751 status epilepticus

Seizure initiation is likely caused by an imbalance between excitatory (e.g., glutamate, calcium, sodium, substance P, and neurokinin B) neurotransmission and inhibitory (y-aminobutyric acid, adenosine, potassium, neuropeptide Y, opioid peptides, and galanin) neurotransmission. 

Seizure maintenance is largely caused by glutamate acting on postsynap-tic N-methyl-D-aspartate and a-amino-3-hydroxy-5-methyl-isoxazole-4-propionate/akinate receptors. Sustained depolarization can result in neuronal death. 

There is evidence that yaminobutyric acid A receptors may be modified during SE and become less responsive to endogenous agonists and antagonists. Two phases of GCSE have been identified. During phase I, each seizure produces marked increases in plasma epinephrine, norepinephrine, and steroid concentrations that may cause hypertension, tachycardia, and cardiac arrhythmias. Muscle contractions and hypoxia can cause acidosis, and hypotension, shock, rhabdomyolysis, secondary hyperkalemia, and acute tubular necrosis may ensue. 

Phase II begins 60 minutes into the seizure, and the patient begins to decompensate. The patient may become hypotensive, and cerebral blood flow may be compromised. Glucose may be normal or decreased, and hyperthermia, respiratory deterioration, hypoxia, and ventilatory failure may develop. 

In prolonged seizures, motor activity may cease, but electrical seizures may persist. 

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Occasionally, status epilepticus (an emergency situation characterized by continual seizure activity with no interruptions) can occur. Diazepam (Valium) is most often the initial drug prescribed for this condition. However, because the effects of diazepam last less than 1 hour, a longer-lasting anticonvulsant, such as phenytoin or phenobarbital, also must be given to control the seizure activity. 

Promoting an Optimal Response to Therapy When administering an anticonvulsant, the nurse must not omit or miss a dose (except by order of the primary health care provider). An abrupt interruption in ther-apy by omitting a dose may result in a recurrence of the seizures. In some instances, abrupt withdrawal of an anticonvulsant can result in status epilepticus. 

The nurse is preparing to administer an anticonvulsant for status epilepticus. The primary care provider prescribes Luminal 200 mg IV. The drug is available in a dosage of 60 mg mL. The nurse administers... 

Vass, K., Berger, M.L., Nowak, T.S.J., Welch, W.J. (1989). Induction of stress protein hsp70 in nerve cells after status epilepticus in the rat. Neurosci. Lett. 100, 259-264. 

Clonazepam, a typical 1 4 benzodiazepine, is effective in absence seizures, myoclonic jerks and tonic-clonic seizures and given intravenously it attenuates status epilepticus. It is less sedative than phenobarbitone but tolerance develops and its withdrawal, as... 

Refractory status epilepticus (patient must have a protected airway)... 

Anticonvulsant pharmacotherapy for status epilepticus (uncommon—consider alternative etiology)... 

Explain the urgency of diagnosis and treatment of status epilepticus. 

Identify the treatment options available for termination of status epilepticus. 

Formulate an initial treatment strategy for a patient in generalized convulsive status epilepticus. 

Compare the pharmacotherapeutic options for refractory status epilepticus. 

Describe adverse drug events associated with the pharmacotherapy of status epilepticus. 

Recommend monitoring parameters for a patient in status epilepticus. 

O Status epilepticus is a neurologic emergency that can lead to permanent brain damage or death. 

It is important to evaluate for possible etiologies of status epilepticus and treat any underlying causes in order to optimize seizure control. 

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