Epilepsy - Tamucc Nurisng Pharmacology PDF

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Tamucc Nurisng Pharmacology...

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Epilepsy/Seizures/AEDs: Epilepsy: Syndrome of CNS dysfunction; Most common chronic neurologic illness; Results from excessive electrical activity of neurons located in superficial area of brain (gray matter); Following terms are often used interchangeably but they do not have the same meaning; Seizure (brief episode of abnormal electrical activity in nerve cells of the brain); Convulsions (involuntary spasmodic contractions of any or all voluntary muscles throughout the body, including skeletal, facial, and ocular muscles); Epilepsy (chronic, recurrent pattern of seizures); Primary (idiopathic): cause cannot be determined, roughly 50% of epilepsy cases; Secondary (symptomatic): distinct cause is identified (trauma, infection, cerebrovascular disorder, febrile in young children). Seizures: Generalized onset seizures: formerly known as grand mal seizures, tonic-clonic seizures, aclonic, myoclonic, absence seizures; Partial onset seizures: simple (formerly known as petit mal seizures), complex, secondary generalized tonic-clonic; Unclassified seizures. AED’s (anticonvulsants): To control or prevent seizures while maintaining a reasonable quality of life; minimize adverse effects & drug-induced toxicity; lifelong; serum drug concentrations must be measured (therapeutic drug monitoring); used to manage seizure disorders: barbiturates- not 1st choice usually avoided, hydantoins- phenytoin (Dilantin), Iminostilbenes plus valproic acid, second- and third-generation AEDs MOA: not know; pharmacologic effects: reduce nerve’s ability to be stimulated, suppress transmission of impulses from one nerve to the next, decreased speed of nerve impulse conduction within a neuron Indications: prevention/ control of seizures, long-term maintenance therapy for chronic, recurring seizures, acute treatment of convulsions and status epilepticus; Contraindications: known drug allergy; other contraindications exist but are more drugspecific, including hepatic failure, certain blood diseases, narrow-angle glaucoma, and familial short QT syndrome. Adverse Effects: leads to changing the medication; Black box warning as of 2008: suicidal thoughts and behavior; long-term therapy w/ phenytoin (Dilantin) may cause gingival hyperplasia, acne, hirsutism (excessive hair), & Dilantin facies Toxicity & Management: toxic symptoms in AEDs are idiosyncratic and are believed to occur more frequently in the 1st generation AEDs (carbamazepine). Possible symptoms may include ataxia, dystonia, sinus tachycardia, hyperthermia, coma, arrhythmias, respiratory depression, and death. Valproic acid: can have toxic effects that include metabolic and hematological disruption, pancreatitis, CNS depression, optic nerve atrophy, respiratory depression, cardiopulmonary arrest, brain edema, and coma. Treatment can range from supportive measures to high-flow hemodialysis, plasmapheresis, or charcoal hemoperfusion.

Interactions: numerous drug interactions; induce hepatic metabolism resulting in reduction of effects of other drugs; interfere with birth control (ONLY ORAL MEDICATION): substitute→ IUDs, depo-, implants; avoid grapefruit w/ carbamazepine Nursing Process: Assessment: health history, including current medications, drug allergies, liver function studies: CBC, vitals, surgery history, aura: occurs before seizure, location, duration, frequency, serum drug levels; oral drugs → take regularly at the same time, take with meals to reduce GI upset, do not crush, chew or open extended-release forms; if patient is NPO for a procedure, contact prescriber regarding AED dosage, never discontinue w/out doctor’s orders; Intravenous forms → IV delivery usually given slowly, monitor vitals, avoid extravasation fluids, use normal saline w/ phenytoin (Diltantin). Implementations: teach patients to keep a journal to monitor → response, seizure occurrence & descriptions, adverse effects, instruct patients to wear a medical alert tag or ID, should not be stopped abruptly, follow driving recommendations, teach patients it is long-term/ lifelong. Evaluation: check for decreased/ absent seizure activity, mental status changes, mood changes, changes in level of consciousness/ sensorium, eye problems, visual disorders, sore throat, fever...