Module 12 (Patho 2).docx

Seizure Disorders Lecture Guide Seizure: Uncontrolled (Depolarization) electrical discharge from a group of neurons in the cerebral cortex. Not a disease but can be acute. sign of underlying CNS dysfunction, acute. Epilepsy: or Epileptic syndrome chronic neurological condition where the in...

Seizure Disorders Lecture Guide Seizure: Uncontrolled (Depolarization) electrical discharge from a group of neurons in the cerebral cortex. Not a disease but can be acute. sign of underlying CNS dysfunction, acute. Epilepsy: or Epileptic syndrome chronic neurological condition where the individual is susceptible to recurrent seizures. recurring seizures without provocation Seizure is a sign of possible epilepsy; if a person has recurrent seizure activity it would be classified as epilepsy or epileptic syndrome. This means all people with epilepsy have seizure activity but not everyone who has seizure activity has epilepsy. Although anyone could have a seizure under the right conditions. Etiology: 70% related to __idiopathic___. 30%: related to __head injury and brain tumor__. Uncontrolled electrical discharge: many nerve cells in the brain “fire” _to quickly_ causing an “_electrical__ __storm__…” Sign of underlying dysfunction IICP (increased intracranial pressure): ischemia brain is an irritated brain. Electrolyte imbalance: severe hypomagnesemia or hyponatremia. What could seizure disorder and cardiac dysrhythmia have in common? Check all that apply. ✅ can be acute or chronic ✅ sign of underlying disease ✅ ischemia is an etiology ✅ diagnosis includes electrical conduction studies ✅ low magnesium could be an etiology Seizure activity related to: Low seizure threshold - meaning it doesn't take much stimulation to produce a seizure. Brain tumors, hematomas - Blot clots in the brain that present with seizure activity because of ischemia. Brain attack - increase pressure in the brain and result in seizures ischemia. Head trauma: concussion, contusion could disrupt electrical activity. Fever, electrolyte imbalance - low magnesium; low sodium. Fever in children - is an etiology for seizures that’s usually a very temporary thing and not a permanent thing. Work-up Can you determine what provoked the seizure? Most seizures are unprovoked meaning they're idiopathic. Who is in the at risk population? Children (fever activity), IICP, people who have electrolyte imbalance such as low magnesium, low sodium, and etc. Seizure activity related to: Fever in ____children______ Electrolyte imbalance Hypocalcemia, hypomagnesemia, hyponatremia Arrange the steps in order: hyponatremia to seizure activity. _8_ Seizures _1_ Water intoxication _2_ Hyponatremia _7_ Cerebral Ischemia _5_ Brain cells swell _3_ Osmolarity of the blood drops _6_ Blood vessels are compressed _4_ Fluid is pulled from blood vessels into the brain Hypocalcemia Loss of Ca: __sodium__ channel gate keeper Calcium ⇒ prevent unwanted entry of _sodium__ into nerve cells of brain → maintain normal threshold _stimulus_ ⇒ _↓_ risk for seizures More sodium channels open ⇒ _easier depolarization ⇒ _↑_ risk for seizure Arrange the steps in order: hypocalcemia to seizure activity. _4_ seizures _2_ sodium channels open _1_ hypocalcemia _3_ lower threshold stimuli Hypomagnesemia Hypothesis: Need Mg++ for parathyroid hormone (PTH) activity and calcium absorption. low Mg++ ⇒ low calcium ⇒ more sodium channels are open ⇒ less stimuli required to depolarize ⇒ neurons are hyper excitable ⇒ risk for seizure activity. IICP (increased intracranial pressure) IICP compresses arterial blood supply ⇒ reducing oxygen to the brain, which results in ischemia. Examples of IICP and ischemia: Trauma Hemorrhage Brain attack Brain tumor Review: Explain why IICP can result in seizure activity. – Fill in the blanks. IICP means the volume within the cranial cavity has __↑__ Pressure within the cranium (intracranial pressure) __↑__ Blood vessels are _compressed of squeezed_ Oxygen flow is _↓_ Brain cells become __ischemic___ …and cell membrane can become disrupted Sodium moves intracellular ⇒ rapid depolarization ⇒ seizures activity is possible. Why can meningitis and encephalitis provoke seizures? Inflammation ⇒ more histamine from mast cells Vasodilation ⇒ fluid shifts from inside the capillaries to the brain tissue The brain swells Pressure within the cranium (intracranial pressure) ____ Blood vessels are compressed Oxygen flow is _↓_ Brain cells become __ischemic___ …and cell membrane can become disrupted Sodium moves intracellular ⇒ rapid depolarization ⇒ seizures Why seizure activity can be related to brain tumor Senator Kennedy died of a malignant brain tumor. The tumor presented as a seizure. The seizure was caused by tumor compressing blood supply ⇒ __ischemia__ around the tumor ⇒ cell membrane more permeable to Sodium ⇒ rapid and erratic depolarization ⇒ seizure is provoked by a tumor. Epilepsy Syndrome Onset: Usually begins before age 20. Is genetic mutation in some people. Ion channel defects, which affect nerve depolarization. Review Question: Chronic seizure activity [epileptic syndrome]: a. hypomagnesemia is a risk factor b. is often related to low serum calcium or sodium c. usually means swelling in the brain d. may be related to an imbalance of neurotransmitters Which of the following images represents a common age of onset for epileptic syndrome? Can an acute onset of seizure activity turn into epilepsy? Yes, only if the seizures are recurrent. Types of Seizures Partial seizure “…the disturbance occurs in just one part of the brain, affecting whatever physical or mental activity that area controls.” Simple partial seizure Affects only _1__ part of brain Without loss of consciousness S/S Depend on the Area of Brain Involved in Seizure Activity Example: Temporal lobe ~ “Seizure starts as part of the brain that processes emotions, fight or flight reactions, and short-term memory. Many who have temporal lobe seizures may experience feeling {aura} — ranging from euphoria to fear, Deja vu, and hallucinations of taste or smell — at the onset of their seizures.” Complex partial seizure Affects more than one part of the brain Will have loss of consciousness Begins in one area and impulse spreads out to both hemispheres Generalized seizure Convulsive or non-convulsive Loss of consciousness or awareness Absence seizure – generalized, non-convulsive Absent for awareness of surroundings Tonic-clonic (grand mal) seizure Involves entire body characterized by muscle rigidity Rhythmic muscle contractions and loss of consciousness Concern: a period of apnea; when a tonic clonic seizure occurs over and over again there is a risk for respiratory complications in the body called status epilepticus. Which causes a seizure activity to be interrupted in order for respiratory functions to be returned and cells can become oxygenated. Diagnosis: Documenting seizure activity – visualization Exclude/Rule out: Metabolic etiology Hyponatremia Hypocalcemia Alkalosis Internal problems Ischemia Tumors External problems Trauma Drug abuse Electroencephalogram (EEG) Checks electro activity as it passes through the brain. Just as EKG looks at electrical activity that passes through the heart. Treatment: Identify what provokes the seizure and treat it such as: Fever in children. IICP Inflammatory conditions Space occupying tumors Bleeds: intracerebral hemorrhage or SAH …. Hematomas: epidural and subdural. Ischemia - restore perfusion in cerebrovascular disease. Correct electrolyte imbalances Goal: __↑__ the seizure threshold Make it harder for nerve cells to depolarize. Review Fill in the Blanks Dysrhythmia is to the heart what seizure is to the brain. Seizures can occur as a result of imbalance between neurotransmitters that excite (acetylcholine) and those that inhibit (GABA). Who am I? I begin in one area – the temporal lobe My impulse spreads out to both hemispheres I impaired consciousness Who am I? = Complex partial seizures. Who am I? I involve the entire body I am characterized by muscle rigidity and rhythmic muscle contractions I cause loss of consciousness and incontinence. I can cause a temporary cessation in breathing. Who am I? = Generalized tonic clonic seizures. What does this image say about diagnosing a seizure? Investigate the cause, watch out for seizure and document. What does this image say about diagnosing seizure activity? EEC: Electroencephalogram. What do these images say about etiologies for seizure activity? Look for etiology of seizure…. What provoked the seizure ….. Brain tumor in this case. A brain tumor may present with seizure activity because: a. the tumor compresses the arterial blood supply b. ischemic tissues have high seizure threshold c. brain cells are undergoing apoptosis d. all of the above What do these images say about seizure treatment? …. Restore the balance between neurotransmitters that excite and those that inhibit… decrease excitation and/or increase inhibition. Raise the seizure threshold. Make it harder for the nerve cells in the brain to depolarize. Which of the following are myths? a. people with epilepsy are cognitively challenged b. seizures cause brain damage c. seizure disorder is inherited d. epilepsy is a barrier to success e. all of the above are myths