Status epilepticus

Status epilepticus can be divided into two categories: convulsive and nonconvulsive (NCSE). The symptoms can be managed by initially introducing a seizure suppressing medication as the first stage of the treatment, which optimally works only for that stage because any delay will reduce the efficacy of those medications. Convulsive status epilepticus commonly affects the elderly and young children, with a mortality rate of up to 20–30% of elderly patients and 0–3% of young children. Patients who survive initial onset are often left with cognitive and neurological defects. Refractory status epilepticus is defined as status epilepticus that continues despite treatment with benzodiazepines and one antiepileptic drug. Super-refractory status epilepticus is defined as status epilepticus that continues or recurs 24 hours or more after the onset of anaesthetic therapy, including those cases where status epilepticus recurs on the reduction or withdrawal of anesthesia. Nonconvulsive Nonconvulsive status epilepticus is a relatively long duration change in a person's level of consciousness without large-scale bending and extension of the limbs due to seizure activity. In the case of complex partial status epilepticus, the seizure is confined to a small area of the brain, normally the temporal lobe. Absence status epilepticus is marked by a generalized seizure affecting the whole brain. An electroencephalogram (EEG) is needed to differentiate between the two conditions. The cases of nonconvulsive status epilepticus are characterized by a long-lasting stupor, staring, and unresponsiveness. Recent studies indicated 50% of cases involve patients that are semi-conscious in a way that they can respond but are confused spontaneously. Only 6% have shown a decelerated thought process. About 44% of cases of nonconvulsive status epilepticus are marked by a prolonged or fragmentary coma. ==Causes==

Only 25% of people who experience seizures or status epilepticus have epilepsy. The following is a list of possible causes: • Stroke • Hemorrhage • Intoxicants or adverse reactions to drugs • Insufficient dosage or sudden withdrawal of a medication (especially anticonvulsants) • Insufficient dosage or sudden withdrawal of benzodiazepine(s) medication (akin to alcohol withdrawal); itself a class of antiseizure/anticonvulsant medications • Consumption of alcoholic beverages while on an anticonvulsant, or alcohol withdrawal • Dieting or fasting while on an anticonvulsant • Starting on a new medication that reduces the effectiveness of the anticonvulsant or changes drug metabolism, decreasing its half-life, leading to decreased blood concentrations • Developing a resistance to an anticonvulsant already being used • Gastroenteritis while on an anticonvulsant, where lower levels of anticonvulsant may exist in the bloodstream due to vomiting of gastric contents or reduced absorption due to mucosal edema • Developing a new, unrelated condition in which seizures are coincidentally also a symptom, but are not controlled by an anticonvulsant already used • Metabolic disturbances—such as affected kidney and liver • Sleep deprivation of more than a short duration is often the cause of a (usually, but not always, temporary) loss of seizure control • Dehydration – moderate- to severe, especially when combined with any single factor above ==Diagnosis==

Diagnostic criteria vary, though most practitioners diagnose as status epilepticus for: one continuous, unremitting seizure lasting longer than five minutes, or recurrent seizures without regaining consciousness between seizures for greater than five minutes. New-onset refractory status epilepticus (NORSE) is a clinical presentation, not a specific diagnosis, in a patient without active epilepsy or other relevant neurological disorder, with new onset of refractory status epilepticus without a clear structural, toxic or metabolic cause. ==Treatments==

that can be inserted rectally is often prescribed to caregivers of people with epilepsy. This enables treatment of multiple seizures prior to being able to seek medical care. Benzodiazepines are the preferred initial treatment after which typically phenytoin or fosphenytoin is given. Benzodiazepines When given intravenously, lorazepam appears to be superior to diazepam for stopping seizure activity. Intramuscular midazolam appears to be a reasonable alternative especially in those who are not in hospital. Alternatively, medication, such as glucagon, should be given through the bone (intraosseously). Cited advantages of clonazepam include a longer duration of action than diazepam and a lower propensity for the development of acute tolerance than lorazepam. The use of clonazepam for this indication is not recognized in North America, perhaps because it is not available as an intravenous formulation there. Sometimes, the failure of lorazepam alone is considered to be enough to classify a case of SE as refractory–that is, resistant to treatment. Phenytoin and fosphenytoin Phenytoin was once another first-line therapy, although the prodrug fosphenytoin can be administered three times as fast and with far fewer injection site reactions. If these or any other hydantoin derivatives are used, then cardiac monitoring is necessary if they are administered intravenously. Because the hydantoins take 15–30 minutes to work, a benzodiazepine or barbiturate is often coadministered. Because of diazepam's short duration of action, they were often administered together anyway. At present, these remain recommended second-line, follow-up treatments in the acute setting per guidelines by groups like Neurocritical Care Society (United States). That said, even when benzodiazepines are available, certain algorithms–including in the United States–indicate the use of phenobarbital as a second- or third-line treatment in SE. Such use is adjunctive. At least one U.S. study showed phenobarbital, when used alone, controlled about 60% of seizures, hence its preference as an add-on therapy. Others If this proves ineffective or if barbiturates cannot be used for some reason, then a general anesthetic such as propofol may be tried; sometimes it is used second after the failure of lorazepam. This would entail putting the person on artificial ventilation. Propofol has been shown to be effective in suppressing the jerks seen in myoclonus status epilepticus. Ketamine, an NMDA antagonist drug, can be used as a last resort for drug-resistant status epilepticus. Lidocaine has been used in cases that do not improve with other more typical medications. One concern is that seizures often begin again 30 minutes after it is stopped. Additionally, it is not recommended in those with heart or liver problems. ==Prognosis==

While sources vary, about 16 to 20% of first-time SE patients die; ==Epidemiology==

In the United States, about 40 cases of SE occur annually per 100,000 people. Prevalence It was found that status epilepticus is more prevalent among African Americans than Caucasian Americans by threefold in North London, and that Asian children have recorded a relatively higher susceptibility of developing the more severe form of febrile seizures. These ethnic distribution rates indicate the genetic contribution to the susceptibility of status epilepticus. Also, studies have shown that status epilepticus is more common in males. Aetiology Many studies have found out that age is the most related factor to the etiology of status epilepticus, since 52% of febrile seizures was found in children, while for adults acute cerebralvascular cases was more common, side by side with hypoxia and other metabolic causes. ==Research==

Allopregnanolone was being studied as a treatment for super-resistant status epilepticus, but was found to have no benefit over placebo. == See also ==