Seizure / Epilepsy 2020 PDF

Seizure / Epilepsy S. Naghma Rizvi August, 2020 Acknowledgement Muhammad Nisar  Objective Review the basic anatomy and physiology of nerve impulse generation. Define convulsions, epilepsy and seizures List different terms used for epilepsy Identify differe...

Seizure / Epilepsy S. Naghma Rizvi August, 2020 Acknowledgement Muhammad Nisar  Objective Review the basic anatomy and physiology of nerve impulse generation. Define convulsions, epilepsy and seizures List different terms used for epilepsy Identify different causes of seizure Discuss the Pathophysiology of epilepsy / seizures Recognize the classification of seizures  Action potential Cell membrane of excitable tissue contain ions channel responsible for generating action potential. Membrane channel are guarded by voltage dependent gates that open and close with changes in membrane potential Action potential divided into three phases Membrane is impermeable 1. Resting phase or to flow of current carrying ions polarized phase Membrane becomes permeable to sodium ions, rapid flow of sodium ions produce local current ,that travel to adjacent membrane, 2. Depolarization And this causes the sodium channel open in other part of cell. Sodium channel closes, opening of potassium 3. Repolarization channel allows efflux of potassium.  Seizures, Convulsions & Epilepsy Seizures  A seizure represent the abnormal behavior caused by electrical discharge from neurons in the cerebral cortex.  A seizure is a clinical event with associated sign and symptom that vary according to the site of neuronal discharge in the brain.  Manifestation of seizure generally include sensory, motor, autonomic and psychic phenomenon  Seizure is not a disease but a symptom of underlying CNS dysfunction.  Cont… Convulsion  A convulsion refer to a specific type of seizure, a motor seizure, involving the entire body. Epilepsy  The word “epilepsy” is derived from a Greek word meaning “to seize”  Epilepsy is one of the most common disorders of the nervous system, affecting approximately 1% of the world population  Epilepsy is a group of related disorders, not a single disease  Cont.…  A person who has had more than one seizure repeatedly that has occurred spontaneously is said to have epilepsy.  In most cases, the cause of epilepsy is unknown  It can develop at any time of life, the occurrence of new cases is more common in children and in people older than 60 years of age  Few notable people in history have been diagnosed with or are believed to have had some form of epilepsy, those were: Julius Caesar, Albert Einstein, Agatha Christie  Causes of Seizure  Conditions  Diseases  Injuries,  Other factors. Conditions  Atherosclerosis,  Subarachnoid hemorrhage (bleeding into the brain)  brain tumors  Hypoglycemia  Cont…  Chromosomal abnormalities  Congenital diseases  High blood pressure  Pregnancy and associated problems  Stroke  Transient ischemic attack. Diseases  liver disease,  Infections ( brain abscess the brain encephalitis, bacterial meningitis),  Kidney failure (chronic renal failure).  Cont… Injuries  Head injury (motor vehicle accident or sports injury)  Electrical injuries,  Injury during birth or in the uterus  Poisonous insect bites or stings  Additional factors  Alcohol withdrawal  Craniotomy,  High fever especially in young children  Illegal drugs such as cocaine  Lead poisoning  Overheating  Withdrawal from some medicines, including those used to treat seizures.  Pathophysiology 1. May be cause by 2. Decrease inhibition of cortical alteration in brain cell or thalamic Neuronal activity or permeability. structural changes that alter the Or distribution of ions excitability of neurons. across the cell membrane. Calcium influx Potassium efflux Accumulation of calcium 3. Neurotransmitters imbalance such as acetylcholine excess in pre synaptic area stimulate Or GABA deficiency release of neurotransmitters  PATHOPHYSIOLGY GABA is inhibitory Acetylcholine in excitory neurotransmitters neurotransmitter Causes inhibition Causes excitation of cell If Decrease GABA If increase acetylcholine production production Decrease inhibitory Increase excitory effect action Neurons become more Neurons become excited More excited Causes seizures Causes seizures  Clinical Categories of Seizures 1. Unprovoked 2. Provoked Unprovoked is primary or idiopathic with undefined cause. Provoked is secondary or acute and is symptomatic  Symptoms based classification of Seizures  Partial  Generalized  Partial v/s Generalized Seizures Partial Seizure Generalized Seizure Areas of Brain Affects one specific Affect both hemispheres involved area in one of the brain hemisphere of the brain Consciousness May or may not Result in a loss of cause alteration of consciousness consciousness Sign Muscle twitching, Blank stares, falling to Symptoms repetitive motions the floor, sudden muscle jerks, repetitive stiffening and relaxing of muscles  Classes of Partial Seizures  Simple partial  Complex partial  Secondarily generalized partial Aura Aura is a phenomenon that occur prior to seizure, it may include a funny taste, smell, or staring. Some seizures are produce by headache, mood change, lethargy, jerking movement etc,  Simple partial seizures  Affect one specific part of the brain only.  Does not produce an aura.  Do not cause a change in consciousness.  Sudden onset of cortical discharge results in symptoms related to the area of the brain affected  Symptom may include an unusual taste in mouth, vomiting, sweating, or facial twitching. Simple Partial Seizures  Complex partial seizures Affect a larger area of the brain and result in alteration or loss of consciousness  Secondarily generalized partial seizures Begin as a partial seizure in one area of the brain and spread to affect the whole brain  Generalized seizures  Involve both hemisphere  Clinical symptoms include unconsciousness, and motor problems  It includes:  Absence  Atonics  Myoclonic  Tonic Clonic  Absence seizures  Generalized, non-convulsive epileptic event  Expressed mainly as disturbance in consciousness  Occur in children  Characterized by blank ,stare, motionless and unresponsiveness states  Cause brief loss of contact with environment Absence seizures Absence seizures Signs during Seizure: Vacant stare Eyes roll upward Lack of response Previously referred to as a “petit mal” seizure Absence Seizure Atonic seizures (drop attacks)  Loss of muscle tone  Droping of limb  Falling to the ground  Tonic Tonic (few seconds)  Quick loss of consciousness  Limbs either pulled away or towards body, causing fall  Skeletal muscle suddenly tense  Person may express brief loud sound  Clonic Clonic Muscle starts to contract and relaz rapidly Exaggerated twitching of or vibrating limbs Person may roll or stretch Tongue laceration because of jaw contraction Eyes rolled back  Myoclonic seizures  Brief involuntary muscle contraction  Bilateral jerking of muscle  Generalized or confine to face, trunk or one or more extremities  Clonic seizure consists of repeated contraction and relaxation of the major muscle group. Myoclonic seizure  Tonic clonic (grand mal seizures)  Common major motor seizures  Contraction of muscle with extension of extremities  Incontinence  Followed by clonic phase  Relaxation of extremities  Rhythmic movement  Sign and Symptoms  Strange sensation  Perception (hallucination)  Unusual or repetitive muscle movement  Autonomic visceral activity  Confusion state or loss of consciousness.  Status Epilepticus  Complication of seizures  Continuous seizures lasting for at least 30 mins  Remain in comma …. Repetitive seizures  Life threatening condition  Exhausting and dangerous … permanent brain damage Thank you