people undergoing craniotomy and to examine which AEDs are most effective.

SEARCH METHODS

We searched the Cochrane Epilepsy Group's Specialized Register (September 2012), the Cochrane Central Register of Controlled Trials (CENTRAL, The Cochrane Library Issue 9, 2012), and MEDLINE (1946 to September 2012). No language restrictions were imposed.

SELECTION CRITERIA

Randomised controlled trials of people with no history of epilepsy who were undergoing craniotomy for either therapeutic or diagnostic reasons were included. Trials with adequate randomisation methods and concealment were included; these could either be blinded or unblinded parallel trials. No minimum treatment period was stipulated, trials using active drugs or placebo as a control group were included.

DATA COLLECTION AND ANALYSIS

Two review authors (JP and JG) independently selected trials for inclusion and carried out data extraction and risk of bias assessments. Any disagreements were resolved through discussion. Outcomes investigated included the number of patients experiencing seizures (early - occurring within first week following craniotomy and late - occurring after first week following craniotomy), the number of deaths and the number of people experiencing disability and adverse effects. Due to the heterogeneous nature of the trials, data from the trials were not combined in a meta-analysis; the findings of the review are presented in narrative format.

MAIN RESULTS

Six RCTs (N = 1398) were eligible for inclusion within the review with publication dates ranging between 1983 and 1999. Two trials compared a single AED (phenytoin) with a placebo. One three-arm trial compared two AEDs (carbamazepine, phenytoin) with no treatment. A second three-arm trial compared phenytoin, phenobarbital and no treatment. Two other trials were head-to-head trials of AEDs (phenytoin vs. valproate and zonisamide vs. phenobarbital). Of the four trials comparing AEDs with controls only one trial reported a significant difference between AED treatment and controls for early seizure occurrence. All other comparisons were non-significant. Of the head-to-head trials, none reported statistically significant differences between treatments for either early or late seizures. One head-to-head trial showed an increase in the number of deaths following one AED treatment compared to another AED treatment. Incidences of adverse effects of treatment were poorly reported, no significant differences between treatment groups were found due to the limited number of reported occurrences.

AUTHORS' CONCLUSIONS

There is little evidence to suggest that AED treatment administered prophylactically is effective or not effective in preventing post-craniotomy seizures. The current evidence base is limited due to the differing methodologies employed in the trials and inconsistencies in reporting of outcomes. Further evidence from good-quality, contemporary trials is required in order to assess the effectiveness of prophylactic AED treatment compared to control groups or other AEDs in preventing post-craniotomy seizures properly.

[Primary prophylaxis of early seizures after surgery of cerebral supratentorial tumors: Group for the Study of Functional-Sterotactic Neurosurgery of The Spain Society of Neurosurgery recommendations]

Our review of the literature is basically focused on the primary prophylaxis of early seizures after surgery of cerebral supratentorial tumors, with the aim of suggesting several recommendations in medical antiepileptic treatment to avoid this kind of seizures which occur immediately after surgery. In conclusion, it is recommended to provide criteria for prophylaxis of early seizures after surgery of cerebral supratentorial tumors. It́s recommended a one week treatment with antiepileptic drugs in patients who didńt have seizures jet, starting immediately after the surgical treatment. If seizures appear during progress of the disease, a large period treatment will be needed. Preferred antiepileptic treatment is intravenous and with a low interactions profile. Levetiracetam, followed by valproic acid seem to be most appropriated drugs due to their properties and protective effects, particularly for our patients requirements. These recommendations are considered a general proposal to effective clinical management of early seizures after surgery, not taking into account the single circumstances of our patients. Always, clinical features of the patients could modify even significantly these guides in the benefit of each patient.

Prophylactic antibiotics and anticonvulsants in neurosurgery

The prophylactic administration of antibiotics to prevent infection and the prophylactic administration of anticonvulsants to prevent first seizure episodes are common practice in neurosurgery. If prophylactic medication therapy is not indicated, the patient not only incurs the discomfort and the inconvenience resulting from drug treatment but is also unnecessarily exposed to adverse drug reactions, and incurs extra costs. The main situations in which prophylactic anticonvulsants and antibiotics are used are described and those situations we found controversial in the literature and lack further investigation are identified: anticonvulsants for preventing seizures in patients with chronic subdural hematomas, antiepileptic drugs for preventing seizures in those suffering from brain tumors, antibiotic prophylaxis for preventing meningitis in patients with basilar skull fractures, and antibiotic prophylaxis for the surgical introduction of intracranial ventricular shunts.In the following we present systematic reviews of the literature in accordance with the standard protocol of The Cochrane Collaboration to evaluate the effectiveness of the use of these prophylactic medications in the situations mentioned. Our goal was to efficiently integrate valid information and provide a basis for rational decision-making.

Antiepileptic drugs for preventing seizures in people with brain tumors

BACKGROUND

Seizures can present at any time before or after diagnosis of a brain tumor. The risk of seizures varies by tumor type and its location in the brain. For a long time we believed that preventing seizures with antiepileptic drugs (seizure prophylaxis) was effective and necessary, but the supporting evidence was little and mixed. Such evidence was the basis for previous reviews to conclude that seizure prophylaxis was ineffective in people with brain tumors.

OBJECTIVES

To estimate the effectiveness of seizure prophylaxis in people with brain tumors, and to estimate the adverse event rates in the identified clinical trials.

SEARCH STRATEGY

A search strategy that included free-text and MeSH terms in LILACS, EMBASE, PubMed, CENTRAL, and The Cochrane Library (1966 to 2007).

SELECTION CRITERIA

Controlled clinical trials with random allocation, blinded or unblinded, and placebo or observation in the control groups.

DATA COLLECTION AND ANALYSIS

We screened the articles, extracted the data, and rated the validity of each trial to assess the risk of bias. Our primary outcome was the occurrence of a first seizure. The secondary outcome was adverse events. We pooled the aggregate data for each outcome into a random-effects model meta-analysis using the relative risk (RR). For adverse events, we also included the number needed to harm (NNH) using the absolute risk increase to compute the NNH.

MAIN RESULTS

There was no difference between the treatment interventions and the control groups in preventing a first seizure in participants with brain tumors. The risk of an adverse event was higher for those on antiepileptic drugs than for participants not on antiepileptic drugs (NNH 3; RR 6.10, 95% CI 1.10 to 34.63; P = 0.046).

AUTHORS' CONCLUSIONS

The evidence is neutral, neither for nor against seizure prophylaxis, in people with brain tumors. These conclusions apply only for the antiepileptic drugs phenytoin, phenobarbital, and divalproex sodium. The decision to start an antiepileptic drug for seizure prophylaxis is ultimately guided by assessment of individual risk factors and careful discussion with patients.

Prevention of early postoperative seizures in patients with primary brain tumors: preliminary experience with oxcarbazepine

Early postoperative seizures are defined as those that appear within the first week after surgery and are a well-known and feared complication in patients with supratentorial brain tumors. Few studies have investigated the value of pharmacological prophylaxis in the prevention of postoperative seizures in these patients and their outcome has not been consistent. Furthermore, the efficacy of the new generation of antiepileptic agents in the prophylaxis of perioperative seizures has not been assessed so far. We analyzed the data related to 150 patients harboring supratentorial brain gliomas with the aim to assess the efficacy of oxcarbazepine in preventing the occurrence or the recurrence of early postoperative seizures and its tolerability when it is rapidly titrated. Only four patients (2.7%) experienced seizures within the first week after surgery. Patients did not report disturbances during the titration phase. Regarding adverse events in the first week, six patients (4%) showed minor skin rash. Persistent symptomatic hyponatremia never occurred. Our data showed that oxcarbazepine can be a good alternative to traditional antiepileptic agents in the prevention of perioperative seizures being efficacy, ease of use (rapid titration in 3 days, not requiring close plasma concentration monitoring) and good tolerability (no major side effects during titration and during the first postoperative week) the key factors. Moreover, oxcarbazepine can be a valid choice when long-term therapy is required because of the low interaction with other drugs and the low hematological side effects.

Seizure prophylaxis in patients with brain tumors: a meta-analysis

OBJECTIVE

To assess whether antiepileptic drugs (AEDs) should be prescribed to patients with brain tumors who have no history of seizures.

METHODS

We performed a meta-analysis of randomized controlled trials (1966-2004) that evaluated the efficacy of AED prophylaxis vs no treatment or placebo to prevent seizures in patients with brain tumors who had no history of epilepsy. Summary odds ratios (ORs) were calculated using a random-effects model. Three subanalyses were performed to assess pooled ORs of seizures in patients with primary glial tumors, cerebral metastases, and meningiomas.

RESULTS

Of 474 articles found in the initial search, 17 were identified as primary studies. Five trials met inclusion criteria: patients with a neoplasm (primary glial tumors, cerebral metastases, and meningiomas) but no history of epilepsy who were randomized to either an AED or placebo. The 3 AEDs studied were phenobarbital, phenytoin, and valproic acid. Of the 5 trials, 4 showed no statistical benefit of seizure prophylaxis with an AED. Meta-analysis confirmed the lack of AED benefit at 1 week (OR, 0.91; 95% confidence interval [CI], 0.45-1.83) and at 6 months (OR, 1.01; 95% CI, 0.51-1.98) of follow-up. The AEDs had no effect on seizure prevention for specific tumor pathology, including primary glial tumors (OR, 3.46; 95% CI, 0.32-37.47), cerebral metastases (OR, 2.50; 95% CI, 0.25-24.72), and meningiomas (OR, 0.62; 95% CI, 0.10-3.85).

CONCLUSIONS

No evidence supports AED prophylaxis with phenobarbital, phenytoin, or valproic acid in patients with brain tumors and no history of seizures, regardless of neoplastic type. Subspecialists who treat patients with brain tumors need more education on this issue. Future randomized controlled trials should address whether any of the newer AEDs are useful for seizure prophylaxis.

Postoperative seizures: epidemiology, pathology, and prophylaxis

The risk of epileptic seizures after craniotomy is extremely important but the incidence of postoperative epilepsy varies greatly, depending on the patient's conditions such as primary diseases, severity of surgical insult, and pre-existing epilepsy. Animal studies suggest that neurosurgical insults lead to seizures by two different mechanisms: One mechanism is mediated by free radical generation and the other by impaired ion balance across the cell membrane caused by ischemia or hypoxia. Conventional antiepileptic agents such as phenytoin, phenobarbital, carbamazepine, and valproic acid are promising for the prevention of early seizures, but the effect in preventing postoperative epilepsy is still controversial. Studies on the prophylactic effect of newer antiepileptic agents in craniotomized patients were very limited. Zonisamide, an antiepileptic agent with antiepileptogenic, free radical scavenging and neuroprotective actions in experimental animals, showed promising effects against postoperative epilepsy in a randomized double blind controlled trial. Prophylactic treatment for craniotomized patients significantly prevented the development of partial seizures during the follow-up period. Most recent studies have not supported the prophylactic use of antiepileptic agents in craniotomized patients, but further studies are required.

Brain tumors

The total care of a patient with an incurable brain tumor is a complex task. It is best performed by a team of specialized care providers including neurologists, neuro-oncologists, neurosurgeons, radiation oncologists, nurses, neuropsychologists, social workers, and physical and occupational therapists. Hospice providers, and spiritual counselors provide particular skilled services and comfort to patients nearing the end of life. The role and prominence of each team member evolves during the course of the illness as the disease progresses and the symptoms and needs of the patient change. Family members often provide the bulk of the direct care, and themselves require support, education, and counseling. While we currently lack curative therapies for most patients with malignant brain tumors, careful attention to symptom diagnosis and management can greatly enhance the quality of life of a patient with a brain tumor throughout the course of the illness and at the end of life.

Anticonvulsant prophylaxis and timing of seizures after aneurysmal subarachnoid hemorrhage

OBJECTIVE

There is no evidence that seizure prophylaxis is indicated after aneurysmal subarachnoid hemorrhage (SAH). This study examines prophylactic antiepileptic drug (AED) prescription and the occurrence of seizures within a single university-affiliated institution.

METHODS

The authors reviewed 95 SAH patient charts using standardized forms. Variables included prophylaxis duration, seizure incidence and timing, CT findings, AED adverse events, and 1-year patient follow-up.

RESULTS

Prehospital seizures occurred in 17.9% (17/95) of patients; another 7.4% (7/95) had a questionable prehospital seizure. In-hospital seizures occurred in 4.1% (4/95) of patients, a mean of 14.5 +/- 13.7 days from ictus; three of these four patients were receiving an AED at the time of seizure. Inpatient AED were prescribed to 99% of the cohort for a median of 12 (range 1 to 68) days. Approximately 8% of the cohort had posthospital discharge seizures; this included the patients who had prehospital or in-hospital seizures, 50% of whom were receiving AED therapy at the time of the seizure. Adverse effects occurred in 4. 1%; none were serious. The thickness of cisternal clot was associated with having a seizure; no other clinical predictors were identified. Having a seizure at any time did not adversely affect outcome.

CONCLUSIONS

In this SAH population, the majority of seizures happened before medical presentation. In-hospital seizures were rare and occurred more than 7 days postictus for patients receiving AED prophylaxis. The vast majority of putative clinical predictors did not help predict the occurrence of seizures; only the thickness of the cisternal clot was of value in predicting seizures. Patient selection for and the efficacy and timing of AED prophylaxis after SAH deserve prospective evaluation.